Purpose: To evaluate the clinical effectiveness of indirect composite restorations in permanent molars with excessive substance loss in pediatric patients who have undergone root canal treatments. Materials and Methods: Molars of 29 pediatric patients underwent endodontic treatment. Sixteen molars were restored with an indirect posterior composite resin restoration and 13 molars were restored with a direct posterior composite resin restoration. The success of the restorations was evaluated for 2 years based on United States Public Health Service (USPHS) criteria, photographs after staining with basic fuchsine, and radiographic data. Data obtained from both groups were compared using the Mann-Whitney U-test and Wilcoxon signed rank test. Results: Evaluation of the clinical and radiographic data revealed no observable, statistically significant differences between the posterior and the indirect posterior composites (p > 0.05). However, evaluation of photos taken of the patients' molars after staining with basic fuchsin revealed that direct posterior composites showed increased staining on the margins of the restorations after six months (p 0.05). Conclusion: Considering the difficulties of restoring endodontically treated permanent teeth with excessive substance loss in child patients, indirect restorations may be seen as a better option. Keywords: indirect posterior composite, inlay, direct posterior composite, root canal treatment