A 4-year prospective study to assess peri-implant hard and soft tissues adjacent to titanium versus gold-alloy abutments in cemented single implant crowns. Cemented versus screw-retained implant-supported single-tooth crowns: a 4-year prospective clinical study. Randomized-controlled clinical trial of customized zirconia and titanium implant abutments for single-tooth implants in canine and posterior regions: 3-year results. Clinical outcome of the altered cast impression procedure compared with use of a one-piece cast. Comparison of the performance on prosthodontic criteria of several alternative alloys used for fixed crown and partial denture restorations: Department of Veterans Affairs Cooperative Studies project 147. Six-year follow-up of titanium and high-gold porcelain-fused-to-metal fixed partial dentures. Titanium for removable partial dentures (III): 2-year clinical follow-up in an undergraduate programme. Randomized controlled clinical trial of zirconia-ceramic and metal-ceramic posterior fixed dental prostheses: a 3-year follow-up. Implant-supported laser-welded titanium and conventional cast frameworks in the partially edentulous law: a 5-year prospective multicenter study. A 3-year clinical study of alternatives to high noble dental casting alloys type 3. Prospective evaluation of implants connected to teeth. Nutrient intake in partially dentate patients: the effect of prosthetic rehabilitation. All-ceramic two- to five-unit implant-supported reconstructions. A randomized, prospective clinical trial. An evaluation of the effects of two distal extension removable partial denture designs on tooth stabilization and periodontal health. Clinical comparison of postoperative sensitivity for a glass ionomer and a zinc phosphate luting cement. Tooth-implant and implant supported fixed partial dentures: a 10-year report. A randomized clinical trial of two basic removable partial denture designs. Part II: Comparisons of masticatory scores. Ceramic implant abutments for short-span FPDs: a prospective 5-year multicenter study. Alumina ceramic implant abutments used for single-tooth replacement: a prospective 1- to 3-year multicenter study. Influence of clasp design of distal extension removable partial dentures on the periodontium of the abutment teeth.
The purpose of this prospective clinical study was to compare titanium and gold-alloy abutments when used with cemented, implant-supported single-tooth crowns. For 4 years following prosthodontic rehabilitation, these abutments were evaluated with respect to peri-implant marginal bone levels and peri-implant soft tissue parameters.
                During the years 1998 to 2000, 20 patients were selected from a patient population receiving treatment in the Implantology Department at the University of Padova, Italy. They all presented with single-tooth bilateral edentulous sites in the premolar/molar region with adequate bone width, similar bone height on each side, and an occlusal scheme that allowed for the establishment of identical occlusal cusp/fossa contacts on each side. Each subject received two identical implants (one in each edentulous site). One was randomly selected to be restored with a titanium abutment and a cemented implant-supported single-tooth crown, and the other was restored with a gold-alloy abutment and a cemented implant-supported single tooth crown. Data on peri-implant marginal bone levels and soft tissue parameters were collected for 4 years after abutment and crown insertion placement and analyzed to determine whether there was a significant (p< .001) difference with respect to the type of abutments (titanium vs. gold alloy) used.
                All subjects completed the study. All 40 implants survived, resulting in a cumulative implant success rate of 100%. Statistical analysis revealed no significant differences between the two groups with respect to peri-implant marginal bone levels and soft tissue parameters.
                Within the limitations of this study, the results indicate that there was no evidence of different response with the peri-implant marginal bone and soft tissue when titanium or gold-alloy abutments were used in conjunction with the cemented, single-tooth implant restorations provided for this limited patient population. There was no evidence of different behavior of peri-implant marginal bone and of peri-implant soft tissue when titanium abutments or gold-alloy abutments were used for cemented single-tooth implant restorations in this limited patient population. The purpose of this controlled prospective clinical study was to compare cemented and screw-retained implant-supported single-tooth crowns followed for 4 years following prosthetic rehabilitation with respect to peri-implant marginal bone levels, peri-implant soft tissue parameters, and prosthetic complications.
