Materials and methods
This cross-sectional study was conducted among GDPs and SPs in Saudi Arabia. The former graduated as dentists and had completed at least one-year of an internship. The SPs involved in this study had completed a postgraduate specialist program in prosthodontic and restorative dentistry. Participants also had to be currently engaged as a dental practitioner and/or have a teaching position. Contact details for the enrolled clinicians were obtained from the office of the Saudi Dental Society. Although a sample size of 350 was considered sufficient for statistical analysis, the potential for non-responding participants was anticipated, and the sample size enrolled was 400. Stratified random sampling was performed to select study participants, and GDPs and SPs were considered two distinct strata. The ethics committee of the College of Dentistry Research Centre (King Saud University) approved the study protocol (Ref No. FR 0023). A structured, self-administered questionnaire composed of twenty questions was attached to a study description and a consent for participation form. These packets were either emailed (n=190) or hand delivered (n=210). To maximize the responses obtained, participants were reminded to return their questionnaires three weeks and six weeks after the questionnaires were distributed.
A single investigator analyzed all of the returned questionnaires. Average significance was determined to identify the frequency, pattern, and significance of the response variables identified (e.g., performance factors for RBBs). Using the Statistical Package for Social Sciences (SPSS) version 17 (Chicago, Illinois, USA), Chi-square tests were used to compare the responses of GDPs and SPs for each question in regard to the response options. A p-value less than 0.05 was considered statistically significant.
Of the 400 questionnaires that were distributed, 312 were returned (78% response rate). The response rate for the SPs was 75% (150/200) and for the GDPs it Ro 3306 was 81% (162/200). Both groups had comparable clinical experience (p=0.943) (Table 1). For 60% of the SPs and 71% of the GDPs, RBBs were performed for less than 10% of the available prosthodontic cases. In addition, the majority of SPs (53.33%) considered RBBs as both a permanent and provisional restoration, compared with 43.2% of GDPs who regarded RBBs only as a provisional option (p=0.02). Of the fifteen questions related to RBB performance factors, responses to eight of these questions (53%) were found to significantly differ between the SP and GDP groups.
Regarding design and mechanical factors associated with RBBs (Table 1), more than 75% of both the SPs and GDPs selected fixed–fixed as the most successful RBB design. However, 18.66% of SPs opted for cantilevers, thereby resulting in a significant difference in opinion between the two groups (p=0.04). For 60% of SPs, non-perforated retainers were associated with the clinical success of RBBs. In contrast, 58% of GDPs associated perforated retainers with better RBB performance. However, all of the SPs (100%) and a majority of the GDPs (86.41%) agreed Hydrophilic groups retainer surface treatment improves longevity (p<0.001). The optimum connector height selected by SPs (46.6%) and GDPs (43.2%) was 3mm, followed by 2mm (p=0.04). For optimum retainer thickness, 0.5mm was the most common choice (SPs, 44%; GDPs, 43.2%; p=0.084), followed by 0.7mm (26.66%) according to SPs and 1.0mm (23.45%) according to GDPs. In addition, 30.66% of SPs and 22.22% of GDPs did not consider retainer thickness a factor that influenced RBB longevity. However, for both groups (SPs and GDPs), 61.33% preferred that only one tooth should be replaced by a RBB, while ∼30% favored the use of two pontics (p=0.922). Regarding patient- and technique-related factors (Fig. 1), a majority of the SPs (98.66%) and GDPs (82.71%) accepted that remaining enamel structure influences the performance of RBBs although, 17.28% of the GDPs reported the contrary. In contrast, a greater percentage of GDPs (87.65%) responded that tooth preparation improves RBB performance compared to SPs (78.66%). The anterior maxilla was considered the most favorable location for achieving a successful RBB (SP, 59.13%; GDP, 59.61%), followed by the anterior mandible (SP, 27.95%; GDP, 18.26%). Class I was also the most preferred jaw relation (SP, 50.66%; GDP, 55.55%), although 28.0% of SPs and 17.3% of GDPs believed that occlusal classification does not influence RBB performance. A total of 17.28% of GDPs selected glass ionomer cement (GIC) as their first choice for RBB cementation, while all of the SPs (100%) and a majority of GDPs (82.71%) preferred RBC. However, regarding the principle that RD use improves RBB longevity, 93.33% of SPs agreed and 28.39% of GDPs disagreed (p=0.001).
Materials and methods