RESUMO
Bisphosphonates are used in cases of osteoporosis, multiple myeloma, metastatic carcinoma to the skeleton, etc. The patients with nitrogen-containing bisphosphonates are a greater risk for osteonecrosis of the jaws. Osteonecrosis is considered to be one of the side effect of the bisphosphonate the most common affected jaw is mandible. The primary reason for the osteonecrosis of the jaw is basically due to the over suppression of bone turnover rate. Trauma, tooth extractions, and poor oral hygiene is also considered to be another co-factor which precedes the osteonecrosis of the jaw in the patients of bisphosphonate therapy. So, preventive measure as a reduction of oral microbial load and reduction foci of infection is mandatory step before the treatment of bisphosphonate therapy.
RESUMO
Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a condition found in patients who have received intravenous and oral forms of bisphosphonate therapy for various bone-related conditions. BRONJ, manifests as exposed, nonvital bone involving the maxillofacial structures. The mandible is more commonly affected than the maxilla (2:1), and 60% of cases are preceded by a dental surgical procedure. The signs and symptoms that may occur before the appearance of clinically evident osteonecrosis include changes in the health of periodontal tissues, nonhealing mucosal ulcers, loose teeth and unexplained soft-tissue infection. Although, the definitive role of bisphosphonates remains to be elucidated, alteration in bone metabolism with surgical insult or prosthetic trauma appears to be key factors in the development of BRONJ. The significant benefits that bisphosphonates offer to patients clearly outbalance the risk of potential side effects; however, any patient for whom prolonged bisphosphonate therapy is indicated, should be provided with preventive dental care in order to minimize the risk of developing this severe condition. This article provides a review of current developments about the pathogenetic, clinical, management and preventive aspects of BRONJ.
RESUMO
PURPOSE: The purpose of this study was to investigate the effect of different administration duration of alendronate on initial wound healing and new bone formation of extraction socket in rats. MATERIALS AND METHODS: Fifteen male Sprague-Dawley rats (body weight 130-140 g, 4 weeks old, male) were divided into control group (no alendronate administration) and experimental group (alendronate administration). Experimental group was subdivided into 1 week administrated group, 2 week administrated group, 4 week administrated group and 6 week administrated group according to duration of administration. For the experimental groups, during the designated time period (at the time of extraction, 1 week before extraction, 3 week before extraction and 5 week before extraction) till 1 week after extraction, rats were subcutaneously injected with Alendronate at the dose of 1.0 mg/Kg three times a week. Each specimen from 6 week experimental group and control group were used for microarray analysis, and other specimens were used for histological analysis. The rate of new bone formation within the extraction site and bone loss activity was analyzed using TRAP staining. Statistical analysis was performed using Kruskal Wallis test. (alpha=.05) RESULTS: After one week from the time of extraction, the rate of new bone formation within extraction site for the control group (16.77% +/- 1.36%) compared to the 4 week experimental group (14.99% +/- 6.26%) was lower. However, no statistically significant difference was found. Increase in the number of inactive lacuna (empty lacuna) and decrease in the number of TRAP positive cell were identified with increased duration of administration. There was no significant difference. CONCLUSION: The results of this study showed as the duration of Alendronate administration increased the rate of new bone formation decreased with loss of bone activity and reduced number of osteoclast.