[Determination of the most favorable impulses in oral irrigation using a new device]. The present paper discusses the question of the most favorable kind of impulsing the flow liquid in oral irrigation. A pulsation synchronous with the user's heart rate is considered optimal. The utilization of electron timing components which operate solenoid valves offers the possibility of securing (without complicated measuring and controlling systems) a synchronization of the pulsations of the water flow with the patient's heart rate which is sufficient for practical purposes since an acceleration of the blood flow is primarily achieved by removing the venous stasis.


[Methods and results of studies on scientific work organization at a stomatologic university clinic]. Starting from the importance of work studies aiming of scientific work organization in stomatology, the author points to a method for ergonomic complex analyses designed for the evaluation of factors which exert effects upon the functional unit of stomatologist/stomatological nurse, work place and patient. Certain selected results are reported in detail which have been obtained by means of this method in the framework of a pilot study performed at a university clinic of stomatology. The author indicates and discusses, for example, the results of a time study, the working position and posture, the kind of treatment, the noise exposure, the lighting, the room climate and the equipment of the work place. The possibility of listing some factors in the form of parameters of scientific work organization is illustrated by examples.


[The dental care for students].

[The dental care for students]. The progression of stomatological morbidity and the extent of the stomatological care of students were re-examined after two years, in a random sample of students previously studied. One third of the students who had been asked by post to come was re-examined; one third of them was not contacted because they had changed their residences and could not be reached by post; and one third did not respond. The high morbidity as well as the present situation of treatment requires an improvement in the stomatological care of the students by the territorial public health services of the town where they go to the university.


[Training methods suggested for the preservation of health and physical fitness of the dentist and his auxiliaries. 1. Heart and circulation training]. The performance of the cardiovascular system may be improved by endurance training. To avoid injuries due to overexertion, it is necessary to test regularly the individual physical capacity by appropriate methods. A practice-tried program of running exercises ensures, when taken consistently, a steady improvement of the cardiovascular fitness.


[Zinc oxide phosphate cement studies on the usefulness of Firmat]. The aim of the present investigations was to evaluate the Firmat zinc oxyphosphate cement in comparison with other brands, especially Adhesor normalhartend. The results obtained show that Firmat is a fast-setting phosphate cement which is not suited for polyhedral cavity linings. Time and material-consuming reworking is necessary. For temporary fillings, a temporary filling material should be used which is sufficiently solid, but easier to remove.


[Experimental x-ray diagnosis of osteosarcoma]. While using different methods of skeletal investigation, definite alterations were revealed in frequency of osteosarcomas under plutonium exposure (2.5 muC/Kg). The ratio of the corresponding values is 1:1,2:1,27:1,47. The highest incidence of osteosarcomas was noted in the complex roentgeno-morphological study (according to an extensive scheme of procurement of the osteomaterial) -- 39.8% In separate application of different methods of skeletal investigation the roentgenological method seems to be prefered: it determines more precisely the number of tumor nodes and the number of tumor-bearing rats, accordingly.


[Neoplastic variant of acute erythroblastotis--proerythroblastoma]. In two case of aorthochromatic anaemia refractory to treatment with granulocytopenia and thrombocytopenia without significant enlargement of abdominal viscera a hypothesis of uncontrolled proliferation involving proerythroblasts is put forward on the basis of bone marrow findings. This proliferation seems to be confined to a single focus-bone marrow, without evidence of peripheral dissemination. Profound dysplastic changes of proerythroblasts are suggestive of neoplastic growth.


Induction of ovulation.

Induction of ovulation. Ovulation has been induced by clomiphene citrate and human gonadotropins in infertile women. Clomiphene should be the first choice in anovulatory women with active ovaries as indicated by basic levels of estrogens in blood or urine, in women with post-pill amenorrhea even if their ovaries are quiescent and in women with functional abnormalities of the hypothalamus or pituitary. Human gonadotrophins should be used as a second alternative when clomiphene fails. It should also be used as a first choice in women with primary amenorrhea and quiescent ovaries and in women with gross anatomical changes in the pituitary or hypothalamus. If no result is obtained after two courses of gonadotropic therapy, further treatment should be reconsidered and the infertile couple reinvestigated.


Experimental aural barotrauma. Electrophysiological and morphological findings. The electrophysiological findings show a time and pressure related decrease in function of the CM and the N1 potentials. Sudden changes were correlated with tympanic membrane perforations. Some of the decreased function is accounted for by middle ear effusion and hemorrhages, reducing mechanically the transmission of sound energy through the middle ear. This was evidenced by an improvement of function when the fluids were removed. Remaining decreases in function were interpreted as a result of influences on the inner ear function or of undisclosed middle ear changes. No differences were noted in cochlear function between animals subjected to sustained or intermittent middle ear pressures. Neither were any morphological differences noted between these two groups in the middle or inner ear. The morphological middle ear findings correlated well with previous clinically and experimentally induced changes with increased/decreased middle ear pressure. The cochlear findings include the interesting observation of an intact round window membrane, a clear endolymph, and a normal Organ of Corti in all cases. Positive findings were a high frequency of hemorrhage, most commonly demonstrated in the scala tympani of the basal turn close to the round window. The origin of the hemorrhages could not be demonstrated with the present investigation. The hemorrhages often appeared to be related to the cochlear aqueduct. The occurrence of hemorrhage was clearly related to increased negative pressure, and the non-existence of hemorrhage was always related to either tympanic membrane perforations or low applied pressure. Further frequent findings were distention, collapse, and rupture of the inner ear membranes which must be interpreted with great circumspection due to the method used. Likewise, some of the pathological cochlear findings may be due to pathological conditions which are not necessarily related to induced middle ear pressure.


Morphological effects of rapeseed oil in rats. I. Short-term studies. Light microscopy of paraffin embedded and frozen sections, supplemented with electron microscopy, was performed on the heart muscle of young rats fed rapeseed oil in short-term experiments. It was confirmed that high levels of rapeseed oil, which contains erucic acid, produce severe lipoidosis of the heart muscle fibres within 10 days. An attempt was made to find out the lowest level of erucic acid in the rat diet to give rise to pathological fatty accumulation. Several frozen sections from each heart or serial sections in combination with electron microscopy were used for this evaluation. The level found to give rise to pathological fatty accumulation was about 2% by weight (w/w), while rats fed 1% erucic acid showed normal myocardium. No direct proof that erucic acid is of importance in human pathophysiology has hitherto been presented. It is concluded, however, that the similarity in reaction among the many species of experimental animals tested by different workers, as well as the basic metabolic disturbances demonstrated, are in strong favour of a similar effect in man.


Morphological effects of rapeseed oil in rats. II. Long-term studies. In long-term studies covering up to 160 days young Sprague-Dawley rats were fed diets containing 40 cal% of fat. The fat component consisted of either conventional rapeseed oil, or Canadian rapeseed oil low in erucic acid, or arachis oil. Myocardial fatty accumulation was demonstrated in light microscopic studies throughout the experiments in rats fed conventional rapeseed oil, but the number of fat droplets decreased with time. The controls fed arachis oil showed no fatty accumulation. In the rats fed conventional rapeseed oil focal myocardial lesions appeared after 40 days on the diet. These consisted of histiocytic infiltration, occurrence of macrophages, myolysis, proliferation of fibroblasts and finally scarring. Such foci were found widely spread in the myocardium of these rats. In the experimental groups given Canadian rapeseed oil from the cultivar Oro no histiocytic foci or scarring were observed. Small myocardial lesions were occasionally found in the control rats. These latter findings were observed on serial sections. It was concluded that this type of lesion is a "normal" finding. The number and size of the foci observed in animals fed conventional rapeseed oil (10% and 2% (w/w) erucic acid in the diet) indicate, however, that they have to be considered pathological under such circumstances. The pathogenesis of the myocardial alteration is discussed and it is concluded that the long-chain fatty acids are responsible. No direct proof has been presented that the described events are of importance in human pathophysiology, However, several circumstances pointing in this direction are discussed. It is concluded that on the basis of our present knowledge a pathological effect of erucic acid and its homologues in man cannot be excluded.


Morphological effects of rapeseed oil in rats. III. Studies in germ-free rats. The morphological effects on the myocardium of feeding rapeseed oil were compared in conventional and germ-free rats in short-term experiments (10 days). It was concluded that the fatty accumulation in the heart muscle cells occurring in rats fed rapeseed oil was not influenced by the presence or absence of a normal intestinal flora. In long-term experiments (80 days) under similar conditions, the myocardial effects of feeding germ-free rats with conventional rapeseed oil, rapeseed oil from the Canadian cultivar Oro very low in erucic acid, or arachis oil were studied in serial sections. Severe myocardial lesions developed in the group of rats fed conventional rapeseed oil, while in the other two groups the myocardium was completely normal. These results give no support to the theory that other factors than C22:1 acids in rapeseed oil are responsible for the myocardial lesions.


Electrocardiogram and renal concentrating capacity in rats fed a diet containing rapeseed oil. The functional effects of a diet containing rapeseed oil (40% of total energy intake) were studied in rats, starting at age 28 days. There were no effects on the electrocardiogram in spite of morphological changes in the myocardium. In 10 female rats the urine osmolality following 16 hours of dehydration was approximately 20% lower than in 10 control rats during the 9th, 10th and 20th week of the experiment. It is suggested that erucic acid in the rapeseed oil inhibits beta-oxidation of fatty acids in the kidney, thereby depriving the kidney of energy involved in sodium transport.


