The role of ascorbic acid on the structural integrity of developing tooth germs.

Tooth germs grown in ascorbate deficient medium for up to 20 days underwent progressive and widespread changes. Proliferation and differentiation of preameloblasts and preodontoblasts progressed normally. Newly differentiated odontoblasts, however, became vacuolated when they began secreting: this suggested a metabolic disturbance. Failure to maintain differentiated odontoblasts, ameloblasts and pulpal cells resulted in aberrant dentin matrix, cessation of dentin production, and finally overall structural collapse with loss of normal morphology. Biochemical studies then were undertaken to define the lesion involved. The relative rate of collagen synthesis in ascorbate deficient cultures was comparable to that of ascorbate supplemented cultures, but the collagen was found to be underhydroxylated. In this state it would be unstable at 37 degrees and subject to preferential degradation. This correlates with the observation that a major fraction of the hydroxyproline in the scorbutic cultures was found in the medium as small molecular weight peptides. The overall effect of ascorbate deficiency was to deprive the tooth germ of the normal quality and quantity of collagen resulting in the characteristic histological and structural abnormalities observed. Flattening and deterioration due to structural failure most likely resulted from abnormal extracellular matrix synthesis in the supportive pulp and dentin due to the aberrant collagen.


[Study of an oral protozoan Trichomonas tenax using scanning and transmission electron microscopy].

The study with scanning and transmission electron microscopy of Trichomonas tenax gave morphological information on this protozoon. The oval-shaped cell body showed at the anterior pole four free flagella and a trailing flagellum which had an undulating membrane. The axostyle which consisted of microtubules and produced the cellular rigidity emerged at the posterior pole. An ovoid nucleus and a well-developed Golgi apparatus were located at the anterior pole. At the latter, a pelta consisting of horizontal microtubulus surrounding the kinetoplats from which started the flagella was also found. No mitochondria were observed: they were replaced by chromatin granules or hydrogenosomes. Numerous vacuoles and developing vesicles were found in the cytoplasm. Phagocytized bacteria were in an advanced stage of lysis. Others seemed intact showing even division phases.


[Changes in the endosteal bone balance in periodontal disease induced in golden hamsters].

The purpose of this study was to analyze through morphometric analysis, the variations of the endosteal bone balance during experimental periodontal disease induced in the golden hamster. The results showed that the osteoclastic resorption is increased by a factor of 5 (p less than 0.01) and the bone formation reduced by about 50% (p less than 0.01). The bone volume decreased slightly (by 6%) but significantly (p less than 0.01). No correlation between respectively resorption and formation and bone volume was found.


SnF2 treatment of enamel, hydroxyapatite or brushite at 37 degrees C and 50 degrees C: an infra-red investigation.

The effect of 4% SnF2 on brushite, hydroxyapatite and powdered bovine enamel applied for short, 15 or 30 minute, periods was investigated using infra-red spectroscopy. It was found that brushite was converted into a fluoridated hydroxyapatite, a reaction which was both time and temperature dependent. The reactions of hydroxyapatite and powdered enamel with SnF2 were similar. There was a drop in the OH- peak intesities. X-ray diffraction analysis of these samples showed that F- ions occupied mainly OH positions in the hydroxyapatite lattice structure. In all reactions an increase in temperature from 37 degrees C to 50 degrees C increased the reaction speed by at least a factor 2. The most probable result of in vivi SnF2 application on sound enamel is the formation of a fluoridated hydroxyapatite together wity stannous complexes and amorphous CaF2. In demineralized areas some of the brushite is converted into a fluoridated hydroxyapatite as is some of the remaining hydroxyapatite. In the more protected area of an enamel lesion these reactions may well continue for some time after the topical fluoride application; Sn2F3PO4 may also therefore be formed.


[Ultrastructure of the connective corium in hereditary gingival hyperplasia].

The ultrastructural study of the gingival lamina propria of 4 patients from the same family with hereditary gingival hyperplasia showed a density increase of the collagen fibres, a decrease in their mean diameter and the dissociation in sub-units of certain fibres whereas their periodicity was not altered. This study showed also the presence of elastic and oxytalan fibres in greater amounts than in normal gingiva, whereas the number of fibroblasts did not seem to increase. However these fibroblasts seemed to undergo modifications in relation to age and to secrete a large quantity of amyloid substance in the extracellular spaces. The glycoproteins and the glycosaminoglycans more abundant than in normal gingiva were not influenced by the age of the tissue.


Perturbation of growth and differentiation of Friend murine erythroleukemia cells by 5-bromodeoxyuridine incorporation in early S phase.

Cultured Friend murine erythroleukemia cells (Friend cells) are induced to undergo erythroid differentiation when grown in the presence of dimethylsulfoxide (DMSO) and other compounds. The effects of unifilar substitution of bromouracil (BU) for thymidine in the DNA (BU-DNA) of Friend cells were examined. Cells were grown in the presence of 5-bromodeoxy-uridine (BrdU) for one generation, then centrifuged and resuspended in medium containing DMSO without BrdU. These cells exhibited a delay in the appearance of heme-producing, benzidine-reative (B+) cells and a decreased rate of cell proliferation in comparison to the control not containing BU-DNA. A transient inhibition of entry into S phase was observed when control cells or cells containing BU-DNA were grown in the presence of DMSO) for 10 to 20 hours. This transient inhibition was increased in the BrdU culture. Thus BU-substitution in Friend cells alters other cellular functions in addition to erythroid differentiation. The rate of increase in the percent of cells committed to differentiate (those forming B+ colonies in plasma clots) was similar in the BrdU and control cultures until 40 to 50 hours. After this time, a delay in the appearance of committed cells was observed in the BrdU culture. The effect of BrdU on the appearance of B+ cells was more pronounced and occurred earlier than its effect on the rate of commitment. Therefore, the delay in the appearance of B+ cells in the BrdU culture was due primarily to perturbation of post-commitment events such as the accumulation of hemoglobin. We also examined the effect on growth and differentiation after BrdU was incorporated during different intervals of S phase in cells synchronized by centrifugal elutriation or by double thymidine block and hydroxyurea treatment. The delay in the appearance of B+ cells and inhibition of cell proliferation were only observed when BrdU was incorporated in the first half of S phase. BrdU (10 muM) had no effect on growth or differentiation when present during late S or G1 and G2. These results, using two very different methods to achieve cell synchrony, indicate that the effects of BrdU on growth and differentiation described above are due to its incorporation into DNA sequences replicating during early S.


Alterations in chloride transport during differentiation of Friend virus-transformed cells.

Friend erythroleukemic cells can be induced by a variety of agents to synthesize hemoglobin and to exhibit other characteristics suggesting erythroid maturation. Upon induction of hemoglobin synthesis with dimethylsulfoxide (DMSO), the chloride flux in Friend cells gradually increases, until after five days of exposure to DMSO (when the hemoglobin content of the cells approaches that of the mature erythrocyte) the flux is three times the value in non-induced cells. A similar flux increase is observed in the presence of a different type of inducer, hypoxanthine, but no increase in flux is seen in the mutant cell line, TG-13, which does not synthesize hemoglobin after DMSO treatment. Thus, the flux increase seems to be associate d with the induction process, rather than being a direct effect of the inducing agent. After DMSO treatment, the sulphate flux decreases and the chloride/sulphate selectivity increases, aswould be expected if the cells were becoming more like red cells. On the other hand, the sensitivity of the chloride flux to the inhibitor, furosemide, and to temperature is the same in the induced as in the non-induced Friend cells, and different from that of the mature red cell. Thus, the anion transport properties of the induced Friend cell are different from those of both the non-induced Friend cell and the mature erythrocyte. Either the system in the induced cell represents an intermediate stage in the development of the mature red cell characteristics, or else the maturation of transport function in the Friend cell differs from that in normal erythrocyte precursors.


Early decrease of 2-deoxy glucose and alpha-amino isobutyric acid transport are among the first events in differentiating synchronized murine erythroleukemia cells.

Murine erythroleukemic cells were induced to differentiate along the erythroid pathway by Me2SO and HMBA. These inducers caused an early decrease in the transport of glucose and amino acids, both in non-synchronized and in synchronized cultures. Careful analysis of the transport parameters in synchronized cultures showed a cyclic fluctuation of the Vmax but no significant change of the Km. in the presence of the inducers, however, a modification of the Km and Vmax of both carriers was observed which was not dependent on cell cycle. This modification is very early and procedes the transient arrest of the cells in G1 reported previously. In addition, a Me2SO-resistant cell line (DR10) does not show any changes in the transport of glucose and amino acids when incubated with Me2SO. However, there is an effect on the transport when incubated with HMBA which induces differentiation of 50% of the cells. These data support the hypothesis that an early effect of the inducers on the plasma membrane may be a necessary prerequisite for initiation of differentiation in murine erythroleukemic cells.


The angular bone defect and its relationship to trauma from occlusion and downgrowth of subgingival plaque.

Sixty-four sets of human teeth were collected with the aim of evaluating the role of trauma from occlusion in the etiology of destructive periodontal disease. Before the jaws were taken out, a careful bite analysis was carried out. After fixation of the jaws, impressions were taken and plaster of Paris models were made. Finally, a set of 14 radiographs were taken. On the basis of the "clinical" records postmortem, the study models and the radiographs, the jaws were sectioned. Only mesio-distal sections were included in the present analysis. The total number of interdental spaces examined was 106. The following observations were made: 1. Before any loss of periodontal fiber attachment has taken place, the configuration of the interdental septum is entirely dependent on the location of the cemento-enamel junction (CEJ) of the two neighboring teeth. The alveolar crest does not approach the apical border of the junctional epithelium closer than about 1 mm. Thus, if the CEJ is located at different levels on two neighboring teeth, the marginal termination of the interdental septum will be oblique, forming an acute angle with the "lowest" tooth. 2. Loss of periodontal fiber attachment could invariably be related to the apical growth of subgingival plaque, and downgrowth of plaque was always associated with an inflammatory process which involved lysis of the attachment fibers within a distance varying between 0.2 and 1.8 mm from the apical border of the plaque. Subsequently, the JE proliferated down to cover the denuded root surface. 3. Reduction in height of the alveolar crest could also be related to the downgrowth of plaque. The distance from plaque to bone was never found to be less than 0.5 mm and never more than 2.7 mm. The configuration of the interdental septum always seemed to be determined by the level of the plaque on the two neighboring tooth surfaces. Thus, if the plaque had reached the same level on both sides, the crest of the interdental septum assumed a horizontal outline; if plaque had proliferated down to different levels, the crest of the interdental septum was oblique and an angular defect hereby established. 4. In the present material no evidence was found to indicate that functional (traumatic) forces can act as a co-factor in the causation of angular defects. In fact, such defects were found equally often adjacent to "nontraumatized" as to "traumatized" teeth. 5. Infrabony pockets were invariably associated with downgrowth of subgingival plaque.


