Bisphosphonate-related osteonecrosis of the jaw: position paper from the Allied Task Force Committee of Japanese Society for Bone and Mineral Research, Japan Osteoporosis Society, Japanese Society of Periodontology, Japanese Society for Oral and Maxillofacial Radiology, and Japanese Society of Oral and Maxillofacial Surgeons

Successful treatment of bisphosphonate-related osteonecrosis of the jaw (BRONJ) patients with sitafloxacin: new strategies for the treatment of BRONJ

BRONJ has become a well-known, occasionally severe side effect of bisphosphonate therapy, as well as a clinical problem. Although treatment recommendations exist, no standard therapy has yet been established for BRONJ. Also, these recommendations identify several limitations that prevent clinicians from confidently diagnosing BRONJ. The aim of the present study was to establish a treatment approach in which all patients with exposed, infected bone or intraoral/extraoral fistulas were treated with sitafloxacin (STFX). We examined 20 BRONJ patients, fourteen with cancer and six with osteoporosis. We used the current updated definition of BRONJ (12), except that we included patients who had shown symptoms for a minimum of only one month, rather than two months. Thus half of our patients had infection with no exposed, necrotic bone in the oral cavity. We purposely excluded all patients exhibiting no signs of infection (current Stages 0 and 1). In addition, each potentially causative organism was isolated from pus collected from an intraoral or extraoral fistula in ten patients on their first visit to our department. 90% of the patients had received a course of treatment with common antibiotics. STFX was administered to all patients. We then re-evaluated the lesion every other week, to determine whether epithelialization was present. We recommended surgical treatment for cases without epithelialization within 4 weeks after the onset of administration of STFX even if bone was not exposed at the lesion. 19 of our 20 cases of Stages 2-3 BRONJ responded to 2-10 weeks of STFX treatment by entering either a remission or healed phase. While surgery was done on thirteen cases, seven others reached such phases without surgery. Every patient had at least one bacterial species that showed resistance to common antibiotics. All species in all patients were susceptible to STFX. Our results indicate that STFX, with or without minor surgery, gives a high probability of controlling infection in BRONJ patients with persistent infection after use of common antibiotics, leading to remission and/or complete healing in 95% of patients.

Surgical Therapy for Bisphosphonate-Related Osteonecrosis of the Jaw: Six-Year Experience of a Single Institution

PURPOSE

Bisphosphonates are drugs commonly used to treat osteoporosis, hypercalcemia of malignancy, and bone metastases. In some cases, its administration has been associated with osteonecrosis of the jaws. The management of medication-related osteonecrosis of the jaw (MRONJ) has not been completely elucidated, and its treatment can vary from no or limited surgery to more extensive surgery. The objective of the present study was to evaluate the efficacy of surgical therapy for patients presenting with MRONJ.

PATIENTS AND METHODS

A retrospective study was conducted that evaluated all MRONJ cases resulting from bisphosphonate use and treated by surgery from 2006 to 2012. All patients underwent surgery under general anesthesia.

RESULTS

A total of 33 patients with 46 MRONJ sites were evaluated. Most of the patients were women, with an age range of 39 to 83 years (mean 65.6 ± 10.6). Complete healing of the MRONJ region was observed in 40 of the 46 sites (87%), with partial improvement (symptom control and reduction of the exposed bone area) observed in 3 sites (6.5%), for a 93.5% clinical benefit rate. Of the remaining regions, 2 showed no significant changes, and 1 presented with a worse aspect compared with the patient's preoperative condition. Such cases were located in the posterior mandible region. The number of applications and type of bisphosphonate did not influence the treatment response.

CONCLUSION

The surgical approach to treating MRONJ showed a high rate of clinical control. Therefore, surgery should be considered as a therapy for some cases of this condition.

Prospective, mono-institutional study of the impact of a systematic prevention program on incidence and outcome of osteonecrosis of the jaw in patients treated with bisphosphonates for bone metastases

The aim of our study was to investigate the occurrence of osteonecrosis of the jaw (ONJ) after implementation of dental preventive measures before starting bisphosphonates (BPs) therapy and during treatment. All consecutive patients with bone lesions eligible for BPs treatment were prospectively evaluated. Before starting BPs, each patient underwent a strict dental preventive program with a specialized odontoiatric team. The odontoiatric evaluation identified patients with oral pathologies or inadequate oral hygiene and provided a dental preventive treatment. From April 2007 to April 2012, 254 patients were enrolled. After excluding patients due to previous BPs treatment, 212 patients with a mean age of 74 years (range 37-95) were included. On average, patients received 9.7 treatment cycles (range 1-48). No ONJ was recorded (0.0 %; 95 % confidence interval [CI] 0.0-1.4). Comparing this risk with that observed in a previous cohort who did not receive dental prevention (16/186, 8.6 %; 95 % CI 4.2-15.3 %), we observed clear efficacy in preventing ONJ (relative risk reduction: 100 %, 95 % CI 86-100 %, P < 0.0001). We developed a strict three-step prevention program that is able to decrease ONJ incidence and the need for destructive surgery with permanent sequelae. We demonstrated that ONJ could be effectively prevented. We recommend a mandatory preventive program involving a multidisciplinary team for all patients starting BPs.

