Long-term clinical performance of resin-bonded fixed partial dentures placed in a developing country

Debonding of cast metal-based cantilever and fixed-fixed resin-retained bridgework: A review of the literature

AIM

Cast metal-based resin-retained bridgework (RRB) offers a practical, conservative approach when restoring edentulous spaces. This review examines the debonding of cast metal-based RRB, comparing cantilever resin-retained bridgework (CRRB) and fixed-fixed resin-retained bridgework (FRRB) designs taking into context developments in RRB design, construction, and cementation over time.

METHODS

An electronic search was conducted through Medline and Embase with the aid of Boolean operators to combine the following key words: "adhesive bridges", "resin-bonded bridges", "resin-retained bridges", "resin-bonded fixed partial dentures", "cantilever", "debond", "fixed-fixed", "decementation", "failure", "success", "outcome", "longevity" and "survival". The search was limited to peer-reviewed articles written in English and published from 1995 through to 2019.

MAIN FINDINGS

Thirty-one studies were included. Five studies compared the longevity of CRRB versus FRRB, five assessed the clinical performance of CRRBs alone, and 21 studies assessed the clinical performance of FRRBs. There was great variability in study design and the reporting of clinical outcomes, and an analysis and critique of the included papers is provided. Overall, CRRB tend to debond less and hence provide longer-term and more reliable clinical service when compared to FRRB.

PRINCIPAL CONCLUSIONS

More high-level, long-term, prospective and clinical controlled trials are required to further analyse and evaluate the long-term outcomes of cast metal-based RRB.

Multi-factorial retainer design analysis of posterior resin-bonded fixed partial dentures: a finite element study

OBJECTIVES

Biomechanical aspects related to prosthesis design of RBFPD have been proposed as the predominant contributor to unpredictable clinical retention. The aim of this study was to investigate the biomechanics of multiple posterior retainer designs and their interactions using three-dimensional finite element analysis.

METHODS

To understand the interactions among the retainer design factors, three values of retainer thicknesses (1.2, 0.8 and 0.4mm), heights (100, 75 and 50% of the distance from 2mm above the CEJ to the occlusal surface) and angle of the axial surface extensions (150, 180 and 210 degrees ) were selected as the design parameters. Twenty-seven RBFPD FE models with three retainer-design parameters were created by image processing, contour stacking, and mapping mesh procedures. The maximum principal and von Mises stresses in remaining tooth and prosthesis, respectively, were recorded in 54 FE analyses (27 FE models with axial and lateral occlusal loadings).

RESULTS

The simulated results showed that the averaged stress values of the remaining tooth and prosthesis decreased with greater retainer thickness and height as a result of increasing prosthesis stiffness and maximizing of the bonding area between the enamel and the retainer, respectively. However, no significant stress differences were found according to the angle of the retainer extension because stress transmission was concentrated at the connectors.

CONCLUSIONS

The stress elevation rate (termed as VSR-stress elevation by decreasing one unit volume of the remaining tooth) addresses that the height was the most influential factor for the remaining tooth structure, followed by retainer thickness and extension angle.

Survival rates of resin-bonded, glass fiber–reinforced composite fixed partial dentures with a mean follow-up of 42 months: A pilot study

STATEMENT OF PROBLEM

Although short-term clinical data exist for resin-bonded, glass fiber-reinforced composite fixed partial dentures (FPDs), long-term data are needed.

PURPOSE

The survival rates of 29 resin-bonded, glass fiber-reinforced composite fixed partial dentures were evaluated in this clinical study for periods of up to 42 months.

MATERIAL AND METHODS

FPDs were fabricated to replace 1 to 3 missing maxillary or mandibular teeth of 29 patients not able to be treated with conventional FPDs. Originally, there were 37 patients (the drop-out rate was 22%). The FPDs were retained with wings, inlays, complete coverage crowns, or combinations of these that were bonded to tooth structure. The FPD frameworks were made of continuous unidirectional E-glass fibers with a multiphase polymer matrix and light-polymerized particulate composite veneer. The patients were recalled for examinations, where a general dental examination was performed, 1 to 3 times per year for up to 63 months (minimum 24 months, mean 42 months). Partial or complete total debonding of the FPD or the framework fracture was considered a treatment failure. The data were analyzed with the Kaplan-Meier survival test (alpha=.05).

RESULTS

Two resin frameworks fractured, and 3 frameworks were debonded. Kaplan-Meier survival probability at 63 months was 75%. Three of the failed FPDs were rebonded or repaired in situ, producing a functional survival rate of 93% after rebonding or repairing (mean survival time was 55 months).

CONCLUSION

The results of this clinical study of 29 prostheses suggest that glass fiber-reinforced FPDs may be a possible alternative to cast metal resin-bonded FPDs. These restorations were successfully used as multiple-unit prostheses that employed a variety of abutment tooth preparation designs.

Clinical complications in fixed prosthodontics

The purpose of this article is to identify the incidence of complications and the most common complications associated with single crowns, fixed partial dentures, all-ceramic crowns, resin-bonded prostheses, and posts and cores. A Medline and an extensive hand search were performed on English-language publications covering the last 50 years. The searches focused on publications that contained clinical data regarding success/failure/complications. Within each type of prosthesis, raw data were combined from multiple studies and mean values calculated to determine what trends were noted in the studies. The lowest incidence of clinical complications was associated with all-ceramic crowns (8%). Posts and cores (10%) and conventional single crowns (11%) had comparable clinical complications incidences. Resin-bonded prostheses (26%) and conventional fixed partial dentures (27%) were found to have comparable clinical complications incidences. The 3 most common complications encountered with all-ceramic crowns were crown fracture (7%), loss of retention (2%), and need for endodontic treatment (1%). The 3 most common complications associated with posts and cores were post loosening (5%), root fracture (3%), and caries (2%). With single crowns, the 3 most common complications were need for endodontic treatment (3%), porcelain veneer fracture (3%), and loss of retention (2%). When fixed partial denture studies were reviewed, the 3 most commonly reported complications were caries (18% of abutments), need for endodontic treatment (11% of abutments), and loss of retention (7% of prostheses). The 3 most common complications associated with resin-bonded prostheses were prosthesis debonding (21%), tooth discoloration (18%), and caries (7%).