Utility of injectable bisphosphonates in enhancing orthodontic retention in a goat model: A split-mouth study

ObjectiveThe aim of this study was to evaluate the utility of bisphosphonates in reducing relapse after orthodontic tooth movement when injected intra-periodontally in a goat model.MethodsRight and left second incisors of four goats were extracted and the first and third incisors were approximated orthodontically and retained. A bisphosphonate gel was injected into the mesial and distal periodontal spaces of first and third incisors on one side, while the first and third incisors of the other side received normal saline as a control. After 12 weeks of retention, the orthodontic appliance was removed and teeth were relieved from any active force. Following 6 weeks from appliance removal, millimetric measurements were performed to calculate the amount of relapse of orthodontically moved incisors. Histological and microcomputed tomographic examination was performed to assess the periodontal space and surrounding alveolar bone of the study and control incisors.ResultsThe millimetric measurements and microcomputed tomographic scanning revealed that the orthodontically moved incisors in the side of bisphosphonate injection had significantly less relapse (p ≤ 0.05) and significantly narrower periodontal ligament width (p ≤ 0.05) than in the control side, respectively. Histologically, newly formed bone projecting into the periodontal ligament was observed in the side of bisphosphonate injection with newly formed cementum overlying areas of resorbed cementum.ConclusionThe results suggest that bisphosphonate injection has the potential to enhance post-orthodontic stability and repair of root resorption following orthodontic treatment.     

Measurement of Bone Mineral Density by Dual X-ray Absorptiometry in Paget's Disease Before and After Pamidronate Treatment

Third-generation bisphosphonates are now currently used in the treatment of Paget's disease of bone. Dual X-ray absorptiometry may make it possible to quantify the action of these bisphosphonates on bone mineral density (BMD) in pagetic and nonpagetic bone. We used Lunar DPX, a total-body software program (automatic analysis and/or manual windows according to the site and bilateral or unilateral pagetic involvement) to study BMD in 28 patients (18 men, 10 women, mean age 69.8 years) with Paget's disease before and 6 months after infusions of 60 mg (alkaline phosphatase <350 IU) or 120 mg (ALP >350 IU) of pamidronate. Before treatment, in the 28 patients, the BMD of trabecular pagetic bone was 25% higher than that of nonpagetic bone; in cortical pagetic bone the BMD was 35% higher. After treatment, the BMD of trabecular pagetic bone increased by only 1.17%. the BMD of cortical pagetic bone increased by 1.37% whereas nonpagetic cortical bone lost 0.84%, independently of the levels of parathyroid hormone or the administration of calcium and vitamin D. Received: 17 March 1998 / Accepted: 12 March 1999     

Awareness,perceptions and attitudes toward medication-related osteonecrosis of the jaw among physicians who treat osteoporosis

Osteoporosis is the most common indication for antiresorptive drugs (ARDs). Medication-related osteonecrosis of the jaw (MRONJ) is a severe complication of ARDs. Multiple risk factors can increase the risk of MRONJ, one of which is the duration of ARD intake, which is usually prolonged for osteoporosis cases. Prevention of MRONJ relies on collaborative care between treating physicians and dental practitioners. Therefore, knowledge about MRONJ and its prevention strategies is crucial for both teams.AimThis study aimed to assess the knowledge and attitudes of physicians toward MRONJ in osteoporosis patients. Another aim was to develop recommendations for the prevention of MRONJ.Materials and methodsThrough an online survey, basic information such as the practice location, training, knowledge, perceptions, and attitudes of physicians regarding ARDs and MRONJ in osteoporosis patients was collected. Statistical analysis was performed for all variables, and their correlations were explored.ResultsA total of 221 physicians participated in the survey: 34.8% were rheumatologists, 25.3% were endocrinologists, 8.6% were family medicine physicians, 5.9% were orthopedists, and 5.9% were internal medicine physicians. Of them, 58.0% reported more than 6 years of experience. Only 78.7% were aware of MRONJ and recognized that bisphosphonates (BPs) can contribute to MRONJ. In contrast, 56.0% recognized denosumab as a causative factor for MRONJ. Duration of ARD therapy and pre- and post-ARD dental care were known to influence the risk of MRONJ by 62% and 65.6% of the participants, respectively. Only 41.6% and 31.2% of participants informed patients about MRONJ prior to BP and denosumab therapy, respectively. Only 25.3% and 20.8% referred patients to dentists before BP and denosumab therapy, respectively. Overall, 65.6% of the participants had a negative attitude toward MRONJ, and 34.4% had a positive attitude. A positive attitude was mostly observed among rheumatologists (55.8%) compared to other specialists (p <0.001). More years of experience were associated with a higher level of knowledge and positive attitude.ConclusionThe findings of this study identified a notable gap in the awareness, knowledge and attitudes of physicians regarding MRONJ in osteoporosis patients. Continuing education programs about ARDs and MRONJ risk are highly recommended.     