Zoledronate but not denosumab suppresses macrophagic differentiation of THP-1 cells. An aetiologic model of bisphosphonate-related osteonecrosis of the jaw (BRONJ)

OBJECTIVES

Bisphosphonates and denosumab are antiresorptive drugs used for the treatment of osteoporosis and oncological tumors. A severe side effect is osteonecrosis of the jaw. Monocyte/macrophage dysfunction is considered to play a distinct role in osteonecrosis. THP-1 monocytic cells were used in this study to elucidate the influence of zoledronate and denosumab on phorbol-12-myrisate-13-acetate (PMA)-induced macrophage differentiation and function in real-time.

MATERIALS AND METHODS

Macrophagic differentiation of the THP-1 suspension cells was measured by cell adherence in the presence or absence of different concentrations of zoledronate (0.5, 5, 50 μM) and denosumab (1, 10, 20, 40 μg/mL) using the real-time xCELLigence system. Additionally, a live/dead staining was performed by fluorescence microscopy.

RESULTS

THP-1 cells demonstrated a regular initial PMA-induced differentiation to macrophages by live measurements of cell adherence and by an increase in CD68 surface expression as detected by flow cytometry. The addition of zoledronate led to cell detachment of the THP-1-derived macrophages in a dose-dependent manner in contrast to denosumab. Cell detachment was based on cell death as confirmed by live/dead staining, revealing elevated numbers of dead cells following addition of high zoledronate concentrations. However, denosumab did not deteriorate THP-1 cell viability.

CONCLUSION

Our results demonstrate that zoledronate but not denosumab suppresses monocytic THP-1 cell viability after macrophagic differentiation dose-dependently.

CLINICAL RELEVANCE

This is the first real-time study providing evidence for a dose-dependent immunosuppressive effect of zoledronate in contrast to denosumab on local macrophages.

Characteristics of the early stages of intravenous bisphosphonate-related osteonecrosis of the jaw in patients with breast cancer

OBJECTIVE

The clinical features of the early stages of bisphosphonate-related osteonecrosis of the jaw (BRONJ) in patients with breast cancer remain unclear. A retrospective cohort study was conducted of patients with breast cancer who received intravenous bisphosphonate (BP) treatment in a single center in order to clarify the status of the early stages of BRONJ.

MATERIALS AND METHODS

A BRONJ oral monitoring program was established in 247 breast cancer patients given intravenous BP treatment at the institution. The differences in age, BP treatment period, number of remaining teeth, oral hygiene status, presence of regular oral monitoring and the existence of suspected BRONJ (stage 0) among eight BRONJ and 36 non-BRONJ subjects who completed oral examinations were then compared.

RESULTS

BRONJ was observed in 0.4% of subjects on the first visit to the oral surgery clinic and in 3.2% of subjects during the follow-up period. Logistic regression analysis revealed that the odds ratio for identifying patients with BRONJ during follow-up by the presence of stage 0 at first visit was 24.0 (95% confidence interval [CI] = 3.6-161.7). The area under the receiver operating characteristic curve for identifying subjects with BRONJ by the presence of stage 0 was 0.82 (95% CI = 0.63-1.00).

CONCLUSION

The results suggest that patients with stage 0 BRONJ on the first visit may progress to advanced BRONJ during the follow-up period. The oral monitoring program may contribute to the early detection of BRONJ.

Bisphosphonate-Related Osteonecrosis of the Jaws and Its Array of Manifestations

PURPOSE

Bisphosphonate (BP) therapy in the treatment of bone diseases and malignancy may induce a major side effect known as bisphosphonate-related osteonecrosis of the jaws (BRONJ). A particular view of this condition is reported in this case series investigating eight patients. The aim of the study was to evaluate the BRONJ lesions concerning their aspects and progression. Also, identify if it is possible to predict the degree of severity in these cases.

METHODS

Patients were evaluated by their condition and systemic health. The lesions were evaluated in clinical and radiographic aspects. The patients were followed-up for 2 years.

RESULTS

The patients presented with specific peculiarities, and the BRONJ lesions varied in several characteristics. The BRONJ lesions ranged from simple to severe conditions, and the complicated cases presented with major pain, swelling, secondary infection and an extensive necrotic area, classified with high grade of severity.

CONCLUSIONS

The patients presented here confirm the existence of a relation between multiple features and BRONJ and to understand the whole process of aggravation, all systemic and local information have to be taken into account, together with all data related to the BP utilized. Regardless of the low incidence of this side effect in relation to osteoporosis treatment, in some cases, the BRONJ may become a severe condition and compromise the patient's quality of life.

