Two-Years Clinical Performance of Bulk-Fill High Viscosity Ormocer Versus Methacrylate-Based Resin Composite Restorative Systems: The Effect of Bulk-Fill Low-viscosity Resin Composite Liners in Class II Restorations.

The study was designed following the Consolidated Standards of Reporting Trials (CONSORT) statement. approvement by the local ethics committee of Mansoura University code register was taken code M 11120520. The patients were selected as they searched for treatment in the Conservative Dentistry Department outpatient clinic, in the Faculty of Dentistry, Mansoura University. A group of 30 patients 21 Females and 9 males was chosen from among 92 participants after careful consideration of the inclusion and exclusion criteria. The sample size estimate was made based on the clinical success rate of posterior class II composite restorations observed in a prior study (97.5% at 24 months). The sample size needed per group was 23 teeth using a significance level of 0.05, power of 80%, and equivalency limit of 15%. A total of 30 patients were chosen, for a total of 120 restorations (30 for each group) after taking potential dropouts into account. To ensure adherence of the participants to the study, all volunteers underwent complete dental treatment and periodic follow-ups. The volunteers were contacted by telephone, WhatsApp message, Facebook, and e-mail for the assessments. Four attempts, including visits to the schools, were made to contact a volunteer before he/she was considered a "loss." both participants and examiners were blind to the interventions. An inter-examiner and intra-examiner agreement of at least 90% was requested before the beginning of the evaluation. Clinical evaluation was performed one week after finishing and polishing (baseline), after 6 months, 12 months, 18 months, and 24 months using the World Dental Federation (FDI) criteria.