                Twelve consecutive patients were selected from a patient population attending the Implantology Department at the University of Padova. They all presented with single-tooth bilateral edentulous sites in the canine/premolar/molar region with adequate bone width, similar bone height at the implant sites, and an occlusal scheme that allowed for the establishment of identical occlusal cusp/fossa contacts. Each patient received 2 identical implants (1 in each edentulous site). One was randomly selected to be restored with a cemented implant-supported single-tooth crown, and the other was restored with a screw-retained implant-supported single-tooth crown. Data on peri-implant marginal bone levels and on soft tissue parameters were collected 4 years after implant placement and analyzed to determine whether there was a significant difference with respect to the method of retention (cemented versus screw-retained).
                All patients completed the study. All 24 implants survived, resulting in a cumulative implant success rate of 100%. Statistical analysis revealed no significant differences between the 2 groups with respect to peri-implant marginal bone levels and soft tissue parameters.
                The data obtained with this study suggested that the choice of cementation versus screw retention for single-tooth implant restorations is likely not based on clinical results but seems to be based primarily on the clinician's preference.
                Within the limitations of this study, the results indicate that there was no evidence of different behavior of the peri-implant marginal bone and of the peri-implant soft tissue when cemented or screw-retained single-tooth implant restorations were provided for this patient population. The aim was to test whether or not zirconia abutments exhibit the same survival and technical/biological outcome as titanium abutments.
                Twenty-two patients receiving 40 single-tooth implants in canine and posterior regions were included. The implant sites were randomly assigned to 20 zirconia and 20 titanium abutments. All-ceramic and metal-ceramic crowns were fabricated. At baseline, 6, 12 and 36 months, the reconstructions were examined for technical and biological problems. Probing pocket depth (PPD), plaque control record (PCR) and bleeding on probing (BOP) were assessed at abutments (test) and analogous contralateral teeth (control). Standardized radiographs of the implants were made and the bone level (BL) was measured referring to the implant shoulder on mesial (mBL) and distal sides (dBL). The difference of color (DeltaE) of the peri-implant mucosa and the gingiva of control teeth was assessed with a spectrophotometer. The data were statistically analyzed with Mann-Whitney Rank and Student's unpaired t-tests.
                Eighteen patients with 18 zirconia and 10 titanium abutments were examined at a mean follow-up of 36 months (range 31.5-53.3 months). No fracture of an abutment or loss of a reconstruction was found. Hence, both exhibited 100% survival. At two metal-ceramic crowns supported by titanium abutments chipping of the veneering ceramic occurred. No difference of the biological outcome of zirconia and titanium abutments was observed: PPD (meanPPD(ZrO(2)) 3.2 +/- 1 mm, mPPD(Ti) 3.4 +/- 0.5 mm), PCR (mPCR(ZrO(2)) 0.1 +/- 0.2, mPCR(Ti) 0.1 +/- 0.2) and BOP (mBOP(ZrO(2)) 0.4 +/- 0.4, mBOP(Ti) 0.2 +/- 0.3). Furthermore, the BL was similar at implants supporting zirconia and titanium abutments (mBL(ZrO(2)) 1.7 +/- 1, dBL(ZrO(2)) 1.6 +/- 1; mBL(Ti) 2 +/- 1, dBL(Ti) 2.1 +/- 1). Both, zirconia and titanium abutments induced a similar amount of discoloration of the mucosa compared with the gingiva at natural teeth (DeltaE(ZrO(2)) 9.3 +/- 3.8, DeltaE(Ti) 6.8 +/- 3.8).
                At 3 years, zirconia and titanium abutments exhibited same survival and technical, biological and esthetical outcomes. An altered cast impression procedure to improve the support of distal extension removable partial dentures is widely taught, but not often used in dental practice.
                The purpose of this study was to determine the efficacy of an altered cast compared to a one-piece cast with regard to base support, abutment health, and patient comfort over time.
                Seventy-two patients receiving a mandibular bilateral distal extension removable partial denture were assigned randomly for treatment using either a one-piece or an altered cast. All impressions and associated laboratory procedures were made by one investigator. A second investigator evaluated extension, support, and adaptation of the denture bases by observation of border length and lifting of the indirect retainer from its seat. The space between the soft tissues and the base when the framework was related to the teeth was measured cross-sectionally at half the length of the denture base. Mobility, gingival index, and sulcus depths at 6 locations around each abutment tooth were recorded at insertion and again 1 year later. Chi-square tests were used to evaluate differences between the treatment groups (alpha=.05).
