Determination of the synthetic hydroxyapatite life circle used in dental practice

Abstract

Dental materials are developed as general materials for specific aplication in oral environment. To determine the functional properties of these materials, nonstandard approach and specific methods need to be utilized. In this study, two methodologies of material testing were used - artificial aging and quantification of visual informations for life circle assesment of hydroxyapatite (Hap) based materials. Hap was chemically synthetized, resulting in high purity and crystallinity of the material. Artificially produced Hap is used in stomatology for repair of bone tissue, as a filling for periodontal defects, and as a preservative augmentation for alveolar ridges. These materials are also used for definitive root canal obturation in endodontic therapy procedure as an apical plug or as complete filling material. This research study was focused on the analysis of the bonding properties of Hap-based materiales to the root canal walls. The methodology of artificial aging was used together with the quantification of visual informations for the purpose of quantifying the Hap bonding properties and bonding quality. Experiments were done in vitro, with the artificial saliva as the agressive agent. The experimental teeth were analysed by a high resolution optical microscope for the morphological characterisation of the bonding layer. A model for the bond life circle assesment was developed. Hap-based materials showed favorable properties for dental use. The presented results proved that the combination of the two methodologies (artificial aging and quantification of visual informations) could be used as a tool for analysing the material-dentine interaction.