Clinical performance of Class II resin composite restorations in primary molars with or without pulpotomy: a prospective 24-month clinical study

PURPOSE: To evaluate the clinical performance of Class II resin composite restorations in primary molars following pulpotomy and to compare them with Class II composite restorations in non-pulpotomised primary molars over 24 months. METHODS: This prospective within-patient controlled study included healthy children aged 4-8 years with at least one primary molar requiring a Class II resin composite restoration with pulpotomy and one without pulpotomy. Restorations were placed under rubber dam isolation using a fifth-generation adhesive and resin composite. NeoMTA® was used for pulpotomies. Clinical evaluation was performed at 12 and 24 months by a blinded examiner using modified 'USPHS criteria'. Cross-sectional comparisons were performed using Chi-square or Fisher's exact tests, whilst longitudinal changes were analysed using the McNemar-Bowker test (p < 0.05). RESULTS: Forty children (80 teeth) were enrolled initially. At 12 months, 37 children (74 teeth) were evaluated, whilst 32 children (64 teeth) completed the 24-month recall. Most restorations in both groups remained clinically acceptable throughout the study period. Marginal integrity was significantly lower in pulpotomised teeth at 12 months (p = 0.003) and at 24 months (p = 0.011). No statistically significant differences were observed for marginal discoloration, surface texture, wear, postoperative sensitivity, or recurrent caries (p > 0.05). Longitudinal analysis demonstrated significant deterioration in marginal integrity over time in the pulpotomy group (p = 0.041). CONCLUSIONS: Resin composite restorations in primary molars showed acceptable performance in both groups. However, restorations in pulpotomised teeth demonstrated reduced marginal integrity after 24 months.