Avaliação da alteração do perfil de colágeno de dentes extraídos de pacientes submetidos a radioterapia de cabeça e pescoço

• Ano de defesa: 2016
• Autor(a) principal: Benevides, Breno Souza
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Radioterapia; Neoplasias de Cabeça e Pescoço; Colágeno Tipo I; Colágeno Tipo III; Dentina; Ligamento Periodontal; Cárie Dentária
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/18060

Compromised dental health by incidence of radiation is taken as a result of the reduction in salivary flow as well as possible direct radiogenic damage to tooth structure. The exact nature of the latter remains to be elucidated. The aim of this paper is to investigate the anatomical predominance of collagen type I and type III in the dentin and periodontal ligament and the amount of these collagens in the periodontal ligament of extracted teeth within the radiation fields of patients who have underwent radiotherapy (RT) for treatment of malignant head and neck tumors. The sample consisted of 20 teeth, 8 carious teeth of patients who underwent total dose of less radiation than 60 Gy (experimental group I - EG I), 6 carious teeth of patients who underwent total radiation dose equal to or greater than 60 Gy (experimental group II - EG II) and 6 healthy erupted teeth not subjected to radiation (control group - CG). A histomorphometrical study was conducted using the staining technique Picrosirius Red with polarized light. Qualitative analysis of dentin noticed the predominance of type III collagen in the surrounding regions to carious lesions in EG I, general predominance of type III collagen throughout the dentin of EG II and general predominance of type I collagen in the dentin of the CG. Qualitative analysis of the periodontal ligament noticed that the CG and EG I there was a predominance of type I collagen in the cervical third and type III in the apical third. In the EG II, the fibers were more disorganized and there was no more the previous dominance pattern. Quantitative analysis of the periodontal ligament noticed that the total of collagen type I showed significantly reduced in EG I (48.8 ± 6.1%) or EG II (49.1 ± 5.0%) in relation to the periodontal ligament of the CG (69.7 ± 6.3%) (p = 0.047). Total collagen type III showed significantly higher in EG I (51.2 ± 6.1%) or in EG II (50.9 ± 5.0%) in relation to the periodontal ligament of the CG (24.8 ± 5.1%) (p = 0.006). Conclusion: ionizing radiation promotes collagen changes in the dentin and periodontal ligament of teeth within the radiation fields of patients who have underwent head and neck RT.