Investigation of the effectiveness shear bond strength of composite materials to enamel and dentin of primary teeth depending on the technology of modern universal adhesives application

Relevance. The clinical quality of restorations largely depends on the adhesive, which is the main link between composite restoration and the substrate of the hard tissues of the primary tooth. A practicing pediatric dentist will be interested in data on the effectiveness of the bond strength of composite materials with a substrate of hard tissues of primary teeth, depending on the technology of applying modern universal adhesives. Objective. To study the bond strength of composite materials to enamel and dentin of primary teeth using modern universal adhesives with various technologies of applying. Material and methods. The study used samples of enamel and dentin of primary teeth. The shear bond strength (SBS) of the adhesive compound of the composite material, using modern universal adhesives UA No. 1 and UA No. 2 was carried out according to GOST R 51202-98, on a universal test bench equipped with an electronic dynamometer. In the experiment, the main technologies of applying the studied universal adhesives are modeled. The Mann-Whitney U-test was used to verify the validity of differences shear bond strength values in two independent groups. Results. It was found that the 15-second exposure stage of 37% H3PO4 conditioner increases the values of shear bond strength to the enamel of UA No. 1 and UA No. 2 by 51.9% and 72.5%, respectively, but does not significantly affect the values of shear bond strength to the dentine of primary teeth. Conclusion. The most effective technique for applying the studied adhesives, based on the obtained values of shear bond strength to the enamel and dentine of primary teeth, is selective etching of hard tissues