Survival rate and need for maintenance of cover-denture prostheses borne on three or less abutment teeth: ten-year results.

This study aimed to evaluate the effects of endodontic treatment on the complication rate in abutment teeth following double crown treatment. Data of 233 patients supplied with 278 prostheses on 773 teeth were retrospectively analyzed. The 60-month cumulative complication rate for vital, root filled, and post and core reconstructed abutment teeth is calculated using the Kaplan-Meier method. Cox regression is performed to evaluate factors including age, sex, jaw, and tooth number. After 60 months, the cumulative complication rate for all abutment teeth was 24.1% (CI: 19.7-28.5%). A significantly higher cumulative fracture rate (log-rank test, p < 0.001) was found for devital (51.7%; CI: 35.3-68.1%) compared to vital abutment teeth (20.6%; CI: 16.2-25%). Devital teeth restored with post and core reconstructions (46.3%; CI: 26.1-66.5%) showed a lower cumulative fracture rate than abutment teeth with only root fillings (60.9%; CI: 33.5-88.3%). Abutment teeth in severely reduced dentitions (≤ 3 teeth) were found to have significantly lower survival rates than abutment teeth in not severely reduced dentitions (≥ 4 teeth, p = 0.031, HR = 0.609). Lower abutment teeth survival rates were associated with non-vitality and a reduced number of abutment teeth. Devital teeth with post and core reconstructions showed higher survival rates than root filled devital teeth. After 5 years, devital teeth with double crowns have a fracture rate twice as high as vital teeth. This prognosis should be taken into account during treatment planning, especially in the severely reduced dentition.

Fifteen-year outcome of three-unit fixed dental prostheses made from monolithic lithium disilicate ceramic

ObjectivesThis follow-up study aimed at collecting long-term data for removable partial dentures (RPDs) retained by double crowns with spark-eroded friction pins (DCP) and comparing them in the presence of severely reduced dentition (SRD) and non-SRD (NSRD, i.e. residual dentition with more than three abutment teeth) after a 10-year wearing period.Materials and methodsA total of 158 participants (n = 71, 44.9% women) aged 62.5 ± 12.7 years with 182 prostheses on 520 abutment teeth were followed up between 2006 and 2022. The SRD group included 144 RPDs supported by 314 abutment teeth. The data collection was performed retrospectively. 10-year survival rates of RPDs and abutment teeth were determined using the Kaplan–Meier method and compared using the log-rank test for SRD and NSRD, among others. Cox regression analyses were conducted to isolate risk factors for the survival of both RPDs and abutment teeth.ResultsThe 10-year cumulative survival rate of all abutment teeth was 65.6% with significantly lower values in the SRD group (53.5%) (p < 0.001). The survival rate for all RPDs was 65.5%. The SRD group showed lower survival rates (57.9%) (p = 0.004). The number and location of the abutment teeth had a significant influence on the survival rates of the RPDs and the abutment teeth. Age, sex, jaw, relining, and vitality had a significant influence on the abutment teeth survival rates.ConclusionsRPDs showed an acceptable clinical survival rate after 10 years. The number, location, and vitality of abutment teeth were factors that influenced the survival of both RPDs and abutment teeth.Clinical relevanceConsideration of the influencing factors found can help improve the prognostic assessment of double crown-retained dentures in the context of prosthetic therapy planning.

In subjects suffering from generalized severe periodontitis, only a few teeth may be treated and used as abutments for fixed dental prostheses (FDPs). To systematically review the impact of severely reduced, but healthy periodontal tissue support on the survival rate and complications of FDPs after a mean follow-up time of at least 5 years. Publications considered for inclusion were searched in MEDLINE (PubMed) and relevant journals were hand searched. The search was performed in duplicate and was limited to human studies published in the dental literature from 1966 up to and including September 2006. Only publications in English, in peer-reviewed journals, were considered. Abstracts were excluded. Prospective and retrospective cohort studies were included. The primary outcome measure included survival rates of FDPs and abutment teeth, whereas biological and technical complications of FDPs and abutment teeth represented secondary outcome measures. Summary estimates of survival rates and of biological and technical complications were calculated after 5 and 10 years. The search provided 860 titles of which six publications were included. A total of 579 FDPs were incorporated and followed up to 25 years. Meta-analysis yielded an estimated FDP survival rate of 96.4% [95% confidence interval (95% CI): 94.6-97.6%] after five and of 92.9% (95% CI: 89.5-95.3%) after 10 years, respectively. After 10 years, the estimated rate of abutment teeth without endodontic complications amounted to 93% (95% CI: 62.6-98.9%). The 10-year estimated rate of caries-free abutment teeth was 98.1% (95% CI: 88.2-99.7%). FDPs without loss of retention were estimated to occur in 95.4% (95% CI: 92.6-97.2%) of cases after 10 years. These results showed that (i) masticatory function could be established and maintained in subjects receiving FDPs on abutment teeth with severely reduced but healthy periodontal tissue support and (ii) FDPs survival rates compared favourably with those of FDPs incorporated in subjects without severely periodontally compromised dentitions.

