Shumynskyi Y. Clinical, anatomical and biomechanical substantiation of maxillary fractures surgical treatment methods

The dissertation presents a scientific substantiation and practical solution of one of the actual problems of maxillofacial surgery: increasing the efficiency of maxillary reconstruction in its traumatic fractures by developing the concept of their surgical treatment using computer modeling algorithms and improved methods of functionally stable osteosynthesis, depending on features of the anatomical structure of the damaged bone. According to the literary data, traumatic injuries of the mid-facial bones account for up to 70 % of all fractures of the facial skull in patients with combined cranio-maxillofacial trauma and polytrauma. Scientists explain significant difficulties in the treatment of patients in this category, high frequency of postoperative complications and unsatisfactory results with the features of the topographic anatomy and architecture of the mid-facial bones. It is known that the maxilla is an integral part of a single anatomical and functional complex of immobile bones of the facial skull, along with the zygomatic, naso-ethmoid-orbital complexes, nasal septum, orbital bones, palatine bone. The unique anatomical structure of mid-facial bones provides perception and redistribution of masticatory loading, support and fixing of the upper teeth in the correct occlusal position, they also provide a support for masticatory muscles and muscles of a soft palate, creating conditions for mastication, swallowing and speech, participate in the formation of orbits, nasal cavity, sinuses and subtemporal fossa, and perform a protective function as well.This is realized mostly due to the thickening of the compact bone layer with the specific orientation of the ostheons in the most loaded areas - buttresses. In case of injury, the system of buttresses is destroyed by a complex mechanism that is not fully understood. Factors influencing the nature of mid-face bones destruction are external forces different in nature, speed, magnitude, direction and area of application, as well as peculiarities of the anatomical structure of mid-facial bones, especially the degree of pneumatization, which determines the relationship between the volume of air cavities and bone structures. The present study aimed at the analysis of topographic characteristics of maxillary fractures depending on anatomical structure and architecture of the mid-facial bones, definition of biomechanically - unfavorable types of maxillary fractures, substantiation of methods for surgical treatment with the use of autologous bone grafts for restoration of integrity of the vertical buttresses in the mid-facial area. The research program consisted of four stages with their sequential implementation, followed by generalization from the standpoint based on a systemic approach.