                There was 0.15 mm less space between the ridge crest and base in the altered cast group (P<.01), and underextension of the base occurred only in the one-piece cast group (P=.01). At insertion, no tissue-ward movement was observed in 85% of the prostheses when anterior-posterior rotation was attempted. Fifteen subjects (21%) were lost to recall at 1 year, but they were distributed equally between the 2 groups. Of the remaining 57 prostheses, 42% exhibited decreased base support and 33% had increased gingival inflammation; the deepest probing depth decreased in 61%, mobility decreased or remained the same in 80% of the direct abutments, and 88% of the subjects were satisfied. None of these findings were related to the impression procedure.
                The altered cast impression procedure does not offer significant advantages over the one-piece cast, provided the standards used in this study are met. These include a completely extended impression, use of magnification to adjust and ensure complete seating of the framework, and coverage of the retromolar pad and buccal shelf by the base. In a 10-year, multicenter, double-blind clinical trial, comparisons of the clinical behavior of crown and fixed partial denture restorations were made between a gold alloy and four less costly alternative alloys. The endpoints of interest were (1) the development of unacceptable ratings on any of 11 individual prosthodontic criteria and an overall rating, (2) the removal of the restoration, and (3) an event combining unacceptable overall rating and restoration removal. Each of 630 patients had two restorations completed, one from gold-palladium alloy and the other from one of four alternative alloys. The patients were enrolled during a period of 3 1/2 years, with some patients followed up as long as 10 years after restoration. Analysis of the endpoints showed that one of the alternative alloys was significantly poorer than the other materials for certain criteria. In a randomized clinical study 47 titanium and gold-alloy fixed partial dentures (FPDs) were placed during a 1-year period. In the titanium group (n = 22) all metal substructures were made of unalloyed titanium. The titanium substructures were fabricated by copy milling, spark erosion and laser welding (Procera, Nobelpharma). Ceramic veneering was carried out with Duceratin titanium ceramics (Ducera, Germany). In the control group (n = 25) the high-gold alloy Degudent U (Degussa, Germany) and Vita VMK 68 ceramics (Vita, Germany) were used. The longest observation time was 6 years. Only one FPD had to be removed due to metal-ceramic failure (titanium group). The clinical performance of all 125 porcelain-fused-to-metal (PFM) veneers with respect to the longevity of the metal-ceramic compound was described by Kaplan-Meyer survivor analyses. Relating survival to a completely intact ceramic veneer, the 5-year survivor rate was 84% for titanium and 98% for the high-gold alloy. PFM titanium restorations exhibited a significantly increased risk of metal-ceramic failure. However, concerning defects requiring removal, no significant differences in titanium versus high-gold alloy occurred. There were no significant differences in the survival distributions between crowns and pontics within the two groups. This study examined the success of titanium (Ti) removable partial dentures (RPDs) compared with that of cobalt-chromium (Co-Cr) RPDs using a randomized controlled clinical trial. Thirty-eight RPD patients were provided with either Co-Cr (20 patients) or Ti (18 patients) RPDs. The total numbers of dentures was 31 (13 maxillary, 18 mandibular) for Co-Cr and 23 (11 maxillary, 12 mandibular) for Ti. Patients were reviewed for 24 months following denture issue. After the initial 12 months, 20 clinical problems were recorded and became the criteria for subsequent assessment. Incidence of failure was analysed using both Fisher's exact test and the chi square test at a significance level of P<0.05. Fracture of retainers in both metals occurred only in the first 12 months. Some failure types presented at significantly higher levels in the first 12 months but there were no significant differences between the two in all the criteria examined between the 12- and the 24-month reviews. Although differences existed in failure types between Co-Cr and Ti RPDs during the early review stages, the overall success rate of Ti RPDs was comparable with that of Co-Cr RPDs after 24 months. The higher incidence of failures in Ti RPDs prior to the 12-month review suggests the importance of taking its lower rigidity into account when designing RPDs. The aim of this study was to test whether posterior fixed dental prostheses (FDPs) with zirconia frameworks exhibit similar survival rates and technical and biologic outcomes as those with metal frameworks.
