Effect of photodynamic therapy with natural photosensitizers on microleakage of class V composite restorations in primary teeth.

This study aimed to investigate the impact of photodynamic therapy (PDT) using natural photosensitizers-curcumin, riboflavin, and phycocyanin-on microleakage in Class V restorations of primary teeth, clarifying the comparative effectiveness of each compound. This in vitro study was conducted on 76 extracted primary molars with sound buccal and lingual surfaces, randomly divided into four groups (n = 19). Class V cavities were prepared and treated with either no photosensitizer (control) or PDT inclding curcumin, riboflavin, or phycocyanin. The photosensitizers were applied using a syringe passively for 5 min and underwent laser irradiation (Wiser 3, DoctorSmile, Italy) blue laser with 450 nm wavelength for curcumin and riboflavin, and red laser with 635 nm wavelength for phycoyanin, both with 500 mW power for 30 s). The cavities were subsequently rinsed, and air-dried before restoration placement. The teeth restored by composite resine.After Thermocycling, dye penetration was assessed under a microscope. Two blinded examiners evaluated leakage, and reliability was assessed with Cohen's kappa. Kruskal-Wallis and Mann-Whitney. U tests with Bonferroni correction were used. No significant difference was in cervical microleakage (P = 0.13). PDT groups showed significantly lower coronal microleakage than control (P < 0.05). aPDT using natural photosensitizers reduced coronal microleakage in Class V composite restorations in primary teeth.