Análise imunoistoquímica e histomorfométrica do reparo de enxertos para levantamento de seios maxilares de coelhos com hidroxiapatita bovina e b-tricálcio fosfato

• Autor(a) principal: Nunes, Leandro Soeiro de Souza
• Data de Publicação: 2009
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USC
• Texto Completo: http://localhost:8080/tede/handle/tede/98
• topic: HIDROXIAPATITA BOVINA; b-TRICÁLCIO FOSFATO; REPARO ÓSSEO; LEVANTAMENTO DE SEIO MAXILAR; COELHO; IMUNOISTOQUÍMICA; BOVINE HIDROXYAPATITE; b-TRICALCIUM PHOSPHATE; BONE REPAIR; SINUS LIFT; RABBIT; IMUNOHISTOCHEMISTRY; ODONTOLOGIA::CIRURGIA BUCO-MAXILO-FACIAL

Several biomaterials are available and indicated for sinus lift procedures associated or not with autogenous bone, presenting different biological behaviors due to their origin, shape, size, and level of degradation. Objective: The aim of the present study was to analyze and compare the autogenous bone with two biomaterials: bovine hydroxyapatite (HA) (Bio-Oss ) and β-tricalcium phosphate (β-TCP) (Cerasorb ) in sinus lift procedures. Methods: Male rabbits underwent bilateral sinus lift procedures under general anesthesia and randomly divided into three groups, with eight animals each, as follow: Group 1 (control): particulate autogenous bone; Group 2) bovine HA; and Group 3) β-TCP, to be killed after one, two, four and eight weeks. Results: The microscopic analysis showed similar repair pattern and satisfactory tissue response between test groups (2 and 3), and clear osteoconductive capacity of both materials. New bone formation, soft and medular tissue, remain material or particulate bone graft area were obtained by histomorphometric analysis and submitted to ANOVA and Tukey tests (p < 0,05). After two weeks, significant statistical differences in new bone formation were found between Group 1 (27,76 ± 7,8) and Groups 2 (14,22 ± 3,23) and 3 (11,1 ± 7,74) and in relation to remain material between the same groups, Group 1 (16,72 ± 14,9) and Groups 2 (60,55 ± 6,28) and 3 (46,96 ± 10,01). After four weeks, significant statistical differences were detected in bone formation between Group 1 (60,71 ± 8,5) and 2 (14,13 ± 3,2) and between Group 1 (60,71 ± 8,5) and 3 (18,05 ± 1,4). The last period showed differences in bone formation between Group 1 (54,19 ± 11,4), and Groups 2 (47 ± 12,1) and 3 (27,33 ± 8,7) and between Groups 2 (10,52 ± 2,2) and 3 (40,62 ± 8,4) in relation to soft tissue. In Group 1, moderate imunohistochemical expression for Cbfa-1 was observed, mainly in cells of granulation tissue after one and two weeks of bone repair, becoming weak in periods of four and eight weeks. However, Group 2 presented a more intense expression after one and two weeks, also with a tendency to decrease in the last periods of bone repair. Weak imunohistochemical expression was noted in Group 3, in all established periods of the experiment. In relation to VEGF the imunohistochemical expression was seen in the endothelial cells of new formed capillaries, with no differences between the experimental groups in all analyzed periods. In conclusion, both materials permitted bone growth in an osteoconductive pattern, with no interference in bone remodeling in the last period, showing a slight improve in bone tissue formation when using HA, confirmed by imunohistochemistry.