Zoledronic acid induced osteonecrosis of tibia and femur

Ozone Improved Bone Dynamic of Female Rats Using Zoledronate

The aim of this study was to analyze the effect of ozone (OZN) therapy on the dynamics of bone tissue in ovariectomized rats treated with zoledronic acid (ZOL). Female Wistar rats aged 6 months (n = 110) were subjected to bilateral ovariectomy (OVX). At month 3 post-OVX, 10 animals were euthanized to characterize the bone tissue architecture using microtomography (micro-CT). The remaining animals were divided into two groups: ZOL group, administered with ZOL (100 μg/kg body weight); saline (SAL) group (0.45 mL of SAL solution), both for 28 days. At month 3 post-treatment, 10 animals from each group were euthanized to characterize the bone architecture using micro-CT. The remaining animals were divided into the following groups: ZOL (n = 20), ZOL + OZN (n = 20); SAL (n = 20), and SAL + OZN (n = 20). The animals in ZOL + OZN and SAL + OZN groups were intraperitoneally administered with OZN (0.7 mg/kg body weight) once every 2 days. On days 30 and 60, six animals from each group were euthanized for analysis and structural characterization of bones in the femoral head and spine. Some samples of the femoral neck were subjected to biomechanical tests, while some samples were analyzed under a laser confocal microscope. The other samples collected from the femoral neck and spine were analyzed for area of neoformed bone and used for performing inflammatory cell and osteocyte counts. Data were submitted to statistical analysis considering a significance level of p < 0.05. Bone volume percentage and osteocyte and inflammatory cell counts were upregulated in the femoral head region of the ZOL + OZN group. Biomechanical analysis of the femoral neck revealed that the modulus of elasticity was similar between the ZOL and ZOL + OZN groups but differed significantly between the SAL and SAL + OZN groups. The positive areas for calcein and alizarin in the ZOL and ZOL + OZN groups were higher than those in the SAL and SAL + OZN groups. This suggested a positive synergistic effect of OZN and ZOL on the maintenance of bone mass and restoration of bone tissue vitality in ovariectomized rats.

What is the impact of bisphosphonate therapy upon dental implant survival? A systematic review and meta-analysis

OBJECTIVE

A systematic review and meta-analysis are carried out to assess the scientific evidence that bisphosphonate therapy can decrease the success rate of dental implants.

MATERIAL AND METHODS

The PubMed (Medline) database was used to search for articles published up until February 22, 2014. The meta-analysis was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). The Newcastle-Ottawa scale (NOS) was used to assess study quality.

RESULTS

The combinations of search terms resulted in a list of 256 titles. Fourteen finally met the inclusion criteria and were thus selected for inclusion in the systematic review. Eight studies (six retrospective and two prospective) were included in the meta-analysis, with a total of 1288 patients (386 cases and 902 controls) and 4562 dental implants (1090 dental implants in cases and 3472 in controls). The summary odds ratio (OR = 1.43, P = 0.156) indicates that there is not enough evidence that bisphosphonates have a negative impact upon implant survival. According to the number need to harm (NNH), over 500 dental implants are required in patients receiving bisphosphonate treatment to produce a single implant failure.

CONCLUSION

Our results show that dental implant placement in patients receiving bisphosphonates does not reduce the dental implant success rate. On the other hand, such patients are not without complications, and risk evaluation therefore must be established on an individualized basis, as one of the most serious though infrequent complications of bisphosphonate therapy is bisphosphonate-related osteonecrosis of the jaws. Given the few studies included in our meta-analysis, further prospective studies involving larger sample sizes and longer durations of follow-up are required to confirm the results obtained.

Bisphosphonate Related Osteonecrosis of the Jaw: An Update

OBJECTIVES

The aim of this paper is to summarize different diagnostic criteria as well as probable aetiopathogenesis of bisphosphonates related osteonecrosis of the jaw.

MATERIALS AND METHODS

The electronic search of peer-reviewed journals were performed in MEDLINE (PubMed) database in order to find the relevant articles on bisphosphonates related osteonecrosis of the jaw (BP-related ONJ). The search was restricted to English language articles, published from January 2002 to May 2013. On the basis of these articles, probable aetiopathogenesis and different diagnostic criteria of BP-related ONJ were summarized.

