A prospective study of cantilever resin-bonded bridges: an initial report

Failure and complication rates of different materials, designs, and bonding techniques of ceramic cantilever resin-bonded fixed dental prostheses for restoring missing anterior teeth: A systematic review and meta-analysis

OBJECTIVES

The objective of this review was to assess clinical trials that have examined the materials, design, and bonding of ceramic cantilevered resin-bonded fixed dental prostheses (RBFDPs) as a potential option for replacing missing anterior teeth. The evaluation primarily focuses on the rate of restoration failure and clinical complications.

MATERIALS AND METHODS

A thorough search of databases including PubMed/MEDLINE, Scopus, and the Cochrane Library, was conducted. The most recent search was performed in October 2023. Clinical studies that compared ceramic cantilevered RBFDPs with double retainers or cantilevered RBFDPs using different ceramic materials or bonding systems were included. The outcome measures considered were restoration failure and complication rates.

RESULTS

Twelve studies met the eligibility criteria. The pooled data showed a statistically significant decrease in complication events when using cantilever designs compared with double retainer designs (p < 0.05); however, there were no differences found between the two designs in terms of restoration failure. The complication and failure rate of cantilever RBFDPs did not show a statistically significant difference with or without ceramic primer application before luting with phosphate monomer-containing luting resin (p > 0.05).

CONCLUSIONS

Ceramic cantilevered RBFDPs have lower complication rates compared with those with double retainers. The use of a ceramic primer prior to luting composite resin for ceramic cantilevered RBFDPs decreases the occurrence of complications and failures, although this effect was not statistically significant. Additional research is required to confirm these findings. Glass ceramic cantilever RBFDPs showed a decrease in success after 6 years, requiring ongoing monitoring, but both zirconia and glass-infiltrated alumina cantilever RBFDPs have demonstrated durability with excellent long-term success and survival rates for up to 10 and 15 years.

CLINICAL SIGNIFICANCE

Cantilever ceramic RBFDPs in the anterior region are a less invasive and valuable treatment option, providing good esthetic results.

Rehabilitation of Congenitally Missing Bilateral Incisors With the Maryland Bridge: A Case Report

Congenital partial hypodontia is a commonly encountered disorder, presenting a challenge for adolescents seeking treatment, as existing options often come with drawbacks. Among these options, the Maryland Bridge stands out for its accessibility and notable benefits in terms of both strength and aesthetics. This article explores the merits of this treatment modality, supported by a detailed case study demonstrating its successful application. An 18-year-old patient was referred to our hospital with a complaint of missing bilateral maxillary incisors. Upon clinical examination, it became apparent that the orthodontic treatment was done and exhibited the absence of bilateral incisors in the upper arch. Subsequent diagnosis confirmed congenital partial hypodontia. To address the missing teeth, a treatment plan centered around the use of a Maryland Bridge was devised. One of the persistent challenges faced by restorative dentists is devising solutions for congenitally missing lateral incisors. Despite the availability of numerous therapeutic alternatives, none are without their limitations. However, the outcome of the rehabilitation in this case proved to be notably aesthetically pleasing, effectively fulfilling the intended purpose. As a result, this article advocates for the Maryland Bridge as a viable option for patients facing similar dental challenges.

Terminology focused on design and retention methods used for anterior resin-bonded fixed partial dentures in English literature: A scoping review

Purpose

Novel terms describing several designs of resin-bonded fixed partial dentures (RBFPDs) continue to appear. Indeed, a variety of terms are used in the English scientific literature The use of a standard terminology is important for a fair and efficient understanding. This study aimed to investigate if the terminology used to describe designs and retention methods for anterior RBFPDs is standard.

Methods

An electronic search in the English literature was conducted in PubMed/Medline to identify all publications reporting RBFPDs in the anterior region until August 2022. This search was completed by hand searching. Terms indicating different designs of RBFPDs were listed and then classified. Percentages of their use were calculated to determine the commonly used terms. Analysis of the use of these terms was performed based on the standards determined by the latest edition of the Glossary of Prosthodontic Terms (GPT). The impacts of the MeSH Thesaurus and GPT on the nomenclature used for RBFPDs was assessed.

