Biomimetic strategy of a hybrid biointerface creation between native human dental tissue and dental composite

Abstract

The aim of the studyis the peculiarities of the molecular composition of the biointerface between the native human dental tissue and the dental composite, created in an alkaline environment, based on synchrotron chemical infrared micro-mapping. When creating a biomimetic interface under alkaline conditions, we used an original bioprimer, dentin conditioner, nanofilled universal adhesive, and a light-curing compomer based on BIS-GMA. Biointerface analysis was carried out on the basis of chemical infrared micro-mapping, implemented using the equipment of the Australian Synchrotron, and subsequent multivariate cluster analysis of the collected spectral data array. It was shown that the use of a primer modified with a set of polar amino acids additionally facilitated the opening of dentinal tubules and the penetration of the bioprimer components into the dentin with the formation of a deeper transitional hybrid layer. At the same time, modification of the Bis-GMA adhesive using nanocrystalline carbonate-substituted hydroxyapatite, which has a structural and morphological organization similar to natural dental tissue apatite, led to an increase in the degree of conversion of the used adhesive material during polymerization. Using a biomimetic strategy and nanocrystals of carbonate-substituted hydroxyapatite as a filler of a universal adhesive, the necessary conjugation at the interface with dentin can be achieved without disrupting the polymerization processes, as well as preserving the natural structural complexity of the intact tissue, which makes it possible to take into account the individual characteristics of the patient.