Assessing the periodontal treatment needs of a population.

A longitudinal study was conducted on 106 patients attending a dental school and undergoing periodontal treatment, to assess the relationship between some commonly used periodontal indices and the time taken to treat periodontal disease. The data were analysed by assessing the times taken for examination motivation, scaling and surgery for persons with ranges of indices such as D.I., C.I., O.H.I., G.P.I. (Ging), G.P.I. (Perio), G.P.I. (Comp) and P.I. A one-way analysis of variance was carried out to test the significance of trends. Next, a Spearman correlation coefficient was calculated for each index and its components and treatment time. The index which correlated most closely with examination time was the P.I. The G.P.I. (Ging) was the best predictor of motivation time and three indices, C.I., G.P.I. (Perio) and P.I. correlated significantly with scaling times. The P.I. and G.P.I. (Perio) correlated with surgery time. By converting periodontal indices into treatment times, planners can estimate with a fair degree of accuracy the time and resources required to carry out periodontal treatment for a population.


Oral hygiene levels and behaviour in pre-clinical and final-year dental students.

The oral hygiene levels and behavior in pre-clinical and final-year dental students attending Birmingham University 1977 were investigated. Gingival inflammation, bacterial plaque and calculus accumulations were clinically recorded. Tooth cleaning habits were assessed by a questionnaire. Oral hygiene habits differed between the two groups and an improvement in oral hygiene levels was evident in the final-year students. Statistically significant differences (P is less than 0.05) were found between the plaque index scored of the pre-clinical and final-year students, and for the gingival and calculus index scores of the male students. Thus in this investigation it was possible to show that improvement in oral hygiene does occur between the pre-clinical and final year of the undergraduate course.


The role and responsibilities of a department of medicine in a school of dentistry.

In each school of dentistry there is a place for a department of medicine that can help prepare the dentist to provide dental care for the increasing number of patients with organic disease. The department of medicine can provide consultative services to the medical profession in the dentist's area of specialization.


Reliability of the medical history in identifying patients likely to place dentists at an increased hepatitis risk.

Blood was sampled for all new patients entering a dental school clinic to determine the presumed carrier prevalence in such a population. In a second portion of the study, serologic testing was completed for 140 patients who had a history of hepatitis infection or exposure to hepatitis, or who otherwise were part of a group likely to have a high incidence of hepatitis. The results from the test were compared with the information given by the patients.


Self-regulation in the dental profession.

Structured and open-ended questions were posed in a survey of dentists in solo and nonsolo practices to test assumptions concerning clinical norms and the self-regulatory aspect of the health professions. The importance of autonomy in their perceptions of practice influenced the dentists' responses to several developments; among them are peer review and third party programs that affect the profession.


Illumination of the dental operatory.

With the use of the two types of fixtures described in this paper and some precautions taken to reduce glare, the quality of lighting in the dental operatory can be improved.


Transpositional flap technique for mandibular vestibuloplasty.

Various surgical techniques for a mandibular vestibuloplasty have been advocated. A transpositional labial flap technique used by us for 23 patients since May 1976, and based on a procedure described by Edlan, has been presented with results of nine-month follow-up examinations of six patients. Clinical, radiographic, and histological evaluations completed at three-month intervals showed that this transpositional vestibuloplasty compared favorably with other similar techniques in postoperative time of healing, condition of attached mucosa, stability of increased vestibular depth, and amount of resorption of labial bone. Advantages of this procedure over other mandibular vestibuloplasty techniques are its simplicity, low morbidity, decreased operating time, feasibility of use of local anesthesia and conscious sedation on an outpatient basis, and elimination of the need for a graft. The disadvantage of the procedure is that it requires healthy preexisting vestibular mucosa for optimal results.


Repair of gingival clefts.

Two cases of extensive gingival clefts are presented with surgical methods used for their correction. The theoretical basis for their pathogenesis is briefly described.


Immediate permanent reconstruction of a mandibular continuity defect with use of a prosthesis of chromium-cobalt alloy.

A report of ten-year follow-up examinations of a patient who had a hemimandibulectomy with disarticulation because of fibrous dysplasia and immediate permanent reconstruction of the mandible with a Vitallium custom-cast prosthesis is presented. Careful preoperative planning, operative technique, and postoperative follow-up examinations are essential for successful maintenance of the prosthesis. Autogenic bone grafts are, in general, superior to alloplasts in permanent reconstruction of defects in mandibular continuity after resection. However, there are indications for alloplastic reconstruction when the condyle is disarticulated with the resection.


The necessity of updating dental examining boards.

Though state boards may be necessary, let them be less anachronistic in the expectations they have for current graduates. Let us hope that the state and regional boards will change and keep pace with the current literature. The boards can have an influence on upgrading dentistry but only if they are progressive, and if they do not hold back the profession by demanding antiquated means of looking at dental care for the patients.


Model curriculum for forensic dentistry in US dental schools.

A model curriculum for forensic dentistry in US dental schools has been presented. This curriculum follows guidelines that will provide the dental student with practical training in specific forensic techniques, knowledge of general principles of forensic dentistry, and an appreciation for the dentist's responsibility within the legal community.


Short-needle block anesthesia at the mandibular foramen.

Thirty-five cadavers were studied to determine the depth of penetration of the needle from the oral mucous membrane to the inferior alveolar nerve at the mandibular foramen. The depth of penetration at the narrowest anteroposterior width of the ramus and pterygotemporal depression was determined to be half the narrowest anteroposterior width of the ramus plus or minus 1 mm. This depth was within the limits of a short needle. It was easier to estimate the depth of penetration with a short needle than with a long needle. A short needle also was less likely to go too deep and deviate from its course than was a long needle.


Concentrations of cephalexin in mandibular alveolar bone, blood, and oral fluids.

Results from this study of 16 patients who underwent extractions and alveoloplasty indicate that cephalexin effectively penetrates alveolar bone. After cephalexin had been administered, 500 mg four times a day for 48 hours, the average concentration in bone exceeded the average minimal inhibitory concentration of six organisms commonly encountered in infections and bacteremias of dental origin. These data and the current knowledge of cephalexin suggest that cephalosporins may have a unique use in dental infections or potentially harmful bacteremias caused by susceptible organisms.


Forensic identification of burn victims.

An explosion and fire that caused $25 million in damage caused the deaths of seven men, four of whom could not be identified through ordinary methods. Three of these four victims were positively identified through forensic dentistry techniques. Dental records, particularly radiographs, of all patients should be retained should the dentist be called on to aid in the task of identification.


Accidental hydrofluoric acid burns of the hand.

A case report of accidental hydrofluoric acid burns that involve dermal tissue of the hand is presented. Prompt medical treatment for this accident resulted in minimal disfigurement and minimal paresthesia and disability. Protocols for essential treatment and precautions for personnel working in dental laboratories where hydrofluoric acid is used have been discussed.


Physical evaluation system to determine medical risk and indicated dental therapy modifications.

The physical evaluation system allows the practitioner to rapidly classify each patient according to medical risk and thus to provide dental treatment comfortably and safely. The evaluation system serves as a guide to the level of dental therapy, deisions of management, and modification of treatment for the medically compromised patient. Extensive use of the ADA physical status classification system in dentistry would allow meaningful studies of morbidity and mortality that are related to various management protocols and could conceivably have an impact on insurance schedules associated with psychosedation modalities and general anethesia on an out patient basis. A physical evaluation system cannot substitute for knowledge and good judgment. Recommended categories of physical status and modification of treatment should not be considered as absolutes, but as guides. Wheras the guidelines may appear to be inflexible, they should not be considered as such. Deviation from recommendations is often justified and is expected.


Root canal morphology of the maxillary first premolar.

Four hundred maxillary first premolars were decalcified, injected with dye, cleared, and studied. The canal configurations were categorized as: 26% had one canal, 69% had two canals, and 5% had three canals at the apex. The relationship of canal configuration to number of roots per tooth was determined. Of the canals studied, 49.5% had lateral canals. They occured equally in all types of canals, were located mainly in the apical region, and exited from the main canal mostly in a palatal direction. Also, 11% of these canals extended from the floor of the pulp chamber to the furcation area. An accurate knowledge of the morphology of the pulp cavity is essential before endodontic procedure can be approached rationally. The frequency with which root canals unite should be considered during enlargement and filing procedures. The dentist also should be aware of the possible existence of bifurcated and double canals if root canal therapy should unexplainbly fail. A knowledge of these variations will assist the dentist in reaching conclusions when diagnosing and treating endodontic cases.


Enamel pearls as contributing factor in periodontal breakdown.

Removal and treatment of an enamel pearl, a contributing factor to periodontal disease because of its anatomy and location, are described.


The arrangement of muscle fibres in cleft lips.

A total of 63 laterally situated partial clefts of the lip were studied. The biopsies obtained during the first operation were evaluated histologically. With a special stain, the fibre of the orbicularis oris muscle were demonstrated and their arrangement in relation to the cleft lip was recorded. The results indicate a close relationship between type and degree of the cleft and the arrangement of the muscle bundles: In microforms like lip indentations and minor clefts of the lip the natural anatomy is almost unaltered. The muscle "flows" around the "obstacle". But the larger the cleft the more often the muscle fibres end right at the border of the cleft and insertions are often found here. In the remaining skin bridge the number of muscle fibres decreases and their arrangement deteriorates. In the extreme forms, i.e. the band of Simonart and the completely cleft lip, we must assume that most of the fibres stop at the border of the cleft as muscle no longer crosses the defect.