Clinical aspects, imaging features, and considerations on bisphosphonate-related osteonecrosis risk in a pediatric patient with osteogenesis imperfecta

Osteogenesis imperfecta (OI) is a rare hereditary condition caused by changes in collagen metabolism. It is classified into four types according to clinical, genetic, and radiological criteria. Clinically, bone fragility, short stature, blue sclerae, and locomotion difficulties may be observed in this disease. OI is often associated to severe dental problems, such as dentinogenesis imperfecta (DI) and malocclusions. Radiographically, affected teeth may have crowns with bulbous appearance, accentuated constriction in the cementoenamel junction, narrowed roots, large root canals due to defective dentin formation, and taurodontism (enlarged pulp chambers). There is no definitive cure, but bisphosphonate therapy is reported to improve bone quality; however, there is a potential risk of bisphosphonate-related osteonecrosis of the jaw. In this study we report a case of OI in a male pediatric patient with no family history of OI who was receiving ongoing treatment with intravenous perfusion of bisphosphonate and who required dental surgery. In addition, we discussed the clinical and imaging findings and briefly reviewed the literature.

Atraumatic tooth extraction in patients taking bisphosphonates: a review of literature and experience with three cases

PURPOSE

Regev et al. first re-introduced the method of atraumatic tooth extraction with orthodontic elastics in 2008. Since then, the method has been mentioned regularly in literature. Nevertheless, the need for additional more detailed information remains.

METHODS

We present a review of literature and a retrospective analysis of our three patients receiving bisphosphonate medication. Two of our patients suffered from bisphosphonate-related osteonecrosis of the jaw (BRONJ). All three patients underwent atraumatic tooth extraction, which we describe in detail.

RESULTS

Regev et al. reported satisfactory results using the novel method. We removed six teeth in two patients with continued chemotherapy or bisphosphonate therapy in a time span of 26.2 ± 16.4 weeks successfully. None of the patients developed exposed bone in the follow-up (7.4 ± 0.2 months). In one case, the technique had to be discontinued due to increasing tooth soreness.

CONCLUSIONS

Atraumatic tooth extraction seems to be a safe method to prevent bone exposure, even in cases with BRONJ. The time required of our patients for exfoliation exceeded the time mentioned in literature considerably. This proved to be a major limitation. Our cases showed that patients with good compliance, no sore teeth, or painful BRONJ lesions, benefited from atraumatic tooth extraction. One of the method's major advantages might be the possibility to continue chemotherapy and bisphosphonate therapy throughout the treatment.

Oral toxicity produced by chemotherapy: A systematic review

Introduction: Antineoplastic chemotherapy remains one of the most widely used management strategies in cancer, either alone or in combination with other types of treatment. The main inconvenience of chemotherapy is its lack of selectivity, since it acts upon both tumor cells and rapidly multiplying normal cells such as bone marrow cells, hair follicle cells and oral and gastrointestinal mucosal cells. Material and method: An exhaustive search was made of the main oral toxic effects of chemotherapy in the PubMed-Medline, Cochrane Library and Scopus databases. A total of 1293 articles were identified, of which 333 met the study inclusion criteria. Results: The toxic effects of chemotherapy at oral mucosal level comprise mucositis, osteonecrosis of the jaws secondary to bisphosphonate use, susceptibility to infections, dental alterations, salivary and neurological disorders, dysgeusia and bleeding tendency. These complications have a negative impact upon patient quality of life, and in some cases can prove life-threatening. Conclusions: Evaluation of patient oral and dental health is essential before administering chemotherapy, in order to minimize the risk of oral and systemic complications of such treatment.

Key words:Chemotherapy, oral complications, dental, saliva and osteonecrosis jaw.

Epidemiology, clinical manifestations, risk reduction and treatment strategies of jaw osteonecrosis in cancer patients exposed to antiresorptive agents

 Osteonecrosis of the jaws (ONJ) is an adverse side event of bisphosphonates and denosumab, antiresorptive agents that effectively reduce the incidence of skeletal-related events in patients with metastatic bone cancer and multiple myeloma. Available data suggest that 0-27.5% of individuals exposed to antiresorptive agents can develop ONJ. There is increasing evidence that avoidance of surgical trauma and infection to the jawbones can minimize the risk of ONJ, but there are still a significant number of individuals who develop ONJ in the absence of these risk factors. Bone necrosis is almost irreversible and there is no definitive cure for ONJ with the exclusion, in certain cases, of surgical resection. However, most ONJ individuals are affected by advanced incurable cancer and are often managed with minimally invasive nonsurgical interventions in order to control jawbone infections and painful symptoms. This article summarizes current knowledge of ONJ epidemiology, manifestations, risk-reduction and therapeutic strategies. Further research is needed in order to determine individual predisposition to ONJ and clarify the effectiveness of available treatments.

Potential anti-osteoporotic effects of herbal extracts on osteoclasts, osteoblasts and chondrocytes in vitro

BACKGROUND

Osteoporosis (OP) is one of the most serious diseases in the modern world, and OP patients frequently suffer from fragility fractures in the hip, spine and wrist, resulting in a limited quality of life. Although bisphosphonates (BPs) are the most effective class of anti-bone-resorptive drugs currently available and the most commonly prescribed for the clinical treatment of OP, they are known to cause serious side effects such as bisphosphonate-related osteonecrosis of the jaw. Novel therapeutic materials that can replace the use of BPs have therefore been developed.

