This research work presents an analysis of the process of an implant’s osseointegration to the jawbone tissue. The purpose of this work was to describe the processes of assimilation and the biochemical dynamics which occur during dental implantation using implants with different macro-microstructure surfaces at the level of stable free radicals using the electron paramagnetic resonance (EPR) method. The experimental investigation was conducted on seven Vietnamese minipigs over twelve months old and weighing up to 30 kg using implants with various macro-microstructure surfaces (SLA, RBM, and HSTTM) and implantation systems, namely the Adin, Sunran, Biomed, and Osstem systems. The integration of the implant into the bone triggered biochemical processes with the formation of stable free radicals. The EPR method was used to identify the formed paramagnetic species and to study the dynamics of the interaction between the surface of the implant and the bone after one and two months. The concentration of carbonate surface centers increased with the time that the implant was connected to the hard tissue. The “Sunran” and “HSTTM” were established as the most suitable implantation system and surface type, respectively, thanks to the highest rate of osseointegration (assimilation) with the bone (hard) tissue. Thus, the EPR method provides the opportunity to study implantation processes.

Subject. Analysis of the literature confirms that there is a definite relationship between surface microstructure, implant geometry, thread design and primary stability, and osseointegration processes. To date, a sufficient number of works on direct and delayed implantation have accumulated. However, there is not enough convincing clinical data on the quantitative assessment of primary stability at different periods of the osseointegration process. Despite the existence of experimental and clinical observations, it seems impossible to make a definite judgment about the mechanism of such a relationship. This chapter presents clinical studies of the stability and osseointegration of dental implants when performing, according to the indications, in 414 patients of direct and delayed implantation using implant systems with different surface microstructures. Goal. Conduct clinical studies of quantitative indicators of stability and osseointegration of implants with different microstructure of the surface during direct and delayed implantation. Methodology. For the clinical study of primary stability and the process of osseointegration during direct and delayed implantation with immediate functional loading, implant systems with different surface microstructures were used: Alfa Bio, Mis, Astra-Tech, Dentium, Ostem, Antogher, and also Humana Dental with an innovative surface. Osseointegrated implants have been used to achieve a predictable treatment outcome in clinical cases with partial or complete adentia, as well as in the presence of single, included defects. Results. There were no significant differences in stability indicators at the time of implant placement in the alveolar bone, depending on the type of implant and the method of implantation. Conclusions. In the process of integration of the implant into the bone tissue at a later date, the indicators of stability and osseointegration improve. The relationship between the appearance of the implant surface, primary stability and the time of its adaptation was revealed.

This article presents the results of mathematical modeling of the stress-strain state of the finite element analysis of the justification for the use of Humana Dental implants with an innovative surface microstructure and thread design parameters during dental implantation. As a result of the study, after placing the implants in the created three-dimensional model, consisting of trabecular and cortical bones, it was revealed that the angle of implant placement significantly affects the distribution of stress in the bone. The rough, well-structured surface improves the contact of the implant with the bone. The stress distribution on dental implants with different geometry and thread design was revealed, and the most effective thread parameters for uniform load distribution were determined. Aim. Substantiation of the use of Humana Dental implants with innovative macro-microstructure of the surface and thread design parameters during dental implantation in various clinical situations. Material and methods. Samples of BioSink and Vega implants from Humana Dental were studied to assess the stress distribution by mathematical modeling of the stress-strain state in the cortical and spongy bone surrounding two models of implants with a diameter of 4.2 mm and a length of 11.5 mm, as well as with a different thread shape design. The implants were installed in the created three-dimensional model strictly vertically and at an angle of 30°. Geometric models were built in CAD Catia V5, the calculation was carried out in the software package Ansys R19.2. Resalts. As a result of the study, it was revealed that in all cases the maximum concentration of stresses falls on the cortical layer of bone near contact with the implant, and in the spongy bone with vertical installation, maximum stresses in all cases are reached near the lower part of the implant. The peak voltage in the cortical bone was highest in the threaded part of the implants. When changing the angle of installation of the implant, the maximum voltages can increase many times, but when changing the thread pitch, only small fluctuations in voltages are noted, which do not fit into any trend. In the peri-implant region, the cortical bone showed a higher concentration of tension than the spongy bone. Conclusions. The use of finite element analysis made it possible to identify the stress distribution on dental implants with different thread geometries and designs and to determine the most effective thread parameters for uniform load distribution.

Aim. Study by the method of electronic paramagnetic resonance (EPR) physical- chemical and structural features of bone tissue and their effect on the processes of osseointegration during dental implantation using implants with different macro-microstructure of the surface. Material and methods. The experimental study was conducted on 7 Vietnamese visobryu-pig mini-pigs. Under anesthesia, implants with different macro-microstructures of the surface (SLA, RBM, ) were installed under the methods of direct and delayed implantation. At different dates of the experiment, after the appropriate anesthesia, the gentle method was to remove implants with small fragments of periemplant bone tissue. Macro-drugs of bone tissue of the jaws after sawing on blocks and extraction of implants, as well as appropriate preparation, were investigated by the method of stationary electronic paramagnetic resonance. Results. As a result of the study it was revealed that the insertation of the implant into the jaw bone leads to structural changes in the surrounding bone implant. After prior exposure, the EPR spectrums, caused by different types of paramagnetic centers, were observed in the samples studied. Two types of centers, , have been identified. and F is the center. The spectrum of the second type reflects the presence in hydroxiapatites of lattice defects associated with isomorphism, and, . The findings suggest that one of the reasons for the higher content of free radicals (SR) in bone tissue derived from radiation, after dental implantation is the weakening of chemical bonds, greater mobility of fragments that make up its structure. It must be assumed that the high content of SR in the bone in the postoperative period is nothing but a result of the disruption of the mineralization process, which is accompanied by the replacement of phosphate groups with carbonate ions that are free-radicalized. It has also been revealed that the structural integrity of the bone depends to a large extent on the degree of orderliness of microcrystals of hydroxyapatite. According to EPR, the most favorable bone recovery (the process of osseointegration) occurs when using implants with a surface, . Conclusions. EPR research of native and carbonate radicals is a unique tool for studying the physical and chemical and structural features of bone tissue and their role in the process of osseointegration of implants. The speed of osseointegration for implants with different microstructures of the surface varies. EPR can be used as an additional method to control the integration of implants into bone tissue.

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