Velopharyngeal anatomy and maxillary advancement.

This study was undertaken to evaluate the radiographic changes in the static velopharyngeal mechanism following total maxillary advancement. Records of 21 patients treated for maxillary retrusion were evaluated. Two groups were present: 13 non-cleft patients and 8 cleft-lip patients. The findings demonstrate an anatomical change in the velopharyngeal mechanism following total maxillary advancement. A similar change occurred in both groups; however, the magnitude is differed. The angle of the soft palate to hard palate increased with surgery (2 degrees per mm. advancement noncleft and 1 degree per mm. cleft). An increase in soft palate length was also seen (.5mm. per mm. advancement non-cleft and .4 mm. per mm. cleft). A pharyngeal need ratio prediction method was established (pharyngeal depth/soft palate length). A ratio of .68--.84 in this study was observed. A ratio greater than one was found to indicate probable velopharyngeal incompetence.


Incidence and clinical differentiation of odontogenic tumours.

The odontogenic tumours represent a group of interesting and fascinating changes in tissue which demonstrate a confusing picture of uncontrolled odontogenesis. A lack of knowledge of actiology, extraordinary rarity, polymorphism in their nature and lack of agreement on a commonly accepted nomenclature and classification put nearly insurmountable difficulties in the way of every experiment to gather and analyse the clinical behaviour of the different forms of these tumours. Initially, differential diagnostic criteria defining each form of tumour were derived from representative combined statistics in the world literature; simply registered findings as to age, sex, site and "characteristic" X-ray appearances were evaluated and registered tubularly. The "Histological Tying of Odontogenic Tumours, Jaw Cysts, and Allied Lesions", published by WHO in 1971, was chosen and taken as the basis for our evaluation, together with the sparse data in the literature concerning the absolute and relative frequency of these tumours.


Osteoma of the ethmoid and lacrimal bone.

The true osteoma is a benign tumour, which mainly occurs in the bones and cavities of the middle third of the face. This article discribes a case of a true osteoma of considerable size arising from the junction of the lacrimal and ethmoid bones of a 19-years-old boy causing limitation of the field of vision.


Zygomatico-coronoid ankylosis secondary to heterotopic bone formation: combined treatment by surgery and radiation therapy--a case report.

Zygomatico-coronoid ankylosis is a rare, extra-articular form of ankylosis of the jaws. An unusual case is presented in which true bony zygomatico-coronoid ankylosis was produced by a mass of heterotopic bone. Surgical treatment consisted of an oblique ostectomy across the mandibular ascending ramus, with interposition of Silastic sheeting to form a pseudarthrosis. Since surgery is often the stimulus for this condition, 2000 rads were delivered to the surgical site postoperatively in order to inhibit recurrent heterotopic bone formation. The rationale and indications for this form of treatment are discussed.


Syndromology's message for craniofacial biology.

Syndromology is a misunderstood specialty that has much to contribute to the understanding of cranio-facial biology in general and the study of craniofacial anomalies in particular. An introduction to the practice of syndromology and the rudiments of syndrome delineation is presented. The aetiology and pathogenesis of selected craniofacial anomalies (Robin complex, hemifacial microsomia, and craniosynostosis) are considered from the perspective of syndromology.


Effect of antibiotics on platelet thromboplastic function and thrombin activity.

Carbenicillin (CB-PC), sulphobenzylpenicillin (SB-PC), ampicillin (AB-PC), benzylpenicillin (PCG), cefazolin (CEZ), cephalothin (CET) and cephaloridine (CER) were used in vitro for the experiments. Recalcification time was prolonged by AB-PC, SB-PC, CB-PC and CER at the 10(-2) and 10(-3) M level. Prothrombin time (PT) was prolonged by AB-PC, CEZ, CET and CER at the 10(-2) M level. Plasma antithrombin activity was not affected by any antibiotics tested at the 10(-2) and 10(-3) M level. The platelet thromboplastic function of the human platelet suspension and free platelet factor III were reduced more than 40% by all antibiotics used except for PCG at the 10(-3) M level compared with controls, showing no significant difference in the degree of reduction between these two samples. When antibiotics were preincubated with albumin solution, the reduction of platelet thromboplastic function was greatly inhibited except with CB-PC and CER. Factors of bleeding caused by intramuscular injections of the antibiotics are discussed.


Carcinoma of unknown primary: natural history and response to therapy.

Twenty-three consecutive patients with metastatic carcinoma of unknown primary referred to a medical oncology service over the past two years were studied. In the majority of patients, death occurred within one year of diagnosis and a priamry site of disease was identified at postmortem examination. Of patients who had a primary site identified, findings suggestive of involvement of that site were present during the course of their illness. Survival was greatest in patients with adenocarcinoma histology, with lymph node site of presentation and in those treated with both radiation therapy and chemotherapy, although these differences were not statistically significant. Despite the prolonged survival of a few patients, it is clear that failure to extensively evaluate subtle clinical findings and the lack of efficacious therapy for the malignancies commonly encountered seriously limit the survival of the vast majority of these patients. The identification of new tumor markers and the use of adjunctive chemo-immunotherapy to excisional surgery may ultimately improve to outlook for these patients.


Blood effects of permanent normoxic hypercapnia in conventional rats.

Rats were exposed 24 hours a day to carbon dioxide, 8 +/- 1%, during 2 and 4 weeks under normoxic conditions (21% oxygen). On the last day, blood was taken from the abdominal aorta under anesthesia. Leukocyte and erythrocyte counts, hemoglobin concentration, and mean cell volume were electronically measured. Hematocit and Wintrobe indexes were calculated. Leukocyte differential counts and peroxidase activity were determined on blood smears. After 4 weeks of hypercapnia, a slight decrease of neutrophilic granulocytes was observed. In mature polymorphs, peroxidase activity (cytochemically demonstrated) simultaneously decreased. Erythrocyte counts and mean cell volume remained unchanged. The most important hematological disturbance was an hemoglobin concentration drop. Consequently, it was concluded that an hypochromic anemia characterized the permanent normoxic hypercapnia in rats.


Comparative effects of canbra oil and butter on lipdemia, vitamin A tolerance and thrombosis factors in man.

In a five-day clinical test, the dietary effects of canbra oil and butter on normal human subjects were studied with special reference to lipid metabolism, clotting times and platelet functions. There was no difference between the canbra oil and butter diets as regard triglyceridemia or clotting times, but cholesterolemia and in vitro platelet aggregation by ADP dropped significantly in subjects fed the canbra oil diet. The platelet count did not change significantly. A possible explanation of these results might to be the difference in the fatty acid composition of canbra oil and butter.


The failure of long term effect of cyclophosphamide on systemic immunologic connective tissue disease in rabbit.

Cyclophosphamide is given intravenously in the high dose of 12 mg/kg/day during 2 months from the beginning of immunological systemic connective tissue disease in rabbits, according to the modified Glynn's model. The effects of this alkylating drug are studied after the termination of treatment. At short term (15 days), cyclophosphamide depresses the inflammation of synovia in stimulated and non-stimulated joints, the humoral and cellular immunities, but the drug does not modify the other systemic lesions. At long term (between 1 and 6 months), these effects of cyclophosphamide disappear completely.


Lymphocyte functions in Wegener's granulomatosis.

Lymphocyte function was examined in Wegener's granulomatosis patients and the following results were obtained. 1) The T and B lymphocyte subpopulation was within the normal range. 2) Lymphocyte blast formation was examined with the use of PHA-P, Con A or TAP (tuberculin active peptide). A decrease in responsiveness against TAP was found in four out of ten patients, but no decrease was observed in responsiveness agains Con A or PHA-P. 3) Skin tests were carried out on seven patients with six different antigens. In two out of seven patients, the skin reactions were decreased against all the antigens used. In the other five patients, skin reactions were observed against only one or two of the antigens used. These results suggest that Wegener's granulomatosis may be associated with a partial deficiency in the cellular immune mechanism.


Influence of muscle pain tolerance on muscle pain threshold in experimental tooth clenching in man.

Ten adults and ten children exercised maximal voluntary tooth clenching until pains appeared in the jaw muscles, i.e. the muscle pain threshold of tooth clenching was determined. Subsequently, the subjects were instructed to exercise tooth clenching until they were forced to stop because of intolerable pains and exhaustion of the contracting muscles, i.e. the muscle pain tolerance of tooth clenching was recorded, and during these bouts of clenching the pain tolerance of tooth clenching was recorded, and during these bouts of clenching the pain threshold was also determined. In adults, determination of the pain tolerance decreased the pain threshold by 19%, and in children it either decreased the pain threshold by 20% or increased it by 56%. It is proposed to introduce the muscle pain tolerance of tooth clenching as an adjunct in the clinical examination of cases of facial pains presumed to originate from the jaw muscles, but the test should be interpreted with caution.


Change in the gonial angle.

Cross-sectional studies have promoted the view that the gonial angle is increased by age and by the edentulous state. Longitudinal studies do not support this view. It is proposed that the data support the concept that the gonial angle may show enlargement or reduction, as may be expected of any bony angular relationship, and that ageing and loss of teeth are not, and should not be expected to be, the sole determinants of such change.


Crevicular temperature rises stimulated by plaque formation.

In nineteen subjects, temperatures were recorded thermo-electrically in the vestibular and proximal crevices of fifty-nine teeth. It was found that the formation of a new plaque was followed by a rise in crevicular temperature. In addition, it was found that the normal as well as the abnormal crevicular temperatures were higher in the mandible than in the maxillae.


Investigation of the strain produced in maxillary complete dentures in function.

An experiment has been completed to investigate the strain levels obtained on polymethylmethacrylate dentures in function when biting and swallowing. The use of stacked, rosette strain gauges enabled the magnitude of strain in the material underlying the gauge to be calculated and, in addition, the direction of the principle maximum and minimum strain was also calculated. Strain in the denture base was measured in biting and swallowing with a normal occlusion, when the occlusal contact area was narrowed, and with the rosette gauges.


