Prevalence and risk factors of medication-related osteonecrosis of the jaw in osteoporotic and breast cancer patients: a cross-sectional study.

PURPOSE: Medication-related osteonecrosis of the jaw (MRONJ) has been reported as a side effect of bisphosphonate (BP). The aim of this study was to identify the prevalence of MRONJ in women taking BP for osteoporosis and for metastatic breast cancer and correlate it with risk factors and biochemical markers of bone metabolism. METHODS: Patients taking oral or intravenous BP with osteoporosis (G1; n = 153; median 72.8 years) and with metastatic breast cancer (G2; n = 134; median 58.2 years) had their hospital charts reviewed, were submitted to dental inspection, and answered a health questionnaire. Fasting blood samples were randomly collected from both groups to measure osteocalcin, carboxy-terminal cross-linking telopeptide of type I collagen, intact parathyroid hormone and procollagen type 1 amino-terminal propeptide (P1NP), 25 hydroxyvitamin D (25OHD), creatinine, and total calcium. RESULTS: G1 was older (p = 0.001) and had more cases of diabetes (p = 0.043). P1NP was higher (p = 0.022) and 25OHD lower (p = 0.004) in G2 compared with G1. MRONJ was not found in the G1, whereas 4 cases (3%) were detected in G2. Positive risk factors for MRONJ were number of BP doses and number of visits to the dentist and dental extractions. The biochemical parameters, however, could not identify those who developed MRONJ. CONCLUSIONS: The prevalence of MRONJ was 3% in women with metastatic breast cancer receiving BP. No cases were identified in women receiving oral BP chronically for osteoporosis. P1NP was higher in women with metastatic breast cancer, even during treatment with antiresorptives, but could not differentiate those with MRONJ.

Changes in serological bone turnover markers in bisphosphonate induced osteonecrosis of the jaws: A case control study.

BACKGROUND: There are a lot study confirmed the relationship of bone serum markers changes and skeletal irregularities. But there is no sufficient case control studies about the role of these markers on bisphosphonate induced osteonecrosis of jaws (BRONJ). AIMS: The aim of this study is to find out if there is any derangement of bone markers in bisphosphonate-treated patients with ONJ. METHODS: We obtained serum bone markers and other relevant endocrine assays on 20 patients with osteonecrosis of the jaw (ONJ) and 20 randomized healthy volunteers. All of the ONJ group treated with zoledronic acid and had been withdrawn from bisphosphonate for at least 6 months. Diagnostic criteria for ONJ were those formulated by the American Association of Oral and Maxillofacial Surgeons. Serum levels of several indices of bone remodeling were evaluated using commercial enzyme-linked immunosorbent assays. The biochemical assays were performed on N-Telopeptides of type I collagen (NTX), bone-specific alkaline phosphatase (ALP), calcitonin, osteocalcin, intact parathyroid hormone (PTH), T3, T4, TSH, and Vitamin D 25 hydroxy (Vit-D). RESULTS: In ONJ group, PTH level is statistically higher and TSH, Vit-D, osteocalcin and NTX levels statistically lower compared to control group. CONCLUSION: We conclude that these changes in PTH, Vit-D, TSH, osteocalcin and NTX levels maybe have a role in the pathophysiology of BRONJ. But the data need to be confirmed by future studies.

Antiresorptive Agents and Anti-Angiogenesis Drugs in the Development of Osteonecrosis of the Jaw.

Medication-related osteonecrosis of the jaw (MRONJ) is a condition of exposed bone in the maxillofacial region, which occurs among subjects treated with antiresorptive agents or anti-angiogenesis drugs, despite the lack of a history of head or neck radiation treatment. Although there are still many points to be clarified about the mechanism of MRONJ, it is possible to hypothesize a common pathogenetic mechanism for two different classes of drugs: antiresorptive and anti-angiogenetic drugs. These drugs can inhibit angiogenesis by interfering with endothelial cell proliferation and survival, leading to loss of blood vessels and avascular necrosis. This hypothesis could be of immediate translational interest. Targeting the anti-angiogenetic effect of the antiresorptive agents could provide a new possibility for the prevention of treatment of MRONJ.

Biomarkers to predict the onset of biphosphonate-related osteonecrosis of the jaw: A systematic review.

