Clinical performance of anterior resin-bonded fixed dental prostheses with different framework designs: A systematic review and meta-analysis

Abstract

Objectives

To systematically review the failure rate and complications of different framework designs of resin-bonded fixed dental prostheses (RBFDPs) in the anterior region.

Methods

A systematic search for clinical studies on RBFDPs published prior to December 2014 in Medline/PubMed, EMBASE, and Cochrane Library databases was conducted and complemented by a manual search. Randomized controlled trials (RCTs) as well as prospective and retrospective cohort studies that compared at least two RBFDP framework designs with a minimum of 2 years follow up were included in this review. The quality of the included studies were assessed using the Newcastle–Ottawa scale for cohort studies and Cochrane Handbook for RCT. Prostheses-based data on reported failure rate/survival rate, debonding, and fractures were analyzed by meta-analysis.

Results

Of 1010 screened articles, one RCT and 4 cohort studies fit the inclusion criteria and were included in the meta-analysis. All included articles have a high risk of bias. Failure rates of single-retainer cantilever RBFDPs were lower than two-retainer fixed–fixed RBFDPs (OR 0.42, 95% CI 0.19–0.94, P = 0.04). Metal-ceramic RBFDPs showed no difference of failure rates between cantilever RBFDPs and two-retainer fixed–fixed RBFDPs (OR 0.93, 95% CI 0.33–2.63, P = 0.89). Debonding was not significantly different between cantilever RBFDPs and two-retainer fixed–fixed RBFDPs (OR 0.61, 95% CI 0.23–1.60, P = 0.32). Metal-ceramic RBFDPs showed no difference of debonding between cantilever RBFDPs and two-retainer fixed–fixed RBFDPs (OR 0.81, 95% CI 0.28–2.34, P = 0.70,).

Conclusions

Within the limitations of the present study, cantilever RBFDPs demonstrate lower clinical failure than two-retainer RBFDPs in the anterior region. The failure of metal-ceramic RBFDPs is independent of the framework design, while the failure of all-ceramic RBFDPs with different designs has not been clear yet.

Clinical significance

Based on the principle of minimally invasive treatment, less number of retainers is recommended for RBFDPs.

Introduction

Since the introduction of resin-bonded fixed dental prostheses (RBFDPs) in the 1970s, this conservative treatment option has become well accepted to replace missing anterior teeth . RBFDPs may provide a promising alternative to dental implants in cases of insufficient bone or other anatomical, medical, or economical limitations . They should also be considered in juveniles when implants are not considered an appropriate option as RBFDPs provide a minimally invasive treatment that can be readily replaced or altered .

According to the dental literature, survival rates of RBFDPs vary widely from 59% to 100% . RBFDPs have shown acceptable survival rates of 87.7% in medium-term observations in a systematic review . Causes for RBFDP failure include debonding , secondary caries on the abutment teeth , and fracture of the retainers , for which debonding is the most common . Therefore, survival of RBFDPs is determined by tooth preparation design, mechanical properties of the prosthetic materials and quality of the adhesive bond .

Anterior RBFDP frameworks are designed with either one (cantilever), two (fixed–fixed), or multiple retainers . The influence of these design options on the clinical performance and survival of anterior PRBFDP’s is controversial. The two-retainer fixed–fixed design has been the most popular and reportedly provides a higher fracture resistance than with a cantilever . In contrast, results of a clinical study demonstrate that two-retainer fixed–fixed RBFDPs have a higher fracture rate than cantilever RBFDPs . A cantilever design has shown significantly better performance than a two-retainer fixed–fixed one in a 10-year clinical study, with survival rates of 94.4% and 67.3%, respectively . The cantilever design appears to be more resistant to debonding caused by occlusal loading and has been recommended as the preferred treatment approach .

The application of minimally invasive and resin-bonded treatment concepts has dramatically increased in recent years. However, the impact of the framework design on clinical performance of RBFDPs has not been sufficiently assessed with an evidence-based approach. Therefore, the purpose of this article was to systematically review the existing literature and assess the evidence as to the influence of different RBFDP framework designs on clinical survival of these restorations.