Results

A total of 125 articles were eligible for this review. In the retained articles, 86 terms were found. Among them, thirty-nine terms were classified into three groups. Only six terms were defined in the latest edition of GPT (GPT-9). Several classified terms that are commonly used were not identified in the GPT-9. Conversely to the GPT-9 which impact was insignificant, the MeSH Thesaurus had an important impact on the nomenclature used for RBFPDs.

Conclusion

The terminology used to describe designs and retention methods for anterior RBFPDs was non-standard. The GPT-9, constituting an important reference, defined a limited number of terms related to RBFPDs and had no significant impact on the standardization of the terminology used for RBFPDs. Efforts should therefore be continued to standardize the terminology. A specialized mini-glossary grouping and defining all the terms found in this study will helpful in clarifying the terminology used for the anterior RBFPDs.

Do zirconia single-retainer resin-bonded fixed dental prostheses present a viable treatment option for the replacement of missing anterior teeth? A systematic review and meta-analysis

STATEMENT OF PROBLEM

Zirconia has been widely used in restorative dentistry because of its favorable strength and esthetics. However, its polycrystalline structure presents a challenge for resin bonding. Significant research into surface treatments of zirconia to improve bonding has been reported, yet a universally accepted protocol remains elusive.

PURPOSE

The purpose of this systematic review and meta-analysis was to evaluate the performance of anterior single-retainer zirconia resin-bonded fixed dental prostheses (RBFDPs) and review the bonding protocols used in the published data.

MATERIAL AND METHODS

An electronic search of English language literature was conducted in the PubMed and Ovid (MEDLINE) databases. Following the application of inclusion and exclusion criteria, the research was evaluated to assess the quantitative data.

RESULTS

Of the included studies, 1 randomized controlled trial, 3 prospective cohort studies, and 2 retrospective cohort studies reporting on anterior single-retainer zirconia RBFDPs were evaluated. Over a 3- to 10-year period, the success rate of anterior single-retainer zirconia RBFDPs was over 80%. Although there were reports of debonds, this is a minor complication as rebonding is usually possible. Furthermore, catastrophic fractures of the entire prosthesis were rare.

CONCLUSIONS

Evidence for the use of single-retainer zirconia RBFDPs as a suitable treatment option for the replacement of anterior missing teeth is considerable. Based on the findings of this systematic review and meta-analysis, a 2-step process comprising micromechanical retention using airborne-particle abrasion and subsequent resin-zirconia adhesion by the application of 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) can be recommended.

Designing anterior cantilever resin-bonded fixed dental prostheses based on finite element analysis

PURPOSE

A resin-bonded bridge (RBB) is a minimally invasive prosthetic treatment option for intact adjacent teeth. However, it is contentious as to whether the mesial or distal adjacent tooth should be used as an abutment. This study aimed to investigate the potential of finite element analysis (FEA) for the selection of abutment teeth and the determination of the optimal design for anterior cantilever RBBs.

METHODS

Three types of RBBs were designed to simulate loss of the maxillary left lateral incisor. The fixed-fixed RBB (FF-RBB) had one retainer each for the left central incisor and canine. Distal- and mesial-cantilever RBBs (D-CRBB and M-CRBB) had a single retainer on the central incisor and canine, respectively. Three-dimensional models for FEA were generated from computed tomography slices and dental casts. FEA was performed for each RBB to evaluate stresses in the intercuspal, protrusive, and lateral mandibular positions.

RESULTS

The maximum principal stresses on the bridges in the intercuspal position were 141.9 MPa, 93.6 MPa, and 45.7 MPa, for the FF-RBB, D-CRBB, and M-CRBB, respectively. The stress in the D-CRBB position was greater than in the M-CRBB position in the intercuspal, protrusive, and lateral mandibular positions.

CONCLUSIONS

Based on the results, M-CRBB on the canine had a higher clinical performance than D-CRBB on the central incisor. FEA was useful for determining the optimal design of RBB for each patient.

