Idashkina N. The prognosis, prevention and treatment of delayed union of bone tissue in patients with mandibular fractures

The thesis is devoted to the comprehensive study of the problem of delayed union of bone tissue in patients with mandibular fractures. The study of 74 patients with delayed union of mandibular fractures was conducted. The development of delayed union of mandibular fractures correlated with somatic pathology, head injury, polytrauma, substance abuse (p≥95 %). Among the local factors, the first was inflammation in the area of mandibular fractures (p≥95 %). Correlation analysis of clinical and laboratory parameters in patients with delayed union of mandibular fractures allowed to determine a high correlation between β-Cross Laps and osteocalcin (r = -0.70 and r = 0.69, respectively) and BMD, the average reverse correlation relationship existed between the malondialdehyde and catalase activity and BMD (r = -0.57), while these indices had a high correlation with markers of bone remodeling β-Cross Laps (r = 0.80 and r = 0.87 respectively) and for osteocalcin (r = -0.80 and r = -0.84, respectively). There was a high direct correlation between the indices of TNF-α and the indices of LPO, malondialdehyde, catalase (r = 0.75, r = 0.82 and r = 0.87 respectively), and very strong with β-Cross Laps (r = 0.96) and osteocalcin (r = -0.95). Such relationships indicated that secondary immunodeficiency and oxidative stress leading to immuno-structural imbalance and activation of LPO and increased synthesis of proinflammatory cytokines IL-1β and TNF-α are based on the unbalanced bone remodeling processes and the delayed consolidation of bone fractures. Clinical efficacy of treatment complex for patients with delayed union of mandibular fractures and applicability of iPRF, rhBMP-2 injections has been defined. During a clinical study of 57 patients with mandibular fractures confirmed that inflammatory process leads to delayed union, the causative agents of which are atypical aerobic and anaerobic bacteria and their associations with Candida fungi under the conditions of the existing decrease of local immunological reactivity, imbalance in the functioning of the cytokine system and LPO/AOD and imbalance of bone remodeling processes. The effectiveness of photodynamic therapy use for the preventing the development of an infectious-inflammatory process in patients with delayed union of mandibular fractures, which has a pronounced bacteriostatic and local immunomodulatory effect and injections of hyaluronic acid for the correction of oxidative stress has been proven. In the experimental part of the work a computer simulation of mandible with the finite element method was further developed, which was supplemented with the technique of imitation of biological bone and new high-effective methods of mandibular fractures surgical treatment have been developed in unfavorable conditions for reparative osteogenesis.