Prevention of bisphosphonate-related osteonecrosis of the jaw (BRONJ): evaluation of the effectiveness of different substances in rats

• Ano de defesa: 2020
• Autor(a) principal: Weiss, Suyany Gabriely
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Positivo; Brasil; Pós-Graduação; Programa de Pós-Graduação em Odontologia Clínica; UP
• Palavras-chave em Português: Odontologia; Osteonecrose; Difosfonatos; Pentoxifilina; Tocoferóis; CNPQ::CIENCIAS DA SAUDE::ODONTOLOGIA
• Link de acesso: https://repositorio.cruzeirodosul.edu.br/handle/123456789/2177

Bisphosphonate-related osteonecrosis of the jaws (BRONJ) is a serious complication associated with dental intervention and the long-term use of bisphosphonates, a class of drugs used to treat bone pathologies, such as osteoporosis and bone metastases. The purpose of this study is to evaluate the effectiveness of substances in preventing BRONJ. Thirty-six (n = 36) Wistar rats were used, females (n = 18) and males (n = 18). All rats received a weekly intravenous injection of 0.3 mL via a caudal vein of zoledronate (80 μg / kg body weight in PBS) for 8 weeks. Then, the animals underwent surgery to remove the first and second right and left mandibular molars to induce osteonecrosis. Males and females were equally distributed according to the substance in two large groups: biochelating biomaterial (n = 12), in a split-mouth study, and association of pentoxifylline and tocopherol (PENTO) (n = 12) in a case-control study. The bio-chelating group received a local application of 17% EDTA on the right side after extractions at the time of surgery while the left side received irrigation with saline solution. Twelve animals in the PENTO group received a combined suspension of the two substances (5.71 mg pentoxifylline and 7.14 IU tocopherol) via gavage once daily for 6 weeks. Twelve animals were allocated to a control group for the PENTO that received weekly intraperitoneal saline applications, once a week for 6 weeks. Clinical assessments were made by assessing the presence of the following characteristics: bone exposure, inflammation, suppuration, bone sequestration and epithelialization. In addition, the mesio-distal distances as well as the buccal-lingual bone exposure were obtained for each animal. The data were submitted to statistical analysis with a significance level of 0.05. It was possible to observe that in the bio-chelating biomaterial group there was no statistically significant difference in relation to the clinical data for bone exposure, bone sequestration, suppuration, inflammation and epithelialization (p> 0.05). Regarding the size of bone exposure, there was no statistically significant difference between the right and left sides (p = 0.197). The PENTO group demonstrated a lower incidence of bone sequestration when compared to the control (p = 0.006), no other statistically significant difference was obtained in relation to the others observed clinical data (p> 0.05). The PENTO group showed even less bone exposure on the buccal-lingual aspect (p = 0.041) when compared to the control. It is concluded that the PENTO group had more favorable clinical results related to BRONJ when compared to the control.