Determination of the synthetic hydroxyapatite life circle used in dental practice

Dental materials are specific materials that were developed as a general materials for specific aplication in oral environment. To determinate the functional properties of this materials, we are obligated to use nonstandard approach and specific methods. In this study, two methodologies of material testing-artificial agging and quantification of visual informations for life circle assessment of hydroxyapatite (Hap) based materials, were used. Hap was chemically synthetized which produced the material with high purity and crystallinity. 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. In the mean time those materials are used for definitive root canal obturation in endodontic therapy procedure as an apical plug or as complete filling material. This research was focused on the analysis of the bonding properties of the Hap based materials to the root canal walls. The methodology of artificial agging was used together with the quantification of visual informations in purpose to quantify the Hap bonding properties and bonding quality. Experiments were done in-vitro, with the artificia saliva as the agressive agent. The experimental tooths were analyzed by the high resolution optical microscope for the morphological characterisation of the bonding layer. The model for the bond life circle assessment was developed. Hap based materials proved that has favorable properties for the dental use. The presented results proved that the combination of two methodologies (artificial agging and quantification of visual informations could be used as the tool for analyzing the material-dentine interaction.