ABSTRACT
@#In recent years, many researchers have devoted themselves to the application of photodynamic therapy (PDT) in root canal disinfection, as conventional root canal disinfection methods have failed to achieve the optimal effect. Some clinicians have also applied PDT to root canal disinfection. PDT is expected to have a better effect than traditional root canal disinfection. This paper reviews the research progress on the mechanism, effect, influencing factors and limitations of PDT in root canal disinfection. Current research suggests that differences in the type and status of the bacteria, photosensitizers, light sources, operating environment and methods all affect the efficacy of root canal disinfection of PDT. Most of the research into PDT for root canal disinfection finds that it is effective, nontoxic, advantageous to dental pulp regeneration and comfortable for the patient, as well as lacking an excitant; however, its bactericidal effect is inferior to that of sodium hypochlorite. At present, it cannot replace traditional chemical washing but is a promising auxiliary method. The design of the photosensitizer, the energy dose of the light source and the optimal irradiation time need to be determined by further experiments, and more clinical verification is needed before its application in root canal therapy.
ABSTRACT
Objective@#To investigate the effects of leptin on the proliferation of stem cells from human stem cells from the apical papilla (hSCAPs) and the expression of osteogenic/dentinogenic genes in vitro to provide an experimental basis for the sustainable development of young permanent teeth. @* Methods @#The tissue block method was used to isolate and culture hSCAPs from the apical papilla of the immature third permanent molar. The expression of leptin and OBRb in hSCAPs was detected using immunocytofluorescence staining, western blotting and reverse transcription polymerase chain reaction (RT-PCR) analysis. The hSCAPs was treated with 0.1 μg/mL of leptin (0.1 μg/mL group) or 1.5 μg/mL of leptin (1.5 μg/mL group) at different time points. The control group was treated with alpha-MEM medium. Cell proliferation was measured using the CCK8 assay and cell cycle analysis. QRT-PCR was used to detect the expression of related osteoblast/odontogenic genes for alkaline phosphatase (ALP), dentin matrix protein -1 (DMP-1), dentin sialophosphoprotein (DSPP), and osteocalcin (OCN) mRNA. The differences between the treatment groups and the control group were analyzed statistically using one-way ANOVA followed by Bonferroni analysis.@*Results@#The expression of both leptin and OBRb were found in hSCAPs. Compared with the control group, the cell proliferation capacity and S phase cells in the treatment groups were higher than those in the control group, with the 1.5 μg /mL group displaying higher levels than 0.1 μg /mL group, and the treated hSCAPs demonstrated a higher proliferation rate and a higher expression of ALP, DSPP, and DMP-1 from day 3 to day 7, with the 1.5 μg /mL group displaying higher levels than 0.1 μg /mL group , and the difference was statistically significant (P < 0.05), at day 7. The treated hSCAPs demonstrated a lower expression of ALP, DSPP, and DMP-1. Compared with the control group, the treated hSCAPs demonstrated a higher expression of OCN from day 7 to day 14, with significantly higher expression in the 1.5 μg /mL group compared to the 0.1 μg /mL group.@*Conclusion@#Leptin may promote cell proliferation and upregulate the expression of relative osteogenic/dentinogenic genes.