ObjectivesSeveral in vitro studies have investigated the retention of double crowns with friction pins (DCP); however, clinical data on their long-term success have not been reported. We sought to evaluate the 5-year survival rate of DCPs in patients with severely reduced dentition (SRD) and not severely reduced dentition (NSRD).Materials and methodsA total of 158 patients were treated with 182 dentures on 520 abutment teeth between 2006 and 2016. The SRD group included 144 dentures that had been inserted on 314 abutment teeth. We evaluated the influence of age, sex, jaw, number, tooth vitality, and abutment teeth localization (according to Steffel’s classification) on the 60-month survival rates of dentures and abutment teeth using the Kaplan-Meier estimator, logrank test, and Cox regression.ResultsThe cumulative 60-month survival rate was 84.3% (CI 77.1–91.5%) for all dentures; however, the survival rate in the SRD group (80.3%; CI 71.5–89.1%) was significantly lower than in the NSRD group (100%; p = 0.04). Dentures classified in Steffel’s class A had the lowest survival rate (51.5%; CI 30.9–72.1%). Number, location, and vitality of the abutment teeth had a significant impact on survival rate.ConclusionsDCP dentures showed comparable clinical long-term success to double crown systems that have been previously reported in the literature. The number, localization, and vitality of abutment teeth had the greatest influence on the survival rates of denture and abutment teeth.Clinical relevanceDCP dentures have an acceptable 5-year survival rate. Clinical treatment planning must take into account key factors associated with the prognosis of the abutment teeth.

Retrospective evaluation of the clinical performance of tooth-supported overdentures retained by resilient telescopic crowns with occlusal clearance fit (ODRTC) in severely reduced dentition (1-3 remaining teeth). A total of 313 ODRTCs were inserted in an undergraduate prosthodontic program (University Medical Center, Goettingen, Germany) between 2000 und 2012. Data regarding 263 ODRTCs in 221 patients were reevaluated (observational period: 64.5 ± 34.8months), and time-dependent survival and success rates (Kaplan-Meier-Estimator) were calculated. The number of the abutment teeth was analyzed as an influencing factor (Cox regression model (p < 0.05)). The 5- and 8-year overdenture survival rates were 62% [CI: 0.55; 0.69] and 38% [CI: 0.30; 0.45]. The 5- and 8-year success-rates (biologically and technically event-free restorations) were 13% [CI: 0.09; 0.17] and 3% [CI: 0.01; 0.05]. On the abutment level, the 5- and 8-year survival rates were 55% [CI: 0.48; 0.62], and 34% [CI: 0.27; 0.42]. The number of abutment teeth significantly influenced the overdenture and abutment survival rates. Restorations with 1 or 2 abutments were significantly associated with an increased number of technical and biological complications (decementation of the primary crown, abutment fracture) compared to ODRTCs with 3 abutments. The survival and success rates of ODRTCs are significantly influenced by the number of abutments. For ODRTCs, reduced survival and success rates are expected, especially when only 1 or 2 abutment teeth are included.

The objective of this review was to systematically screen the literature for data related to the survival and complication rates observed with dental or implant double crown abutments and removable prostheses under functional loading for at least 3 years. A systematic review of the dental literature from January 1966 to December 2009 was performed in electronic databases (PubMed and Embase) as well as by an extensive hand search to investigate the clinical outcomes of double crown reconstructions. From the total of 2412 titles retrieved from the search, 65 were selected for full-text review. Subsequently, 17 papers were included for data extraction. An estimation of the cumulative survival and complication rates was not feasible due to the lack of detailed information. Tooth survival rates for telescopic abutment teeth ranged from 82.5% to 96.5% after an observation period of 3.4 to 6 years, and for tooth-supported double crown retained dentures from 66.7% to 98.6% after an observation period of 6 to 10 years. The survival rates of implants were between 97.9% and 100% and for telescopic-retained removable dental prostheses with two mandibular implants, 100% after 3.0 and 10.4 years. The major biological complications affecting the tooth abutments were gingival inflammation, periodontal disease, and caries. The most frequent technical complications were loss of cementation and loss of facings. The main findings of this review are: (I) double crown tooth abutments and dentures demonstrated a wide range of survival rates. (II) Implant-supported mandibular overdentures demonstrated a favorable long-term prognosis. (III) A greater need for prosthetic maintenance is required for both tooth-supported and implant-supported reconstructions. (IV) Future areas of research would involve designing appropriate longitudinal studies for comparisons of survival and complication rates of different reconstruction designs.

