Efeito da administração de pentoxifilina e α-tocoferol na osteonecrose de mandíbula induzida por bifosfonato: antes e depois da exodontia

Abstract

This study evaluated the effect of the administration of pentoxifylline and α-tocopherol (PENTO) before or after tooth extraction, in the therapy of medication-related jaw osteonecrosis (MRONJ) in rats submitted to the application of zoledronic acid (AZ). Sixty Wistar rats were divided into three prevention groups (Control, BF and BF + PENTO / P) and three treatment groups (Control, BF and BF + PENTO / T), with 10 animals each. 0.1 mg / kg of AZ was applied twice a week for 12 weeks in the BF and BF + PENTO groups. On the 6th week, all animals underwent extraction. BF + PENTO / P received 50 mg / kg / day of pentoxifylline and 80 mg / kg / day of α-tocopherol one week before the procedure, until euthanasia, at 12 weeks. BF + PENTO / T received the same PENTO protocol from the 12th week, ending with 16 weeks. The presence and severity of osteonecrosis was assessed by clinical, imaging and histological analysis of the jaw. Treatment with PENTO, after extraction, reduced the histological incidence of osteonecrosis by 50%. In addition, the BF + PENTO / T group has been shown to decrease the percentage of empty osteocyte gaps and the necrotic area, decrease the presence of bone sequestration and increase the number of osteocytes and alveolar blood flow, reducing the severity of MRONJ (p <0.05). In the BF + PENTO / P group, there was only a reduction in the percentage of empty gaps (p <0.05). The effect of pentoxifylline and α-tocopherol, when administered before extraction, was not observed in the prevention of MRONJ. However, the application of pentoxifylline and α-tocopherol as a treatment, after extraction, decreased the radiological and histological incidence of MRONJ, in addition to reducing the disease severity score. This effect was attributed to the increase in osteocytes and blood flow in the extraction area.