Observations on lipid composition with particular reference to cardiolipin of rat heart after feeding rapeseed oil. The influence of dietary rapeseed oil on the lipid classes and fatty acid pattern of rat heart homogenate and mitochondria has been investigated after feeding a diet with 9.8 weight- % erucic acid for 10 days and 1.4 and 2.6% erucic acid for 28 days. The rats treated with 9.8% erucic acid showed a significant increase in the triglycerides of the heart mitochondria. This tendency was much less pronounced in rats treated with 1.4 resp. 2.6% erucic acid. These results confirm those of other investigators. A slight increase in the cholesterol esters of the mitochondria could be seen in all the treated rats. The total phospholipids were decreased in the experiment with 9.8% erucic acid and slightly increased in experiments with 1.4 and 2.6% erucic acid. The concentration of phosphatidylcholine showed a tendency to increase and the concentration of phosphatidylethanolamine to decrease in the experiment with 9.8% erucic acid in the diet. The concentration of cardiolipin was mainly unchanged. In all experiments the triglycerides of the heart mitochondria showed a high content of erucic acid. The fatty acids of the cholesterol esters of the heart mitochondria were also influenced of dietary rapeseed oil but to a less extent than the triglycerides. The fatty acids of phosphatidylcholine, phosphatidylethanolamine and cardiolipin were all influenced by the dietary rapeseed oil, but the erucic acid seemed to have a specific affinity to cardiolipin. Cardiolipin of rat heart mitochondria was isolated and identified with gas chromatography and mass spectrometry. The isolated cardiolipin was found to contain 12 per cent erucic acid after feeding 9.8% erucic acid as rapeseed oil for 10 days. Similar results were obtained after feeding glyceryl trierucate for 5 days to rats. The incorporation of erucic acid into cardiolipin was followed by a corresponding decrease of linoleic acid. This observation is of great interest because the molecular structure of fatty acids in lipid molecules has a profound influence of the packing of these molecules in a bilayer. Since cardiolipin is a component of the inner membrane of mitochondria its high affinity for erucic acid might influence the normal function of the inner membrane of heart mitochondria.


Studies of the mode of action of erucic acid on heart metabolism. The effects of erucic acid on the oxidative metabolism of rat-heart mitochondria have been investigated using intact animals, perfused beating heart, isolated mitochondria and mitochondrial extracts. Feeding rats with a diet containing erucic acid was found to lead to a diminished ability of the isolated heart mitochondria to oxidize various substrates, in accordance with previous reports (Houtsmuller et al., Biochim. Biophys. Acta 218 (1970) 564). This effect was almost pronounced with palmitylcarnitine as substrate, in which case the rate of oxidation was decreased by more than 50% at such a low erucic acid content in the diet as 1.4% given over 2-4 weeks. Oxidation of palmitylcarnitine was also found to be inhibited when erucylcarnitine was added to isolated heart mitochondria from control animals, in agreement with earlier observations (Christophersen and Bremer, FEBS Lett. 23 (1972) 230; Biochim. Biophys. Acta 280 (1972) 506). The inhibition was accompanied by a decrease in the rate and extent of reduction of mitochondrial flavoprotein. Experiments with perfused beating rat-heart likewise revealed an inhibition of flavoprotein reduction, as well as nicotinamide nucleotide reduction, when erucate was added to the perfusing medium of the beating heart respiring with oleate--but not with octanoate--as substrate. These data together with those earlier published in the literature indicate that erucic acid may interfere with the enzyme system involved in the mitochondrial oxidation of long-chain fatty acids, probably at the level of acyl-CoA dehydrogenase. Kinetic data supporting this conclusion, obtained with extracts of rat-heart mitochondria containing the acyl-CoA dehydrogenase and electron-transferring flavoprotein system, are presented. The possible implications of these results for the known effect of dietary erucic acid in causing an accumulation of fat in the heart are discussed.


The role of myocardial membrane lipids in the development of cardiac necrosis. 1. The fatty acid composition of cardiac membrane lipids is influenced by age, sex, diet and other factors. 2. The relative amounts of various polyunsaturated fatty acids in cardiac lipids influence markedly the development of myocardial necrosis and mortality following overstimulation with isoproterenol. 3. The availability and metabolism of arachidonic acid may play an important role in regulation of cardiac metabolism.


Effect of cardioselective beta-blockade on heart function and chest pain in acute myocardial infarction. Systolic time intervals and the a/H ratio were recorded in 20 patients with uncomplicated acute myocardial infarction over a period of five days. The initial high heart rate and systolic blood pressure and the short PEP and ICT indicating a sympathetic overactivity were spontaneously normalized during the first week of infarction. LVET was reduced indicating a fall in stroke volume and the a/H ratio was unchanged at the high levels suggestive of elevated preload or LVEDP. In 10 patients with acute myocardial infarction and recurrent chest pain recordings on noninvasive parameters were made before and 30 min after intravenous injection of practolol. In addition, 7 patients with chest pain, classified as acute myocardial infarction, were given practolol. The average dose of practolol was 17.9 mg ranging from 5 to 30 mg. An almost immediate and pronounced relief of pain was observed in all patients and no signs of impaired left ventricular function appeared. The product of systolic blood pressure and heart rate was decreased by practolol and the PEP and the ICT were prolonged to normal values while no changes were seen in LVET and a/H ratio. On 126 occasions practolol was given in dosages ranging from 5 to 30 mg (mean 8 mg) to 75 patients with acute myocardial infarction and recurrent chest pain. A satisfactory pain relief was seen on 108 occasions. It is suggested that an inappropriate sympathetic overactivity is an important factor in provoking recurrent chest pain in acute myocardial infarction. Administration of the beta-adrenergic blocking agent practolol resulted in pain relief due to reduction of heart work and in severity of myocardial ischemia. The beta-blocking agent was well tolerated in the present study. Continuous beta-blockade during the whole hospital stay to patients with acute myocardial infarction seems to be a very attractive therapy in order to preserve the ischemic myocardium and limit the size of infarction.


The importance of mechanical performance for development of myocardial infarction in man. In studies using an experimental infarction as a model it has been shown that factors increasing myocardial oxygen consumption will increase the size of infarction, while factors reducing the oxygen consumption have the opposite effect. The presence of catecholamines might be most important. It is suggested that local release of noradrenaline from the sympathetic nerve endings in ischemic myocardium can induce vigorous contractions and deleterious ischemia and result in cellular necrosis. A retrospective study was performed in 81 patients hospitalized in Göteborg in 1964-1965 due to attacks of severe chest pain with no previous documented myocardial infarction. In 31 of these patients definite congestive heart failure was seen at hospitalization or developed later. During 10 years of follow up the mortality was 48 per cent and an acute myocardial infarction was found in 64 per cent of the patients without congestive heart failure. In patients with congestive heart failure the mortality was 42 per cent, and 6.4 per cent had an acute myocardial infarction. The poor mechanical performance and a lower myocardial content of noradrenaline of the failing heart might protect from the acute myocardial infarction and instead be predisposed to a slow degeneration, pump failure, and serious arrhythmias. Severe angina pectoris and congestive heart failure might represent opposite ends of the spectrum of ischemic heart disease with similar degrees of luminal narrowing of the coronary arteries.


Cell volume regulation in acute myocardial ischemic injury. Thin freehand slices of left ventricular papillary muscle of the dog, exhibit good cell volume regulation when incubated at 37 degrees for 60 minutes in oxygenated Krebs Ringer phosphate solution. The fine structure of the cells is maintained throughout the incubation. This in vitro system was developed in order to test the capacity of myocardial cells irreversibly injured by 60 minutes of ischemia to maintain cell volume. The results showed that irreversibly damaged cells were unable to maintain volume. They swelled markedly, lost Mg2+ and K+ and exhibited structural defects in the plasma membrane of the sarcolemma. These observations establish that loss of cell volume regulation is one of the early events associated with the development of irreversibility in severe myocardial ischemic injury.


Rate-limiting steps of carbohydrate and fatty acid metabolism in ischemic hearts. Control of glycolysis and fatty acid oxidation in ischemic myocardium was studied in isolated working rat hearts. Coronary flow was reduced to the whole heart. In ischemic tissue, oxygen consumption, glycolysis and fatty acid oxidation all decreased in proportion to the restriction in coronary flow. Inhibition of glycolysis developed at the level of glyceraldehyde-3-phosphate dehydrogenase. Restricted flux through this step appeared to result from accumulation of lactate, H+ and NADH. The rate of glycolysis was inversely related to accumulation of lactate. Additions of high levels of lactate to the perfusate inhibited glycolysis in aerobic, anoxic and ischemic hearts. The mechanism of this effect of lactate in anaerobic hearts is unknown, but does not appear to be related to pH changes. Oxidation of fatty acids was restricted at the level of beta-oxidation and high levels of both long-chain acyl CoA and carnitine derivatives accumulated.


Blast crisis as an initial or terminal manifestation of chronic myeloid leukemia. A study of 28 patients. The clinical and morphologic features of nine patients who initially presented with blastic leukemia and the Philadelphia chromosome were studied. Corresponding features were evaluated at the time of diagnosis of blast crisis in 19 patients who had a previous history of chronic myeloid leukemia (CML). Although many of the presenting symptoms and signs were similar, infections, lymphadenopathy, tissue infiltration and central nervous system involvement were more common in patients who presented with blastic leukemia. Marked leukocytosis, basophilia and marrow hypercellularity were present in both groups. Although patients in both groups had morphologic patterns that resembled acute leukemia, cytology suggestive of acute lymphocytic leukemia was more frequent in patients who initially presented with blastic leukemia. Megakaryocyte, platelet and erythroid abnormalities were more frequent in patients with a prior history of CML. Although there were clinical and morphologic features in the patients who presented with blastic leukemia which suggested the diagnosis of CML in blast crisis, chromosome studies were necessary to identify some of these patients. In both groups of patients multiple therapeutic regimens were used. Complete remissions were obtained in two patients; both presented with blastic leukemia, had "lymphoblastic" morphology and were treated with chemotherapeutic agents generally used for the treatment of acute lymphocytic leukemia. It appears that morphology of the blast crisis may be important in choosing the treatment regimen.