METHODS

We commenced an institutional collaborative project in which candidates of herbal extracts were selected from more than 400 bioactive herbal products for their potential therapeutic effects not only in OP, but also in oral and skeletal diseases. In the present study, we report on 3 Chinese medical herbal extracts from the root barks of Melia azedarach, Corydalis turtschaninovii, and Cynanchum atratum.

RESULTS

All of these extracts inhibited osteoclast proliferation and induced apoptosis by up-regulation of caspase activity and increase of mitochondrial pro-apoptotic proteins expression. Furthermore, the extracts enhanced differentiation, but did not affect proliferation of both osteoblasts and chondrocytes. The osteo-inducible effect was also observed in cultured primary bone marrow cells.

CONCLUSIONS

Although these extracts have been utilized in traditional Chinese medicine for hundreds of years, there are no reports to our knowledge, on their therapeutic effects in OP. In this study, we elucidate the potency of these herbal extracts as novel candidates for OP therapy.

A simple evaluation method for early detection of bisphosphonate-related osteonecrosis of the mandible using computed tomography

OBJECTIVES

The aim of this study was to establish a simple method for the early detection of bisphosphonate-related osteonecrosis of the jaw (BRONJ) using computed tomography (CT).

MATERIALS AND METHODS

CT images of the mandible were obtained from a total of 20 patients with BRONJ and 20 control subjects. BRONJ was classified into 2 groups, with bone exposure (Stage 1-3 BRONJ) or without (Stage 0 BRONJ). In each patient, 15 transaxial CT images were selected and 30 configured regions of interest (ROI) were identified. The ANOVA test was applied to test the relationship between the severity of systemic risk factors.

RESULTS

Regarding the local status of the mandible, significant differences were observed among the Stage 0 BRONJ, Stage 1-3 BRONJ, non-BRONJ and control groups in the cancellous bone CT radiodensity values, but there were no significant differences between the Stage 0 and Stage 1-3 BRONJ groups. In the cortical bone widths, significant differences were observed only between BRONJ and the controls.

CONCLUSIONS

Measuring cancellous bone CT radiodensity value has the potential to be a simple and quantitative method to detect the early stages of BRONJ.

Does an alkaline environment prevent the development of bisphosphonate-related osteonecrosis of the jaw? An experimental study in rats

OBJECTIVE

To investigate the preventive effect of locally applied sodium bicarbonate on bisphosphonate-related osteonecrosis of the jaw (BRONJ).

STUDY DESIGN

Thirty-six Sprague-Dawley rats were divided into 4 groups. Animals in group I received 0.1 mg/kg sterile saline 3 times per week for 8 weeks. Groups II, III, and IV received intraperitoneal zoledronate injection in the same manner with the same frequency and duration. The right first molar tooth was extracted in groups III and IV. One mL 8.4% sodium bicarbonate (SB) was applied to the extraction socket at the time of extraction in group IV. The effect of locally applied SB as an alkalizing agent was evaluated by histomorphometric analysis.

RESULTS

BRONJ was observed in none of the animals in the control groups, 67% of the animals in the tooth extraction group, and none of the animals in the local SB application group (P < .01).

CONCLUSIONS

Administration of locally applied SB had positive effects on the prevention of BRONJ in animals, but further studies are required to verify the effectiveness of this form of treatment before its use in humans.

Risk factors and indices of osteomyelitis of the jaw in osteoporosis patients: results from a hospital-based cohort study in Japan

BACKGROUND

Several studies have reported osteomyelitis of the jaw (OMJ) as a side effect of bisphosphonates (BPs), and the risk of oral BPs has been recently clarified. However, other systemic risk factors of OMJ remain unclear. Importantly, the possibility of risk classification based on the clinical characteristics of patients has not been explored. Here, we clarified risk factors of OMJ and evaluate the predictive accuracy of risk indices in osteoporosis patients.

METHODS

We performed sub-analysis using a database developed for a retrospective cohort study in patients taking medications for osteoporosis at Kyoto University Hospital. Risk indices for OMJ were constructed using logistic regression analysis, and odds ratios (OR) for OMJ cases and 95% confidence intervals (CI) were estimated. Potential risk factors included in the statistical analysis were age; sex; diabetes; use of oral BPs, corticosteroids, cancer chemotherapy, antirheumatic drugs, and biologic agents; and their interactions. Risk indices were calculated by the sum of potential risk factors of an individual patient multiplied by the regression coefficients. The discriminatory power of the risk indices was assessed by receiver operating characteristic (ROC) analysis.

RESULTS

In analysis of all patients, oral BPs (OR: 4.98, 95% CIs: 1.94-12.75), age (OR: 1.28, 95% CI: 1.06-1.60) and sex-chemotherapy interaction (OR: 11.70, 95% CI: 1.46-93.64) were significant risk factors of OMJ. Areas under the ROC curves of these risk indices provided moderate sensitivity or specificity regardless of group (0.683 to 0.718).

CONCLUSIONS

Our data suggest that oral BP use, age, and sex-chemotherapy are predictors of OMJ in osteoporosis patients. The risk indices are moderately high, and allow the prediction of OMJ incidence.

