HISTOLOGICAL AND MORPHOMETRIC STUDIES OF BONE TISSUE AUTOGRAFTS FROM INTRAORAL AND EXTRAORAL DONOR ZONES

Abstract

Major research carried out in modern dentistry and maxillofacial surgery is commonly focused on long-term and stable results for implant rehabilitation of jaw defects and deformities in patients with bone and soft tissue losses at the site of planned implantation. Various osteoplastic materials, donor or the patient’s own bone, tissue-engineering and cellular products are common in clinical medicine, since guided regeneration can help not only recover the volume of bone tissue once lost, yet also ensure an outcome acceptable from both functional and aesthetic view. Guided bone regeneration employs methods of regenerative medicine and tissue engineering, with transplantation of native bone tissue and cell transplants, as well as various osteoplastic materials with osteoinductive and osteoconductive properties. In order to compare the structure of intact bone tissue obtained from intraoral and extraoral donor zones, histological and morphometric studies of bone autografts in 4 certified male cadavers with intact dentition were carried out. The results of histological studies in bone tissue autografts from intraoral and extraoral donor zones revealed that the highest density of bone rods could be observed in biopsies taken from the mandible outer oblique line area and chin symphysis. Whereas the lowest rate of the said factor we observed in the biopsies obtained from the iliac crest area. The highest rate of the inter-rod girder space was found in the area of the iliac crest, and the minimal – in biopsies from the parietal bone. The highest bone vascularization level was identified at the iliac crest and the parietal bone, while its lowest levels were seen in biopsies taken from the area of the mandible outer oblique line. The density of cellular elements was found to be highest at the iliac crest. The lowest density level was registered in biopsies from the area of the mandible outer oblique line. The high rates of cellular elements in autografts from the iliac crest area can be accounted for by the predominance of spongy substance over cortical, while in bone biopsies taken from the mandible outer oblique line, chin symphysis, maxillary tuberosity and parietal bone, the share of cellular elements failed to exceed 27% within the total data set. This points at the predominance of cortical rather than spongy substance. In reconstructive bone plastic surgery for augmentation of the maxillary alveolar process and the mandible alveolar part with significant atrophy, it is reasonable to use autogenous transplants taken from intraoral donor zones. The autogenous transplants have cortical morphology and embryological origin similar to the jaw bones. Bone blocks from the donor zones of the mandible outer oblique line, the chin symphysis and the maxillary tuberosity have the highest density of the bone cortical substance and the duly sufficient amount of spongy substance.