                Fifty-nine patients in need of 76 FDPs replacing one to three posterior teeth (molars and premolars) were included in the study. The three- to five-unit FDPs were randomly assigned to 38 zirconia-ceramic and 38 metal-ceramic FDPs. At baseline, 6 months, and 1 to 3 years after cementation, the technical outcome of the reconstructions was examined using the United States Public Health Service (USPHS) criteria. The biologic outcome was analyzed at test (abutment) and control (contralateral) teeth by assessing: probing pocket depth (PPD), probing attachment level (PAL), plaque control record (PCR), bleeding on probing (BOP), and tooth vitality. Radiographs of the FDPs were made. Statistical analysis was performed by applying Kaplan-Meier, Pearson chi-square, Fisher exact, and Mann-Whitney U tests.
                Fifty-three patients with 67 FDPs (36 zirconia-ceramic, 31 metal-ceramic) were examined after a mean observation period of 40.3 +/- 2.8 months. Six patients with 9 FDPs were lost to follow-up. The survival of both kinds of FDPs was 100%. No significant differences regarding the technical and biologic outcomes were found. Minor chipping of the veneering ceramic was found in 25% of the zirconia-ceramic and 19.4% of the metal-ceramic FDPs. Extended fracturing of the veneering ceramic occurred solely in zirconia-ceramic FDPs (C: 8.6%, D: 2.8% [USPHS criteria]). Few biologic complications were found. Both types of FDPs rendered the same mean values for the biologic parameters (mean PPD, PCR, and BOP for zirconia-ceramic FDPs = 2.4 +/- 0.3, 0.1 +/- 0.1, and 0.3 +/- 0.2, respectively; mean PPD, PCR, and BOP for metal-ceramic FDPs = 2.4 +/- 0.3, 0.1 +/- 0.1, and 0.3 +/- 0.2, respectively).
                Zirconia-ceramic FDPs exhibited a similar survival rate to metal-ceramic FDPs at 3 years of function. This study evaluated and compared the clinical performance of laser-welded titanium fixed partial implant-supported prostheses with that of conventional cast frameworks in the partially edentulous jaw.
                Forty-two patients provided with Brånemark system implants were arranged into two groups. Twenty-one patients (group A) were provided with a conventional cast ceramometal framework in one side of the jaw and a laser-welded titanium framework with low-fusing porcelain in the other side. In group B, 21 patients received a titanium framework prosthesis to replace a conventional implant prosthesis. Clinical and radiographic data were collected for 5 years.
                Four implants and one titanium framework were lost during the follow-up period. The two framework designs did not show any significant differences with regard to implant or prosthesis survival (P > .05). Few clinical complications were observed. In group A, marginal bone loss after 5 years was similar for both prosthesis designs, with an average of 0.1 mm and 0.3 mm in the maxilla and mandible, respectively. Basically, no bone loss was observed on average in group B. Furthermore, no significant relationship was observed between marginal bone loss and placement of prosthesis margin or prosthesis design.
                Except for an insignificant tendency toward a slightly higher incidence of small chips of porcelain veneers, laser-welded titanium frameworks presented an overall similar clinical performance as conventional cast frameworks in partial implant situations after 5 years. For the purpose of evaluating the quality of dental casting alloys, 22 patients were recalled for clinical examination 3 years after insertion of crowns and bridges made from the low-gold alloy Midas and the silver-palladium alloy Albacast. A high-gold alloy, JS C, served as a reference alloy. The examination included registrations of tarnish, plaque index, gingival index, and margin index. In addition, the California Dental Association's quality evaluation of dental care was used by two independent calibrated examiners. From the results of the present study it can be concluded that the crowns made from the alloy Midas in the annealed condition and the alloy Albacast are well suited for clinical use. Some tarnish appeared, but this may occur intermittently. This prospective clinical trial examined the effect on teeth and implants when rigidly or non-rigidly connected in a cross-arch model.
