Study on the Effect of Soft-Start Light on Microleakage in Pit and Fissure Closure

To investigate the effect of soft-start light on microleakage and shear adhesion of molars. The healthy third molars extracted from the Department of Stomatology, Zigong First People's Hospital from December 2018 to February 2020 were collected, group A: dyad self-acid fluid resin + strong light mode; Group B: dyad self-acid fluid resin + standard mode; Group C: dyad self-acid fluid resin + soft start mode; Group D: phosphoric acid etching + 3m blocking Agent + strong light mode; Group E: phosphoric acid etching + 3m blocking Agent + standard mode; Group F: phosphoric acid etching + 3m blocking Agent + soft start mode. The microleakage test was performed in simulated oral environment in vitro, and 10 teeth in each group were randomly selected for in vitro evaluation of shear adhesion. A total of 360 teeth, 60 in each group, were included after screening. From Group A to Group F, the scores of microleakage grade decreased in turn, and there was a sig-nificant difference among the groups (p < 0.001), it is suggested that the combination of soft-start light-curing mode, phos-phoric acid etching and blocking agent (Group F) can effectively reduce the grade of microleakage. From Group A to Group F, the shear surface adhesive force showed an increasing trend, and there was a significant difference among the groups (p < 0.001), it is suggested that the combination of soft-start photocuring mode, phosphoric acid etching and blocking agent (Group F) can effectively increase the shear surface adhesion. The soft-start light mode can reduce the micropermeability grade and increase the shear surface adhesion, which may be an effective surgical strategy in the treatment of dental caries.