双膦酸盐临床试验最新进展——2011年SABCS会议速递

2010年,SABCS最大的新闻之一就是AZURE试验。试验结果表明唑来膦酸对乳腺癌复发和整体存活率无影响。然而,亚组分析显示,对绝经后妇女的（绝经后5年以上）复发和生存有显著效果,但对绝经前妇女无影响^[1]。     

二膦酸盐对正畸治疗中牙根吸收影响的系统评价

目的：系统评价二膦酸盐对正畸治疗中牙根吸收的影响。方法：检索PubMed等数据库中关于二膦酸盐对正畸治疗中牙根吸收影响的随机对照试验文献，并对纳入文献进行质量评估。结果：共纳入9项研究，其中3项为中等级质量，6项为低等级质量。药物剂量、作用力大小和方式、牙根吸收测量方法不同导致只能进行定性分析。二膦酸盐对正畸诱导的牙根吸收的抑制作用具有剂量和时间依赖关系。结论：二膦酸盐可能减轻正畸治疗中牙根吸收的严重程度，但由于纳入文献的质量不高，该结果的临床推衍存在局限性，仍需统一研究方法的大样本、长时间的随机对照实验以进一步研究。     

Case series of medication-related osteonecrosis of the jaw (MRONJ) patients prescribed a drug holiday

The role of a drug holiday in the management of medication-related osteonecrosis of the jaw (MRONJ) remains controversial. Current UK guidance does not recommend this practice given the lack of conclusive evidence, and potential risk of skeletal-related events or cancer metastasis. This paper aims to describe a series of fifty patients with confirmed MRONJ who were prescribed a drug holiday as part of their management. Data were collected on exposures including: anti-resorptive and/or anti-angiogenic drug history, duration of drug, method of administration, concurrent therapy, MRONJ stage, management of MRONJ and duration of drug holiday. The primary outcome was complete healing as documented in the clinical notes. Multivariate Cox regression analysis was performed to evaluate the association between exposures and primary MRONJ outcome. Models were adjusted for age, sex, and index of multiple deprivation. Survival analysis was performed using a log-rank test, censoring any patients with no primary outcome recorded (p < 0.05). A total of 44% of patients stopped their medication for >36 months. Over half of all MRONJ cases presented in the posterior mandible and dental extraction was the most common precipitating factor (76%). Almost three-quarters (72%) of patients achieved complete healing. MRONJ recurrence (new site) was reported at 30%, mainly in those with incomplete healing of the initial area. There was a lack of evidence for an association between all recorded exposures and the primary MRONJ outcome using multivariate Cox regression. Similarly, we did not demonstrate evidence for an association between the duration of the drug holiday and MRONJ outcome. Our results support published guidelines, which do not recommend the discontinuation of bone modifying drugs for the prevention of MRONJ, or as part of treatment for established MRONJ.