Mucosal temperature rises following long-term use of full dentures.

Mucosal temperatures were studied in twenty-two subjects, who had worn full upper and lower dentures for at least 5 years. By comparing with a group of twenty-two fully dentate subjects, it was found that in the denture wearers, temperatures were increased significantly in the lower jaw, but not in the upper jaw.


Oral recognition of forms and oral muscular coordination ability. A longitudinal study in young adults.

A study has been carried out to investigate the constancy of results in oral recognition of forms (RF-test) and in tests which demand a fine coordination of the oral muscular apparatus (MA-test). Twenty examinees with a mean age of 22.5 years were tested with both test forms in 1972 and retested 4 years later in 1976. The performances in the RF- as well as in the MA-test improved considerably. As to the learning (training) effect in both test forms, the test results acquired by training during the previous period have largely been preserved until the next test period 4 years later. Individuals with a given capacity to perform either the RF- or MA-test, showed about the same grade of ability 4 years later. The RF- as well as the MA-test seem to reflect a given ability, which, at least in this age-group, remained constant during a period of 4 years. These results may be explained by reference to the notion of schema in which some motor-sensory feed-back will be stored. The specificity of the perceptual and motor patterns used, may have produced schemata with good resistance against forgetting.


Bone loss of edentulous alveolar ridges.

RRR is probably multifactorial process subject to a wide number of covariables. In any given patient, these convariables will be in a unique combination which will determine the rate of RRR for that patient at that time. If the variable change in any given patient, the rate of RRR may change. The dentist who wishes to help his edentulous patient should seek to be sensitive to all these variables, and to understand and treat that unique combination of factors which exists in that patient.


Unilateral optic neuropathy following vincristine chemotherapy.

Two subjects with acute lymphatic leukemia have been observed to have unilateral optic neuropathy five to seven days following administration of Vincristine (2.0 mg/sq m) during maintenance chemotherapy. Both subjects were in mission at the time their ocular problems developed. After discontinuance of Vincristine therapy, marked vision improvement in the affected eye occurred over the ensuing months. It is presumed that Vincristine therapy was the cause of toxic optic neuropathy in these patients.


Untreated periodontal disease: a longitudinal study.

Thirty diagnosed but untreated patients with moderate to advanced periodontal disease were examined a minimum of two times. The examination time intervals ranged between 18 and 115 months. 2. A total of 83 teeth were lost between examinations. 3. Excluding a patient who lost 25 teeth, a total of 58 teeth were lost. The adjusted tooth loss was 0.61 tooth per patient per year (or 0.36 with the elimination of 22 "hopeless" teeth). 4. The mandibular and maxillary molars had the greatest percentage of tooth loss between examinations. 5. All 29 patients completing the study had progessive increases in pocket depth during their time in the study. Increases in the mean annual pocket depths per tooth per patient varied from 0.24 millimeter per year to 2.46 millimeters per year. 6. The disto-lingual and mesio-lingual interproximal surfaces had the greatest increases in surface pocket depths. The lingual and buccal surfaces had the smallest increases in pocket depth. 7. The rate of increase in pocket depths was less in patients over 44 years of age. 8. The teeth which were lost had greater initial pocket depths and mobility scores than those which were present at both examinations. 9. There was no correlation between increases in pocket depth and changes in mobility. 10. All 29 patients showed radiographic evidence of progressive bone resorption between examinations. The posterior segments of the mouth had the largest amounts of bone loss between the first and last examinations.


Healing of the oral mucosa with the use of collagen artificial skin.

Wounds were prepared in the oral cavity of 15 rabbits and five dogs, and an enzyme-solubilized calfskin collagen was placed over the surgery sites on one side. The contralateral sides acted as controls. Results indicated that the membrane was biologically acceptable to the oral mucosa of rabbits and dogs. Th collagen did not cause any adverse reaction and may have been responsible for the clinical impression of slightly more rapid healing of the gingivae in dogs. Clinical implications of this material's utilization produce some exciting ideas for future research.


A laser instrument for measuring tooth movements.

An improved apparatus has been constructed which is based upon the laser reflexion method and is used in a highly accurate direct technique of measuring tooth movement without contact. The possibility of making clinical investigations of tooth movements with the equipment has been investigated by testing its various components. The most critical part of the system is the repositioning of the patient, which has been done with an accuracy of +/- 20 micron. The reflected pattern used during 3 months of experiments was the same. The instrument can be used for measurements down to 50 micron.


Concentration of circulating hormones and metabolism of androgens by human gingiva.

The present study evaluates the relationship between periodontal status, concentration of circulating hormones and metabolism of androgens by human male and female gingiva in vitro. In both male and female patients with healthy gingiva the plasma concentration of gonadotropins (LH and FSH) and steroid hormones (testosterone, androstenedione, estradiol-17 beta, progesterone and cortisol) were in a normal range. However, an alteration in the plasma concentration of progesterone was found in both male and female patients with periodontal pathosis. Both androgens (testosterone and androstenedione) were readily metabolized by human gingiva tissue in vitro. The major pathway of the metabolism of testosterone was via the formation of 17 beta-hydroxy-5 alpha-A-ring reduced androgens (5 alpha-dihydrotestosterone and 3 alpha-, 3 beta-androstanediol). In contrast, androstenedione was metabolized mainly to 17-keto-5 alpha-A-ring reduced (5 alpha-androstanedione, androsterone and epiandrosterone) and 17 beta-oxidoreduced (testosterone) compounds. In addition both substrates were metabolized to 5 beta-A-ring reduced androgens (5 beta-dihydrotestosterone, 5 beta-androstanediol and 5 beta-androstanedione). A significant feature of the metabolism of testosterone and androstenedione by inflamed gingiva was an increase of 5 alpha-A-ring reductase activity (mainly the formation of 5 alpha-dihydrotestosterone and 5 alpha-androstanedione) and 17 beta-oxidoreductase activity (mainly the formation of testosterone from androstenedione). The increase in 5 alpha-reductase activity also showed a significant correlation with the plasma progesterone concentration.


Plasma female sex-hormone levels and gingivitis in pregnancy.

This investigation has confirmed that there is an increase in gingival inflammation between the 14th and 30th weeks of pregnancy and that this will occur despite a fall in the amount of plaque at the dento-gingival junction. This implicates a further factor in addition to plaque accumulation to explain the increased inflammmation. It was confirmed that there are marked increases in the plasma levels of estradiol and progesterone between the 14th and 30th weeks of pregnancy but it was not possible to demonstrate a direct association between these increases and the increase in gingival inflammation.


An evaluation of the root topography following periodontal instrumentation--a scanning electron microscopic study.

Extraction was performed on 52 periodontally involved teeth. Of these, ten without any instrumentation served as controls, 19 were treated with hand instruments, and 23 with ultrasonics. The extent of cleaning and damage to teeth with the two treatment procedures employed were assessed by examining in the scanning electron microscope. Ultrasonics were superior in the treatment of incisor teeth but had no particular advantage over the hand instruments with respect to the treatment of molars. Also the microflora forming the bacterial plaque were visualized.


The lingual pedicle. Case reports.

Poorly constructed and inadequately fitting mandibular removable partial dentures may be etiologic factors in producing localized lingual gingival recession. Two cases presented show that despite the limitations of access and muscle pull in the lingual mandibular anterior region, both full and partial thickness lingually laterally rotated pedical flaps can be successful in repairing denuded roots by root coverage and by increasing the width of keratinized attached gingiva.


Edentulous area tissue graft correction of an esthetic defect. A case report.

A patient was left with a severe defect following the extraction of the right maxillary lateral and central incisors. A graft of epithelial and connective tissue was taken from the maxillary tuberosity and placed into the defect. This resulted in the filling of the defect and the correction of the esthetic problem.


Fabrication of a maxillary occlusal treatment splint.

A technique has been described which results in a high-quality occlusal splint by duplicating the centric relation record in acrylic resin. Each fabrication step has been thoroughly controlled. The major advantage of the technique is a reduction in clinical appointment time.


Flasking technique for large facial prostheses.

By utilizing the giant press and the plastic pipe flask, large facial prostheses can be flasked and processed to allow thin, well-adapted margins without distortion. The plastic flask is easily stored for a remake of the prosthesis at a future date if it should be necessary.


Heat-released stress in acrylic dentures.

Dimensional changes in an acrylic resin denture blank that are sufficient to cause changes in fit on a gypsum cast occur primarily when the dentures are heated in water to a temperature of 90 degrees C or more. The poor correlation between observed fit and the intermolar distance change indicates that the dimensional change of dentures is much more complex than suggested previously and may be the product of factors that are not as yet fully understood. Enough heat to cause distortion of the denture can be produced during the process of grinding the denture. It should be recognized by the dentist, the dental assistant, and the dental laboratory technician that denture resins are sensitive to the techniques that are used in finishing. Overheating even small regions may allow localized dimensional changes that result in distortion of the denture.


Color stability of temporary restorative materials.

In this study it was shown that: 1. There was a statistically significant initial color difference in materials labeled shade 65. 2. Rough materials darkened significantly more than polished materials. 3. There was not statistically significant over all difference in the amount of staining between air-cured and pressure-cured samples. 4. The methyl methacrylates materials demonstrated that least darkening, followed closely by the ethyl-methyl methacrylate material. The vinyl-ethyl methacrylate material darkened consistently more in 14 and 30 days and significantly more at 60 days. The epimine material was consistently the least color stable and showed a significantly greater amount of darkening.


Crown-to-root ratio: its significance in restorative dentistry.

The definition of the crown-to-root ratio, its manifestation as a clinical problem, and associated problems were reviewed. Treatment possibilities were discussed in terms of plaque control, periodontal surgery, occlusal adjustment by selective grinding, splinting, restorative considerations, and extraction. The original guidelines for crown-to-root ratio in the selection of abutments were found to be exceptionally conservative and treatment limiting. New treatment modalities were considered in light of increased understanding of periodontal inflammation and its control. With inflammation controlled and with a carefully designed occlusion, some degree of mobility may be tolerated, thereby permitting the retention of teeth with minimal alveolar support.