A retrospective study of digital subtraction technique to detect sclerotic changes in alveolar bone on intraoral radiographs of bisphosphonate-treated patients

OBJECTIVES

Several reports have suggested that sclerotic changes in cancellous bone of the jaw and thickening of the lamina dura are characteristic radiographic changes of an early silent stage of bisphosphonate (BP)-related osteonecrosis of the jaw. No quantitative evaluation has been reported to support this hypothesis. Emago(®) software (Oral Diagnostic Systems, Amsterdam, Netherlands) can perform digital subtraction on intraoral radiographs even if they were obtained by non-standardized radiography, provided the dimensional error is within a certain limit. The purpose of this study was to evaluate whether sclerotic changes of alveolar bone or thickening of lamina dura in patients using BP can be detected using the subtraction function of Emago.

METHODS

The authors selected 46 pairs of intraoral radiographs of the mandibular molar area in dental patients. All radiographs were obtained at intervals of 6 months or more. Among the 46 pairs, 7 pairs were from patients who were being treated with BP (study subjects), and 39 pairs were from patients who had not been using BP (controls). All pairs of radiographs underwent digital subtraction by Emago. The number of pixels of the sclerotic areas was counted and compared between subjects and controls.

RESULTS

The sclerotic changes were significantly distinguishable in two of the seven subjects (28.6%) using BP.

CONCLUSIONS

Digital subtraction function of Emago was able to detect sclerotic changes in alveolar bone. Therefore, it is suggested that the subtraction function of Emago is a useful tool for quantitatively detecting sclerotic changes that are observed at an early, silent stage of BP-related osteonecrosis of the jaw.

Bisphosphonate-related osteonecrosis of the jaws: legal liability from the perspective of the prescribing physician

Recently, it has been reported that patients administered with bisphosphonates (BP), in particular cancer patients receiving intravenous amino-bisphosphonates, as well as patients taking oral BP for prevention/treatment of diseases of altered bone turnover, may be affected by a significant adverse reaction-BP-related osteonecrosis of the jaws (BRONJ). This condition may cause high morbidity and detriment of quality of life. Its treatment is complex and often unsatisfactory, and prevention strategies may have limited effectiveness, if any; thus, BRONJ may become a source of litigation in the near future. Although most cases seem to be triggered by invasive dental procedures and oral health care providers are more exposed to malpractice claims and legal actions pursuant to BRONJ, the attribution of liability requires caution. In fact, types of possible negligence claims against oral health care providers have already been highlighted. However, according to the medico-legal methodology, since BRONJ is an adverse reaction to BP administration, the attribution of liability, if any, requires a comprehensive consideration of the chain of events and figures acting before, and potentially related to BRONJ. The physician prescribing BP at the start of this chain has specific duties which we are going to address, and breaching these duties may set the stage for potential liability claims.

Use of Ultrasonic Bone Surgery (Piezosurgery) to Surgically Treat Bisphosphonate-Related Osteonecrosis of the Jaws (BRONJ). A Case Series Report with at Least 1 Year of Follow-Up

This preliminary work documents the use of a powerful piezosurgery device to treat biphosphonate-related osteonecrosis of the jaw (BRONJ) in combination with classical medication therapy. Eight patients presenting 9 BRONJ sites were treated, 2 in the maxilla and 7 in the mandible. Reason for biphosphonate (BiP) intake was treatment of an oncologic disease for 5 patients and osteoporosis for 3. The oncologic and osteoporosis patients were diagnosed with BRONJ after 35-110 months and 80-183 months of BiP treatment, respectively. BRONJ 2 and 3 was found in 4 patients. Resection of the bone sequestrae was performed with a high power ultrasonic (piezo) surgery and antibiotics were administrated for 2 weeks. Soft tissue healing was incomplete at the 2-week control but it was achieved within 1 month. At the 1-year control, soft tissue healing was maintained at all patients, without symptom recurrence. One patient with paraesthesia had abated; of the 2 pa-tients with trismus, one was healed, severity of the second trismus abated. This case report series suggests that bone resection performed with a high power ultrasonic surgery device combined with antibiotics might lead to BRONJ healing. More patients are warranted to confirm the present findings and assess this treatment approach.

Evaluation of socket healing in patients undergoing bisphosphonate therapy: experience of a single Institution

OBJECTIVE

To assess the clinical features of exodontias performed in cancer patients who have been receiving intravenous bisphosphonates (BPs).

STUDY DESIGN

This is a retrospective cohort study using a sample of 20 patients receiving BPs who had 62 teeth extracted. An univariate analysis was applied to calculate socket healing time (HT), comparing among exodontias performed according to cause, such as periodontal disease or caries, type of BP, and use of corticosteroid. In order to analyze the influence of each variable on HT, multiple statistical analyses were performed through logistic multiple regression.

RESULTS

From the 62 tooth extractions performed, 5 exodontias had evolved to 4 sites of bisphosphonate-related osteonecrosis of the jaws (BOJ). Of another 57 exodontias without development of BOJ, HT was significantly better for tooth extraction performed in patients receiving corticosteroid (p= .01), for tooth extracted due to caries (p= .04), and for extractions under pamidronate (p= .03). Sockets after exodontias due to periodontal diseases had OR= 5.22 (95% CI 1.73-133.66, p=0.01) for delayed HT, exodontias performed under corticosteroid use had OR=0.04 (95% CI 0.01-0.40, p<0.001), and exodontias performed under zoledronate had OR=0.31 (95% CI 0.08-1.25, p=0.10).