Carcinocythemia (carcinoma cell leukemia). An acute leukemia-like picture due to metastatic carcinoma cells. Observation of a unique population of cells on a Wright-stained blood smear of a patient with metastatic breast carcinoma prompted a study to determine their origin. The primary carcinoma contained a marker, the presence of "signet cells." These were demonstrated in direct peripheral smears and buffy coat preparation of peripheral blood and confirmed histochemically by showing positive periodic acid-Schiff, alpha-napthol and beta-glucuronidase reactions. "Carcinocythemia" is suggested as a name for this unusual process observed over a six month period. Studies of the patient's immunocompetence, of circulating cell surface immunoglobulins and karyotype analysis were made. Postmortem examination revealed retroperitoneal fibrosis, splenic atrophy and extensive metastatic carcinoma but no evidence of leukemia. The cells will be contrasted to those seen in a second patient who appeared to have acute myelocytic leukemia complicating extensive cancer involving the bone marrow. The observations suggest that a leukemia-like blood picture due to circulating cancer cells may occur during the course of metastatic breast carcinoma.


A study of the anterior portion of the palate as it relates to orthodontic therapy. 1. The anterior portion of the palate does not appear to move lingually as orthodontic forces move incisor teeth lingually. Although the alveolar bone directly supporting the teeth can be moved distally (and elongated), it does not appear possible to move the apex of the root more distally than the pretreatment position of the palatal plate. Thus, there appears to be an anatomic limitation to the distal movement of maxillary incisor teeth. 2. When incisor teeth are moved distally within the boundaries of the present alveolar process, the supporting bone does not remodel to the roots' new position; when a root which was initially positioned nearer the labial alveolar plate is moved distally against the palatal plate, there was observed no adaptation in the bone to have the root once again located near the labial alveolar plate, the root remained stable against the palatal plate. 3. When great distal movement of incisor teeth results in an alteration in position of the supporting alveolar bone, remodeling of the bone maintains a relatively constant labiolingual width of this alveolar bone. The new position of the tooth and supporting bone appears to be stable. 4. The scanty metallic implant evidence would seem to support histologic observations that alveolar processes are remodeled by apposition of bone on the cortical plate toward which the tooth is moving and resorption of the cortical plate away from which the tooth is moving. 5. There does not appear to be a statistically significant correlation between posterior facial measurements (SNMP) and the labiolingual width of the anterior palate.


The psychedelic model of schizophrenia: the case of N,N-dimethyltryptamine. The authors review the research on N,N-dimethyltryptamine (DMT) as a possible "schizotoxin." DMT produces psychedelic effects when administered to normal subjects, the means are present to synthesize it in man, it has occasionally been found in man, and tolerance to its behavioral effects is incomplete. However, DMT concentrations have not been proven to differ significantly in schizophrenics and normal controls. Also, in vivo synthesis of DMT has not been convincingly demonstrated, and the psychological changes it produces do not closely mimic the symptoms of schizophrenia. The authors conclude that more data are necessary before the validity of this theory can be determined.


New perspectives on orientation and their benefits to clinical orthodontics--part II. As composites were compared from the frontal and lateral, the organization tended to point to orientation of growth of cavities in the face from the divisions of the fifth nerve. Three-dimensional constructed capsules of the orbital, nasal and oral cavities may be reduced to the inputs from the entrance of these nerves into their appointed functional matrices. These orientations were found to be so useful and beneficial that they have been adopted for computer functions. They have also been found fruitful for prediction.


A radiographic study of roots in extraction sites. 1) Roots that are overparalleled to the extent that the apices touch do not relapse to the desired upright positions. 2) Roots that are overparalleled, but the apices do not touch, tend to upright but, in so doing, leave space between the crowns. 3) Roots that are underparalleled at the completion of active treatment tend to maintain their positions or diverge even farther. 4) The best postretention results were cases in which roots and crowns were positioned in normal, upright parallel positions. Slight spaced remaining in these situations appeared to close evenly.


Periodontal status of orthodontically treated impacted maxillary canines. Thirty-four unilateral palatal impacted maxillary canines were brought down by orthodontic means after a radical surgical exposure. The contralateral canines which had erupted unaided served as controls during the study. Measurements of the gingival pocket depths showed that the distal pocket on the treated teeth was significantly deeper than on the control teeth. The treated canines displayed significantly more loss of periodontal support on the buccal and palatal surfaces than did the untreated teeth. Radiographically, there was more alveolar bone loss on the mesial surfaces of the corrected than on the uncorrected canines, the mean distance being 2.06 and 1.51 millimeters, respectively. The age of the patients at the start of treatment did not seem to have any profound influence on the loss of attachment, but the individual variation was considerably greater in adults.


Selection of dentofacial measurements for an orthodontic treatment priority index. A battery of thirty dentofacial measurements was studied in an attempt to identify those measurements most closely related to a clinical assessment of the need for orthodontic treatment in the Dutch population. This was done by inspecting the mean values of these measurements computed within several treatment priority groups, a stepwise regression analysis relating treatment priority scores to these dentofacial measurements, and a quadratic discriminant function analysis between the group of children requiring orthodontic treatment and the group for which treatment was deemed unnecessary. The variables identified by inspection were 1) overjet, 2) overbite, 3) upper molar arch width, 4) the angle defined by articulare-gonion-menton, 5) lower arch length and 6) the ANB angle; the first four of these proved to be the most important when the contributions of all thirty of the variables to the TPI were assessed by means of the stepwise regression analysis. Overjet was also found to be an important predictor variable by Freer in relating Grainger's orthodontic TPI to dentofacial measurements in a group of patients with distoclusion; the ANB angle was found to be the most effective discriminator between normal and Class II American children. The results of the present study then, to this extent at least, agree with those found in other populations. It would appear that any "universal" TPI would have to involve those aspects of dentofacial morphology measured by overjet and the ANB angle. Within the context of the Dutch population the variables identified proved to be effective discriminators in the decision of "to treat or not to treat," correctly classifying 100% of the children in the sample who were judged by two experienced orthodontists as requiring treatment. While this decision rule did suggest treatment for 17% of the children judged to not require treatment, these cases were in the "doubtful" category (Table I) and might therefore warrant continued monitoring before any final decision is reached.


Respirator brain. Report of a survey and review of current concepts. Because of renewed public and scientific interest in the concept of brain death and its diagnostic criteria, an opinion survey was undertaken, polling the membership of the American Association of Neuropathologists, regarding the definition, gross and microscopical features, and pathogenesis of the syndrome popularly designated the "respirator brain." Of the 191 respondents who completed the questionnaire, 174 (91%) indicated that the term respirator brain is properly used to describe a specific pathological entity, and 160 (84%) considered the characteristics of respirator brain to be distinct from those of late fixation. Of the 174 respondents who accepted the designation, 148 (85%) regarded a history of respiratory dependency as essential, and a vast majority (95%) agreed that extensive tissue necrosis occurs with little inflammatory cell reaction; other criteria were more controversial. Microscopical changes that suggest a pathogenetic mechanism attracted a number of informative, limiting, or qualifying remarks. Nonetheless, 54% thought that impaired cerebral blood flow contributed to pathogenesis.


The psychiatrist in the surgical intensive care unit. II. A consideration of staff roles. The stresses present within the Surgical Intensive Care Unit (SICU) affect both patients and staff. The liaison psychiatrist attached to the unit helps in identifying and neutralizing tension displaced from its source. Death, although commonplace on the unit, often engenders strong feelings in the staff. Pulmonary patients, especially those who must be weaned from the respirator, also increase the psychological strain on the staff beyond the necessary effort involved in physical caretaking. Aside from emotional difficulty presented by working with very sick patients, there exists group pressures resulting from hierachy within the staff. Here, particularly, the psychiatrist can promote understanding and reduce polarization.


Survival of dogs subjected to profound hypothermia with circulatory support. Thirty-one anesthetized dogs were surface cooled at 5 C and rewarmed after a variable period. Respiration was controlled with a volume respirator. When cardiac arrest occurred, circulation was provided with the mechanical ventricular assistance (MVA) device in 23 dogs. Of the animals maintained for four hours below 10 C on the MVA, 83% were successfully resuscitated. None of the dogs maintained for two hours below 10 C without circulation could be resuscitated. Eleven dogs were studied for a long-term survival after chest closure. Only four of them survived longer than three days. Death after rewarming was due to severe pulmonary insufficiency. Results of this study suggest that provision of oxygenation and a pulsatile circulation during hypothermia improve tissue viability of nonhibernators. The model shows potential for in situ preservation of multiple organs in the cadaver.


Experience in the use of central venous cannulation. Experience in the placement of central venous cannulae is reported. Sixty patients underwent 67 cannulations, 62 by the supraclavicular approach. The advantages of this approach were speed and reliability of placement and a low incidence of complications. A pneumothorax in an emphysematous man was the only major complication.


Non-familial vitamin D-resistant hypophosphataemic osteomalacia of adult onset: case report. An unusual form of osteomalacic bone disease in a middle-aged woman with a three-year history of widespread bone pain, pathological fractures and loss of height is discribed. Investigations revealed a persistent hypophosphataemia and an increased phosphate excretion index. Urinary glycine excretion was increased. An oral phosphate supplement led to rapid improvement. The features support the diagnosis of non-familial adult onset vitamin D-resistant hypophosphataemic osteomalacia.


Mortality patterns in acute coronary heart disease in New Zealand. An analysis has been made of death certificate information from 4885 persons classified as having died from acute myocardial infarction or other acute or subacute forms of ischaemic heart disease. One-third of non-Maori deaths occur in a public hospital and half the deaths occur at home. One-third of the deaths occur within five minutes, half within one hour, and by 24 hours, two-thirds of all those who die within two months of an acute coronary heart attack, have already died. Sudden death is more common in the elderly and far more common in those who die outside hospital. Post-mortems were performed in approximately a quarter of the patients. In public hospitals, 36 percent of non-Maoris had a post-mortem examination and 10 percent of Maoris.