The goal of this study was to determine the survival rate, success rate, and periodontal health quality (PHQ) of glass fiber-reinforced composite (FRC) resin-bonded fixed dental prostheses (RBFDPs) over an observation period of up to 22 years. RBFDPs reinforced with unidirectional glass fiber strands were fabricated directly (n = 16) or indirectly (n = 31; *n = 1 missing data) for 48 adult patients (24 female, 24 male) and used to replace 39 anterior teeth and 9 posterior teeth in the maxilla (n = 33) or mandible (n = 15) using different framework designs: single-retainer (n = 8), double-retainer (n = 33), or multi-retainer (n = 7). Their fate was classified as a success, functional survival, or failure based on observed complications. PHQ was evaluated by measuring PPD, CAL, SBI, and PI around the abutment teeth and unrestored reference teeth (controls). The clinical quality of the restorations was evaluated according to the Fédération Dentaire Internationale (FDI) criteria. Statistical analysis included Kaplan-Meier survival analysis, Wilcoxon tests, Mann-Whitney U tests, and Chi-squared tests. The significance level was set at P 0.05 for all statistical tests. The outcome was 'failure' in 37 cases (52.9%), 'functional survival' (at a mean follow-up of 9 years) in 15 cases (25.7%), and 'success' in 18 cases (25.7%). The median time to first complication was 32.0 months. The most common complications were debonding and fracture. Multi-retainer FRC-RBFDPs had the highest complication rates. Most FRC-RBFDPs were of good clinical quality according to FDI criteria. PHQ scores showed significantly higher clinical attachment level (CAL) (pw = 0.027) around abutments (3.40 ± 1.42/controls: 3.09 ± 1.11) and significantly greater plaque accumulation around abutments (pw = 0.008, 3.28 ± 1.03/controls: 2.83 ± 1.02) and pontics (pw = 0.001, 3.50 ± 0.99/controls: 2.83 ± 1.02) than around control teeth. Pocket probing depth (PPD) values were lower for abutments (2.43 ± 0.49) than for control teeth (2.52 ± 0.55). The opposite was true for sulcus bleeding index (SBI) scores (abutments: 0.64 ± 0.76/controls: 0.42 ± 0.71). There were no significant differences in periodontal health variables between younger and older restorations. In group comparisons, mean and median PPD, CAL, and plaque index (PI) scores for abutment and control teeth were higher in older patients than in younger patients. Based on our survival and complication data, FRC-RBFDPs can be considered short- to medium-term restorations. A 5-year survival rate of approximately 80% can be expected. The most common complications were reparable defects. Thus, repairs can prolong the survival time in many cases. Patient age had a greater effect on PHQ than restoration age. For example, FRC-RBFDPs in older patients were associated with higher levels of plaque accumulation and gingival inflammation around abutments, suggesting that older patients have greater difficulty cleaning the resin-bonded bridge area.

To investigate the risk factors related to failure of removable partial dentures (RPDs) and to compare the survival of RPDs when abutment teeth have good vs reduced bone support. In this longitudinal patient record-based cohort study with a mean follow-up of 44.9 months, Cox regression models were used to evaluate the associations between clinical covariates and abutment tooth failure, as well as prosthesis failure. A total of 142 patients and 172 RPDs were included. Of the 172 prostheses, 64 (nearly 40%) failed after a mean time of about 4 years. Loss of abutment teeth was the main reason leading to RPD failure, followed closely by poor fit and adaptation. No factor was shown to be statistically significant at the prosthesis level. Women (Hazard Ratio [HR] = 0.542), endodontic treatment (HR = 3.460), presence of post and core (HR = 0.302), presence of a prosthetic crown (HR = 3.403), and abutment tooth type (in relation to incisor: canine HR = 0.196, premolar HR = 0.449) were the risk factors statistically significantly associated with the loss of abutment teeth. The pre-prosthesis amount of bone support of the teeth did not affect their prognosis as abutments for RPDs. RPD treatment modality presented a high failure rate after a mean follow-up of 4 years. Vital abutment teeth had a better survival rate than the ones treated endodontically (whether restored with or without a post and core); nevertheless, the amount of bone support did not affect their survival.