Structural Integrity of Anterior Ceramic Resin-Bonded Fixed Partial Denture: A Finite Element Analysis Study

This study was conducted as a means to evaluate the stress distribution patterns of anterior ceramic resin-bonded fixed partial dentures derived from different materials and numerous connector designs that had various loading conditions imposed onto them through the utilization of the finite element method. A finite element model was established on the basis of the cone beam computed tomography image of a cantilevered resin-bonded fixed partial denture with a central incisor as an abutment and a lateral incisor as a pontic. Sixteen finite element models representing different conditions were simulated with lithium disilicate and zirconia. Connector height, width, and shape were set as the geometric parameters. Static loads of 100 N, 150 N, and 200 N were applied at 45 degrees to the pontic. The maximum equivalent stress values obtained for all finite element models were compared with the ultimate strengths of their materials. Higher load exhibited greater maximum equivalent stress in both materials, regardless of the connector width and shape. Loadings of 200 N and 150 N that were correspondingly simulated on lithium disilicate prostheses of all shapes and dimensions resulted in connector fractures. On the contrary, loadings of 200 N, 150 N, and 100 N with rectangular-shaped connectors correspondingly simulated on zirconia were able to withstand the loads. However, two of the trapezoidal-shaped zirconia connectors were unable to withstand the loads and resulted in fractures. It can be deduced that material type, shape, and connector dimensions concurrently influenced the integrity of the bridge.

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.

A randomised controlled trial of two-unit cantilevered or three-unit fixed-movable resin-bonded fixed partial dentures replacing missing molars

OBJECTIVE

To examine the short-term clinical performance and patient-reported outcomes of two-unit cantilevered (CL2) and three-unit fixed-movable (FM3) RBFPDs for replacement of single molar-sized spans.

MATERIALS AND METHODS

Subjects with an 8-10 mm molar-sized edentulous span(s) and 12 pairs of occluding units were randomly assigned to receive either CL2 or FM3 RBFPD (ratio 1:1). The survival (retention of original prosthesis) and success (survival, complication-free) of RBFPDs at one-year were analysed. Patient-reported outcomes were assessed by prosthesis satisfactory questionnaire and Oral Health Impact Profile (OHIP-49). Data in mean, proportion and longevity were analysed by t-test/Mann-Whitney U test/Wilcoxon signed-rank test, chi-square and log-rank tests respectively at significance level α = 0.05.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT02239718.

RESULTS

Ninety-eight RBFPDs (42 CL2 and 56 FM3) were delivered in eighty-three patients. Majority (n = 89) of the prostheses were provided by operators who have less than 2 years of clinical experience. Sixty-six patients with seventy-eight RBFPDs (35 CL2 and 43 FM3) were reviewed at one-year. One CL2 and one FM3 RBFPDs debonded, resulting in a success rate at 97.1 % and 97.7 % respectively (P > 0.05). Both RBFPDs were rebonded and the survival rate were 100 % for both designs. No significant difference in satisfactions and summary OHIP-49 scores were observed (P > 0.05).

CONCLUSION

CL2 RBFPDs can be used for replacing molar-sized edentulous spans with minimal observable complications up to one-year. Longer-term data is being collected.

CLINICAL SIGNIFICANCE

This clinical trial demonstrates CL2 RBFPDs have comparable clinical and patient-reported outcomes as the FM3 design. This challenges the current dogma in prosthodontics and expands the clinical use of CL2 design which is more conservative, simpler and easier for patients to maintain.

Layer structure and load-bearing properties of fibre reinforced composite beam used in cantilever fixed dental prostheses

This study evaluates the effect of fiber reinforcement quantity and position on fracture load of fixed dental prostheses specimens with different fibre reinforced composite (FRC)/ particulate filler composite (PFC) ratio in a cantilever beam test. Three types of specimen structures where made: Specimens with FRC, PFC, or with a combination of both. Specimen's size was 2.0×2.0×25 mm³ and the thicknesses of the FRC layers were 0, 0.5, 1.0, 1.5 and 2.0 mm. The layers of FRC were placed at the top or at the bottom. Eight groups of specimens were evaluated (n=15/group). The test specimens were statically-loaded until fracture. The fracture loads were linearly dependent on the quantity of the FRC reinforcement when placed at the top (R²=0.941) and bottom (R²=0.896) of the specimens. ANOVA revealed that reinforcement position on the tension side and higher FRC reinforcement volume in the test specimens had positive effect to load bearing capacity (p<0.001).