Evaluation of clinical methods for assessing the surface roughness of restorations.

Using four different clinical methods to assess the surface roughness of Concise and Spheraloy samples finished with four different treatments, two dentists untrained as evaluators found the following: 1. Although the control profile measurements showed significant differences both between the two materials and the four surface treatments (p less than .001), no clinical assessment method differentiated clearly between all treatments, especially for Concise. 2. Differentiation between the surface treatments was shown best for Spheraloy by the clinical criteria, abraded glass blocks, and ranked photographic negatives. For Concise the best results were shown by the clinical criteria and abraded glass blocks. However, evaluator agreements were highest for Spheraloy with the ranked replica profiles and photographic negatives. For Concise the highest agreements were with the ranked replica profiles. 3. Differentiation between pairs of each material finished with the same surface treatment was shown best by the ranked replica profiles and photographic negatives. These two methods also gave the highest evaluator agreements. 4. Where possible, the use of suitable visual ranking assessment methods rather than clinical ratings or scores to assess surface roughness is preferred for dentists untrained as evaluators.


Vapor-deposited carbon-coated tooth root implants: preliminary evaluation of a stylized tooth implant system in dogs.

The results of this preliminary evaluation of a tooth implant model combining a stylized tooth root design and a thin, highly biocompatible microporous carbon coating, although tentative, add support to the feasibility of developing a statisfactory system for the immediate replacement of selected teeth in healthy bone.


Spectrophotometric study of five porcelain shades relative to the dimensions of color, porcelain thickness, and repeated firings.

A total of 125 ceramo-metal samples were used representing: 1. Five different porcelain shades a. Ceramco shades A3, B2, and D3. b. Vita B2. c. Biobond B62. 2. Thicknesses of 1, 2, and 3 mm for each shade fired two times 3. Additional 2 mm samples for each shade fired five and 10 times. Each sample was analyzed by a recording spectrophotometer. Data received was converted to Munsell notation for evaluation of the dimensions of color, i.e., Hue, Chroma, and Value, as related to (1) shade differences, (2) thickness of porcelain, and (3) numbers of firings.


Hinge axis location on the articulator.

Experiments were undertaken to determine the accuracy of hinge axis location using clinical methods on articulator. Errors were found to occur up to an area 2.4 mm in diameter, but most of results were more accurate than this. Results were better with an opening in the anterior region of the articulator of 15 mm rather than 10 mm. It would appear that better results could be obtained using a microdot pattern flag rather than a plain record blank to determine the rotation center. The first experiment gave good results, although only one participant had any previous experience of hinge axis location, and it is debatable whether or not this experience is necessary before satisfactory results can be obtained. The only statement which can really be made from these results concerning the value of previous experience is that with a plain flag, previous experience is more helpful for an articulator opening of 10 mm but not for an opening of 15 mm. The results of these experiments are in keeping with those of other investigators.


Comparison of some properties of polyether and polysulfide materials.

Based on the present measurements on working time, setting time, and compression set of polyether and polysulfide materials, the following observations were made: 1. The manufacturer recommends a working time for polyether that is approximately 40 seconds more than that indicated by the clinical or ADA test. 2. Clinically, if more working time is desired, polysulfide impression material should be used. 3. Polysulfide material is more sensitive to temperature change than the polyether material. 4. If the material is allowed to set longer, the percentage change in compression set decreases. 5. For polyether, an increase in setting time of 2 minutes will significantly reduce the distortion of the impression upon removal.


Surgery for internal derangements of the temporomandibular joint.

Three hundred and twenty-seven reconstructive arthroplasties and disk repositionings have been performed during the past 6 years at Montgomery Baptist Medical Center for patients with internal derangements of the TMJ. By our evaluation, 94% are remarkably successful, 4% are marginally successful, 1% are not improved, and less than 1% are failures. On the basis of these experiences, we believe that the surgical technique of reconstructive arthroplasty and disk repositioning has a definite place in the treatment of patients with internal derangements of the TMJ.


The need to use an arbitrary face-bow when remounting complete dentures with interocclusal records.

The need for the arbitrary face-bow during finished denture remount is demonstrated and advocated. The face-bow transfer allows a more accurate arc of closure on the articulator when the interocclusal records are removed and the articulator is closed.


Antecedents of dental fear.

Early dental experiences were described in essay form by 225 college students reporting either "high" or "low" fear of dentistry. Antecedent factors which appeared to differentiate the two groups most clearly included pain experiences and dentist behaviors. Results were interpreted as supportive of a social-learning model of dental fear acquisition and their implications for dental training and practice were discussed.


The quality of radiographs used in the pretreatment review of dental claims.

The purpose of the study was to assess the quality of radiographs accompanying claims submitted for pretreatment review, and to determine the relative importance of radiograph quality in dental consultants' decisions regarding the necessity and appropriateness of crown services. Findings indicate that: 1) the technical quality of radiographs in the sample is adequate for most criteria; and 2) radiograph quality, number, and type of film submitted do not explain much of the variation in disagreements between the direct and indirect assessments of crown services. The most important radiograph variables influencing pretreatment review decisions appear to be the number of periapical films submitted for review, and the density/contrast of the radiographs.


The public health interest in assessment for orthodontic treatment.

In dental public health care programs the occlusion of the teeth is of interest from several different viewpoints: clinical treatment, screening for treatment need and priority, resource planning, and funding. Aspects of occlusion which are of interest are occlusal features, the need for treatment, the difficulty of treatment and the social factors affecting the practicability of treatment. Most of the interested parties are particularly concerned with the need for treatment--an area where objective assessment is not possible. Several methods of assessment of treatment need have been devised. Many of these are reasonably objective methods of assessing occlusal features, but involve the subjective concept that occlusal variation needs correction. In the absence of an objective measurement of treatment need, screening programs could be carried out by personnel who have training in the use of indices but not in clinical orthodontics. Resource planning, however, needs a knowledge of clinical orthodontics to determine types and relative difficulties of treatment required. For public health purposes there is a need for an assessment which would include the etiological factors of malocclusion which govern the difficulty of treatment, and the social factors governing the practicability of treatment.


Paternal age effect in fibrodysplasia ossificans progressiva.

Analysis by the method of Smith (1972) of birth order and parental age data collected from 38 of 42 patients with fibrodysplasia ossificans progressive shows a significant paternal age effect. This finding among the sporadically occurring cases would support the proposition that this condition usually arises as a new dominant mutation.


Pediatric adenoidectomy and tonsillectomy--personal viewpoints.

A report on experience with adenoidectomies, tonsillectomies, and adenotonsillectomies carried out at the Hospital for Sick Children, Toronto in the period 1968-75. Operations were performed on 25,443 patients during this period. Reasons for the reduction in T&A operations in recent years are considered, and views are expressed regarding when such operations are indicated, age of patient for surgery, the allergic child, cleft palate patient, the presence of quinsy, cardiopulmonary changes, subluxation of cervical spines, anesthesia, and postoperative care and complications.


Reproducible metastatic growth of K-562 human myelogenous leukemia cells in nude mice.

A reproducible metastatic growth of K-562 human myelogenous leukemia cells occurred in immunodeficient athymic (nude) mice. Although previous studies have shown that K-562 cells grow as local subcutaneous myelosarcomas which continuously release leukemia cells into the systemic circulation in adult mice, metastases were not observed. However, the subcutaneous "priming" of newborn nude mice resulted in the metastatic proliferation of leukemia cells in the lungs, kidneys, brain, and lymph nodes. Three sc injections of 5 X 10(6) K-562 cells on days 1, 7, and 14 of life produced metastases in 51% of the mice. When the initial series of injections was followed by iv injections on days 35 and 42, the incidence of metastases increased to 67%. Karyotypes demonstrated that the tumor cells retained the same human chromosome markers as those in the human patient and tissue culture. These procedures may provide a model for study of the mechanisms of metastases and for chemotherapeutic and immunotherapeutic trials against metastases of neoplasms of human origin.


Mitogen-induced changes in the fluorescence polarization of fluorescein in normal human lymphocytes: a membrane event?

The fluorescence polarization of human lymphocytes undergoing fluorescein fluorochromasia was measured in a system in which antifluorescein IgG was used to quench the extracellular emission of fluorescein leaked from the cells. The polarization values obtained from control cells were similar to those obtained by other investigators, as was the decrease in polarization in response to exposure to phytohemagglutinin or concanavalin A. However, the changes in polarization resulting from mitogen stimulation depended on the amount of antibody used, which suggests an increased or altered permeability of the plasma membrane to fluorescein efflux rather than a cytoplasmic reorganization.


Electron microscopic analysis of lymph node cellular activity in Hodgkin's disease.

Five hundred and two cells, selected at random within the pretreatment-involved lymph nodes of patients with the nodular sclerosis type of Hodgkin's disease, were analyzed by electron microscopy for in vivo subcellular activity and intercellular interaction. Subpopulations of neoplastic cells and of lymphocytes were recognized by ultrastructural criteria. Neoplastic cells displayed definite sequences of cell maturation, whereas lymphocytes displayed definite sequences of cell activation. Active lymphocytes were most often found apposed to the more active of the neoplastic cells, and the nuclei of such apposed lymphocytes displayed a progressive preferential asymmetry of distribution of active DNA templates into that half of the lymphocyte nucleus closest to the neoplastic cell. Such close apposition of active polysomal lymphocytes to neoplastic cells may correlate with increased patient survival in Hodgkin's disease.


Induction of retrovirus particles in human testicular tumor (Tera-1) cell cultures: an electron microscopic study.

The Tera-1 and Tera-2 cell lines, established from germ-cell tumors of the human testis, were examined by electron microscopy for particles with the morphology of retroviruses. Extracellular and budding particles were observed at low frequencies only in cultures of Tera-1 cells that had been treated with 5-iodo-2'-deoxyuridine and dexamethasone. No particles were detected in untreated cultures of Tera-1 cells or in any preparations of Tera-2 cells.


Geographic patterns of renal cancer in the United States.

