Clinical performance of an innovative self-cure bulk-fill composite compared to dual-cure and light-cure bulk-fill composite in posterior restorations: a 1-year randomized controlled clinical trial

OBJECTIVES: To evaluate and compare the 1-year clinical performance of self-cure, dual-cure, and light-cure bulk-fill composites in class II restorations. MATERIALS AND METHODS: Twenty patients received sixty direct class II restorations, which were divided into three groups (n = 20): Group I: Self-cure bulk-fill (Stela capsules) with Stela primer, Group II: Dual-cure bulk-fill (Fill-Up) with ParaBond adhesive system, Group III: Light-cure bulk-fill (Tetric N-Ceram Bulk Fill) with Tetric N-Bond Universal adhesive. Using the Revised FDI criteria, restorations were assessed after 1 week (baseline) and at 3, 6, 9, and 12 months. FDI scores were compared between groups and across different time points using Friedman and Bonferroni post-hoc tests (P < 0.05). RESULTS: All restorations demonstrated acceptable FDI scores, with a 100% survival rate over 12 months. For all functional and biological criteria, no significant differences were observed among the groups. Esthetic differences were observed where Tetric N-Ceram Bulk Fill demonstrated superior surface luster and texture compared with Stela capsules (P < 0.05), while Fill-Up showed intermediate performance. Stela capsules and Tetric N-Ceram Bulk Fill exhibited the highest color match scores, whereas Fill-Up was significantly lower (P < 0.05). No significant changes were observed over time. CONCLUSIONS: Stela capsules and Fill-Up showed comparable 1-year functional and biological outcomes to Tetric N-Ceram Bulk Fill in class II restorations, while esthetic outcomes were material-dependent. CLINICAL RELEVANCE: Self- and dual-cure bulk fill composites represent reliable alternatives to light-cure bulk fill materials for posterior restorations where esthetics are of lesser concern, offering simplified placement without compromising short-term clinical performance.