                Thirty patients received 2 implants, 1 on each side of the mandible, and were restored with 3-unit fixed partial dentures connected either rigidly or non-rigidly to an abutment tooth. Patients were followed for at least 5 years post-restoration.
                Repeated-measures analysis revealed no significant difference in crestal bone loss at implants (rigid versus non-rigid methods). An overall significant difference (P < .001) was found comparing methods for teeth. Paired t tests revealed no significant differences in crestal bone levels for implants or teeth at the 5-year recall. Kaplan-Meier methods and the Cox proportional hazards model showed no differences between attachment methods with regard to success based on survival and bone loss criteria. During the 5-year recall period, 1 implant (rigid side) was removed. Four implants developed bone loss greater than 2 mm during the course of this trial. One tooth on the rigid side and 2 teeth on the non-rigid side had greater than 2 mm of crestal bone loss and were removed secondary to fractures. In all, 5 abutment teeth were removed, all of which had been treated with root canal therapy and fractured at the interface of the post within the tooth. There was no clear relationship of tooth fracture to attachment. Repeated-measures analysis of mobility values revealed no significant changes over the time course of this study, and paired t tests revealed no statistically significant differences between implants for mobility. Repeated-measures analysis and paired t tests for probing depth revealed no significant changes over the time course of this study. There were no significant differences in soft tissue indices for either attachment method. The percentage of patients who had measurable intrusion was 66% for the non-rigid group, and 44% for the rigid group; 25% of the non-rigid teeth had greater than 0.5 mm intrusion, compared with 12.5% for the rigid group. For the 2 time periods evaluated, there was no significant increase in intrusion over time. The non-rigid-side implant required more nonscheduled visits to treat problems than the rigid implant and the teeth. Discussion: Most patients were treated successfully with rigid or non-rigid attachment of implants to teeth.
                The high incidence of intrusion and non-scheduled patient visits suggest that alternative treatments without connecting implants to teeth may be indicated. The objectives of this study were to investigate the impact of prosthetic rehabilitation of the shortened dental arch on the intake of nutrients, non-starch polysaccharide (NSP) fruits and vegetables (dietary fibre), and to compare dietary intakes between patients receiving bilateral resin-bonded bridges with patients receiving conventional partial dentures.
                As part of an ongoing randomised clinical trial to compare the effectiveness of bilateral resin bonded bridges with conventional partial dentures, the diets of 40 partially dentate patients were assessed prior to and at 3 and 12 months following treatment with bilateral resin-bonded bridge-work or a lower partial denture.
                At baseline, three months post treatment and one year post treatment there were no significant differences in the intake of nutrients between groups. A significant increase in the percentage of energy from fat was observed in the patients fitted with a lower partial denture. Apart from this, prosthetic rehabilitation did not result in any other change in the intake of nutrients or in the amount of fruits and vegetables consumed. Levels of intake of NSP, fruits and vegetables were low in both groups of patients on all occasions measured.
                Prosthetic rehabilitation of the severely shortened dental arch does not result in dietary improvements. Dietary advice that takes into account all the factors that influence food choice (such as taste, cost and cooking skills) needs to be considered in this at risk group. The purpose of this study was to evaluate the clinical performance of two to five-unit implant-supported all-ceramic reconstructions and to compare the results of two different all-ceramic systems, Denzir (DZ) and In-Ceram Zirconia (InZ). Eighteen patients were treated with a total of 25 two- to five-unit implant-supported reconstructions. Nine patients were given reconstructions of the DZ system and the other nine reconstructions of the InZ system. The reconstructions were cemented with zinc phosphate cement onto preparable titanium abutments and were evaluated after 6 and 12 months. At the 12-month follow-up, all reconstructions were in function; none had fractured. Superficial cohesive (chip-off) fractures were, however, observed in 6 of the 18 patients (8 of 25 reconstructions). Nine units in the DZ group (in 7 of 13 reconstructions) and one in the InZ group (1 of 12 reconstructions) had chip-off fractures. The difference between the two groups regarding frequency of chip-off fractures was statistically significant (P < 0.01). Marginal integrity was rated excellent at 34 abutments (56%) and acceptable at 27 (44%). Results from this 12-month trial suggest that all-ceramic implant-supported fixed partial dentures of two- to five-units may be considered a treatment alternative. When comparing the two ceramic systems under study, however, this study concludes that the