Materials and methods

A systematic review and meta-analysis were conducted after searching electronic databases (Medline/PubMed, EMBASE, and Cochrane Library) for articles published in English between 1967 and December 2014 based on clinical studies with human subjects only. The MeSH terms and text words included: “ fixed dental prostheses ”, “ resin-bonded bridges ”, “ resin-bonded fixed dental prostheses ”, “ adhesive bridges ”, “ acid-etched bridges ”, “ single-retainer ”, and “ two-retainer ”. A similar search was conducted of the Chinese Biomedical Literature Database (CBM) of the Chinese literature. WHO ICTRP Search Portal (WHO International Clinical Trials Registry Platform Search Portal) for also retrieving ongoing studies. To increase the yield of the relevant studies, references of all full-text articles and related reviews were searched manually.

All the titles and abstracts were screened based on the inclusion and exclusion criteria ( Table 1 ) by two independent reviewers. Subsequently, the full texts were collected after agreement on titles and abstracts, and assessed independently by the same reviewers. Any disagreement was resolved by collegial discussion, or by an independent third reviewer when necessary. Studies meeting inclusion criteria underwent validity assessment. The full texts that did not meet the inclusion criteria were excluded. The process for selecting studies is outlined in Fig. 1 .

Table 1
Inclusion and exclusion criteria.
Inclusion criteria
Type of study Randomized-controlled clinical trials (RCTs)
prospective or retrospective cohort studies; clinical controlled trials (CCT) (when lack of RCTs)
Type of patients (P) Anterior teeth missing patients treated by RBFDPs
Type of interventions (I) Anterior teeth missing patients treated by cantilever RBFDPs
Type of control (C) Anterior teeth missing patients treated by two-retainer fixed–fixed RBFDPs in the same study
Type of outcomes (O) Reporting the details of mechanical or biological complications incidence
Exclusion criteria
Type of study Case reports, case series, animal studies and in-vitro studies
Type of interventions Not including cantilever or fixed–fixed resin-bonded fixed dental prosthesis
Follow-up time Less than 2 years
Outcomes No detailed clinical outcomes but only questionnaire and survey follow-up
Multiple publications on the same patient cohorts

Fig. 1
Results of the article search.

The data provided by the selected studies should contain quantitative outcomes, such as; survival rates/failure rates, debonding, fracture, and other biological complication rates. Two reviewers extracted the complication data rates independently using a purpose designed data collection form. When specific data was unclear or missing, the corresponding author of the relevant publication was contacted via e-mails for further clarification. Survival in this study was defined as the RBFDP prostheses remaining in situ without modification during the observation period. The bias and quality of the included studies were assessed using the Newcastle–Ottawa scale for cohort studies, including patient selection, comparability of groups and ascertainment of outcome . Studies were evaluated on the basis of a star scoring scale with higher scores for higher quality studies . For randomized controlled trials (RCTs), bias assessment was conducted following the Cochrane Handbook for Systematic Reviews of Interventions . Data pooling was subjected to meta-analysis to estimate the odds ratio (OR) and 95% confidence intervals (CI) with a fixed effect model by the Cochrane Collaboration Review Manager (Rev Man, Version 5). Risk estimates of OR and 95% CI were calculated for dichotomous data. The heterogeneity between studies was analyzed using Cochran’s Q test and I 2 . Pre-specified subgroup analysis was evaluated according to the materials used (all-ceramic and metal-ceramic). Statistical analyses were performed with statistical software (Comprehensive Meta Analysis ® version 2.0). Differences were considered statistically significant at the level of 0.05.

Materials and methods

A systematic review and meta-analysis were conducted after searching electronic databases (Medline/PubMed, EMBASE, and Cochrane Library) for articles published in English between 1967 and December 2014 based on clinical studies with human subjects only. The MeSH terms and text words included: “ fixed dental prostheses ”, “ resin-bonded bridges ”, “ resin-bonded fixed dental prostheses ”, “ adhesive bridges ”, “ acid-etched bridges ”, “ single-retainer ”, and “ two-retainer ”. A similar search was conducted of the Chinese Biomedical Literature Database (CBM) of the Chinese literature. WHO ICTRP Search Portal (WHO International Clinical Trials Registry Platform Search Portal) for also retrieving ongoing studies. To increase the yield of the relevant studies, references of all full-text articles and related reviews were searched manually.

All the titles and abstracts were screened based on the inclusion and exclusion criteria ( Table 1 ) by two independent reviewers. Subsequently, the full texts were collected after agreement on titles and abstracts, and assessed independently by the same reviewers. Any disagreement was resolved by collegial discussion, or by an independent third reviewer when necessary. Studies meeting inclusion criteria underwent validity assessment. The full texts that did not meet the inclusion criteria were excluded. The process for selecting studies is outlined in Fig. 1 .

