Uso de enxerto autógeno não vascularizado associado à Oxigenoterapia Hiperbárica nas reconstruções mandibulares

Abstract

Reconstruction of mandibular defects caused by tumor resection is a challenge for the maxillofacial surgeon. The size of the bone defect, the type of graft used (vascularized or non-vascularized), the soft tissue conditions of the recipient area, are factors that directly influence the success of the treatment. The use of vascularized bone grafts presents a good prognosis for the treatment of large mandibular defects; however, they present some difficulties, since it requires a team of microvascular surgery, longer hospitalization time and high costs. An alternative is the use of nonvascularized grafts such as those of iliac crest, however, due to the lack of vascularization, neoangiogenesis is sometimes difficult, and may result in reduction of the incorporated graft volume or even in the non-union of the grafts. Several studies have reported the effects of neoangiogenesis and neo-osteogenesis using Hyperbaric Oxigen Therapy (HBO). Hyperbaric oxygen therapy consists of administering pure oxygen at an atmospheric pressure of 2.5 ATA (absolute atmosphere). The patient is placed in a camera where they breathe pure oxygen for a period of 90 minutes. The objective of this research is to evaluate the effects of hyperbaric oxygen therapy on autogenous bone grafts used for mandibular reconstruction in patients affected by bone neoplasms, through computerized microtomographies and histologic analysis of biopsies from each patient. This study was divided into four specific objectives; Specific objective 1: To evaluate the effects of hyperbaric oxygen therapy on the remodeling of autogenous bone grafts obtained from iliac crest and used for the reconstruction of extensive mandibular defects of patients submitted to resection, through computerized microtomography, immunohistochemistry and histologic analysis of Trephined bone tissue; Specific objective 2: The objective of this study was to describe a series of cases of patients submitted to the installation of implants in provisional immediate load in mandible reconstructed with iliac crest grafts, discussing the clinical aspects and the feasibility to apply this type of treatment; Specific objective 3: The objective of this study was to describe a treatment protocol for patients with odontogenic tumors undergoing mandibulectomy and subsequent mandibular reconstruction with nonvascularized iliac crest grafting associated with hyperbaric oxygen therapy; Specific objective 4: The objective of this study was to report a clinical case with a mandibular tumor submitted to bone resection, mandibular reconstruction using free iliac crest grafting associated with hyperbaric oxygen therapy, followed by the installation of implants with immediate loading.