Retrospective Evaluation of the Clinical Status of Direct Posterior Composite Restorations in Selected Institutions in Nairobi, Kenya

Background: Dental resin composite, a tooth-coloured restorative material, is used to restore carious teeth. With its inception being for aesthetic reasons, the demand from patients, newer materials demand from clinicians and the amalgam phasedown have led to increased placement in load bearing posterior teeth. This study aimed at evaluating the clinical status of direct posterior resin composite restorations placed over a 5-year period in selected institutions in Nairobi, Kenya. Methods: Using 286 posterior resin composite restorations (RCRs) from 95 participants, a cross-sectional study was conducted at a public dental facility; Kenyatta National Hospital Dental Department (KNHDP), a teaching dental clinic; University of Nairobi Dental School (UoNDS), and a private dental facility; University of Nairobi Dental Plaza (UoNDP). Clinical evaluation was done visually using the United States Public Health Survey (USPHS) tool and data was analysed using STATA version 15(College Station TX, USA). Descriptive statistics, Pearson Chi-square and Fischer’s Exact tests were utilized for association between variables. Results: The study respondents were aged between 18- 66 with 50.5% (48/95) of them being male. The RCRs were between 0.25 and 5 years with 36% (103/286) from UoNDP, due to demand of private patients for more tooth-coloured restorations. RCRs in the maxillary arch were 55.6% (159/286) with 71.3% (204/286) being restorations in molars. Mesial-Occlusal/Distal Occlusal (MO/DO) dominated the surfaces restored at 50.7% (145/286) and the least restored surface found to be occlusal-buccal (OB) at 0.7% (2/286). General clinical status of the restorations assessed scored Bravo, followed by Alpha and the least being Charlie. Of the 7 USPHS parameters, Carvo-surface Marginal discolouration and surface texture showed a statistically significant association with the clinical status of the RCRs (p<0.005). Conclusions: The majority of the RCRs in this study had Alpha and Bravo restorations, which are clinically acceptable. Compared to UoNDP and KNHDD, there were more unsuccessful (Charlie) restorations reported at UoNDS. Restorations placed in mandibular teeth showed higher rates of failure than restorations placed in maxillary teeth. Restorations inserted into molar teeth performed better than those inserted into premolar teeth. The performance of occlusal restorations was superior to that of MOD, OB, and MO/DO restorations.