CONCLUSIONS

Exodontias performed in patients under BP therapy had a low rate of BOJ occurrence. Zoledronate and periodontal diseases influence delayed socket healing. Adjuvant antibiotics could be relevant procedures aimed at reducing the risk of BOJ development.

Bisphophonates related osteonecrosis of the jaw

OBJECTIVE

With sporadic reporting of BPs related osteonecrosis of jaw and in absence of definitive guidelines regarding the management of such patients, the dentists and the oral and maxillofacial surgeons need to be updated about this issue. The objective of this article was to produce an updated bibliographic review of BPs related ONJ. This paper reviews the literature regarding the same for better understanding of the problem and its management.

BACKGROUND

Bisphosphonates (BPs) are potent inhibitors of bone resorption and are widely used in the treatment of osteoporosis and other diseases that cause bone mass loss, such as Paget's disease, bone metastases, and multiple myeloma, to prevent pathological fractures. With increasing use, evidence is emerging that patients taking BP drugs are at risk of developing osteonecrosis of the jaws (ONJs), sometimes occurring spontaneously, but more commonly following dental extractions or oral bone surgery.

MATERIALS AND METHODS

A bibliographic search was carried out using PubMed, Medline, and search engines ending in April, 2013. The search terms used were: Oral BPs, dental implants, and osteonecrosis.

CONCLUSION

On the basis of available literature, the management of patients on bisphosphonates requiring dental treatment is classified according to the duration of BPs treatment, method of administration of BPs etc. Dental treatments when planned carefully in such patients have a fair to good prognosis.

Eldecalcitol: newly developed active vitamin D(3) analog for the treatment of osteoporosis

INTRODUCTION

Eldecalcitol is an active vitamin D(3) analog, characterized by high stability in the circulation and also in the peripheral tissues, and by strong activity in increasing bone mass in osteoporotic patients. The objective of the present review was to evaluate the effect of eldecalcitol on bone compared with active vitamin D or placebo in preclinical and clinical studies.

AREAS COVERED

Eldecalcitol increased bone mineral density and reduced bone turnover markers greater than alfacalcidol and placebo. Interestingly, in a 3-year clinical trial, bone resorption marker remained suppressed during the eldecalcitol treatment, whereas bone formation markers gradually recovered after initial suppression. The incidences of vertebral fractures and wrist fractures in eldecalcitol-treated group were significantly lower than those in alfacalcidol-treated group by 26 and 71%, respectively. In the patients whose baseline bone turnover was low, eldecalcitol treatment did not further suppress bone turnover markers during the 3-year treatment period.

EXPERT OPINION

Eldecalcitol reduced wrist fractures much greater than alfacalcidol and one of the reasons may be a stronger effect of eldecalcitol on preventing falls. Although the effect of eldecalcitol on bone turnover markers was stronger than that of alfacalcidol or placebo, eldecalcitol is not a mere antibone resorptive agent, rather act as a bone turnover modulator.

Bisphosphonates-related osteonecrosis of the jaw in Korea: a preliminary report

Objectives

Bisphosphonates (BP) are widely used in medicine for inhibiting bone resorption; however bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a major side effect of BP. To date, there have been no specific reports on the incidence of BRONJ among Koreans. This study investigated the preliminary results from a nationwide survey of BRONJ in the Departments of Oral and Maxillofacial Surgery (OMFS) at individual training hospitals.

Materials and Methods

A total of 15 OMFS departments (10 from dental schools, 4 from medical schools, and 1 from a dental hospital) participated in a multi-centric survey. This study assessed every BRONJ case diagnosed between January 2010 and December 2010. The patient age and BP type were evaluated.

Results

A total of 254 BRONJ cases were collected. The majority of BRONJ cases were associated with oral BP therapy, while 21.8% of the cases were associated with intravenous administration. Alendronate was the drug most frequently related to BRONJ (59.2% of cases), followed by risedronate (14.3%) and zolendronate (17.0%). The average age of BRONJ patients was 70.0±10.1 years, with a range of 38-88 years of age. With the number of BP patients in Korea reported to be around 600,000 in 2008, the estimated incidence of BRONJ is at least 0.04% or 1 per 2,300 BP patients.

Conclusion

The results suggest that the estimated incidence of BRONJ in Korea is higher than the incidence of other countries. Future prospective studies should be carried out to investigate the exact epidemiological characteristics of BRONJ in Korea.

