RESUMO
Introduction: Microbial agents play a crucial role in periapical lesions and despite mechanical preparation, presence of persistent bacteria in root canal system is a challenge. Photodynamic therapy offers a debridement method, utilizing photosensitizers such as Curcumin, Indocyanine Green (ICG), and Methylene Blue (MB). This study aimed to assess and compare the penetration depth of these photosensitizers on the lateral surface of the root canal. Materials and Methods: The crown of 30 single-rooted teeth were separated by a diamond disc. The canals were prepared using a rotary system and were rinsed with 10 mL of 2.5% NaOCl. In order to remove the smear layer debris, 17% EDTA was placed in the root canal for 1 min, then rinsed with NaOCl and saline. The teeth were sterilized by autoclave and randomly assigned to three groups that filled with curcumin, ICG, or MB. Subsequently, they were incubated for 10 min and dried up by paper. Longitudinal sections were cut, and penetration depth of the photosensitizers in coronal, middle, and apical sections were measured using a stereomicroscope. Results: Curcumin demonstrated a higher average penetration depth (3000 µm) than MB, and MB showed higher penetration depth than ICG. Significantly different penetration depths were observed in pairwise comparisons among all three groups (P<0.005). Conclusion: Curcumin with its superior average penetration depth, emerges as a promising choice for effective root canal disinfection in endodontic treatments. Consideration of these findings may enhance the selection of photosensitizers in clinical applications.
RESUMO
Statement of the Problem: Candida albicans (C. albicans) is recognized as the most common opportunistic pathogen in patients with an impaired immune system, and due to the frequent use of antifungal medicine, a variety of drug-resistant species are developing. Probiotics are a part of the human microbiome and natural competitors of Candida by producing lactic acid, low pH, and other secreted metabolites. The role of probiotics in preventing fungal infections has always been discussed. Purpose: This study aimed to investigate the antifungal effect of Lactobacillus casei (L. casei) on fluconazole- and amphotericin B-resistant C. albicans species isolated from the oral cavity of acute myeloid leukemia patients. Materials and Method: In this experimental study, eight strains of fluconazole- and amphotericin B-resistant C. albicans were used. The antifungal effects of probiotic L. casei and nystatin were measured by the co-aggregation method 1, 2, and 4 h after beginning the study. After each hour of exposure, C. albicans and L. casei colonies were counted. Results: L. casei had a significant ability to aggregate with both fluconazole- and amphotericin B-resistant C. albicans in all designated intervals, which increased with time. In the first hour of the study, no significant difference was observed between the effects of L. casei on the two drug-resistant strains. However, as time passed, it had a more significant antifungal effect on fluconazole, compared to amphotericin B resistant species (p Value<0.001). Cell counts showed that the number of fungal cells decreased significantly as time passed (p< 0.001). Conclusion: L. casei had a significant ability to aggregate with both drug-resistant C. albicans species and showed higher antifungal activity on fluconazole-resistant than amphotericin B-resistant species.