RESULTS

BP-related ONJ is related to the development of avascular necrosis or dead jaw bones. In recent literature many given hypotheses show the aetiopathogenesis and diagnosis of BP-related ONJ which are interlinked and have multifactorial nature. Their diagnosis revolves around four main diagnostic criteria that differentiate it from other conditions which can delay bone healing.

CONCLUSIONS

Factors like potency of bisphosphonates, biology of jaw bone, antiangiogenic property of bisphosphonates and soft tissue toxicity in combination with present infection, other drugs, pre-existing pathologies, compromised immune response and dentoalveolar trauma may lead to development of BP-related ONJ.

When the tumour is not the culprit: avascular necrosis of the hip in a patient with castration-resistant prostate cancer

Avascular necrosis (avn) of the hip is a well-documented side effect of corticosteroid therapy, but it has also been described as a complication of radiation and chemotherapy. Many prostate cancer patients undergo treatment with all three of those therapeutic modalities, and yet reported cases of avn of the hip in prostate cancer patients are rare. Symptoms that might potentially alert physicians to this complication are nonspecific and may be attributed to cancer progression, in particular to progressive bone metastasis.Here, we report on a 79-year-old man diagnosed with castration-resistant prostate cancer whose diagnosis of avn of the hip was confounded by his underlying malignancy. We discuss risk factors and diagnostic clues in this differential diagnosis of acute hip pain in patients with castration-resistant prostate cancer. Physicians might maintain a high index of suspicion for avn of the hip in prostate cancer patients presenting with new-onset hip pain. Surgical intervention may help to prevent the appearance of avn-associated pain and the negative impact of advanced avn on overall quality of life.

Osteonecrosis of the jaws in patients treated with bisphosphonates

The literature describes an increasing presence of bisphosphonate-induced osteonecrosis of the jaws (ONJ), characterized by the exposure for over 8 weeks of necrotic bone in the maxillofacial region, after bisphosphonate therapy, in the absence of prior maxillary radiotherapy. The present literature review examines the etiopathogenesis, risk factors, clinical forms, diagnosis, treatment and prevention of bisphosphonate-induced ONJ. In addition, a review is made of all the series involving over 15 patients diagnosed with this disorder between 1 January 2011 and 15 May 2011. A PubMed-Medline search was carried out with the following key words: “bisphosphonates” and “osteonecrosis”. The appearance of osteonecrosis is a serious complication, with an increasing incidence, that affects patient quality of life and causes important morbidity. All patients treated with bisphosphonates are at risk of developing osteonecrosis as a result of such medication. This potential complication therefore should be explained to the patient by both the prescribing physician and the dental surgeon in charge of oral treatment, with the obtainment of informed consent in all cases.

Key words:Osteonecrosis of the jaws, bisphosphonates, etiopathogenesis, prevention, treatment.

A review of the clinical implications of bisphosphonates in dentistry

Bisphosphonates are drugs that suppress bone turnover and are commonly prescribed to prevent skeletal related events in malignancy and for benign bone diseases such as osteoporosis. Bisphosphonate associated jaw osteonecrosis (ONJ) is a potentially debilitating, yet poorly understood condition. A literature review was undertaken to review the dental clinical implications of bisphosphonates. The present paper briefly describes the postulated pathophysiology of ONJ and conditions with similar clinical presentations. The implications of bisphosphonates for implantology, periodontology, orthodontics and endodontics are reviewed. Whilst bisphosphonates have potential positive applications in some clinical settings, periodontology particularly, further clinical research is limited by the risk of ONJ. Prevention and management are reviewed, including guidelines for reducing cumulative intravenous bisphosphonate dose, cessation of bisphosphonates prior to invasive dental treatment or after ONJ development, and the use of serum beta-CTX-1 in assessing risk. In the context of substantial uncertainty, the implications of bisphosphonate use in the dental clinical setting are still being determined.