DZ system exhibits an unacceptable amount of veneering porcelain fractures and thus cannot be recommended for the type of treatment evaluated in this trial. Further studies and long-term follow-ups must be performed before the materials and technique can be recommended for general use. A 30-month follow-up study was conducted on 36 patients to evaluate the effects of the lingual plate as a major connector in distally extended removable partial dentures (RPDs) on tooth stabilization. At the same time, the study evaluated the effects of lingual plate-type RPDs and lingual bar-type RPDs on periodontal health. The most striking finding of the study was that, with the exception of gingival recession (GR), periodontal conditions improved with both types of RPDs. At the end of 30 months, there were significant differences in plaque index, GR and tooth mobility (TM) values between treatment groups (P < 0.05). Plaque accumulation was greater in the lingual plate treatment group; however, this did not result in periodontal breakdown. There were no statistically significant differences between treatment groups with respect to pocket depth, gingival index or attachment loss (P > 0.05). Moreover, patients treated with lingual plate-type RPDs demonstrated less TM when compared with patients treated with lingual bar-type RPDs at the end of 30 months follow-up. Overall study findings established that with adequate checks on oral and denture hygiene at regular intervals, patients with RPDs may even experience improved periodontal health. Moreover, the clinical interpretation of decreased TM observed in patients treated with lingual plate-type RPDs may be questionable as the plaque accumulation was greater in the lingual plate treatment group inspite of periodic recalls. In 60 patients, 120 partial and full-coverage restorations were cemented on vital abutment teeth with either a glass ionomer or a zinc phosphate luting cement. A split-mouth design and a patient blind data acquisition protocol were used. During an average observation period of 17.3 months there were no differences between the two types of luting cements in regard to subjective and clinical parameters. A high incidence of postoperative hypersensitivity, which is often said to accompany the use of glass ionomer luting cements, was not observed. With the cementation method used in this study, the glass ionomer cement Ketac-Cem Maxicap was an acceptable alternative to conventional zinc phosphate cement. Capsule systems make the clinical handling of glass ionomer luting cements safe and easy and should be used routinely in dental practice. The use of implants for prosthetic rehabilitation of partially edentulous patients is increasing. However, the possibilities of placing implants in the posterior part of the mandible are often limited. The purpose of this longitudinal study with 10 years of follow-up was to evaluate the use of short implants supporting fixed partial dentures (FPD) in the posterior part of the mandible, and to compare implant supported FPDs to tooth-implant supported FPDs.
                The patient material comprised 23 patients with residual mandibular anterior teeth, and each patient received FPDs unilaterally. On one side the FPD was supported by two implants, and on the other side by one implant and one tooth, thus permitting intraindividual comparison. The distribution of the two types of FPDs in each jaw was randomized. Implant success rates, marginal bone changes, and mechanical complications were studied.
                The tooth-implant connection did not demonstrate any negative influences on the overall success rates for the 10-year period, nor were the shorter implants found to be less favorable.
                It is suggested that a prosthetic construction supported by both a tooth and an implant may be recommended as a predictable and reliable treatment alternative in the posterior mandible. There is no known data on the functional efficacy of different removable partial denture designs.
                This randomized clinical trial compared the masticatory performance of two commonly used designs in 118 patients who needed a unilateral or bilateral mandibular partial denture.
                One half of the patients received a partial denture with distal occlusal rests and cast circumferential clasps and the other half a partial denture with mesial rests and I-bar cast clasps. The left side, right side, and swallowing threshold masticatory tests were made with peanuts and carrots before treatment and 16 weeks after the prosthesis insertion (baseline) and thereafter at 6, 18, 36, and 60 months.
                Masticatory scores at entry were higher in the circumferential design group, but the only significant (p < 0.05) difference was found in the right side carrot performance. Both groups realized significant improvements (p < 0.001) in all performance scores with partial dentures. Mean improvements of 24.7 with peanuts and 35.8 with carrots in the right side performance scores and 19.0 in the swallowing threshold score with peanuts in the bar design group were significantly higher (p = 0.017) than the respective mean improvements of 15.9, 21.4, and 5.6 in the circumferential design group. However, no significant differences were found between the two groups for any of the 10 performance scores at baseline.