Mapping of the geographic distribution of renal cancer mortality for groupings of U.S. counties revealed clustering of elevated rates among white males and females in the upper north-central part of the country. Throughout the United States, mortality increased with urbanization for males only, whereas rates for both sexes showed positive correlations with socioeconomic status. The major correlate of the cancer rates was ethnicity. Mortality was elevated in counties with high percentages of residents of German, Scandinavian, and especially Russian descent. Ethnic susceptibility appears to account, at least partly, for the regional clustering of kidney cancer and may provide leads to environmental determinants.


Odontomas in Peromyscus leucopus.

A colony of Peromyscus leucopus was established 15 years ago from animals trapped in the deciduous forest at Argonne National Laboratory, Argonne, Illinois. A roentgenographic survey of the skeletons of 189 of these untreated animals dying during a 13-month period disclosed 48 odontogenic growths in 21 of the mice. These growths were diagnosed on histopathologic examination as complex odontomas, the incidence of which was higher in males than in females. In this relatively small sample, these benign tumors appeared to be associated with youth rather than old age.


Long-term effects of neonatal estrogen treatment on mitogen responsiveness of mouse spleen lymphocytes.

Neonatal female NMRI mice were given injections of olive oil (controls) or daily doses of corticosterone (10 micrograms), 17 beta-estradiol (10 micrograms), or diethylstilbestrol (DES) (0.01, 0.1, 1, or 5 micrograms) for the first 5 days after birth. The 5-micrograms dose of DES resulted in a persistently reduced in vitro mitogen response to concanavalin A or bacterial lipopolysaccharide of spleen lymphocytes from 6-, 10-, and 18-week-old or 17-month-old females. DES injections from day 6 through day 10 did not influence the later mitogen response. Treatment of ovariectomized 10-week-old females with 5 micrograms DES for 5 days resulted in a tendency to a reduced mitogen response (not statistically significant) 24 hours after the last DES injection. Four weeks later, the mitogen response was the same in experimental and control females. Different possible mechanisms for the persistent effect on the mitogen response are discussed. Neonatal DES treatment not only resulted in persistent changes in the cervicovaginal epithelium and in the hypothalamic-pituitary gland control system but also in the spleen lymphocyte mitogen response. The altered mitogen response should be a stimulus for a detailed analysis of the immune system in women exposed to DES during fetal life, some of whom develop later in life clear cell adenocarcinoma of the uterine cervix and vagina.


Inhalation bioassay chemistry--Walton Horizontal Smoking Machine for inhalation exposure of rodents to cigarette smoke.

Studies of experimental tobacco smoke carcinogenesis have suffered from the lack of a conveniently available and well-characterized device for exposing animals to tobacco smoke for inhalation. The Walton Horizontal Smoking Machine, a commercially available system designed to expose up to 20 mice to the smoke of a single cigarette, may fulfill this need. This system produced a uniform smoke aerosol of predictable concentration and appropriate composition for cigarettes with high delivery of nicotine (40 mg total particulate matter, 2.6 mg nicotine, and 17 cm3 carbon monoxide per cigarette) and with low delivery of nicotine (30 mg total particulate matter, 0.3 mg nicotine, and 17 cm3 carbon monoxide). In this experiment C57BL and DBA/2Bd strains of mice were used. Limitations of the concept of exposing animals to standing smoke were defined.


Spontaneous regression of Friend murine leukemia virus-induced erythroleukemia. IV. Effects of radiation and athymia on leukemia regression in mice.

The spontaneous regression of the erythroleukemia induced by the regressing Friend murine leukemia virus (F-MuLV) complex was inhibited by irradiation of the animals prior to F-MuLV inoculation. This inhibition was proportional to the dose of radiation used. Treatment of the mice with the bone-seeking isotope 89Sr also inhibited erythroleukemia regression, which implicates the same effector mechanisms involved in the resistance to F-MuLV or F-MuLV-induced immunosuprression. Erythroleukemias induced in athymic nude mice by the regressing F-MuLV complex exhibited higher rates of lethality than did the leukemias in heterozygous or homozygous thymus gland-containing controls. These data suggested the involvement of the immune system in erythroleukemia regression and the specific participation of thymus cells and an 89Sr-susceptible function, perhaps marrow-dependent cells, in the process of regression.


Transmission electron microscopy of fetal rat brain cells during neoplastic transformation in cell culture.

Fetal rat brain cells were investigated by transmission electron microscopy during neoplastic transformation in long-term cell culture. Before transfer of the cells to culture, BD IX rat fetuses were treated with a single transplacental pulse of N-ethyl-N-nitrosourea (75 micrograms/g body wt) on the 18th day of gestation. During the early stages (3--4 mo), both glia-like and neuron-like cells were present in the culture, and after 2 months they formed complex aggregates ("nodules"). In contrast, corresponding secondary control cultures consisted of flat, epithelioid neural cells without neuron or astrocyte differentiation. After 3 months, cells with neuron morphology gradually disappeared. Some of the remaining cells contained many autophagosomes. After 5 months, rapid proliferation of rather homogeneous, glia-like populations was accompanied by reduction of microfilament bundles and microtubules, as well as atypical nuclei. Ability to form tumors upon sc implantation into syngeneic hosts was not observed until about 3 months later.


Induction of hepatic tumors in rats by senkirkine and symphytine.

The carcinogenicity of the pyrrolizidine alkaloids senkirkine and symphytine was studied in male inbred ACI rats. Animals were divided into 3 groups: Group I received ip injections of freshly prepared senkirkine at a dose of 10% of the median lethal dose (LD50) twice weekly for 4 weeks and then once a week for 52 weeks. Group II received ip injections of symphytine at a dose of 10% of the LD50 by the same injection schedule as in group I. The control group was given ip injections of a 0.9% NaCl solution following the same injection schedule as in experimental groups. All group I rats survived for more than 290 days after the start of injections, and 9 of 20 rats developed liver cell adenoma. All group II animals survived for more than 330 days after the start of injections. Of 20 rats, 4 had liver tumors, 3 had hemangioendothelial sarcomas, and 1 had liver cell adenoma. The hemangioendothelial sarcomas showed metastasis in the lungs of 2 rats. The control group had no liver tumors.


Inhibition of promutagen activation by the antioxidants butylated hydroxyanisole and butylated hydroxytoluene.

Butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) exhibited antimutagenic activity in the Salmonella typhimurium reversion test. Both BHA and BHT reduced reversion induced by chemicals requiring metabolic activation for effectiveness. However, they did not affect reversion induced by direct-acting mutagens. These results suggested that BHA and BHT may inhibit the metabolic activation processes and demonstrated that the S. typhimurium reversion test may be used to identify inhibitors of the neoplastic process.


Effect of cadmium exposure on primary tumor growth and cell-mediated cytotoxicity in mice bearing MSB sarcomas.

In vivo MSB tumor growth and cell-mediated cytotoxicity (CMC) to MSB tumor cells in vitro were studied in male C57BL/6 mice exposed to 0, 3, 30, or 300 ppm Cd as CdCl2 in their drinking water for 21 weeks prior to and during tumor growth. CMC was assessed on days 5, 12, and 19 post injection with the use of both a 51Cr release assay and a 51Cr post-label assay. Cd exposure significantly inhibited the growth of MSB tumors in vivo and enhanced the levels of CMC in the tumor-bearing hosts. Peak levels of CMC on day 12 post tumor injection were significantly increased in Cd-exposed animals. However, whereas the inhibition of tumor growth was directly dependent on the dose of Cd, the enhancement of CMC was inversely related to dosage. These data suggested that other mechanisms in addition to increased CMC were involved in tumor growth inhibition. Possible factors such as direct inhibition of tumor growth by Cd and decreased serum blocking levels in Cd-exposed animals are discussed.


Interaction of retinoic acid and 3-methylcholanthrene on the fine structure of mouse prostate epithelium in vitro.

The effects of 3-methylcholanthrene (MCA) and retinoic acid (RA) on the fine structure of AKR mouse prostate epithelium in organ culture were correlated with changes in cell proliferation. In intact glands before explantation, the epithelial cytoplasm showed concentric flat or globular cisternae of endoplasmic reticulum in both supranuclear and basal areas, a well-developed Golgi complex, secretory vesicles, and numerous microvilli at the luminal surface. After explantation, the cytoplasmic organelles, particularly the endoplasmic reticulum, regressed and tonofilaments appeared. The regression was largely prevented by RA. MCA induced considerable epithelial hyperplasia and squamous metaplasia. The fine structure of the newly formed cells revealed a complete loss of endoplasmic reticulum, Golgi apparatus, secretory vesicles, and microvilli, with the appearance of bundles of tonofilaments and a striking increase in the number of desmosomes. Administration of RA to explants pretreated with the carcinogen partially reversed the hyperplasia and squamous metaplasia. The tonofilaments disappeared and the number of desmosomes greatly decreased, whereas endoplasmic reticulum, Golgi complex, secretory vesicles, and microvilli were largely reestablished. Planimetric measurements of the alveolar epithelium showed that the squamous transformation and its partial reversal by RA coincide with the rise and decline of epithelial hyperplasia. The data suggest that the restoration of secretory differentiation by RA was responsible for the initial breakdown of the hyperplastic epithelium, whereas the lowering of DNA synthesis by RA prevented further hyperplasia and kept cell replication within normal limits.


Local tumor regression after intralesional injection of croton oil.

Intralesional administration of emulsified croton oil into established syngeneic transplants of murine firosarcoma no. 1023 caused complete regression of the injected tumors in C3H mice without recurrence during the period of observation. In Sewall Wright strain 2 guinea pigs, in contrast to BCG cell wall vaccine which eradicated regional lymph node metastasis as well as dermal transplants, croton oil treatment only delayed the development of metastatic disease despite the fact that the injected skin tumors did not recur. 12-O-Tetradecanoylphorbol 13-acetate (TPA), the active principle of croton oil, incorporated in mineral oil droplets in aqueous suspension, caused regression of murine tumors when injected intralesionally. Aqueous suspensions of TPA failed to eliminate the tumors. Our results suggest that tumor regression induced by croton oil of TPA emulsions was due to indiscriminate destruction of the injected tissue.


