PURPOSE：To evaluate the effect of different pretreatment methods on dentin microleakage and bonding effect of caries, so as to provide reference for clinical practice.
Methods: Sixty isolated caries were collected from Department of Oral and Maxillofacial Surgery, Affiliated Stomatological Hospital of Nanchang University from January 2020 to December 2020, and 120 dental samples were obtained by grinding them into two halves along the long axis of the precursor teeth. According to different pretreatment methods, they were divided into group A (2%NaClO), group B (2% chlorhexidine) and group C (75% ethanol). The bond strength, microtensile test and microleakage of the three groups of teeth were compared. SPSS 24.0 software package was used for statistical analysis of the data.
Results: The bond strength of the three groups from high to low was group A, group B and group C(P＜0.05); the fracture type of the three groups was compared, mixed damage of group A was lower than that of group B and group C； microleakage of the three groups was compared, and microleakage of group A was better than that of group B and group C(P＜0.05).
Conclusions: Pre-treatment with 2%NaClO can reduce dentin microleakage and significantly improve the bonding strength of teeth, which is conducive to the promotion and application in the treatment of dental diseases.