Resin bonded bridges in patients with hypodontia: Clinical performance over a 7 year observation period

PURPOSE

Resin bonded bridges (RBBs) are considered a conservative option in the management of hypodontia. This study targeted to analyze the survival of resin bonded bridges provided to patients with Hypodontia by staff and students at the Department of Restorative Dentistry, University Dental School and Hospital Cork, Ireland. It was also to determine the factors that may influence the survival of RBBs in patients with hypodontia.

METHODS

Forty patients with hypodontia who received 65 RBBs from 2001 to 2007 were identified and contacted to be recruited for this study. Of these, nine were not contactable, and five failed to attend. Accordingly, 26 patients (65%) participated in the study, with a total of 51 RBBs.

RESULTS

Of the 51 RBBs evaluated, 44 (86%) were still in situ and functional and 7 (14%) failed. The main reason for failure was repeated debonding. The effect of age, gender, the grade of operator and experience, bridge location, design of the bridge, span length and moisture control during cementation, could not be demonstrated.

CONCLUSION

The effect of age, gender, the grade of operator and experience, bridge location, design of the bridge, span length and moister control on RBB survival could not be demonstrated. Majority of patients with hypodontia showed satisfaction with resin bonded bridges. In replacing congenitally missing teeth in patients with hypodontia, resin-bonded bridges would be an acceptable treatment option.

Ten-year clinical evaluation of posterior fixed-movable resin-bonded fixed partial dentures

OBJECTIVES

Two-unit cantilevered resin-bonded fixed partial dentures (RBFPDs) offer long-term retention for anterior and premolar-sized spans. At this center, molar and longer spans have been restored with fixed-movable (FM) RBFPDs to overcome the lower retention rates of fixed-fixed RBFPDs. This retrospective study aimed to evaluate the long-term longevity and the patient-reported outcomes of posterior FM-RBFPDs.

METHODS

Posterior FM-RBFPDs that had been inserted at least five years were reviewed. Survival was "retention of the original prosthesis in mouth" and success was "survival of prosthesis and absence of complications requiring treatment intervention". Prosthesis location, number of units, insertion year, tooth/teeth replaced and operator experience were collected. Patients' acceptance to FM-RBFPDs were assessed using prosthesis satisfaction questionnaire and Oral Health Impact Profile (OHIP-49). Results were analyzed using log-rank and cox-regression tests at significance level α = 0.05.

RESULTS

One-hundred-and-one prostheses were examined. The mean observation time was 126.4 ± 32.2 months. Thirty-six (35.6%) and 63 (62.4%) FM-RBFPDs were rated as success and survival respectively. Prostheses inserted after year 2001 (n = 69) experienced 42.0% (n = 29) success and 75.4% (n = 52) survival, and its survival rate was significantly better than those inserted in or before 2001 (p = 0.01). Five- and ten-year cumulative survival probability of FM-RBFPDs inserted after year 2001 were 82.3% and 74.1% respectively. The most frequent complications were debonding among 34 (33.7%) prostheses. Patients' acceptance were high.

CONCLUSIONS

More recently inserted prostheses showed improved longevity and patients' acceptance to posterior FM-RBFPDs were high.

CLINICAL SIGNIFICANCE

Fix-Movable RBFPDs are a viable tooth replacement option in the posterior region.

Influence of the amount of tooth surface preparation on the shear bond strength of zirconia cantilever single-retainer resin-bonded fixed partial denture

PURPOSE

Conventional resin-bonded fixed partial dentures (RBFPDs) are usually made with a two-retainer design. Unlike conventional RBFPDs, cantilever resin-bonded fixed partial dentures (Cantilever RBFPDs) are, for their part, made with a single-retainer design. The aim of this study was to compare the effect of tooth surface preparation on the bond strength of zirconia cantilever single-retainer RBFPDs. The objective is to evaluate the shear bond strength of these single-retainer RBFPDs bonded on 3 different amount of tooth surface preparation.

MATERIALS AND METHODS

Thirty extracted bovine incisors were categorized to 3 groups (n=10), with different amounts of tooth surface preparations. Teeth were restored with single-retainer RBFPDs with different retainer surfaces: large retainer of 32 mm²; medium retainer of 22 mm²; no retainer and only a proximal connecting box of 12 mm². All RBFPDs were made of zirconia and were bonded using an adhesive system without adhesive capacity. Shear forces were applied to these restorations until debonding.