BACKGROUND: The goal of this paper was to identify available biomarkers to predict the onset of biphosphonate-related osteonecrosis of the jaw (BRONJ). MATERIAL AND METHODS: Case-control studies comparing the different concentrations of a series of molecules detected in serum and urine as matrices of BRONJ affected patients vs. non-affected were included. PRISMA guidelines for systematic reviews were used for the present paper. Two reviewers independently screened electronic databases (Medline, Web of science, and The Cochrane Library) and performed hand searches. Risk of bias assessment of selected studies was performed by the Newcastle-Ottawa Scale. This study is registered as PROSPERO CRD42017078149. RESULTS: From a total of 601 identified studies, 7 (4 articles with high methodological quality and 3 with medium) articles were included. They investigate 2623 patients, of whom 91 (3.47%) developed BRONJ. A total of 7 biomarkers were identified and classified into 3 groups: bone turnover, angiogenesis and endocrine markers. Conflicting results were found in relation to most biomarkers. CONCLUSIONS: The present review suggests that no useful markers are currently available to evaluate BRONJ risk. Nevertheless, the present paper indicates that a paradigm shift from bone turnover biomarkers to angiogenesis and endocrine markers could shed light on this search.

Altered microRNA expression profile in the peripheral lymphoid compartment of multiple myeloma patients with bisphosphonate-induced osteonecrosis of the jaw.

Bisphosphonates are formidable inhibitors of osteoclast-mediated bone resorption employed for therapy of multiple myeloma (MM) subjects with osteolytic lesions. Osteonecrosis of the jaw (ONJ) is an uncommon drug-induced adverse event of these agents. MicroRNAs (miRNAs) are a group of small, noncoding RNAs nucleotides, which are essential post-transcriptional controllers of gene expression. They have a central role in the normal bone development. The goal of our study was to investigate 18 miRNAs, whose targets were previously validated and described in MM subjects without ONJ, in peripheral lymphocytes of MM subjects with bisphosphonate-induced ONJ. Utilizing reverse transcription quantitative polymerase chain reaction, we evaluated miRNAs in five healthy subjects and in five MM patients with ONJ. Our experimental data revealed that a diverse miRNA signature for ONJ subjects emerged with respect to control subjects. Using the filter for in silico analysis, among the 18 miRNAs, we recognized 14 dysregulated miRNAs. All these miRNAs were significantly over-expressed in patients vs controls (MIR-16-1, MIR-21, MIR-23A, MIR-28, MIR-101-1, MIR-124-1, MIR-129, MIR-139, MIR-145, MIR-149, MIR-202, MIR-221, MIR-424, MIR-520). Among them, six were strongly upregulated (fourfold upregulated and more). These miRNAs target numerous pathways and genes implicated in calcium ion binding, bone resorption, mineralization of bone matrix, and differentiation and maintenance of bone tissue. A modified microRNA expression profile after zoledronate therapy could participate to the onset of ONJ. Targeting these miRNAs could provide a new opportunity for the prevention or treatment of ONJ.

Circulating microRNA Panel as a Novel Biomarker to Diagnose Bisphosphonate-Related Osteonecrosis of the Jaw.

There is no defined biomarker for BRONJ diagnosis with satisfactory performance in clinic. In this study, we established the BRONJ model and selected 7 microRNAs as candidate for BRONJ diagnosis from microRNA microarray reported by other research. Dysregulated microRNAs during BRONJ were detected and validated in two independent animal experiments using serum samples. In the first part, serum miR-21, miR-23a and miR-145 were significantly altered in between BRONJ and control group. And an Indice was constructed as -0.032+(0.154×miR-21)+(0.145×miR-23a)+(-0.700×miR-145) using logistic regression model to improve diagnostic performance. The performance of Indice to differentiate BRONJ subjects from control group was analyzed as AUC of 0.82 (95% CI, 0.72-0.92) or 0.85 (95% CI, 0.73-0.97) in the first or second part. Moreover, the predictive performance of Indice to discriminate BRONJ-1w and BRONJ-4w from control group was displayed as AUC of 0.65 (95% CI, 0.47-0.84) or 0.75 (95% CI, 0.60-0.91), which was better than individual circulating microRNAs. In addition, the expressions of candidate microRNAs were validated in human samples. Consequently, we investigated a combined Indice constructed with circulating microRNAs for BRONJ diagnosis and prediction.

Cross-Sectional Study of four Serological Bone Turnover Markers for the Risk Assessment of Medication-Related Osteonecrosis of the Jaw.

