Análise da densidade óssea através da microtomografia computadorizada em calota craniana de coelhos submetidos a enxertia de bio-oss e osso autógeno sob a ação do laser de baixa potência

• Ano de defesa: 2016
• Autor(a) principal: Cenci, Rodrigo Alberto
• Orientador(a): Pagnoncelli, Rogério Miranda
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul
• Programa de Pós-Graduação: Programa de Pós-Graduação em Odontologia
• Departamento: Faculdade de Odontologia
• País: Brasil
• Palavras-chave em Português: LASER (ODONTOLOGIA); TOMOGRAFIA COMPUTADORIZADA; MATERIAIS BIOCOMPATÍVEIS; CIRURGIA BUCOMAXILOFACIAL; ODONTOLOGIA
• Área do conhecimento CNPq: CIENCIAS DA SAUDE::ODONTOLOGIA
• Link de acesso: http://tede2.pucrs.br/tede2/handle/tede/6731

This study is part of a project that aimed to evaluate by means of micro-computed tomography (μCT) image analysis bone density in rabbit calvarial defects treated with low-level laser therapy (LLLT) after filling with blood clot, autogenous bone, and BIO-OSS®. Twenty-nine clinically healthy male New Zealand rabbits weighing 3 to 4 kg each were used in the study. Three bone defects were produced in each rabbit, for a total of 87 defects that were randomly divided into six groups: three experimental groups that received LLLT (EI, EII, and EIII) and three control groups that did not receive LLLT (CI, CII, and CIII). Defect size was 8 mm2 in diameter. The CI and EI defects were filled with blood clot. The CII and EII defects were filled with autogenous bone. The CIII and EIII defects were filled with BIO-OSS®. The experimental groups received LLLT at spot doses of 10 J per session, while the control groups received sham irradiation. Laser irradiation was performed with an aluminum-gallium-arsenide (AlGaAs) laser diode (Thera Lase®) at a wavelength of 830 nm (infrared LLLT was performed every 48 hours after surgery for a total of eight sessions. The animals were euthanized 30 days after surgery, 15 days after the last LLLT session. μCT analyses were conducted using the Skycan 1176 μCT scanner (Skyscan Kontich, Belgium). Samples were analyzed by μCT to identify the percentage bone density compatible with a radiographic image of low, moderate, or high bone density and to evaluate the influence of LLLT on the process of new bone formation. In order to analyze bone density and thus evaluate new bone formation in the surgical site, the region of interest was delimited by drawing a cube (2 mm3) in the central area of the defect and entirely within the region filled with blood clot, autogenous bone, or BIO-OSS®. The results showed that bone density was higher in defects treated with BIO-OSS® in combination with LLLT (group EIII), followed by the nonirradiated BIO-OSS®-grafted group (CIII). In groups where the defects were filled with autogenous bone, bone density was similar for both experimental and control groups. In groups with defects filled with blood clot, bone density was low for both experimental and control groups. We conclude that the combination of BIO-OSS® with LLLT promoted the formation of bone of high radiographic density and that μCT is a reliable technique to measure bone density.