RESULTS

Mean shear bond strength values for the groups I, II, and II were 2.39±0.53 MPa, 3.13±0.69 MPa, and 5.40±0.96 MPa, respectively. Statistical analyses were performed using a one-way ANOVA test with Bonferroni post-hoc test, at a significance level of 0.001. Failure modes were observed and showed a 100% adhesive fracture.

CONCLUSION

It can be concluded that the preparation of large tooth surface preparation might be irrelevant. For zirconia single-retainer RBFPD, only the preparation of a proximal connecting box seems to be a reliable and minimally invasive approach. The differences are statistically significant.

The Use of All-Ceramic Resin-Bonded Bridges in the Anterior Aesthetic Zone

For several years, all-ceramic resin-bonded bridges (RBBs) have been considered an aesthetic treatment option for the replacement of missing teeth in the anterior region. With continued developments in technology, various different ceramic materials have been used to fabricate all-ceramic RBBs including zirconia, glass-reinforced, alumina-based ceramics, and lithium disilicate glass ceramics. The aim of this article is to provide an overview of all-ceramic RBBs, the advantages and disadvantages associated with these prostheses, as well as to demonstrate their application in replacing missing anterior teeth. Clinical relevance: To present the current literature and clinical application of all-ceramic resin-bonded bridges for replacing missing anterior teeth.

A prospective study of the performance of resin bonded bridgework in patients with hypodontia

Congenital absence of teeth presents a number of clinical challenges in young patients, and little is known about the success rate of restorative dental treatment in these patients. The aim of this study was to conduct a prospective clinical study of the performance of resin bonded bridges in patients with hypodontia.

METHODS

A prospective clinical observation study was undertaken in Cork Dental School and Hospital, Ireland. Forty patients (22 males, 18 females; age range 18-21 years) with a confirmed diagnosis of hypodontia rated as mild (n=26), moderate (n=8) or severe (n=6) participated. Following completion of the orthodontic phase of care, all patients had missing teeth restored with resin bonded bridgework (RBB) using a standardised protocol (48 FF; 17CL design). Patients were followed up for 24 months, with recall visits at 6, 12 and 24 months following provision of RBBs.

RESULTS

65 RBBs were provided, 49 in the maxilla and 16 in the mandible; 43 bridges replaced anterior teeth and 22 replaced posterior teeth. After 24 months, 63 bridges were still in function and deemed to satisfy the preset criteria for success and survival. Two posterior bridges had failed due to repeated debond, and this was attributed to occlusal overload. 20% of the patients demonstrated some evidence of post orthodontic relapse, but this did not require further intervention.

CONCLUSION

In the short to medium term, resin bonded bridgework provides a reliable and minimally invasive solution for replacing missing teeth in patients with hypodontia.

A fixed movable resin-bonded fixed dental prosthesis--A 16 years clinical report

PATIENTS

This report describes the case of a 48-year-old female patient who initially received a 4-unit fixed-fixed (FF) resin-bonded fixed dental prosthesis (RBFDP) for replacement of mandibular left second premolar and first molar. Twenty-one months later, debond of the RBFDP was found at one of retainers. A new fixed-movable RBFDPs with a modified non-rigid connector as well as increased resistance form features was placed and successfully retained at the 16-year clinical review.

DISCUSSION

RBFDPs are a conservative tooth replacement option that requires minimum tooth preparation and retention by a resin cement to etched enamel. However debonding is the most frequently seen complication and has been attributed to the relative movement between abutment teeth during function that stress the bonding interface. This case report highlights the use of modified non-rigid connector which allows relative movement between abutment teeth and therefore a reduced stress on the bonding interface.

CONCLUSION

It is proposed that the use of modified non-rigid connectors that allow independent movement between the abutment teeth during function was responsible for the long term clinical success of fixed-movable RBFDPs.

