The impact of photodynamic therapy in root canal disinfection and smear layer removal using phytocompounds

Aim: The study aims to assess the antibacterial properties of Psidium guajava and Citrus sinensis on Enterococcus faecalis, compare their effectiveness as irrigating solutions, compare their effectiveness with photodynamic therapy (PDT), and evaluate their ability to remove smear layer from the root canal using scanning electron microscopy (SEM). Methods: The study examined the antibacterial efficacy of sweet orange peel and guava leaf extracts on 90 single roots from permanent teeth with closed apices. The roots were stored in a 0.9% saline solution, cleaned, and disinfected. The root canals were prepared using a Protaper rotary file system and irrigated with sodium hypochlorite, ethylenediaminetetraacetic acid, and normal saline. Samples were grouped into two groups – Group I (without PDT) and Group II (with PDT). The samples were irrigated with guava, sweet orange extracts, and 2% chlorhexidine, and the apical third specimen was subjected to SEM to evaluate the smear layer removing ability of the irrigants. Results: The study found that guava extract showed the highest colony-forming unit reduction compared to sweet orange extract. In the experimental Group I without PDT, guava extracts (Group IA) and chlorhexidine (Group IC) were found to remove the maximum smear layer, whereas sweet orange extract (Group IB) did not. Statistical significance was observed between the subgroups. Conclusion: The study found that guava extract maximum smear layer removal from root canal specimens, with or without PDT and chlorhexidine. Sweet orange did not show significant reduction in bacterial count or effectively remove the smear layer. Further research is needed to confirm this.