Public opinion and legal abortion in New Zealand. In 1972 and 1974 opinions on legal abortion were surveyed over national random probability samples each of 2400 respondents aged 15 years and above. Both surveys found majorities favouring certain specific grounds for legal abortion. Some of these reasons approved by the majority are not legal under present law. There is a general consensus in the rank ordering of acceptability of grounds for legal abortion. Polarised minorities of respondents favour absolute legality or illegality of abortion. There has been a swing away from extreme pro- or anti-abortion sentiment to selective support for legal abortion on specific grounds.


The driniking driver: a blueprint for some further action. Statistical information relating to the offence of drunken driving in New Zealand is reviewed. The relationship between alcoholism and this offence is discussed. Two groups of offenders who should be dealt with separately can be identified. A plan is put forward with an outline of methods which could be used for dealing with this problem.


Cytotoxic effects on splenic ultrafiltrates upon leukaemic lymphocytes. Ultrafiltrates from spleen inhibited both DNA synthesis and the proliferation of normal lymphocytes stimulated inculture from both mouse and man without apparent cytotoxicity. However, the same doses of this spleen ultrafiltrate will kill up to two-thirds of the leukaemic lymphoblasts from both mouse and man after 24 h incubation. This unique lymphocytotoxic effect could also be demonstrated on fresh primary cultures of leukaemic lymphocytes and was highly effective on slowly growing established cell lines under crowd culture conditions. Furthermore. ultrafiltrated thymus extract did not affect the DNA synthesis rates of the viability of NC-37 lymphoblasts, which have B cell characteristic. Thymus extract was cytotoxic to Molt cells, which have T cell characteristics.


Characterization of two gangliosides from human leukemic polymorphonuclear leukocytes. Eight bands of gangliosides, from human polymorphonuclear leukocytes were demonstrated by thin-layer chromatography. Bands 4 and 5 were isolated and purified in sufficient amounts to allow their biochemical identification by thin-layer chromatography, gas chromatography and sequential action of glycosidases and neuraminidase. The major ganglioside was characterised as N-acetylneuraminylgalactosyl-beta-N-acetylglucosaminyl-beta-galactosyl-beta-glucosylceramide. A second ganglioside was tentatively identified as N-acetylneuraminyl-galactosyl-beta-N-acetylglucosaminyl-beta-(N-acetylneuraminyl)galactosyl-beta-glucosylceramide. Both gangliosides isolated were hydrolysed by neuraminidase. However, treatment of the intact cells with neuraminidase did not alter the ganglioside pattern.


Discordant patterns of chromosome changes and myeloblast proliferation during the terminal phase of chronic myeloid leukemia. A patient with Ph1 positive chronic myeloid leukemia (CML) developed blastic transformation which by morphologic criteria appeared to be localized to the lymphatic system. Chromosome analysis at this time, however, revealed new chromosomal abnormalities in addition to the existing Ph1 in all tissues studied (lymph node, blood, and bone marrow) consisting primarily of extra chromosome numbers 19 and 9 and a second Ph1. Therapy resulted in clinical remission with significant decrease in the aneuploid cell lines. However, these reappeared with recurrence of the blast crisis. Colony formation in semisolid culture of blood and marrow cells at the time of initial blast crisis yielded growth patterns characteristic of CML. On recurrence of the blast crisis after therapy, growth patterns were characteristic of CML in blast crisis or acute myeloblastic leukemia even though blood and marrow still showed relatively low levels of myeloblasts and promyelocytes. Possible explanations are discussed for the disparity in distribution between morphologic and chromosomal abnormalities in this patient.


Cryoprotective agents as inducers of erythroleukemic cell differentiation in vitro. The ability of families of compounds with known and potential cryoprotective properties to induce the differentiation of Friend leukemia cells in vitro was studied. For each agent, both the proportion of differentiated cells in the culture and the total amount of heme/10(7) cells were determined. Within each family of compounds there was a direct correlation between a compound's cryoprotective ability, its ability to donate electron pairs for hydrogen bonding (basicity), and its ability to induce differentiation. While individual agents differed with respect to the proportion of cells which were induced to differentiate, the biology of the process of differentiation appeared to be similar, regardless of the agent used. A cell line which was unresponsive to DMSO was responsive to other inducers, suggesting that this DMSO-resistant cell line differed from its parent DMSO-responsive cell line either in its metabolism of the inducers or in the ability of the inducers to enter the cell. Alternatively, there may be more than one mechanism involved in the chemical induction of differentiation.


Clinical study of rubidazone (22 050 R.P.), a new daunorubicin-derived compound, in 170 patients with acute leukemias and other malignancies. Rubidazone was used as sole chemotherapy in 170 adults and children with acute leukemia and sarcoma. When rubidazone was employed to treat the first attack, complete remission was achieved in : 1) 40 out of 70 patients (57%) with AML; 2) two out of six patients with AML where previous chemotherapy had failed; 3) four out of five patients with ALL; 4) 12 out of 14 patients with acute monoblastic leukemia. When used to treat relapse, rubidazone produced complete remission in : 1) 14 out of 31 cases of AML; 2) 18 out of 39 cases of ALL; 3) 2 out of 3 cases of non-Hodgkin lymphoma. Treatment of a case of rhabdomyosarcoma was unsuccessful. In the treatment of acute myeloblastic and monoblastic leukemias, it may be concluded that rubidazone induces a higher rate of complete remission than any other previously reported drug which was used alone. It also achieves remission rates similar to those resulting from a combination of daunorubicin and Ara-C. Furthermore, when compared with daunorubicin, rubidazone allows better control of the induction of aplasia.


Specific antigen stimulated lymphocyte proliferation in osteosarcoma. A lymphocyte proliferation assay (LPA) for cellular immune responses to osteosarcoma antigens is described and applied to an examination of peripheral blood lymphocytes (PBL) taken from osteosarcoma patients. The antigen preparations were derived from 3 M KC1 solubilized osteosarcoma, taken from a limited number of patients. Lymphocytes from most tumor-bearing patients were stimulated to significant proliferation when cultured in normal human serum. Such stimulation was observed whether or not the lymphoid cells were preincubated 24 hours at 37 degrees C prior to addition of antigen. Patients whose lesion had been resected and who were without evidence of disease for 5-70 months had diminished proliferative responses. Lymphocytes from normal subjects, from patients having other types of sarcoma, and patients having carcinomas rarely responded to the soluble osteosarcoma antigens. When responsive PBL taken from tumor-bearing patients were cultured in autologous serum, the proliferative responses were abrogated or blocked. Serial assays made in the course of bearing this tumor under a variety of therapeutic regimens, including an immunotherapy protocol, suggest that the LPA may be useful in monitoring clinical progress of the disease and possibly in other immunotherapy protocols for osteosarcoma.


Chromosomes and causation of human cancer and leukemia. XIII. An evaluation of karyotypic findings in erythroleukemia. This study was an attempt at defining the cytogenetic features of erythroleukemia (EL), particularly as related to the group of AML patients with MAKA (major karyotypic abnormalities), which generally were caused by three or more cellular events of translocation or nondisjunction. Eight of the 17 patients with MAKA had a diagnosis of EL or possible EL. In most cases, MAKA was featured by hypodiploidy, karyotypic instability, and polyploidy in the leukemic cells. The most common abnormalities were loss of B or G group chromosomes and gain of a  no. 16 or one or more marker chromosomes. Each of the markers of 2q+, Dq+, mar(A2, st), mar(C12, M), r(?F) and minute metacentric and acentric markers was observed in two or more patients. The extent of polyploidy seemed to be correlated with the proportion of erythroid precursor cells in the marrow and with the karyotypic instability. Since the patients exhibited the same chromosomal features, whether or not they had a diagnosis of EL or possible EL, and since patients without such a diagnosis also had cytologic suggestions of EL, a close relation of MAKA to EL is assumed. It is believed that patients with MAKA constitute one of the three chromosomally classifiable groups of EL.


Leukemic mitochondria. II. Acute monoblastic leukemia. Qualitative and quantitative ultrastructural studies were performed on mitochondria of leukemic monoblasts from 15 patients with acute monoblastic leukemia. Similar comparative observations were made on mitochondria of myeloblasts from 14 hematologically normal controls. No significant quantitative differences were noted between normal and leukemic mitochondria. Area measurements were approximately equal. Qualitative differences between the two groups consisted of increased numbers of irregularly shaped mitochondria, damaged mitochondrial membranes, mitochondria with damaged matrix, and small granules in mitochondria in the leukemic group. Leukemic cells exhibited nuclear-mitochondrial contact and virus-like particles within damaged mitochondria. To confirm the presence of virus-like particles and to aid in our understanding of nuclear-mitochondrial interaction, a C-type virus producer MSV-MLV infected rat embryo cell culture was used for additional analysis. Mitochondrial abnormalities and increased frequency of virus in damaged mitochondria, often attached to mitochondrial membranes, were noted. Several lysosomes exhibited accumulations of virus and budding into lysosomes from lysosomal membranes. Mitochondria are important organelles in glycolytic-oxidative phosphorylation pathways, and carry extranuclear genetic information. Further studies of morphologic and biochemical abnormalities of leukemic mitochondria and the interaction between the mitochondria and the nuclei in leukemic cells are needed to provide researchers with data on extranuclear factors operating in oncogenesis.


Chronic neurologic disturbance in childhood leukemia. Twenty-three leukemic children were studied prospectively to detect chronic effects of therapy. All patients received CNS prophylaxis, including 2400 R cranial irradiation, and intermittent maintenance therapy with intravenous methotrexate, cyclophosphamide and cytosine arabinoside. Neurologic symptoms were observed in 12 patients, all of whom had intermittent limping and mild incoordination, between the 10th and 18th month of maintenance therapy. Five of the 12 sustained seizures and four of these had subsequent abnormalities in motor, perceptual, behavioral or language development. Three school-aged children have learning disability and perceptual-motor defects. Studies of CSF folate and MTX content are presented but not helpful in delineating the etiology of these neurologic symptoms.