Three-dimensional finite element analysis of anterior two-unit cantilever resin-bonded fixed dental prostheses

The aim of this study was to evaluate the influence of different framework materials on biomechanical behaviour of anterior two-unit cantilever resin-bonded fixed dental prostheses (RBFDPs). A three-dimensional finite element model of a two-unit cantilever RBFDP replacing a maxillary lateral incisor was created. Five framework materials were evaluated: direct fibre-reinforced composite (FRC-Z250), indirect fibre-reinforced composite (FRC-ES), gold alloy (M), glass ceramic (GC), and zirconia (ZI). Finite element analysis was performed and stress distribution was evaluated. A similar stress pattern, with stress concentrations in the connector area, was observed in RBFDPs for all materials. Maximal principal stress showed a decreasing order: ZI > M > GC > FRC-ES > FRC-Z250. The maximum displacement of RBFDPs was higher for FRC-Z250 and FRC-ES than for M, GC, and ZI. FE analysis depicted differences in location of the maximum stress at the luting cement interface between materials. For FRC-Z250 and FRC-ES, the maximum stress was located in the upper part of the proximal area of the retainer, whereas, for M, GC, and ZI, the maximum stress was located at the cervical outline of the retainer. The present study revealed differences in biomechanical behaviour between all RBFDPs. The general observation was that a RBFDP made of FRC provided a more favourable stress distribution.

A review of the success and failure characteristics of resin-bonded bridges

OBJECTIVES

This literature review was designed to assess and compare the success rates and modes of failure of metal-framed, fibre-reinforced composite and all-ceramic resin-bonded bridges.

MATERIALS AND METHOD

A Medline search (Ovid), supplemented by hand searching, was conducted to identify prospective and retrospective cohort studies on different resin-bonded bridges within the last 16 years. A total of 49 studies met the pre-set inclusion criteria. Success rates of 25 studies on metal-framed, 17 studies on fibre-reinforced composite and 7 studies on all-ceramic resin-bonded bridges were analysed and characteristics of failures were identified.

RESULTS

The analysis of the studies indicated an estimation of annual failure rates per year to be 4.6% (±1.3%, 95% CI) for metal-framed, 4.1% (±2.1%, 95% CI) for fibre-reinforced and 11.7% (±1.8%, 95% CI) for all-ceramic resin-bonded bridges. The most frequent complications were: debonding for metal-framed, resin-bonded bridges (93% of all failures); delamination of the composite veneering material for the fibre-reinforced bridges (41%) and fracture of the framework for the all-ceramic bridges (57%).

CONCLUSIONS

All types of resin-bonded bridges provide an effective short- to medium-term option, with all-ceramic performing least well and having the least favourable mode of failure. The methods of failures were different for different bridges with metal frameworks performing the best over time.

Attitude and awareness of dentist towards resin bonded bridges in Saudi Arabia

STATEMENT OF THE PROBLEM

Resin bonded bridges (RBBs) offer a conservative approach to tooth replacement. However, the use of this treatment option has been limited. Therefore, the aim of this study was to assess the knowledge and attitude of dentists in Saudi Arabia, including general dental practitioners (GDPs) and prosthodontic and restorative specialists (SPs), toward RBBs.

METHODS

In this cross-sectional study, questionnaires designed to survey knowledge of RBB performance factors were distributed to GDPs and SPs (n = 400). Specifically, opinions of GDPs and SPs regarding clinical, mechanical, technique- and patient-dependent performance factors of RBBs were obtained. Average significance and Chi-square tests were used to identify the frequency, pattern, and significance of the response variables identified.

RESULTS

A majority (65.3%) of the subjects reported using RBBs in less than 10% of their prosthodontic cases. The most common reason for the limited clinical application of RBBs was perceived poor retention (23.45%). In addition, SPs regarded the influence of enamel structure, number of pontics, cement type, RBB design, and surface treatment as "very significant" factors with respect to RBB survival. Overall, a statistically significant difference was observed between the responses of GDPs and SPs regarding their knowledge of performance factors for RBBs.

CONCLUSION

In comparison to SPs, GDPs reported greater disagreement with current standards for RBB success factors. Moreover, 60% of SPs and 71% of GDPs used RBBs for less than 10% of their prosthodontic cases. Therefore, continuing education opportunities are needed for practicing dentists, and undergraduate students need to receive greater exposure to the clinical application of RBBs.