Adenosis-like lesions and other cervicovaginal abnormalities in mice treated perinatally with estrogen.

Female mice from three inbred strains (BALB/cCrgl, C3H/Crgl, and C57BL/Crgl) and one noninbred stock [RU:NCS (RU)] were treated perinatally with estradiol benzoate (EB), diethylstilbestrol (DES), or sesame oil and were killed on postnatal days 30--36. A combined prenatal and neonatal regime of EB injections resulted in the abnormal presence of columnar epithelium in the vaginal fornices of some of the mice from each strain or stock. The same epithelial abnormalities were also present in the vaginal fornices of 30-day-old RU:NCS(RU) mice that had been treated only neonatally with EB or DES. The incidence of these lesions was 40--67% in the mice treated prenatally and neonatally with EB, 68% in the neonatal EB treatment group, and 100% in the neonatal DES treatment group. The columnar cells were arranged either as single layers in areas of the fornical lining epithelium or as glandlike or cystic structures in the subepithelial stroma. No cells of this type were detected in any of the samples from sesame oil-inoculated control mice. No comparable epithelial lesions were detected in the common cervical canal of the perinatally estrogen-treated animals, but this treatment consistently resulted in gross structural abnormalities at this site.


Use of hamster hepatocytes to metabolize carcinogens in an in vitro bioassay.

Adult Syrian golden hamster hepatocytes were shown to have a high capacity to metabolize carcinogens, such as diethylnitrosamine, 2-nitrofluorene, and 4-aminoazobenzene, to a form that transforms mammalian cells. The addition of hepatocytes to the hamster embryo cell transformation system extends its range of usefulness for detecting carcinogens that require metabolic activation.


Impairment of red blood cell deformability by tumor growth.

Red blood cell deformability is a major determinant of capillary blood flow. In mice with L1210 leukemia and with Lewis lung carcinoma, red blood cell deformability was significantly decreased during tumor growth. In mice with L1210 leukemia, deformability was significantly decreased by day 5 after transplantation and progressively decreased through day 9. Terminally, red blood cell deformability returned to normal or above normal values. In mice with Lewis lung carcinoma, significant decreases in deformability were noted 21--28 days after transplantation and persisted throughout the remainder of the tumor course. Impaired capillary blood flow, secondary to abnormal red blood cell deformability, is therefore associated with advanced cancer.


Translocation of the pre-synaptic complex formed upon DNA uptake by Streptococcus sanguis and its inhibition by ethidium bromide.

Donor DNA in its initially bound, single-stranded form exists in a chromosomally-unassociated complex where it is resistant to exogenous DNase I but sensitive to micrococcal nuclease. Most of the complexes are readily recuperable from the supernatant of recipients converted into spheroplasts. Subsequent to formation of this superficially located complex, donor DNA progressively associates with the recipient chromosome into which it is eventually integrated. Treatment of recipients with ethidium bromide at various times after initial DNA binding almost immediately halts translocation of whatever donor material is not yet synapsed with the chromosome. On the other hand, donor DNA that has already synapsed experiences no difficulty in becoming genetically integrated. Some degradation occurs to DNA that fails to undergo translocation as a result of ethidium bromide treatment, the acid-soluble products appearing in the culture medium. DNA in untranslocated complexes surviving treatment is not appreciably different in single-strand length from that in untreated complexes. When these surviving complexes are isolated from a cell lysate, the contained DNA can be shown by spectrofluorometry to have bound the drug.


The structure of the phi 80d3 ilv+ Su+7 transducing phage and the origin of its Su+7 tRNA-gene containing fragment.

The Bam HI, XhoI, and EcoRI sites of the transducing phage phi 80d3Su+7ilv+ are located. The 1.2 x 10(6) MD EcoRI fragment which, when cloned, contains tRNAAsp and expresses the mutant tRNATry gene, Su+7, and which also relaxes control of stable RNA synthesis is found immediately adjacent to the rrnC region. Its tRNA genes, tRNAAsp and tRNATry, are transcribed in the same direction as the ribosomal RNA genes, though no mature rRNA subsequences are on the fragment. This fragment also exists as such in another F-prime factor derived from the same Hfr host, and therefore presumably also in the Hfr chromosome itself. It is composed of about half ordinary chromosomal and half F DNA sequences, the latter from the gamma-delta region of F. The advantages of a novel mapping method used are discussed.


An evaluation of Corynebacterium parvum during remission maintenance therapy in pediatric patients with acute lymphoblastic leukemia.

The biologic impact and clinical toxicity of Corynebacterium parvum administered at a dose of 5 mg/M2 by intravenous or subcutaneous routes were evaluated in 18 children receiving combination chemotherapy for maintenance of acute lymphoblastic leukemia (ALL) in remission. Several nonspecific immunologic and hematologic parameters were evaluated. Patients were also monitored for changes in cutaneous sensitivity to histamine. No changes in any parameter were observed in patients after only one course of C parvum injection. However, after 6-10 courses, glass-adherent peripheral blood leukocytes of C parvum-treated patients augmented the response of PHA-stimulated autologous lymphocytes. In all nine patients studied who received C parvum injection subcutaneously for at least six months, there were significant increases in the mean bone marrow myelocyte-erythrocyte (ME) volumes compared to pretreatment values. These results suggest that periodic evaluations are desirable in patients receiving repeated administration of C parvum, since changes in immunologic and hematologic responses may be demonstrable only after several injections. In contrast to the reported experience in adults, subcutaneous C parvum administration children was not well tolerated, whereas intravenous infusion was generally well tolerated.


L-asparaginase used with cytosine arabinoside in treatment of childhood acute lymphocytic leukemia refractory to vincristine and prednisone.

Eleven patients with acute lymphocytic leukemia in relapse were treated with L-asparaginase and cytosine arabinoside (1-beta-D-arabinofuranosylcytosine) in induction therapy and the same drugs plus cyclophosphamide in maintenance therapy. Three patients had complete remissions lasting 6, 16, and 78+ weeks. One patient experienced partial remission and four had decreased bone marrow or peripheral blasts but were not clinically improved. The responses, which were brief, lasted 1-16 weeks with one exception of 78+ weeks. Four patients had allergic reactions to L-asparaginase that were unpredictable with assays of antibodies against L-asparaginase.


An autopsy study of eye involvement in acute leukemia of childhood.

The eyes of 60 children who had died of acute leukemia between 1968 and 1977 at the Children's Hospital Medical Center have been examined pathologically. An attempt has been made to relate eye findings to the state of the systemic disease at the time of death. Eight of the 60 patients had leukemic retinal infiltrates and all eight had fulminant disease with terminal leukocyte counts over 100,000 per cubic millimeter and a high percentage of "blast" cells. Twenty-six patients (43%) had leukemic infiltration of the choroid that was inapparent clinically. Choroidal involvement was not correlated with high terminal leukocyte counts but was invariably associated with widespread infiltration of other organs. Four patients had optic nerve involvement; all four had coexistent meningeal leukemia. Isolated retinal hemorrhages could not be correlated with other parameters of the leukemic process.


Jogger's heat stroke.

Two patients developed heat stroke following jogging. Transient disturbance of cerebral function was the most dramatic clinical feature. Although haemorrhagic complications were not seen, marked changes in the haemostatic system occurred with both thrombocytopenia and a reduction of clotting factors synthesised by the liver. No evidence of disseminated intravascular coagulation was found. Heat stroke must now be added to the list of jogging hazards.


The effect of counselling on compliance-failure in patient drug therapy.

This paper reports the results of a study to determine the effects of counselling on patient compliance-failure in expected drug therapy. In patients discharged from acute general medical wards, counselling reduced compliance-failure for both patient non-compliance and error by approximately 40%. It was especially effective in reducing compliance-failure due to non-compliance where reasons were either the occurrence of adverse drug effects or patient belief that therapy was ineffective, and patient-error where this resulted from misinterpretation. The use of drug calendar cards did not minimise the incidence of non-compliance but was effective at reducing error, especially with Polynesian patients. It is concluded that prescribing clinicians can reduce compliance-failure by active drug-counselling.


Current trends in the treatment of rheumatoid arthritis in general practice.

Questionnaires were sent to 180 randomly selected general medical practitioners in the Auckland area, to determine the source of prescribing information and current drug prescribing pattern in general practice, for the treatment of rheumatoid arthritis. Medical journals were the main current source but postgraduate seminars and lectures were the preferred source of prescribing information. Aspirin remains the drug of first choice in the treatment of rheumatoid arthritis and along with indomethacin, phenylbutazone and prednisone (10 mg daily), considered to be more effective than the newer propionic acid derivatives. Enteric coated aspirin was preferred in the patient with an active peptic ulcer. Almost all of the replying doctors, endeavoured to give their patients an explanation as to the underlying nature of their disease and treatment, but had little confidence that they would comply with the therapeutic instructions.


The silent ovary: a five year survey of cancer of the ovary at the Hutt Hospital 1973-1977.

Cancer of the ovary is the leading cause of death from gynaecological cancer. Forty-six cases are reported to re-emphasise certain features. These include the short history and the high mortality rate regardless of what treatment is used. Whereas improvement has occurred in the treatment of cancer of the corpus and the cervix, there has been no improvement over two decades in cancer of the ovary. The moral of this tale, is to advise your women folk to avoid cancer of the ovary.


The pathology of hysterectomy specimens.

Six hundred and twenty-one hysterectomies were performed at National Women's Hospital, Auckland, during 1975. Abnormal vaginal bleeding was the clinical indication in 50.72% of the cases. Fibroids, pelvic mass, prolapse, stress incontinence and cervical neoplasia were the indication for 45.88% of the cases. Total hysterectomy was performed in 618 (99.5%) patients whilst sub-total hysterectomy was done in only three cases. Histopathological studies revealed that 567 (91.30%) specimens were pathological and there was multiple pathology in 55.87% of the specimens. Leiomyomas were present in 278 cases (44.76%); microleiomyomatosis in 178 specimens (22.66%); endometrial hyperplasia in 139 specimens (22.33%) adenomyosis in 87 cases (14.00%); malignant diseases in 76 cases (12.23%); and endometriosis in 40 specimens (6.44%). There were no histological abnormalities in 54 specimens, 8.69% of this series.