BACKGROUND: Despite the benefits related to the use of bisphosphonates and denosumab, medication-related osteonecrosis of the jaw (MRONJ) is a serious complication. The purpose of this study was to investigate the utility of 4 biochemical markers including serum c-terminal telopeptide cross-link of type I collagen (s-CTX), serum osteocalcin (s-OC), serum parathormon (s-PTH), and serum bone-specific alkaline phosphatase (s-BAP) as useful clinical tools to help assess the risk for MRONJ prior to invasive oral surgery. MATERIALS AND METHODS: Twenty patients diagnosed with MRONJ and 20 controls who have been on antiresorptive therapies with no occurrence of MRONJ were included in this 2-arm cross-sectional study. The s-CTX, s-OC, s-PTH, and s-BAP values were measured. Mann-Whitney U test compared the s-CTX, s-OC, s-PTH, and s-BAP values of the MRONJ group and the controls (P < 0.05). RESULTS: Lower values were observed in the MRONJ group compared with the control group for s-CTX (130.00 pg/mL versus 230.0 pg/mL; P = 0.12) and for s-OC (10.6 ng/mL versus 14.80 ng/mL; P = 0.051) both without significance and for s-BAP (0.23 µkat/L versus 0.31 µkat/L; P = 0.002) with significance. By contrast, the median s-PTH value of the MRONJ group was higher (30.65 ng/L versus 25.50 ng/L; P = 0.89), but without significance. CONCLUSIONS: The evaluation of the 4 biochemical markers showed that only the value of s-BAP was significantly decreased in the MRONJ patients compared with the controls. Presently, because of the lack of evidence, a routine check prior to oral surgery for the risk assessment of MRONJ cannot be recommended.

Serum levels of RANKL and OPG, and the RANKL/OPG ratio in bisphosphonate-related osteonecrosis of the jaw: Are they useful biomarkers for the advanced stages of osteonecrosis?

BACKGROUND: We determined whether serum levels of Receptor Activator for Nuclear Factor κ B Ligand (RANKL), Osteoprotegerin (OPG), and the RANKL/OPG ratio could be useful biomarkers for the severity of oral lesions in bisphosphonate-related osteonecrosis of the jaw (BRONJ). MATERIAL AND METHODS: A case-control study in which Group 1 consisted of 41 patients with BRONJ due to intravenous bisphosphonates, and Group 2 consisted of 44 healthy control cases. The plasma levels of RANKL and OPG were analyzed by an ELISA assay. The OPG/RANKL ratio was also calculated. We determined if the mean serum values differed among the different stages of BRONJ. RESULTS: Serum levels of RANKL were lower in Group 1 than in Group 2 (p =0.01), and serum levels of OPG were higher in patients with BRONJ than in the controls (p =0.006). The ratio of RANKL/OPG was greater in the controls than in Group 1 (p >0.01). There were no significant differences in the serum levels of RANKL and OPG among the different stages of osteonecrosis (p >0.05). CONCLUSIONS: Serum levels of RANKL and OPG, and the RANKL/OPG ratio were not valuable biomarkers for determining the severity of oral lesions in patients with BRONJ.

Serum Markers of Bone Turnover and Angiogenesis in Patients With Bisphosphonate-Related Osteonecrosis of the Jaw After Discontinuation of Long-Term Intravenous Bisphosphonate Therapy.

PURPOSE: To analyze serum markers of bone turnover, angiogenesis, endocrine function, and inflammation in patients with bisphosphonate-related osteonecrosis of the jaw (BRONJ) who discontinued long-term intravenous bisphosphonate (BP) therapy. PATIENTS AND METHODS: Serum samples were obtained from 25 BRONJ patients who had discontinued long-term intravenous BP therapy for an average of 11.4 ± 8.7 months and 48 non-BRONJ controls who continued receiving intravenous BP therapy. Samples were analyzed for total alkaline phosphatase, bone-specific alkaline phosphatase, osteocalcin, C-telopeptide, vascular endothelial growth factor, triiodothyronine, thyroxine, thyroid-stimulating hormone, 25-hydroxyvitamin D, and C-reactive protein. RESULTS: The mean number of BP infusions was significantly higher in BRONJ patients compared with controls (38.4 ± 26.3 infusions vs 18.8 ± 7.2 infusions, P < .0001); however, the duration of BP therapy was not significantly different between the groups (P = .23). Overall, there were no significant differences in any of the markers between BRONJ patients and controls (all P values ≥ .16). In a subgroup analysis that matched BRONJ patients and controls according to mean age and number of BP infusions (10 BRONJ patients and 48 controls), log10 vascular endothelial growth factor (2.9 ± 0.4 pg/mL vs 2.4 ± 0.4 pg/mL, P < .001) and C-reactive protein (34 ± 26 mg/L vs 13 ± 8 mg/L, P < .01) levels were significantly higher in BRONJ patients compared with controls. Within BRONJ patients, none of the serum markers were correlated with duration of BP discontinuation. CONCLUSIONS: Levels of bone turnover and endocrine markers in BRONJ patients who discontinue long-term intravenous BP therapy are similar to those in non-BRONJ controls receiving intravenous BP therapy. However, levels of angiogenesis and inflammation markers are higher in BRONJ patients who discontinue long-term intravenous BP therapy. The prolonged skeletal half-life of BPs may suppress bone turnover markers in BRONJ patients for several years after discontinuation of intravenous BP therapy, suggesting an extended effect on bone homeostasis.