Acute and chronic effects of methotrexate on hepatic, pulmonary, and skeletal systems. With the progressive improvement in the survival of children with acute lymphocytic leukemia, the question of late effects of therapy on normal tissue becomes a more significant problem. In a review of a large number of children who have received long-term treatment with chemotherapy, especially methotrexate, a significant increase in the serious effects on hepatic, pulmonary, and skeletal tissue was noted. A review of the methotrexate-induced acute and chronic changes seen in these tissues is the basis for this report.


In vitro colony formation of transplantable rat leukemias in comparison with human acute myeloid leukemia. In vitro colony formation in two different soft agar systems was studied with bone marrow from untreated patients suffering from acute myeloid leukemia (AML) and from rats in various stages of two different transplantable myeloid leukemias. In both the thin-agar-layer system, which uses a feeder layer of fetal fibroblasts, and the Robinson culture system, human AML marrow failed to produce colonies. A similar failure was observed with the BN rat leukemia. In contrast, the Shay rat leukemic marrow produced an abnormally large number of colonies in the later stages of the disease. Evidence was obtained that the colonies produced by the Shay leukemic marrow consisted of leukemic cells, and that the disappearance of colonies from human AML and from BN rat leukemic marrow is caused by the numerical disappearance of normal pluripotent hemopoietic stem cells from the marrow and by the inability of the clonogenic leukemic cells to produce colonies in vitro. The results indicate that the BN rat leukemia is a realistic animal model for human AML.


Drug-induced stimulation of transport of hydrolyzed nitrogen mustard and choline by normal and leukemic human cells in vitro. The effect of morphine and cocaine on the transport of hydrolyzed nitrogen mustard (NH2-OH) and choline by peripheral blood cells of normal subjects and patients with chronic lymphocytic leukemia, acute lymphoblastic leukemia, and acute myeloblastic leukemia was determined. Transport of HN2-OH by lymphocytes from normal individuals and patients with chronic lymphocytic leukemia was stimulated by morphine and cocaine and, in each case, the effect was statistically significant (P less than 0.05 or greater). However, choline transport by normal lymphocytes was not altered by cocaine and was only slightly stimulated by morphine; choline transport by lymphocytes from patients with chronic lymphocytic leukemia was not stimulated by either morphine or cocaine. HN2-OH and choline transport by cells from patients with either acute lymphoblastic or myeloblastic leukemia was stimulated to a comparable degree by both drugs. Stimulation of HN2-OH transport by morphine and cocaine was greater in normal lymphocytes than in acute leukemic cells and the differences were highly significant (p less than 0.001). Conversely, stimulation of choline transport was more marked in acute leukemic cells than in normal lymphocytes, and these differences were also highly significant (p less than 0.001). It was previously shown that transport of nitrogen mustard by normal and leukemic human cells was biphasic in nature, consisting of a choline-independent component at "high" drug concentrations and a choline-dependent system at "low" substrate concentrations. The preferential stimulation of the low-dose, choline-dependent system by morphine and cocaine in acute leukemic cells relative to that observed in normal lymphocytes suggests a possible mechanism of increasing the therapeutic index of nitrogen mustard.


A longitudinal study of morphological craniofacial patterns via P-A x-ray headfilms in cleft patients from birth to six years of age. 652 P-A X-ray headfilms of 51 unilateral cleft lip and palat, UCLP; 27 bilateral cleft lip and palate, BCLP; and 62 isolated cleft palate, CP were studied longitudinally at 0-3 months, 4-6 months, and annually from 1:0-6:0 years. Breadth change, height change, and growth direction of nine paired landmarks were investigated by means of the rectangular coordinate system with right to left zygomatico-frontal suture (Zf) point line as the X-axis and the perpendicular line to this X-axis at the mid-point between the right and left Zf points as the X-axis. Major findings were: (1) Study of Sphenoid body, interorbital, bizygomatico-frontal suture, and bizygomatic arch breadths showed that BCLP had a significantly broader face  than either UCLP or CP. An apparent tendency to hypertelorism still remained at 6:0 in this group while UCLP and CP groups were both close to the Bolton Standards. (2) Nasal and maxillary bredths of BCLP and UCLP were significantly wider  during the first year than in CP, but they showed only a slight growth change after the age of one year, compared to constant growth in CP. (3) All marked structural differences disappeared by 6:0 suggesting the effects of lip and/or palate surgery. (4) A slight cross-bite was found in UCLP and BCLP, but there was no such cross-bite in CP. (5) The effect of clefting was seen in mandibular dimensions where the bigonial notch was slightly broader than in non-cleft averages. (6) Upper facial height occlusal height, and posterior total facial height in each cleft group seemed to be larger than the Standard, though both maxillary height and gonial notch height approximated the Standard by 6:0 (7) From 0:3-6:0, there was no noteworthy difference among the cleft groups in either growth direction or facial symmetry of upper face and mandible. It was only in the mid-facial and dental areas that notable characteristics peculiar to the type of cleft were found. The landmarks of nasal aperture, maxilla, and dental arch showed a slight medial displacement on the affected side, although the degree and amount depended on the cleft-type.


Issues involved in the evaluation of velopharyngeal closure. The development and use of frontal and base-view fluorography have increased the value of cinefluorography in the evaluation of velopharyngeal closure. This paper discusses problems in the fluorographic examination of the closure mechanism, the need for other measures of velopharyngeal closure, and the validation of closure measures. Reliability data are needed for measurements made from frontal and base-view films and tapes. Measures in addition to those of a fluorographic nature are needed for the identification of persons with questionable velopharyngeal closure and for use in the evaluation of training procedures that may contribute to improved use of the velopharyngeal closure mechanism. A pattern of relationships among fluorographic and nonfluorograph measures of velopharyngeal closure can be studied in the validation of both classes of measures.


Ultrasonic measurement of lateral pharyngeal wall movement at the velopharyngeal port. Pulsed ultrasound was used to assess lateral pharyngeal wall (LPW) movement at the level of the velopharyngeal port in three adult males and two adult females. All subjects were normal talkers, and data were collected while each produced all combinations of the vowels /a/ and /i/ and consonants /p, t, k, s, m, n/ in a VCVCV context. On a qualitative basis, it appears that ultrasound technology has potential application for the measurement of LPW movement. However, a number of problems must be resolved before ultrasonic techniques surpass current methods of studying velopharyngeal function and/or incompetence.


The mathematics of cleft lip and palate treatment evaluation: measuring the desirability of treatment outcomes. A study was undertaken to investigate the applicability of utility theory to cleft lip and palate treatment decision making. Questionnaires were used to assess value judgements and attitudes toward risk from 119 individuals associated with seventeen cleft lip and palate treatment centers. Significant differences were found to exist between the values expressed by clinicians grouped according to their specialty or the facility to which they were affiliated. Fathers of cleft lip and palate children differed from cleft palate teams in their judgements regarding the relative values of speech and cosmetic treatment outcomes. No such differences were found between team members and mothers, however. It is suggested that these differences affect the desirability of treatment decisions and the outcomes that follow from them. Therefore, cleft lip and palate treatment planning and the evaluation of alternative therapeutic interventions might be based on a mathematical theory of decision making that explicitly incorporates the subjective assessment of a child's habilitative needs and the goals of the habilitative process.


Social response to acoustic and visual characteristics of oral cleft. This study was concerned with societal preference among speech, visual, and speech-visual characteristics of persons with repaired cleft lip and palate. A 16 mm motion film with sound was professionally made of 17 male, adult, cleft lip and palate speakers reading the first paragraph from "The Rainbow Passage." A heterogeneous group of 30 adults rated their preference for each of the conditions-auditory, visual and auditory-visual-on a seven-point equal-appearing intervals scale. A four-factor design analysis of variance with repeated measures was performed to determine whether the thirty judges preferred at least one variable of the three variables tested. Results indicated that this heterogenous population had no preference among auditory, visual, or auditory-visual characteristics of adult males with repaired cleft lip and palate. These variables appear to be considered of equal importance by persons who are representative of the lay public.


A cineradiographic investigation of velar movement variables in two normals. The purpose of this investigation was to study certain aspects of velar dynamics among normals. Two adult subjects, one male and one female, were filmed using high-speed (100 fps) lateral-view cineradiography. Small radiopaque cups were attached to the surface of the soft palate and other articulators for tracking purposes. Trajectories of the velar fleshpoint in the midsagittal plane were demonstrated. Measures of velar velocity, velar displacement, and duration of transitional movements were studied in relation to the effects of phonetic context and speaking rate variation and were compared to the activity of other articulators. Velar positioning also was studied during nasal consonant production in relation to the effects of vowel context.


An evaluation of proposed revisions to the W.H.O. manual "Oral Health Surveys-Basic Methods". The authors describe the organization and results of an epidemiologic training program which formed part of a W.H.O. sponsored course in public health dentistry held in Malaysia in May-June 1975. Twenty-two participants from 16 countries took part. They had a wide variety of qualifications and training; only four had had previous experience in the conduct of an oral health survey. The method and criteria that were proposed for inclusion in the second edition of Oral Health Surveys - Basic Methods were tested in two calibration exercises and one field trial. The usefulness of most of the recommendations was confirmed. The main problem areas concern dentofacial anomalies, intense gingivitis and advanced periodontal involvement. A successful feature of the study was the practicability for public health planning of assessing requirements for treatment.