High-dose zoledronic acid narrows the periodontal space in rats

The aim of this experiment was to evaluate the histological effects of zoledronic acid on the periodontal space in rats. 40 male Wistar rats were divided into three zoledronic acid groups and a control group. Zoledronic acid was injected subcutaneously at doses of 10, 50, or 500 μg/kg once a week for 3 weeks. The rats were killed 1 or 9 weeks after the last injection. Histological examination of the periodontal space around the incisor tooth revealed that zoledronic acid did not inhibit tooth development. In the rats killed 1 week after treatment discontinuation, the periodontal space gradually narrowed in response to increasing zoledronic acid doses, and the changes were statistically significant according to ANOVA but not according to ANOVA with post hoc tests. The changes persisted in the high-dose zoledronic acid group despite zoledronic acid discontinuation, with significant differences identified by ANOVA and ANOVA with post hoc tests. Therefore, although zoledronic acid had an insignificant effect on tooth development, it had a significant effect on the periodontal space when high doses were administered. The results of this experiment may provide useful information for future investigations on the role of zoledronic acid in the osteonecrosis of the jaw.

Principles of oral surgery for prevention of bisphosphonate-related osteonecrosis of the jaw

OBJECTIVES

Principles and workflow are described to prevent bisphosphonate-related osteonecrosis of the jaw (BRONJ) when oral surgery is necessary in patients taking bisphosphonates.

MATERIAL AND METHOD

A total of 117 surgical procedures were performed on 68 patients taking bisphosphonates. The basis of the treatment was (1) use of perioperative antibiotics; (2) after dentoalveolar surgical procedures, bone edges were smoothed and mucoperiosteal flaps were prepared to ensure tension-free wound closure; (3) sutures were not removed until 14 days postsurgery; (4) long-term results were evaluated.

RESULTS

Ninety-seven percent of all procedures were simple and showed no complications. Only 3 patients with a long history of intravenous bisphosphonate medication developed BRONJ within 4 weeks after surgery. No patient receiving oral bisphosphonates developed BRONJ. No long-term failure was observed when primary wound healing was successful.

CONCLUSIONS

The high success rate of the described surgical procedures imply dentoalveolar surgery with low risk of development of BRONJ is possible for patients taking bisphosphonates.

Zoledronic acid enhances the effect of radiotherapy for bone metastases from renal cell carcinomas: more than a 24-month median follow-up

BACKGROUND

Renal cell carcinoma (RCC) is thought to respond unreliably to radiotherapy (RT). Zoledronic acid significantly reduces the risk of skeletal complications. This study investigated whether RT with zoledronic acid prolonged the time to bone-lesion progression in comparison with RT alone.

METHOD

Twenty-seven patients (34 lesions) with bone metastases secondary to RCC undergoing treatment with RT with or without zoledronic acid were retrospectively evaluated at two institutions between 1999 and 2009. Twelve patients were treated with RT alone from 1999 to 2008 (RT group). Fifteen patients were treated with RT and zoledronic acid from 2006 to 2009 (RT + Z group). The time to skeletal-related events and pain progression were assessed from patients' medical records.

RESULTS

The median (range) follow-up was 26 (3-75) and 24 (3-55) months in the RT and RT + Z groups, respectively. Three patients (three lesions) in the RT + Z group had skeletal-related events (SREs). In contrast, six patients (eight lesions) in the RT group had SREs. SREs comprised pathological fractures in five, additional surgeries in three, spinal cord or cauda equine compression in two, and repeat RT in one. There was a significant difference in SRE-free survival time and duration of site-specific pain response between groups.

CONCLUSIONS

RT combined with zoledronic acid significantly prolonged SRE-free survival and duration of pain response compared with RT alone in the treatment of osseous metastases from RCC.

Teriparatide therapy for bisphosphonate-associated osteonecrosis of the jaw in an elderly Japanese woman with severe osteoporosis

We report on the case of a severely osteoporotic elderly Japanese woman with bisphosphonate-associated osteonecrosis of the jaw (ONJ), who was treated successfully with teriparatide. A 79-year-old woman with severe osteoporosis and bisphosphonate-associated ONJ was treated with teriparatide after debridement of the necrotic tissue in the jaw bone. Computed tomography (CT) images revealed the bone defect in the mandible after debridement of the necrotic tissue associated with ONJ. According to the attending dentist, the ONJ healed after 2 months of therapy. After 3 months of treatment, a robust increase in the serum level of the bone formation marker, serum intact procollagen type 1 N-terminal propeptide, was noted and a repeat CT revealed improvement of the bone defect of the mandible. These results suggest the beneficial effects of teriparatide therapy in the severely osteoporotic elderly woman with ONJ.

Eldecalcitol normalizes bone turnover markers regardless of their pre-treatment levels

BACKGROUND

Three-year treatment with eldecalcitol has been shown to improve lumbar and total hip bone mineral density (BMD), decrease bone turnover markers, and lower the incidences of vertebral and wrist fractures in patients with osteoporosis more than with treatment with alfacalcidol under vitamin D repletion. The purpose of this study was to determine whether there was a risk of eldecalcitol causing severely suppressed bone turnover in osteoporosis patients with low pre-treatment levels of bone turnover markers.

