Matriz orgânica de osso medular bovino utilizada como alternativa no tratamento das recessões gengivais. Avaliação histológica em cães

Abstract

Biomaterials have been proposed as substitutes for autogenous grafts in gingival recessions treatment. The aim of this study was to evaluate the organic matrix of bovine bone marrow graft in root coating procedure. Three male dogs were used and they re in good general health. On vestibular root at mesial side of second lower pre-molars a bone defect with 3 mm in width and 5mm in height were created. Then, each animal received 2 grafts: conjunctive (autogenous) in the left side and organic matrix of bovine bone marrow (xenogenic) in the right side. After three months, the animals were anesthetized and were removed segments of the alveolar process containing the pre-molars, soft and bone tissue. These segments were fixed in formalin, demineralized and processed for embedding in paraffin. Semi-serial sections were obtained with 5 μm thickness, in vestibular-lingual direction, which were stained with HE and examined under the microscope. In both experimental groups (conjunctive and bone matrix) was observed vestibular crest bone at a lower level and periodont showed normal characteristics, also, in some cases a proliferation of the junctional epithelium in apical direction was noted. The conjunctive presented numerous collagen fibers in various directions, inserted in cementum throughout extension, indicating the formation of a new insertion in the bone defect. The root surface showed areas of external resorption repaired by cellular cementum, including the insertion periodont. In addition, was observed signs of bone resorption of the external board, even with the presence of osteoclasts in activity. The results of this study suggest that the organic matrix of bovine bone marrow allows tissue repair and may be an alternative biomaterial in the treatment of gingival recessions.