Caries experience as predictor for caries incidence. The caries increment (filled surfaces) from the ages 7 to 15 years were compared in children with three or fewer (low prevalence group) or eight or more filled surfaces (high prevalence group) at the age of 8. The children participated in a fortnightly fluoride mouthrinsing program (10 ml of 0.2% NaF). Following 8 years of dental treatment and caries prophylaxis, the caries increments were 11.4 (s.d. = 7.7, n = 23 subjects) and 17.1 (s.d. = 9.6, n = 39 subjects) surfaces, i.e. significantly different (t = 2.376). Significantly (t = 4.034) more fillings had been required in the high than in the low prevalence group (31.1 +/- 17.1 vs. 15.5 +/- 9.6). The "risk group" could be identified at the ages of 7 to 8 by high caries prevalence and high ratio fillings/caries increment. Social class and number of teeth accounted more for the initial caries prevalence than for the caries increment. Correlation analyses revealed a significant, but not strong (r = 0.50), association between caries prevalence at the age of 7 and increment of fillings.


A regression model analysis of longitudinal dental caries data. Longitudinal data on caries experience were derived from the reexamination and interview of a cohort of 306 subjects with an average follow-up period of 33 years after the baseline examination. Analysis of the data was accomplished by the use of contingency tables utilizing enumeration statistics compared with a multiple regression analysis. The analyses indicated a strong association of caries experience at one point in time with the caries experience of that same person earlier in life. The regression model approach offers adjustment of any given independent variable for the effect of all other independent variables, providing a powerful means of bias reduction. The model is also useful in separating out the specific effect of an independent variable over and above the contribution of other variables. The model used explained 35% of the variability in the DMFS scores recorded. Similar models could be useful adjuncts in the analyses of dental epidemiologic data.


Rapid diaphyseal destruction. An unusual osseous manifestation of chronic granulocytic leukemia. A patient with chronic granulocytic leukemia developed an unusual rapidly progressive mid-diaphyseal femoral lesion. Differentiating this myeloblastic lesion from other round cell tumors is most reliably done by a Wright-Giemsa stained touch preparation. Prompt palliative therapy with long bone stabilization permitted the patient to remain ambulatory until shortly before his death.


Prevalence of oral soft and hard tissue lesions related to mechanical toothcleansing procedures. The prevalence of oral soft and hard tissue lesions related to mechanical oral hygiene procedures was recorded and correlated to toothbrushing habits and oral hygiene status in two selected samples. Fifty-one percent of 533 persons examined exhibited gingival retractions and 45% had wedge-shaped defects in the cervical area of one or several teeth. Both types of lesions were often seen in the same area, indicating a common etiologic factor. The subjects with a good oral hygiene status, as well as those who brushed more than twice daily, showed a high frequency of lesions. The various toothbrushing techniques did not, however, seem to influence the development of such lesions in the present material. Subjective symptoms were reported in a few cases only.


[Results of conservative and surgical treatment of jaw fractures]. In the majority of the patients with fractures of the jaws treated in the period covered by this study, conservative therapy has shown satisfying results. In intraoral splinting, periodontal lesions could largely be avoided by adequate oral hygiene. Surgery must still be applied in those cases where conservative methods failed to be successful.


[Transoral osteosynthesis in mandibular fractures]. The extraoral approach is frequently used for repositioning and stabilizing fractures of the mandible in which osteosynthesis is indicated, but also the transoral approach may be applied. Depending on the location of the fracture, the technical difficulties vary in operations using the oral access. By means of suitable instruments and appropriate operating techniques, which are described for the various fracture types of the lower jaw, almost all fractures of the mandible can be operated upon using the oral approach. The essential advantages of such a procedure are that the facial nerve cannot be damaged and an esthetically unfavourable external scar is avoided.


[Viewpoints on primary and secondary treatment in orbital fractures]. The orbit is frequently involved in fractures of the middle part of the face. In order to maintain optimum functioning of the eyeball after healing of the fracture, anatomically correct reconstructioning is indicated as early as in primary treatment. In those cases where this is not possible, a secondary treatment is required which should be carried out in cooperation with the ophthalmologist.


[Comparative experimental measurement of the stimulus threshold of the effect of the local anesthetic Ultracaine (Carticaine)]. For objectifying clinical experience, we measured and compared experimental stimulus thresholds with Ultracain 4% and Xylocain 2% in the upper and lower jaws in double blind tests. By means of electronically controlled rectangular impulses the latent period, depth and duration of anesthesia were registered. Relevant differences were found for plexus anesthesia in the lower jaw. The Ultracain preparation is characterized by a high capacity of bone penetration.


[Electrical measuring of the effect of local anesthesia]. Of all methods for testing local anesthetic effects, only threshold determination with electric impulse stimulation of the dental pulp has proven reliable. Alternating current impulses are the most suitable.


[Studies of the effectiveness of impersonal teaching by means of a sound film: "Conduction anesthesia on the mandible"]. The thesis that students could be instructed by audio-visual aids alone equally as well as by a personal instructor was tested by experiment. A teaching program, i.e. a sound film, was made and was shown to first-year clinical dental students. At the same time the usual lecture was offered to these students. Subsequently the knowledge acquired was examined. The results support the initial thesis, but at the same time it must be concluded that the highly differentiated psychomotor teaching objectives of dentistry cannot be achieved without individual instruction.


[Is hygiene endangered in the modern dental office?]. Hygienic studies of the manual buttons of a modern dental unit show that these buttons are being contaminated during treatment. The number of germs depends on the duration of treatment and on the number of patients treated. As these buttons were pushed with the foot in dental chairs of older design, the ergonomic advantages of modern dental units do not mean hygienic advantages to the same extent.


[Total bacterial count and the occurrence of Streptococcus mutans and Streptococcus sanguis in the air of various work areas]. In the various rooms of the Würzburg Dental School, the total germ contamination of the air and the incidence of S. mutans and S. sanguis strains was studied. The total number of organisms found as well as the number of the two polysaccharide-producing organisms varied considerably. The presence of the two streptococcal strains is not restricted to the air in dental surgeries. It is considered to be an additional risk that by far the highest incidence of the cariogenic S. mutans strain is found in the air of the rooms of the outpatient clinic for restorative dentistry and periodontology.


[Cytological studies of the gingiva in endonseous extension implantations]. In addition to radiographs and clinical diagnostic-methods, exfoliative cytology can be used as a testing method for the evaluation of implants. The simple and gentle method of sample taking permits regular follow-ups. While in the area of stable grafts a normal cytogram is obtained, the cytogram of the area of loose grafts shows all the signs of inflammation on the cellular level: "a shift to the left", low indices of keratinization and eosinophilia, cellular alterations, presence of bacteria, leukocytes, and lymphocytes.


[Clinical aspects and pathology of tumors of the temporomandibular joint]. Two primary tumors of the temporo-mandibular joint are presented. Because of their unspecific clinical symptoms, the diagnosis could be confirmed by surgical intervention and histopathology only after a long period of observation. Benign temporo-mandibular joint tumors can still be managed, while in malignant tumors the further course of the disease is characterized by a poor prognosis.


[Catamnestic surveys in 371 cases of abscess of the maxillofacial region in childhood]. Catamnestic surveys of 371 children who suffered from abscesses during the past ten years (1965 to 1974) showed that type and location of the abscesses and their incidence in the various age groups are typical and differ from those of abscesses in adults. These results are discussed and compared with the data found in the literature.


[Fluoride levels in plasma and femur after single and multiple administration of fluoride in the rat]. In 12- and 22-week old rats the fluoride levels in plasma and in the femur were studied over a period of 24 hours. Without fluoride administration, the normal fluoride concentration was 0.01 to 0.03 ppm in plasma and an average 50 ppm in the femur. Peak values were observed in the plasma 20 to 40 minutes after fluoride intake, with the peak levels being the same irrespective of the age of the animals and the duration of fluoride administration. A quick and obvious fluoride retention in the femur was registered in young animals. Fluoride elimination from the plasma is influenced by the age of the animals and the previous fluoride load.


[The lead and cadmium content of dental calculus in various occupational groups]. Atom absorption spectrum analysis was used for determining the lead and cadmium contents in calculus. Because of the small amounts present it was not possible to distinguish between sub- and supragingival calculus. Differences in environment and working place result in significant differences in the absorption of lead and cadmium. The lead values were especially high in workers of the chemical and automobile industries, while the cadmium values were high with traffic policemen and workers of the chemical industries.


[Inhibition effects of extracellular glucosyltransferase from Streptococcus mutans]. The extracellular, gel-electrophoretically pure glucosyl transferase (GT) of Streptococcus mutans st.227 was incubated with various inhibitors and the synthetic product quantitatively determined. The GT activity was increased with low urea concentration (0.3 - 1.2 M) and inhibited with higher urea molarity. Sodium dodecyl sulfate and quarternary ammonium compounds (detergents) have a clear inhibiting effect starting with 0.005%, while NaF, KSCN, ethylene diamine tetra-acetic acid and sugar alcohols do not have any influence.


[Physical factors in tissue injuries of the masticatory organ]. For the analysis of tissue trauma physical quantities and mechanisms were registered by means of electronic measuring devices in the model example of jaw fractures. Samples of pig jaws were subjected to load until breaking by a pendulum hammer: by impulse loading of the teeth and the jaw bone itself. Using oscillograms of the deformations of the teeth and jaws and force, the most important biophysical quantities of this trauma are explained: impact speed, impulse, force, tissue deformation, increase of force.


[Transsinusal repositioning and retention of zygomatic fractures]. In the treatment of impression fractures of the zygoma transsinusal repositioning of the fragments and their retention by means of a simple inflatable balloon catheter has proved successful. This method not only permits retention and drainage of the maxillary sinus but also postoperative correction of visual disturbances, if necessary.


[Mini-plate osteosynthesis on the zygoma]. A method is described in which the principles of plate oseosynthesis at the zygoma are applied in the region of the zygomatico-frontal suture. A mini-plate in line with the spheric gliding principle of Arbeitsgemeinschaft für Osteosynthese is applied at the zygomatico-frontal suture after repositioning by means of a hook. The miniature plate enables screwing of the fragments and stabilization of the zygoma with regard to the possible direction of dislocation.