Table 1
Inclusion and exclusion criteria.
Inclusion criteria
Type of study Randomized-controlled clinical trials (RCTs)
prospective or retrospective cohort studies; clinical controlled trials (CCT) (when lack of RCTs)
Type of patients (P) Anterior teeth missing patients treated by RBFDPs
Type of interventions (I) Anterior teeth missing patients treated by cantilever RBFDPs
Type of control (C) Anterior teeth missing patients treated by two-retainer fixed–fixed RBFDPs in the same study
Type of outcomes (O) Reporting the details of mechanical or biological complications incidence
Exclusion criteria
Type of study Case reports, case series, animal studies and in-vitro studies
Type of interventions Not including cantilever or fixed–fixed resin-bonded fixed dental prosthesis
Follow-up time Less than 2 years
Outcomes No detailed clinical outcomes but only questionnaire and survey follow-up
Multiple publications on the same patient cohorts

Fig. 1
Results of the article search.

The data provided by the selected studies should contain quantitative outcomes, such as; survival rates/failure rates, debonding, fracture, and other biological complication rates. Two reviewers extracted the complication data rates independently using a purpose designed data collection form. When specific data was unclear or missing, the corresponding author of the relevant publication was contacted via e-mails for further clarification. Survival in this study was defined as the RBFDP prostheses remaining in situ without modification during the observation period. The bias and quality of the included studies were assessed using the Newcastle–Ottawa scale for cohort studies, including patient selection, comparability of groups and ascertainment of outcome . Studies were evaluated on the basis of a star scoring scale with higher scores for higher quality studies . For randomized controlled trials (RCTs), bias assessment was conducted following the Cochrane Handbook for Systematic Reviews of Interventions . Data pooling was subjected to meta-analysis to estimate the odds ratio (OR) and 95% confidence intervals (CI) with a fixed effect model by the Cochrane Collaboration Review Manager (Rev Man, Version 5). Risk estimates of OR and 95% CI were calculated for dichotomous data. The heterogeneity between studies was analyzed using Cochran’s Q test and I 2 . Pre-specified subgroup analysis was evaluated according to the materials used (all-ceramic and metal-ceramic). Statistical analyses were performed with statistical software (Comprehensive Meta Analysis ® version 2.0). Differences were considered statistically significant at the level of 0.05.

Results

One thousand and ten articles were screened from the electronic search for possible inclusion in the study. A consensus on the studies to be selected was reached after discussion; 969 articles were excluded on the basis of the title and abstract. The reasons for excluding the articles were as follows; either there was a lack of specific data on cantilever or fixed–fixed RBFDPs, they were; case reports, in vitro or non-clinical studies. Full-text articles were obtained for the 41 selected publications. Hand searches were performed on bibliographies of the selected articles as well as of identified narrative reviews. The hand search did not identify any additional articles that matched the inclusion criteria. Thirty-six articles were excluded from the final analysis, resulting in the inclusion of 5 studies. The reasons for exclusion are listed in Table 2 . Only one RCT was included . With the lack of RCTs, clinical controlled trials, prospective and retrospective cohort studies comparing at least two designs of RBFDP were also included into this study and selected for meta-analysis. Two of the 5 included studies were prospective cohort studies and two were retrospective cohort studies ( Table 3 ) . Details of methodological characteristics are summarized in Table 4 .

Table 2
Number of studies excluded with regard to each exclusion criteria.
Exclusion criteria Number of studies
Not reporting designs of resin-bonded fixed partial dentures 24
Multiple publications on the same patient cohort 3
Follow-up time less than 2 years 2
No clinical visit follow-up, only questionnaire and survey follow-up 7

Table 3
Study and patient characteristics of the included studies.
Study Year Study design Mean follow-up time (month) No. of prostheses Age range Drop out
Kern et al. 2011 Prospective cohort study 111 38 Not reported 0
Zhou et al. 2011 Prospective cohort study 41.3 26 >18 0
Garnett et al. 2006 Retrospective cohort study 59.3 71 11 ∼ 43 Not reported
Chai et al. 2005 Retrospective cohort study 47 33 Not reported Not reported
Chan et al. 2000 Randomized controlled trial 34 25 15 ∼ 56 0
Only gold members can continue reading. Log In or Register to continue

Jun 19, 2018 | Posted by in General Dentistry | Comments Off on Clinical performance of anterior resin-bonded fixed dental prostheses with different framework designs: A systematic review and meta-analysis
Premium Wordpress Themes by UFO Themes