Minimally invasive preparation and design of a cantilevered, all-ceramic, resin-bonded, fixed partial denture in the esthetic zone: a case report and descriptive review

Resin-bonded, fixed partial dentures have the potential to offer a minimally invasive, fixed-prosthetic approach to tooth replacement in patients who may not be candidates for implant therapy. However, traditional preparation protocols often recommend extensive preparation designs on two abutment teeth, thereby potentially compromising the long-term health of the adjacent abutments and often resulting in unilateral debonding of one of the retainers in the long term. In light of advances in high-strength ceramic systems capable of being reliably bonded to tooth structure and offering improved esthetic outcomes, as well as clinical and case-series research demonstrating improved survivability of cantilevered resin-bonded fixed partial dentures, new preparation designs and methodologies can be advocated. The following case report demonstrates the clinical application of sonoabrasion, coupled with a dental operating microscope, to minimally prepare a single abutment for a cantilevered, all-ceramic resin-bonded fixed partial denture. Relevant historic and contemporary literature regarding double versus single-retainer resin-bonded fixed partial dentures are reviewed, as well as clinical conditions that are most favorable for such restorations to have an optimal long-term prognosis.

CLINICAL SIGNIFICANCE

If appropriate clinical conditions exist, a cantilevered, all-ceramic, resin-bonded, fixed partial denture may be the most conservative means of tooth replacement in a patient who is not a candidate for an endosseous implant.

Clinical evaluation of conventional cantilever and resin bonded cantilever fixed partial dentures: a comparative study

INTRODUCTION

Ever since the introduction of the minimal preparation fixed partial dentures, the major concern of the clinicians has been its longevity.

AIMS AND OBJECTIVE

The objective of the present study was to compare the clinical performance of resin bonded cantilever bridges with conventional cantilever bridges for a period of 1 year and to evaluate the periodontal changes of abutment teeth using radio visio graphy.

MATERIALS AND METHODS

Fourteen patients with missing first or second premolar were selected for the study. The patients were divided into 2 groups, conventional cantilever group and resin bonded cantilever group.

RESULTS

The results were analyzed using Student's t test and Mann-Whitney U test. The clinical success rate for both the groups was 100%. The amount of bone loss at 6 months for conventional group was 0.11 mm and for resin bonded bridge group was 0.10 mm. The amount of bone loss at 1 year for conventional cantilever group was 0.14 mm and for resin bonded fixed partial denture group was 0.16 mm. There was no statistical difference between both the groups. The results showed that the resin bonded cantilever bridges can be used for the treatment of missing posterior tooth.

The use of zirconium, single-retainer, resin-bonded bridges in adolescents

This paper presents a series of case reports which demonstrate the replacement of the causes of tooth loss which primarily affect children by the use of all-ceramic resin-bonded bridges.

Resin bonded bridges: techniques for success

Resin bonded bridges are a minimally invasive option for replacing missing teeth. Although they were first described over 30 years ago, evidence regarding their longevity remains limited and these restorations have developed an undeserved reputation for failure. This article provides a brief review of the literature regarding bridge success and continues to highlight aspects of case selection, bridge design and clinical procedure which may improve outcome.

In vitro exploration and finite element analysis of failure mechanisms of resin-bonded fixed partial dentures

PURPOSE

The purpose of this study was to explore the debonding mechanisms of two-unit cantilevered and straight and bent three-unit fixed-fixed resin-bonded fixed partial dentures (RBFPDs) and to measure the failure loads needed for debonding.

MATERIALS AND METHODS

Failure load tests were performed using Bondiloy beams simulating both cantilevered and fixed-fixed RBFPDs, luted onto flat-ground buccal surfaces of bovine teeth with RelyX ARC, Panavia F2.0, and UniFix resin cements. The failure loads were recorded, and the debonded surfaces of both the enamel and the restorations were examined for details of interest. Finite element analysis (FEA) was used to calculate the stress concentrations within the cement layers at failure.

RESULTS

Simulated two-unit cantilevered and straight three-unit fixed-fixed RBFPDs showed a significantly higher failure load than the simulated three-unit fixed-fixed RBFPDs with a curved appearance. The FEA models revealed the magnitude and stress locations within the cement layer, resulting in an explanation of the different failure modes.