Anorexia nervosa in a male: comment and illustration.

Attention is drawn to the possible diagnosis of anorexia nervosa in young males with weight loss. The symptoms and signs are described, along with the setting in which the condition may develop. These points are illustrated by reference to a recently treated case. The poor prognosis of anorexia nervosa in males is emphasised.


Complications from prolonged catheterisation prior to prostatectomy.

This paper studies 46 patients with urinary retention who came to prostatic surgery some time later. With prophylactic antibiotics used in cases with urinary infection the risk of surgery is not increased, despite an average period between catheterisation and surgery of one month.


Pyloric obstruction caused by aspirin: case report.

A case of pyloric obstruction caused by ingestion of enteric-coated aspirin tablets is presented. The patient was predisposed by previous pyloric stenosis. A barium meal study was diagnostic. The patient later had a massive gastro-intestinal haemorrhage requiring surgical repair. The hazards of aspirin ingestion in such a patient are discussed.


The Northland Health Scheme.

The Northland Health Scheme, proposed by the Special Advisory Committee on Health Service Organisation (Sachso), is about to become a reality. On 20 February 1978 cabinet approved the setting up of a steering committe in Northland to propose a Health Board structure, establish further working parties to consider local aspects of the scheme, initiate the formation of service development groups, assist SACHSO in developing legislation, and take any other steps that seemed appropriate. The chairman of this committee was named on 1 March and others who have agreed to serve are listed in the New Zealand Medical Journal of 22 March (News, 1978). It is now, therefore, an appropriate moment to scrutinise carefully what is proposed and the principles that underlie the proposals.


A study of asthma in a Dunedin suburban area.

Asthma was reported by 6.2 percent of 2347 inhabitants of a Dunedin residential area. Symptoms occurred within the past two years in 4.2 percent. In this group the majority showed evidence of atopy by skin reactivity and elevation of serum immunoglobulin E. Airways obstruction was detected by spirometry in 62 percent and 56 percent demonstrated increased bronchial reactivity to histamine aerosols. Less than half used bronchodilator aerosols for relief and only 18 per cent were treated with prophylactic disodium cromoglycate.


Hospital admissions for wheezing in Polynesian children.

The purpose of this study is to establish a baseline of information about pre-school Polynesian children hospitalised with wheezing attacks. During a one year study period at Wellington Hospital, 19 percent of the acute paediatric admissions under five years were Polynesians with wheezing respiratory disease. Seventy percent of these admissions were in children under 18 months of age, and 38 percent of the children were readmitted during the year. These and other variables are compared to European children hospitalised with wheezing. We conclude that young Polynesian children in New Zealand are especially prone to a different pattern of asthma from European children.


Geographic distribution of peptic ulcer disease in Western Samoa.

A survey of peptic ulcer disease in Western Samoa is described. As compared with New Zealand experience, an unusually high prevalence of peptic ulceration is documented. A remarkable and significant variation in the geographic distribution of cases is reported. Regions of high prevalence were significantly associated with disease onset at an earlier age and with increased frequency of a family history of ulcer disease. It is concluded that this genetic predisposition is unlikely to sufficiently account for the regional localisation of cases observed and environmental causes are under study.


Prognosis of completely healed gastric ulcer.

Eighty patients with chronic gastric ulcer, shown to have complete healing by gastric photography, were followed for 18 months to nine years. Ulceration recurred in 24, always at the site of the original ulcer, the majority (14) of relapses occurring within 12 months. Those with recurrent ulcers were more likely to show delayed healing of their initial ulcer, than the ulcers not shown to recur. At two months, this was statistically significant (P = 0.004) and even more so at three months (P = 0.004). Recurrences were more frequent in males (P = 0.09). There were no differences in ulcer site or size compared with those ulcers not known to have occurred. The appearance of complications such as perforation, haemorrhage, or malignancy was rare after complete healing.


The passive hamstring stretch test: a comparison of clinical estimates with tension gauge measurements.

A comparison of the clinical estimate of the available passive stretch in the hamstring muscles is made against the changing tension in a spring gauge, as the leg is raised. It was found that the angle at which rotation was palpable in the contralateral anterior superior spine occurred after there was a sharp rise in the tension measurements. The spring gauge was incorporated in a pulley system which allowed the leg to be pulled up and the tension readings were taken at 5 degrees increments of raise. Comparison of the clinical estimates with the tension gauge measurements show the latter to be a more reliable and objective research tool.


An assessment of vulval pigmentation.

Thirty-five vulvectomy specimens were obtained from post-mortem material and studied to assess the distribution of melanin pigment. The information obtained was compared with the melanin distribution in melanoma-in-situ and melanosis vulvae. A lesion had to be larger than 3mm before it was recognised clinically. Melanosis vulvae is but an exaggeration of the normal distribution of melanin pigment. Melanoma-in-situ, however, cannot be reliably distinguished from the benign causes of pigmentation on clinical grounds. The correct diagnosis can only be made histologically. Other causes of vulval pigmentation are also discussed.


Reticuloendothelial neoplasia of the female genital tract.

Twelve patients thought to have gynecologic tumors subsequently were found to have lymphoma or leukemia. Eleven tumors involved the genital organs; one involved the retroperitoneal pelvic lymph nodes. A lymphoma originated in the genital tract in 7 patients, and secondary involvement occurred in 2 patients. One patient with a previously treated lymphoma and 1 with leukemia in remission developed ovarian tumors as the first sign of relapse. The difficulty in diagnosis, need for appropriate treatment, and prognostic importance of the genital organs affected are discussed.


Trismus after injection of local anesthetic.

Persistent pain at the site of injection is the most common complication of local anesthesia in the oral cavity. The complication of trismus after local anesthetic injection is rare and may be prevented by the use of short needles for maxillary posterior injections, and by the avoidance of multiple injections in  a short period time. Once trismus develops, its progression to chronic hypomobility and fibrous ankylosis may be prevented by the early institution of treatment consisting of heat, analgesics, muscle relaxants, and exercises.


Jawbone cavities and trigeminal and atypical facial neuralgias.

The possible role of dental and oral disease in the etiology of idiopathic trigeminal and atypical facial neuralgias has been examined. Among thirty-eight patients with idiopathic trigeminal neuralgia and twenty-three patients with atypical facial neuralgia, there was in nearly all instances a close relationship between pain experienced and the existence of cavities in alveolar bone and jawbone of the patients. The cavities were at the sites of previous tooth extractions and, although at times more than 1 cm. in a given diameter, were usually not detectable by x-rays. A new method for their detection and localization was developed empirically, based on the observation that peripheral infiltration of local anesthetic into or very close to the bone cavity rapidly abolished trigger and pain perception by patients during persistence of the anesthetic action. Histopathologic examination of bone removed from cavities by curettage revealed, in both idiopathic trigeminal and atypical facial neuralgias, a similar pattern characterized by a highly vascular abnormal healing response of bone. Some lesions presented a mild chronic inflammatory (lymphocytic) infiltration. Preliminary microbiologic studies of material from the walls of the cavities showed the existence within them of a complex, mixed polymicrobial aerobic and anaerobic flora. Treatment consisted of vigorous curettage of the bone cavities, repeated if necessary, plus administration of antibiotics to induce healing and filling-in of the cavities by new bone. Responses of patients to the above treatment consisted of marked to complete pain remissions, the longest of which has been for 9 years. Complete healing leads to complete and persistent pain remissions. It was concluded that in both idiopathic trigeminal and atypical facial neuralgias, dental and oral pathoses may be major etiologic factors.


Dental management for children with chronic renal failure undergoing hemodialysis therapy.

Patients with chronic renal failure who are undergoing hemodialysis therapy demonstrate problems of significant importance for dental treatment. A case is presented in which secondard hyperparathyroidism, resulting from renal failure and hemodialysis, was noted in a child. Other relationships between renal failure, hemodialysis, and dental care were also presented.


Cold agglutinin disease. Report of a case.

Cold agglutinin disease is an autoimmune hemolytic anemia with varying causes. Two major types are recognized, with different clinical manifestations. Cold agglutinins are circulating antibodies capable of erythrocyte agglutination. However, the reaction is readily reversible. Treatment of the disease is variable. A case is presented to illustrate that minor oral surgical procedures are feasible, provided the proper precautions are taken.


Simultaneous presence of partial anodontia and supernumerary teeth.

The literature is reviewed and three cases of simultaneous presence of partial anodontia and supernumerary teeth are reported. In all three cases the abnormality involved both the maxilla and the mandible. The role of the panoramic radiograph in the detection of rare cases of this kind is emphasized and illustrated.


Ultrastructure of a plasma-cell myeloma in the mandible.

Tumor cells exhibited large amounts of rough endoplasmic reticulum arranged in a lamellar pattern, large numbers of mitochondria with a perinuclear distribution, and a prominent Golgi complex, but only a small number of immunoglobulin granules. No crystalline structures of immunoglobulins were observed. Nuclei exhibited patchy condensation of chromatin and large nucleoli. The ultrastructural features suggest that this case could be a "resecretory" myeloma.


Scanning electron microscope study of a new irrigation method in endodontic treatment.

The effectiveness of a newly developed perforated endodontic irrigation needle, with its distal aperture sealed, was compared to conventional endodontic irrigation procedures. In all instances 5 percent sodium hypochlorite was used since the delivery system, rather than the irrigant, was being evaluated. A base line group in which all soft tissue was described was also included. The results indicate that the perforated endodontic irrigation needle is a very effective instrument for the cleansing of instrumented root canals.


Clinical and radiographic study of dens invaginatus.

After a determination of the frequency of dens invaginatus by means of radiographic observations, various problems of its identification are discussed. The 188 teeth showing a distinct loop-shaped invagination apically on the radiograph were studied for the presence or absence of caries and periapical lesions. It was demonstrated that periapical lesions caused by caries are mostly due to interproximal caries and that the frequency of periapical lesions caused by caries in the dens invaginatus area was less than previously reported. Comments are made on the dens invaginatus cases having periapical lesions without caries and the parameters for future studies.