Clinical Comparison of Incremental Layering Technique and Bulk-Fill Technique in Posterior Composite Restorations

Abstract

Background: Direct resin composite is always the preferred material for posterior tooth restoration, and can be placed in either the traditional incremental layering technique or the newer bulk-fill technique.

Objective: To clinically evaluate and compare the incremental layering method and the bulk-fill method regarding their postoperative sensitivity, marginal adaptation, and restoration success in posterior composite restorations.

Materials and Methods: Randomized clinical trial conducted at the Department of Operative Dentistry, Islamic International Dental Hospital Islamabad, Pakistan, for a period of 9 months from September 2025 to May 2026. A total of 120 posterior teeth were selected and randomly divided into two groups (n = 60), one group (Group A) restored with an incremental layering technique and the other group (Group B) restored with the bulk-fill technique. Data was analyzed using SPSS (version 25), and a p-value of <0.05.

Results: Sensitivity at 1 week was significantly lower in the bulk-fill group than in the incremental group (8.3% vs 18.3%, p=0.041), but this difference was smaller at 1 month and 6 months. At 6 months, there was no difference between the two groups in terms of marginal adaptation or marginal discoloration (p>0.05), and the overall clinical success rate at 6 months was 96.7% for bulk-fill and 95.0% for incremental restorations (p=0.65).

Conclusion: The bulk-fill technique resulted in significantly less early postoperative sensitivity than the incremental layering technique, with marginal adaptation and short-term clinical success being similar for the two techniques.