This clinical study aims to evaluate and compare the long-term clinical performance of direct and indirect restorations in Class I cavities of molar teeth over a 10-year period. A total of 54 restorations (27 direct and 27 indirect) were placed in 27 patients, with each patient receiving one direct and one indirect restoration. The restorations were evaluated at baseline, and at 1-, 2-, and 10-year follow-ups using modified USPHS criteria.

This prospective clinical study was designed to evaluate and compare the long-term clinical performance of direct and indirect composite restorations in Class I cavities of permanent molar teeth over a 10-year period.

A total of 27 patients were enrolled in the study. Each participant received one direct and one indirect restoration, resulting in a total of 54 restorations (27 direct and 27 indirect).

Direct restorations were performed intraorally using a microhybrid composite and adhesive system in accordance with the manufacturer's instructions. Indirect restorations were fabricated in the laboratory using a reinforced microfill composite system and cemented using resin cement.

All restorations were clinically evaluated at baseline, and at 1-, 2-, and 10-year follow-up appointments. The modified United States Public Health Service (USPHS) criteria were used for evaluation. The assessed parameters included surface texture, anatomic form, color match, marginal adaptation, cavosurface marginal discoloration, and the presence of caries.

The aim of this study is to provide evidence-based clinical data regarding the durability and performance of direct and indirect composite restorations in posterior teeth.

Inclusion Criteria:

• Patients presenting with two Class I cavities
• Good oral hygiene maintenance
• Absence of pulp or periodontal disease
• Requirement for restoration of permanent molars due to occlusal caries

Exclusion Criteria:

• Presence of parafunctional habits (e.g., bruxism or clenching)
• Poor oral hygiene
• Lack of interest in or refusal to comply with oral hygiene instructions
• Pulp exposure during caries removal
• Percussion sensitivity indicating possible pulpal or periapical pathology
• Spontaneous discomfort associated with periodontal disease