REPARATIVE PROCESSES PROMOTION IN SPORT INJURIES WlTH BONE LESIONS

Abstract

INTRODUCTION- The injuries of bones in maxillofacial region as a result of traumas in sport are not uncommon. Implantation of apatites containing glasscristalmaterials (AGM) in granules has been suggested for promotion of reparative processes and rehabilitation of athletes with bone defects. The aim of the work is comparative study of osteoinductive characteristics of AGM and composite material based on collagen sponge with 80% AGM (CSAGM)."Biositallw (Russia) has been used as AGM, and "Biositacol" (Russia) - as a CSAGM. The experiment was made on 18 rabbits (3 groups). In 1' and 2nd groups the material have been implanted into perforated holes with diameter 2 mni and 5 mm in depth, located in mandible along the alveolar ridge between incisors and posterior teeth. One group was used as a control one (perforated hole has been filled with blood clots).The samples of implanted materials were taken in 3,7 day, 2,4,6,8 weeks after implantation. Osteoinductive characteristics have been investigated by histomorphologic technique according to osteoblast formation rate and site, their maturation into osteocytes which further formed bone trabeculas with bone plates construction. RESULTS-In the control group of animals whose mandible perforations had been allowed to fill with blood clots, histologic examinations showed acute inflammation reactions in the periphery of the bone defects after seven days. After 2-4 weeks the reproduction of fibroblasts and formation of conjuctive tissue in the bone defect were observed. By the sixth week, the jaw bone defect was filled in with well formed mature conjunctive tissue, and by the eighth week isolated bone tissue growths were observed. In the early stage of the experiment, 3-7 days after implantation, acute inflammation with lymphohisteocytic reaction around the AGM granules was recorded. At the same time, by the second week muttinucleated cells of foreign bodies appeared in all test groups. By the forth week, tymphohisteocytic infiltrates disappeared, and the multinucleated cells of foreign bodies had appeared to resolve the AGM granules. Surrounding the AGM granules, a great number of osteocytes had formed young conjunctive tissue which incapsuled almost every granule. By the sixth week, the histological preparations showed the formation of bone tissue in the periphery of the defect. Regenerated bone spicules in the process of mending developed the spongy structure of bone tissue. By the eighth week, the process of osteogenesis around the AGM granules was far advanced everywhere. During the implantation of CSAGM the extensive osteoclastic response at the defect borders was defined by the 3d day. From the 7Ih day to two weeks single osteoblasts appeared and proliferation of immature cells of collagen tissue was noted. By the second week fibroblast net between AGM granules as well as single new-formed collagen fibers and single bone trabeculas at the defect borders appear. During the 4'h week the defect periphery was filled with bone trabeculas with their partial growth towards the centre. By the 6Ih week osteogenesis was marked all over the defect. CONCLUSION-Both AGM and CSAGM implantation promotes reparative processes in bone injuries comparing with the control group. In CSAGM implantation histomorphological pattern of bone tissue elements formation appears in two weeks earlier than in AGM implantation. The difference in direction of reparative processes in bone has been noted: all over the defect in the zone of AGM implantation and at the defect borders in CSAGM implantation.