A randomized controlled clinical trial of 3-unit posterior zirconia–ceramic fixed dental prostheses (FDP) with layered or pressed veneering ceramics: 3-year results

Clinical performance and patient satisfaction obtained with tooth-supported ceramic crowns and fixed partial dentures

Retrospective evaluation of complete-arch fixed partial dentures connecting teeth and implant abutments in patients with normal and reduced periodontal support

Fixed partial dentures (FPDs) made of 12% Au-Pd alloy are covered under Japan's national health insurance system. The survival rate of such 3-unit fixed FPDs remains unknown, however. The purpose of this retrospective study was to assess their survival rate in the replacement of first molars. A total of 140 FPDs were included, and the endpoint was removal of an FPD. During the observation period, 43 FPDs were removed. The FPD survival rate was 70.2% at 10 yr, 58.2% at 15 yr, and 42.1% at 20 yr according to the Kaplan-Meier method. The estimated mean survival period was 19.4 yr. The main reasons for FPD loss were dental caries (27.9%), separation from the abutment tooth (18.6%), and pulpitis (18.6%). Single factor analysis using the log-rank test showed that two factors influenced FPD survival: a smaller gonial angle and deep pockets around the abutment teeth. This effect was not statistically significant in either case, however (p>0.05). The present results suggest that the prevention of caries and of the separation of the dentures from the abutment teeth are important factors in the long-term survival of FPDs.

In a study, the effectivity and durability of telescopic dentures on abutment teeth provided with telescope crowns were investigated. The prognosis for the prosthetic structure and for the abutment teeth were both investigated. The survival rate of 234 telescopic dentures (886 abutment teeth) in 147 patients in a general dental practice were retrospectively evaluated on the basis of a status study. The mean survival rate was calculated. This is the moment when 50% of the telescopic dentures had failed. For telescopic dentures in the maxilla, this was 22.3±2.8 years, which did not represent a statistically significant difference from the mandible (20.9±1.9 years). Of the 886 abutment teeth that were used, 127 (14.3%) were extracted after an average period of 11.7 years. Periodontal complications were the primary reason for extraction. Based on this investigation, one could conclude that telescopic dentures are also a durable and sustainable solution in the long term. Loss of abutment teeth is relatively rare and has limited influence on the survival of the prosthetic structure.

There is a lack of data regarding the clinical outcome of removable partial dentures (RPDs) supported by a combination of residual natural teeth and implants placed in strategic positions. The aim of the present case series was to conduct a retrospective investigation of the clinical outcome of mandibular tooth-implant-retained partial dentures (TIRPD) rigidly retained via telescopic double crowns. Between 1999 and 2010, 18 patients with reduced residual dentition (1 to 3 natural abutment teeth) and in need of an RPD received 1 to 3 implants in strategic positions for support of the removable prostheses. All TIRPDs were rigidly retained by telescopic crowns according to the Marburg Double Crown (MDC) technique; all prostheses were placed in a private practice. Tooth/implant survival and success rates, prosthetic maintenance requirements, and peri-implant parameters were analyzed retrospectively using patient records and clinical examinations during the final recall appointments. Only patients attending at least annual supportive post-implant hygiene therapy visits (SIT) were included. After a mean functional period of 5.84 ± 3 years (range: 3.01-12.21), 14 patients with 14 dentures supported by 24 implants and 27 teeth (mean number of abutments: 3.6) were available for assessment. Four teeth (survival rate: 85.19%) and no implants (survival rate: 100%) were lost. Peri-implantitis was observed around one implant (4.17%). All 14 dentures were functional (survival rate: 100%) and required only limited maintenance (i.e., screw loosening, acrylic resin fracture repairs, relining) amounting to 0.086 treatments per patient per year (T/P/Y). Within the limitations of this case series, it can be concluded that TIRPDs retained via MDCs might represent a viable treatment option in mandibles with few remaining abutment teeth. Further long-term clinical evaluations with a greater sample size are needed for a more detailed evaluation of this treatment concept.