Incidence of Caries and Periodontal Disease in Abutment Versus Non-Abutment Teeth Among Removable Partial Dental Prosthesis Wearers: A Systematic Review Utilizing Synthesis without Meta-Analysis

This review compared the incidence of caries and periodontal parameters of disease activity in abutment versus non-abutment teeth in removable partial dental prosthesis (RPDP) wearers. Two reviewers independently searched five electronic databases (PubMed, EBSCO-CINAHL Complete, EBSCO-Dentistry and Oral Sciences, Wiley Cochrane Library, and Scopus) to retrieve studies published until September 9, 2023, and selected randomized controlled trials (RCTs) and longitudinal studies (LSs) reporting at least three months of recall post-delivery. Frequency of new and recurrent caries, probing depths (PPD) in millimeters, and sites with bleeding on probing (BoP) were recorded. Among the 11,260 records identified, 21 reports from 20 studies (two RCTs and 18 LSs) were included. Four reports described PPD with BoP, 16 reported caries incidence, and one reported both. Synthesis without meta-analysis guidelines were followed for data analysis. Relatively stable periodontal health with 3-month to 10-year follow-up was observed. Caries incidence ranged from 11.9%-46.96% over 2-5 years. Six of the eight reports showed higher caries incidence in abutments than in controls. Cochrane risk of bias (RoB-2.0) assessment indicated high risk in one RCT and moderate risk in another. Four LSs were rated 'good' per the Newcastle-Ottawa Scale with Agency for Healthcare Research and Quality standards. Certainty of evidence was evaluated with Grading of Recommendations Assessment, Development, and Evaluation. Increased BoP at recalls of 3 months to 7 years was observed. Weak evidence supported stable PPD in RPDP patients. Increased caries risk in abutments compared to non-abutments suggested a need for regular follow-ups.