[Conditions for the performance of periodontal surgery]. Periodontal surgery is an integral part of systematic periodontal therapy, is performed only after establishment of good hygienic conditions in the mouth, does not aim at maintaining single teeth that would have to be extracted and is indicated only if the patient is performing adequate personal oral hygiene.


[Methods for mucogingival surgery and its results in gingival recession]. Muco-periosteal pedicle flaps, free mucosal transplants as well as a combination of these two methods may be used for treating gingival recessions. The method selected and the therapeutical success depend on whether or not the interdental gingiva is also affected. From this viewpoint, three different types of recessions can be distinguished. Type I recessions with intact interdental gingiva on both sides can successfully be treated by all methods. In type II recessions with partial loss of the interdental gingiva on one side, free transplants as well as their combination with sliding flaps show the best results. Recessions at two adjacent teeth with loss of the interdental gingiva (type III) can only be treated with free mucosal transplants. Prognosis of successful treatment diminished from type I to type III.


[Report of a case of idiopathic gingival hyperplasia]. The clinical and histological picture of a rare gingival disease, i.e. idiopathic gingival hyperplasia, is discussed in detail on the basis of a case of our own Comprehensive diagnostic measures were taken to exclude other possible causes of a hyperplasia of the gingiva. Despite a rapid recurrence after gingivectomy, a "wait and see" attitude is assumed and the next therapeutical procedure is planned only after completion of puberty.


[Free mucosal transplantation in accidental periodontal lesions]. In order to eliminate mucogingival adhesions after lesions of the vestibulum caused by an accident, they must be freed and the scars must be excized. To create and restore a sufficiently broad gingiva propria and to deepen the vestibulum, the new wound area should be covered by a graft which at the same time counteracts resorption of the alveolar bone. A free graft from the palatal mucosa is suitable. It ideally replaces the alveolar mucosa, since it is the same type of mucosa as the attached gingiva, i.e. compact fibrous keratinized mucosa, and leads to bone apposition by activating the osteoblasts. Clinical experience and histological examinations show that this transplant permanently keeps its characteristics and undergoes secondary shrinking to a small extent only.


[Local periodontal findings following interalveolar and perialveolar maxillary osteotomies]. Follow-ups in 30 patients with osteotomies of the upper jaws showed that the risk of periodontal damage is small in primarily healthy periodontia. In most of the cases, the periodontal pockets in the region of osteotomy were less deep than those in other regions of the maxilla.


[Periodontal reaction to interdental osteotomy]. Interdental osteotomy presents a small risk for the tooth adjacent to the line of the osteotomy. Five out of 41 teeth adjacent to the site of an osteotomy showed loosening degree 1. The PM index rose from 1.0 to 1.4. The depth of the periodontal pockets did not change. The roots of two out of 41 teeth were damaged during osteotomy, but not devitalized.


[Studies on oral hygiene and periodontal prophylaxis in patients with jaw fractures]. Oral hygiene experiments with H2O2 and chlorhexidine rinsing were performed in 15 patients with dental splints for jaw fractures and intermaxillary wiring. To measure the various cleaning measures, Löe's plaque index (1967) was determined at the 7th, 21st, and 35th postoperative days. The 2% chlorhexidine gluconate was always by far superior to H2O2 as far as plaque inhibition was concerned. With chlorhexidine plaque reduction up to 69% and H202 reductions up to 22% were observed. After a test period of about 5 weeks, only slight side-effects were recorded, such as discolorations at the lingual side of the teeth and in few cases bad taste or dark coating of the tongue.


[Periodontal conditions after surgery of maxillary sinus fistulas]. In 38 patients the periodontal conditions after closure of antrum perforations are examined. The following indices are used: plaque index, gingival index, degree of loosening, depth of pocket and index of osteolysis. As compared to the opposite side, significant atrophy of the bone is found in the region of the perforation. Otherwise no significant differences between the operated side and the non-operated side are observed.


[Periodontal conditions of the teeth next to the fracture line after stable plate osteosynthesis in the mandible]. Follow-ups in 21 patients with 30 fractures of the lower jaw which were treated with stable plate osteosynthesis showed that 94% of the teeth adjacent to the fracture line were not extracted. The rate of secondary healing was 7%. Evaluation of the periodontal conditions showed that only 14% of the teeth were not worth keeping and 45% of the teeth required treatment. It is pointed out that when treating mandibular fractures with stable plate osteosynthesis, retention of the teeth in the fracture line does not mean an increased risk as far as secondary healing and the tooth itself are concerned.


[Clinical, radiologic and histomorphological aspects of the hemangiopericytoma head and neck region]. Three hemangiopericytomas of the head and neck region with different clinical development are presented. In one patient the tumor was benign, in the two others malignant. In contrast to the opinion prevailing in the literature, histological criteria were found by means of which the degree of malignancy of these three tumors could be established. Irrespective of the degree of malignancy, radical surgery is recommended as therapy. Postoperative radiotherapy follows in those cases where a safety margin of clinically non-involved tissue surrounding the tumor could not be removed.


[Closing an anterior sinusal opening using lyophilized dura]. The systematic application of lyophilized dura for closing the anterior opening of the maxillary sinus after primary and revisional surgery at the maxillary antrum is reported. This method was applied in 32 primary maxillary sinus operations and in 6 revisional operations. The follow-ups showed a satisfactorily small number of postoperative complaints. This allows the conclusion that lyophilized dura is a suitable material for closing the anterior window in operations on the maxillary sinus.


[Computerized statistical documentation of mandibular fractures]. The advantages of a form for case history, clinical findings and therapeutical measures which meets the requirements of computerized documentation, are pointed out by means of individual groups of questions. In this connection, an example from maxillofacial traumatology, i.e. fractures of the mandible, is discussed. After discussion of the questionnaire, some results of the evaluation of the compiled data are presented.


[Possibilities and limitations in the conservation of traumatized deciduous teeth]. A survey is given on the various traumatic lesions of deciduous teeth and the therapeutical measures. The latter aim at retaining every traumatized tooth, if possible, in order not to disturb the growth of the jaws. A study by the authors on 116 recently traumatized deciduous teeth showed that almost half of the teeth could be retained.


Pins and posts--why, when and how.

Pins and posts--why, when and how. Pins and posts retain restorations and protect remaining tooth structure; they are indispensable to conservative operative dentistry. Effective utilization of these pin-post systems requires application of proper biomechanical principles for each clinical situation. No one design will suffice in every case. A parallel, serrated, cemented device in a precise matched channel is the ideal combination of characteristics. When tooth morphology or heavy function require increased retention, it may be achieved by increasing pin-post length, diameter, and number or by utilizing the resilience of dentin. However, the dentist must be aware that the price for more retention is the increasing risk of damaged tooth structure. Optimal long range results will be obtained by utilizing pins and posts in conjunction with veneer types of restorations. When used in this manner, they will save many teeth each year and simultaneously reduce the rate of failures.


Rationale for designing cavity preparations in light of current knowledge and technology. No restorative material presently available is as good as supported tooth structure and it is unlikely that a usable dental restorative material with the physical properties of enamel will ever be developed. The purpose of cavity preparation is to remove carious material and preserve sound tooth structure. Any additional removal of tooth structure is necessary for the convenience of the operator or because of limitations of the restorative materials. Presently available esthetic restorative systems for nonfunctional areas and selected anterior functional areas allow for designing cavity preparations where the only two considerations are removal of caries (and unsupported enamel) and placement of retentive features. The problem of cavity design for restoration of functional surfaces is not answered easily, but there is reasonable hope that in the near future an esthetic restorative material will be available that has the strength and other necessary properties to serve in functional areas. There should be no specific "ideal" design for cavity preparation. Each defect should be custom designed to remove the caries or defect and perform the additional steps necessitated by the limitations of the operator or restorative material. As advocated by Black in one of his later publications, it is necessary to make mouth-by-mouth and tooth-by-tooth judgements concerning the most desirable outline form to be obtained.


Conservative preparations for cast restorations. Partial veneer crowns still play a role in modern restorative dentistry. They must be used in the right situation with thoughtful treatment planning, and they must be done well in accordance with certain principles. Three-quarter crowns are less retentive than full crowns, but they can be used successfully as single unit restorations and retainers for short span bridges. Retention can be enhanced by the use of proximal boxes. The M.O.D. onlay, a modified inlay with occlusal coverage, minimizes the damaging effects of stress generated by occlusal forces. There is little indication for the use of M.O.D. inlays or large two surface inlays.


Diagnosis and treatment of pulpal distress. Both diagnosis and treatment of vital pulp tissues encompass some fairly comprehensive varieties of methods and materials. Diagnosis is arrived at in terms of probability. No one can be absolutely sure that the diagnosed degree of pulpal distress is in fact the actual state of affairs. Treatment, therefore, must be best be a probability also. There can be no guarantee that the treatment rendered will succeed in every instance. Any diagnosis and treatment of reversible pulpal distress is a gamble on the part of both practitioner and patient. However, utilization of every diagnostic means at his disposal, knowledge of the many treatment modalities available for use, and the ability to correlate both the diagnosis and treatment phases of a given case will result in a high probability of success. This is indeed rewarding to both the patient and the dentist.


The most conservative and longest lasting restorative service. At this time in the evolution of dentistry no single technique allows the conservative and long lasting service which compacted gold restorations will provide. This article has shown the various types of these restorations undertaken in busy, financially successful practices and has supported the routine use of this therapy by more practitioners. Various supplies, equipment, and devices have been suggested.


Conservative approach to the placement of retentive pins. A thorough understanding of the basic principles of cavity preparation and knowledge of tooth morphology are necessary for the successful positioning of pin channels in the tooth. Sufficient dentin surrounding the channel is necessary for adequate strength, to avoid external fractures of tooth structure and to protect the pulp. Once the channel location is decided upon, it should be made parallel with the external surface of the tooth rather than its long axis. It is suggested that the operator use only one pin per missing cusp of the tooth and that where possible this pin be placed in the area of the line angles. Optimal length of the pin into the restorative material is 2 mm and in the dentin is 2 to 3 mm for those retained by dentinal elasticity and 3 to 4 mm for those retained by cement. The use of a rubber dam for isolation procedures is encouraged, as well as radiographs and diagnostic casts to aid in the successful placement of retentive pins.


