Osteointegração da hidroxiapatita sintética no processo alveolar da mandíbula de cães

• Autor(a) principal: Duarte, Tatiana Schmitz
• Data de Publicação: 2003
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5195
• topic: Hidroxiapatita; Processo alveolar; Implantes osseointegrados; Hydroxyapatite; Alveolar process; Osteointegrated implant; CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA::CLINICA E CIRURGIA ANIMAL::CLINICA CIRURGICA ANIMAL

The wear of the alveolar process results in the loss of the tooth and its regeneration is required for the use of dental implant. The objective of this project was to evaluate the synthetic hydroxyapatite as bone substitute in the regeneration of the alveolar process. For that, 28 healthy adult dogs, males and females, weighing between 10 and 15 Kg and divided in two groups were used. Defects of approximately 6 x 5 mm were created in the vestibular surface of the alveolar process until reaching the root of the mandibular right fourth premolar. In a group, the defect was totally filled with synthetic hydroxyapatite while in the other it stayed without treatment, being used as control. The animals were submitted to daily clinical evaluations during one week, as well as radiographic exams just after the surgery and on days 8th, 21st, 42nd, 60th, 90th and 120th of postoperative. Bone fragments were collected eight, 15, 21, 42, 60, 90 and 120 days after surgery for the histological analysis under optical microscopy. Most of the animals presented some degree of inflammation, being the recovery slower in the treated group than in the control one. In 100% of the animals there was bleeding stimulus in the presence of hydroxyapatite. The radiographic exams showed growing radiopacity in the animals of control defect group. In the treated defect group there was initially, superior radiopacity when compared to the normal bone, followed by gradual decrease until becoming similar to the neighbor bone, that happened 60 days after the surgery. Microscopically, bone and vasculars tunnels growth was observed inside the hydroxyapatite pores, as well as an intense osteoblast proliferation and neovascularization in the presence of the implant. The hydroxyapatite biocompatibility allowed its integration with the alveolar process through the direct formation of lamelar bone. Therefore, it happens new bone formation as the hydroxyapatite is degraded.