METHODS AND RESULTS

Post-hoc analysis was conducted on the data from a 3-year, randomized, double-blind, active-comparator, clinical trial of eldecalcitol versus alfacalcidol under vitamin D repletion conducted in Japan. Enrolled patients with baseline measurements of bone turnover markers were stratified into tertiles according to their pre-treatment levels of serum bone-specific alkaline phosphatase, serum procollagen type I N-terminal propeptide, or urinary collagen-N-telopeptide. Eldecalcitol treatment rapidly reduced bone turnover markers, and kept them within the normal range. However, in the patients whose baseline values for bone turnover were low, eldecalcitol treatment did not further reduce bone turnover markers during the 3-year treatment period. Further long-term observation may be required to reach the conclusion. CLINICALTRIALS.GOV NUMBER: NCT00144456.

CONCLUSIONS

Eldecalcitol normalizes, but does not overly suppress, bone turnover regardless of baseline levels of bone turnover markers. Thus, it is unlikely that eldecalcitol treatment will increase the risk of severely suppressed bone turnover and therefore deterioration of bone quality, at least for a treatment duration of 3 years.

Long-term success of surgery in bisphosphonate-related osteonecrosis of the jaws (BRONJs)

OBJECTIVES

Bisphosphonates are associated with osteonecrosis of the jaw. Bisphosphonate-related osteonecrosis of the jaw (BRONJ) may be treated conservatively or by surgery.

PATIENTS AND METHODS

108 patients underwent surgery and 88 patients were followed for a mean period of 337 days. Age, gender, dental procedures, underlying disease, and the role of bisphosphonate treatment in the success of surgery were evaluated retrospectively.

RESULTS

Surgical treatment improved the stage distribution from 19% stage I, 56% stage II and 25% stage III to 59% intact mucosa, 19% stage I and 13% stage II and 8% stage III. The improvement in the stage of disease achieved by surgery was statistically significant. Further relevant parameters that favor a positive outcome of surgery were the event triggering the outbreak of BRONJ (p=0.05) and the underlying disease (p=0.05). BRONJ in the maxilla necessitated repeat surgery significantly earlier than did BRONJ in the mandible (p=0.03).

CONCLUSION

Effective surgery might improve the outcome of BRONJ, although prevention still is the most important aspect of this condition.

Effects of pamidronate on human alveolar osteoblasts in vitro

PURPOSE

Administration of bisphosphonates has recently been associated with the development of osteonecrotic lesions of the jaw (ONJ). To elucidate the potential contributions of osteogenic cells to the development and regeneration of ONJ, we have isolated primary cells from human alveolar and long/iliac bones, and examined the effects of pamidronate on cell viability, proliferation, osteogenesis, and wound healing.

MATERIALS AND METHODS

Primary human osteoblasts and bone marrow stromal cells were isolated from alveolar and iliac/long bone and marrow tissue. Cellular proliferation, alkaline phosphatase activity, apoptosis (terminal deoxynucleotidyl transferase dUTP nick end labeling, caspase-3, and 4,6-diamidino-2-phenylindole dihydrochloride assays) and wound healing in an in vitro scratch assay were assessed after exposure to pamidronate at a range of clinically relevant doses.

RESULTS

Primary alveolar osteoblasts proliferated at significantly higher rates than long/iliac bone osteoblasts in vitro. Upon exposure of alveolar osteoblasts and long/iliac bone marrow stromal cells to pamidronate for more than 72 hours, we have observed significantly decreased cell viability, proliferation, osteogenesis, and in vitro wound healing at ≥6 × 10(-5) mol/L pamidronate, with the induction of apoptosis in approximately 20% of cell population.

CONCLUSIONS

The remodeling activity of alveolar bone, indicated by higher proliferation of alveolar osteoblasts, could be negatively affected by exposure to high concentrations of pamidronate over extended periods. The absence of anabolic effects of pamidronate on alveolar osteoblasts and the induction of apoptosis in osteogenic cells could negatively affect bone balance at this site and contribute to osteonecrosis of the jaw.

Three years of treatment with minodronate in patients with postmenopausal osteoporosis

The objective of this study was to determine the safety and efficacy of long-term minodronate treatment in women with postmenopausal osteoporosis based on re-analysis of a phase III 2-year clinical trial with a 1-year extension. Women aged 55-80 years old with fragility fractures were enrolled and randomized to take 1 mg minodronate or placebo once a day in the original 2-year study. The subjects who completed the 2-year study were invited to participate in an additional 1-year extension in which all subjects were to receive minodronate. Finally, a total 380 subjects completed the extension study (186 from the placebo group and 194 from the minodronate group). Fracture results observed in the extension study were consistent with those observed in the first 2 years in minodronate group. In contrast, the placebo/minodronate group showed a decreased incidence of new vertebral fractures during year 3 compared to that in year 2. In the patients who received minodronate in the original 2-year study, lumbar bone mineral density (BMD) increased consistently during year 3 and bone turnover markers decreased within the first 6 months and remained constant thereafter over 3 years. Similar positive effects of minodronate on BMD and bone turnover markers occurred when therapy was initiated in the placebo/minodronate group. No new safety concerns observed during the extension period compared to the safety observations made during the 2-year study. It was concluded that daily administration of 1 mg oral minodronate is safe and well tolerated, and that the efficacy of this dose in reducing vertebral fracture risk in postmenopausal women over 2 years is sustained with continuing treatment.