Continuing education.

Continuing education. The greatest fault in current dental education is that for many dentists education ceases with graduation. It should instead be a lifetime process beginning with the undergraduate course and progressing through clinical experience alternating with continuing education. The ultimate objective should be good oral health for the population but in many cases the service provided falls short of the ideal taught at dental school. Education alone will not solve this problem. Other factors such as job satisfaction, pay and superannuation, general policy and the organization of the individual surgery play a part. Planning of continuing education should start with a comparative analysis of dental care as it is and as one would like it to be. At the undergraduate level the concentration must be on theoretical knowledge and the practice of clinical skills. Growing clinical experience will develop these skills and will also give rise to new feelings about work, patients and the world around. Continuing education must update the dentist's theoretical knowledge which is then advanced at collective sessions. Although voluntary, more than 20 per cent of all private dentists in Sweden are currently taking part in this programme.


Open meeting of the Commission on Dental Education. 'What went wrong with my dental education?' A look back at the undergraduate course. In this paper, my own undergraduate course from 1961 to 1966 at Guy's Hospital, London, is described and the merits and shortcomings of this course discussed. Subsequent alterations and future improvements to the course are considered. The various teaching methods are appraised and a closer relationship between the preclinical and clinical parts of the course is advocated. The introduction to clinical procedures and the block system of clinical teaching is considered. The overemphasis of the repetitive performance of simple clinical procedures and the time taken up doing laboratory work is criticized. The teaching of general anaesthetic administration with its lack of instruction in resuscitation and other emergency measures is deplored and the removal of this from the undergraduate course is suggested. The increasing importance attached to preventive dentistry is welcomed and the unique experience in preliminary diagnosis afforded by a dental casualty department is commended. Examination techniques are discussed and a compromise between external examination and continuous internal assessment is suggested. In conclusion, the importance of the evaluation of the course in totality is stressed, so that the overall development of the student into a self-reliant, responsible and ethical professional can be assessed. The necessity of frequent review and amendment of the curriculum is advocated if it is to remain relevant to the changing requirements of dental practice.


What can be done to correct deficiencies in the undergraduate course? Teachers should cease to be mere dispensers of facts, being rather guides to sources of information. They should be ruthless in discarding from the undergraduate course all irrelevant material and material which duplicates information or technical instruction already provided in other courses. Emphasis must be transferred from the individual tooth or tissue to the total care of the patient and this may necessitate much greater cooperation and integration between courses and departments. Time can be saved by generous provision of technical and chairside assistance. Motivation of the student is best achieved by the earliest possible introduction to clinical practice and the progressive delegation to him of clinical responsibility as his skills and knowledge develop. Self instructional material must be freely available but care must be taken to preserve and develop the capacity for communication, both oral and written, by the student to his patients and his community. Transition from undergraduate to practitioner can be made easier by conducting some part of the clinical course in institutions outside the dental school or by establishing modified practices conducted by students so far as the legal provisions of each country allow.


Dental aspects of the consumption of xylitol and fructose diets. 126 voluntary test persons, divided into three groups, were put for two years on a strict diet with regard to the sweetener used (sucrose, fructose, and xylitol). The test persons were investigated in the frame of a versatile clinical, radiographical, biochemical, microbiological, and medical research plan. The consumption of the fructose and xylitol diets did not result in any pathological changes in the test persons' whole saliva,  plaque, blood, and urine samples. The consumption of the xylitol diet reduced the incidence of dental caries by approximately 90 per cent when compared to sucrose consumption. In the fructose group the reduction was 30 per cent. Xylitol consumption reduced the growth of dental plaque by 50 per cent during the whole two-year period. It also reduced the concentration of lactate in plaque and whole saliva and the ability of plaque and whole saliva to yield reducing sugars from sucrose. Simultaneously, the activity of the salivary lactoperoxidase was strongly increased. These and certain other dentally advantageous chemical changes indicated that the mechanism of the xylitol effect is dual, being partly systemic and related to a selective effect on the production of salivary enzymes and on the electrolyte concentration of whole saliva, and partly local, depressing the growth of cariogenic and certain other microorganisms.


Caries control through the use of sugar substitutes. The purpose of the paper is to describe the essential findings in two clinical trials, carried out in order to evaluate differences in the caries increment rate as influenced by various sugars. The first study involved almost complete substitution of sucrose (S) by fructose (F) or xylitol (X) during a period of 2 years. The second study comprised partial substitution, the effects of a S- or X-containing chewing gum being compared during 1 year. In the first study there were no significant differences initially between the sugar groups; 35 subjects in the S-group, 38 in the F-group, and 52 in the X-group. During the entire study 10 subjects discontinued or were excluded. After 2 years the mean increment of decayed, missed and filled tooth surfaces was 7-2 in the S-group, 3-8 in the F-group, and 0-0 in the X-group. The second study comprised initially 102 subjects, predominantly dental and medical sutdents, divided randomly into S- and X-groups. During the study 2 subjects were excluded. The subjects consumed 4-0 chewing gums per day in the S-group and correspondingly 4-8 in the X-group. The frequency of sucrose intake was 4-24 times per day in the S-group, and 4-94 in the X-group. The caries incidence assess independently by clinical and radiographical means, equalled the 1-year observations in the first study. The results show a massive reduction of the caries increment not only in relation to total, but also in connection with partial substitution of dietary sucrose and low xylitol consumption. The first study indicates fructose to be somewhat less cariogenic than sucrose. In view of the findings in the chewing gum study it is suggested that the non- and anticariogenic properties of xylitol principally depend on its lack of suitability for microbial  metabolism and the physico-chemical effects in plaque and saliva brought about through low and repeated dosage.


The assessment of needs for periodontal treatment. The purpose of epidemiology is 'to guide the administration in the provision of health services' (MacMahon and Pugh, 1970). The provision of systematic treatment of periodontal disease has been hampered by the lack of a suitable system for calculating manpower and costs involved in the treatment of population groups. Recently, the Periodontal Treatment Need System (PTNS) has been suggested to meet with these requirements (Johansen, Gjermo & Bellini, 1973: Bellini and Gjermo, 1973). The principles of the system are explained and discussed. Moreover, it is emphasized that the prevention of periodontal disease as well as caries should be the paramount goal of the public dental health services. A possible method for early diagnosis and preventive treatment of high risk subjects is suggested.


Innovations in dental education in the United States. The amount of information which dental teachers wish students to absorb creates undesirable congestion of the curriculum. Individuals learn at different rates and if the course is designed for the average student, the better students are insufficiently challenged while the poor learner is left floundering. This problem is being met by the development of flexible, individualized instruction. As a result teachers are obliged to examine critically their goals and functions. If objectives are set for each course, teaching is planned to meet the objectives and methods of evaluation developed which are meaningful to the student, many of the criticisms laid by dentists against their education will be met. During the last decade the teaching of community dentistry has been developed in almost all dental schools as has the emphasis laid on preventive dentistry. In clinical teaching students are being introduced to patient care at an earlier stage resulting in better motivation and greater enthusiasm for the earlier parts of the course. Comprehensive patient care, the importance of occlusal dysfunction, the care of the handicapped and the utilization of auxiliary personnel are other areas of increasing importance. A significant development is the growing provision for an elective period during which the student may pursue his own particular interest.


Cell-mediated immune responsiveness of patients with acute lymphocytic leukemia in remission. Children with acute lymphocytic leukemia (ALL) in remission and undergoing either chemotherapy or immunotherapy were tested for general cell-mediated immunocompetence and cell-mediated reactivity to tumor-associated antigens (TAA) using the following parameters: skin tests with recall antigens and extracts of lymphoblastoid cell lines; primary sensitization to dinitrofluorobenzene and picryl chloride; in vitro tranformation by mitogens and PPD; and lymphocyte-mediated cytotoxicity against a lymphoblastoid cell line and a panel of cryopreserved leukemic blasts. Reactivity in all assays of children on continuous chemotherapy was significantly depressed compared to similar patients later in the study. Patients on intermittent chemotherapy demonstrated much less immunodepression. The groups tested early during immunotherapy with BCG and allogeneic leukemic blasts were hyper-responsive (compared to published data) to primary sensitization with picryl chloride. Skin test reactivity to recall antigens and to tumor-derived lymphoblastoid cell lines was suppressed (as analyzed serial comparison) in this hyperimmunized group, possibly due to antigenic competition, and reactivity in all other assays was normal. The patients tested after 2-8 years of immunotherapy showed significantly higher positive skin-test responses to extracts of tumor-derived lymphoblastoid cell lines as compared to the other groups. The results of this multiphasic screen support the known effects of chemotherapy on immunocompetence. Moreover, they document the prompt return of immunocompetence with intermittent chemotherapy and during immuno-therapy. These results do not, however, indicate a striking augmentation of the immune response during immunotherapy as measured by these parameters.


The effect of larval selection on adult resistance to DDT in two strains of the mosquito Aedes aegypti (L). Evidence is presented which confirms the influence of linkage group II on adult DDT-resistance in one strain of Aedes aegypti (Bangkok-MR) but not in another strain (Bangkok-HR).


A new sex-linked mutant short wing in Aedes aegypti. A spontaneous recessive sex-linked mutant short wing has been discovered in the mosquito Aedes aegypti. It is situated less than one cross-over unit from the sex determining locus. In homozygous females, flight is impaired and the survival and fecundity is markedly subnormal. Two possible uses of this gene for genetic control operations are envisaged: (a) to provide automatic sexing of males for release and (b) enhancement of the population control potential of other available genetics systems.