CONCLUSIONS

The low failure loads for the three-unit bent fixed-fixed RPFPDs, compared with their straight counterparts and the two-unit cantilevered RBFPDs, indicate that clinically a reserved attitude needs to be maintained with regard to three-unit fixed-fixed RBFPDs spanning a clearly curved part of the dental arch. The FEA results make it clear which part of the tooth restoration interface is subject to the highest stress levels, making it possible to design abutment preparations that avoid high interfacial stresses to help prevent debonding.

A retrospective clinical evaluation of two-unit cantilevered resin-bonded fixed partial dentures

BACKGROUND

The authors conducted a study to examine the clinical performance of two-unit cantilevered resin-bonded fixed partial dentures (RBFPDs) that were inserted at The Prince Philip Dental Hospital, University of Hong Kong.

METHODS

The authors recalled patients who had received two-unit cantilevered RBFPDs at least 24 months before the recall examination. The authors recorded the following data: patient's sex and age, operator's experience, prosthesis cementation date, endodontic treatment if performed, bone support, tooth mobility, the presence of shim-stock contacts on the abutment or pontic in intercuspal position, and the presence of aproximal axial contacts adjacent to the prosthesis. They also recorded the date of any debonding with subsequent treatment. They asked the patients qualitative questions about their prostheses.

RESULTS

A total of 269 prostheses were placed in 214 patients and had a mean service life of 51.7 months +/- 19.5 months standard deviation, with a range of 13.2 to 141.6 months. Of 14 failed prostheses, 12 debonded, resulting in a success rate of 94.8 percent and clinical retention rate of 95.5 percent. No discernable rotation or drifting of the abutments was apparent in any of the prostheses. Overall patient satisfaction with RBFPDs was good, with an average assessment score of 8.5.

CONCLUSIONS

The authors observed a 95.5 percent clinical retention rate of 269 two-unit RBFPDs, with no apparent drifting of the abutments. Longer-term follow-up studies are required.

CLINICAL IMPLICATIONS

Two-unit RBFPDs are conservative and clinically retentive prostheses in the short to medium term.

Retrospective survival analysis of 3-unit fixed-fixed and 2-unit cantilevered fixed partial dentures

To evaluate the cumulative survival (CS) rates of fixed partial dentures (FPDs) retained by full-veneer retainers, and those of resin-bonded FPDs provided by graduating dental students for the replacement of a single missing tooth. In 168 patients, 61 3-unit fixed-fixed FPDs and 25 2-unit cantilevered FPDs retained by full-veneer retainers, and 77 3-unit fixed-fixed resin-bonded FPDs and 47 2-unit cantilevered resin-bonded FPDs, were examined for their retention and integrity. The periodontal health, endodontic status and coronal tissues of all abutment teeth were also evaluated. The survival rates of these various designs were analysed with the Kaplan-Meier method. The mean age of all FPDs was 31 months. At 48 months after their insertion, 3-unit FPDs retained by full-veneer retainers had a CS rate of 82%, followed by 2-unit resin-bonded FPDs at 81%, 2-unit FPDs retained by full-veneer retainers at 77%, and 3-unit resin-bonded FPDs at 63%. No significant difference was found between the four designs (P>0.05). Up to both 48 and 60 months, the most common causes of failure were endodontic for FPDs retained by full-veneer retainers, and dislodgement for resin-bonded FPDs. The 3-unit fixed-fixed FPDs retained by full-veneer retainers had the most favourable prognosis after 48 months for replacing a single missing tooth, but the difference between designs was not statistically significant.

Indirect resin-bonded fibre-reinforced composite anterior bridge: A case report

In recent years fibre-reinforced resin composites (FRCs) have gained increasing acceptance in mainstream prosthodontics as viable alternatives to alloy-based restorations. A combination of good aesthetics and fracture toughness validates their use in a diverse range of clinical applications. In this case report an indirect resin-bonded fibre-reinforced composite anterior bridge incorporating a novel design is described. At 24-months recall the prosthesis was problem free and the patient was very happy with the treatment outcome. While definitive long-term data about their clinical performance is scarce, fibre-reinforced resin composite prostheses appear to have a worthwhile role in the conservative treatment of short edentulous spaces.