                Despite some performance differences at entry, the mean performance scores for the two groups became similar at baseline and at subsequent intervals. A prospective, randomized, controlled 5-year multicenter study evaluated the long-term clinical function of CerAdapt ceramic abutments compared to titanium abutments on Brånemark implants supporting short-span fixed partial dentures (FPD).
                Initially, 105 Brånemark implants were placed in a total of 32 patients at three different clinics; 103 implants remained after initial healing. Fifty-three ceramic and 50 titanium abutments were connected to support 36 FPDs, 19 on ceramic and 17 on titanium abutments.
                Thirty patients with 29 FPDs were examined after 5 years. There was a cumulative success rate of 97.2% for FPDs (94.7% for ceramic and 100% for titanium abutment-supported FPDs). One of 53 ceramic and none of 50 titanium abutments failed, giving survival rates of 98.1% and 100%, respectively. There was a mean marginal bone loss of 0.3 mm and 0.4 mm, respectively, for ceramic and titanium abutments. Soft tissues around abutments and adjacent teeth appeared healthy, and no significant differences were recorded for mucosal bleeding and plaque between ceramic and titanium abutments. Crown margins at FPD insertion were positioned as follows: 21% submucosally, 33% at the mucosal margin, and 46% supramucosally. Changes in mucosal level were recorded at 12% of the abutments, with 73% of all changes recorded at ceramic abutments. There was a balance between more or less exposed crown margins during the first 2 years, in contrast to the 2- to 5-year period, when all changes meant less exposed margins.
                Safe long-term functional and esthetic results can be achieved with CerAdapt alumina ceramic abutments on Brånemark implants for short-span FPDs. The aim of the study was to compare results after 1 and 3 years when single crowns supported by CerAdapt (test) ceramic abutments or CeraOne (control) titanium abutments were loaded.
                The material was divided into two groups: in group A, 69 (34 test, 35 control) abutments/crowns from all involved clinics were followed for 1 year; and in group B, 20 (10 test, 10 control) abutments/crowns from one of the clinics were followed for 3 years.
                No implant failed, giving a cumulative success rate of 100% for the implants. Two CerAdapt abutments in group A fractured, giving a cumulative success rate of 93% for the CerAdapt and 100% for the CeraOne abutments after 1 year. No abutment failed in group B, giving a cumulative success rate of 100% both for the CerAdapt and the CeraOne abutments between 1 and 3 years. The CerAdapt fractures might have been due to the fact that the abutments were impaired through too-extensive preparation and/or had been exposed to a too-high bending moment. Almost no marginal bone loss was recorded, indicating a stable bone situation both at CerAdapt and CeraOne abutments on single-tooth implants. Healthy conditions, with a relatively stable level of the periimplant mucosa in relation to the abutment/crown, were recorded for soft tissues both at CerAdapt and CeraOne abutments. Both clinicians and patients rated the esthetic result as excellent for practically all cases.
                The results demonstrate the esthetic possibilities and the safety of single-tooth replacement when accepted treatment concepts are followed and documented components are used. The tested abutments worked well, although the fractured CerAdapt abutments indicate that ceramic abutments are more sensitive to handling procedures than the titanium abutments. Three removable partial denture designs were investigated to determine the effect of minor connector configuration on the periodontal health of abutment teeth. Twenty-five patients wore three different removable partial dentures for 19 weeks each. The first removable partial denture placed a tilting force on the abutment teeth; the second was stress-releasing; and the third collected the least amount of plaque. Plaque accumulation, the condition of the periodontium, migration of the abutment teeth, deformation of the clasp arms, retention of the prosthesis, and patient preferences were assessed. The results demonstrated that the partial denture retentive design did not affect plaque formation. The prosthesis designed to place a tilting force on the abutment teeth appeared to cause the least mobility and migration of the abutments and had the greatest acceptance by the patients.
Based on trials meeting the inclusion criteria for this review, there is insufficient evidence to recommend a particular method of tooth replacement for partially edentulous patients.