Avaliação dos efeitos da deficiência de testosterona sobre os tecidos periodontais de ratos castrados e com periodontite experimental

Abstract

Testosterone is the principal male sex steroid hormone involved in differentiation, sexual development and control of male reproductive functions. In addition to its role in reproductive endocrinology and fertility, testosterone is an important hormone in the regulation and functioning of other organs and tissues including the kidney, heart, skeletal muscle, immune system and oral and periodontal tissues. Periodontitis is a disease characterized by inflammation of the periodontal tissues and associated with dental decay, are mainly responsible for the loss of dental elements. The relationship between sex steroids hormones and periodontal disease has been intensively investigated in females, however studies in males are still scarce. Therefore, the aim of the present project is to analyze the influence of testosterone deficiency on bone loss and histological structure of the periodontal tissues of castrated rats and experimental periodontitis. Twenty-eight male Wistar rats, provided by the Central Biotherium of Unioeste were used. At 80 days of age the animals were separated in four experimental groups, with 7 animals per group: no ligature control (CON), ligature control CON + LIG), no ligature castrated (CAST) and ligature castrated (CAST + LIG). At 90 days of age was held orchiectomy in appropriate groups. Sixty days after castration, the periodontal disease was induced by ligature technique. At the end of experimental period (90 days after castration), the animals were weighed and euthanized in a CO2 chamber. The mandible was removed, dissected, separated into left and right, were fixed by immersion in 10% buffered formalin for 24 hours, decalcified and processed for histological and radiological techniques. The results of this study showed that ligature model was effective 13 in inducing periodontitis in the animals. The food intake profile was similar between groups. The animals of CAST and CAST + LIG groups showed significant reduction in body weight at the end of experimental period, when compared with the groups CON and CON + LIG. Castration resulted in a significant bone loss in animals, which was accentuated with the induction of periodontal disease. Animals with periodontal diseases presented increased of gingival epithelium and connective tissue area, compared to animals without the disease. We conclude that testosterone is a physiological regulator important of alveolar bone metabolism. Testosterone deficiency in synergism with periodontal disease increases alveolar bone resorption and alters the thickness of gingival epithelium.Key