Distinctive role of 6-month teriparatide treatment on intractable bisphosphonate-related osteonecrosis of the jaw.

UNLABELLED: The administration of teriparatide (TPTD) in conjunction with periodontal care could provide faster and more favorable clinical outcomes in previously refractory bisphosphonate-related osteonecrosis of the jaws (BRONJ) cases compared to conventional dental care, combination of surgery and antimicrobial treatment. We also found that underlying vitamin D levels might influence the response to TPTD treatment. INTRODUCTION: Treatment of BRONJ is quite challenging and there are no standard treatment modalities. In this retrospective, longitudinal study, we examined whether additional TPTD administration could be beneficial for the resolution of BRONJ lesions compared to conservative management, such as antimicrobial treatment with or without surgery, and also studied the factors influencing the response to TPTD. METHODS: Twenty-four cases of intractable BRONJ were included: 15 subjects were assigned to the TPTD group and the other 9 subjects, who refused TPTD administration, were assigned to the non-TPTD group. All subjects in both groups continued calcium and vitamin D supplementation and the TPTD group additionally received a daily subcutaneous injection of 20 µg TPTD for 6 months. RESULTS: While 60.0% of the non-TPTD group showed one stage of improvement in BRONJ, 40.0% of the group did not show any improvement in disease status. In the TPTD group, 62.5% of the treated subjects showed one stage of improvement and the other 37.5% demonstrated a marked improvement, including two stages of improvement or complete healing, and there was not a single case that did not improve. The clinical improvement of BRONJ was statistically better in the TPTD group after the 6-month treatment (p < 0.05). Moreover, patients with higher baseline serum 25(OH)D levels showed better clinical therapeutic outcomes with TPTD. CONCLUSIONS: We observed the beneficial effects of TPTD on BRONJ, and subjects with optimal serum vitamin D concentrations seemed to reap the maximum therapeutic effects of TPTD. A prospective, randomized, controlled trial should be needed to further evaluate the therapeutic efficacy of TPTD in the resolution of BRONJ.

Oxidative stress in bisphosphonate-related osteonecrosis of the jaws.

OBJECTIVES: To analyze whether oxidative stress (OS) changes are present in patients with bisphosphonate-related osteonecrosis of the jaw (BRONJ) versus controls. MATERIALS AND METHODS: Oxidative stress was analyzed in serum and unstimulated saliva of three groups: Group 1 consisted of 24 patients who had been treated with intravenous bisphosphonates (ivBPs) and developed BRONJ, group 2 consisted of 20 patients who had received ivBPs and did not develop BRONJ, and group 3 comprised 17 control subjects. Reduced glutathione (GSH), malondialdehyde (MDA), oxidized glutathione (GSSG), and 8-oxo-7,8-dihydro-2-deoxyguanosine (8-oxo-dG) levels, as well as the GSSG/GSH ratio, were measured. RESULTS: Mean serum and saliva levels of MDA, GSSG, and 8-oxo-dG and the GSSG/GSH ratio were significantly higher in patients with BRONJ than in controls. We found no significant difference in OS according to BRONJ stage, sex, or location in the jaws. Logistic regression analysis revealed that the GSSG/GSH ratio was a significant factor predicting the development of BRONJ (P = 0.01). CONCLUSIONS: Oxidative stress was detected in patients with BRONJ, and the GSSG/GSH ratio was the most significant OS variable found; it was a significant factor predicting the development of BRONJ.

Interleukin-6 concentration changes in plasma and saliva in bisphosphonate-related osteonecrosis of the jaws.

AIM: To determine the plasma and saliva levels of IL-6 in patients with bisphosphonate-related osteonecrosis of the jaws (BRONJ) and to investigate whether there is a correlation between more advanced stages of BRONJ and levels of IL-6. MATERIAL AND METHODS: We studied three groups: group 1 consisted of 30 patients with BRONJ due to intravenous bisphosphonates (ivBP), group 2 consisted of 25 patients treated with ivBP but without BRONJ, and group 3 consisted of 15 healthy controls. In each case, we assayed plasma and saliva IL-6 samples using an ELISA test. RESULTS: Significantly, higher IL-6 values were found in both saliva and plasma in group 1 vs groups 2 and 3 (P < 0.01). Group 1 showed no differences in plasma or saliva IL-6 according to patient gender (P > 0.05), type of tumor, BRONJ location, etiology of BRONJ, or disease stage (P > 0.05). We found higher plasma and saliva IL-6 values in the more advances stages of BRONJ, although the differences were not statistically significant. CONCLUSIONS: Plasma and saliva IL-6 values were higher in our patients with BRONJ than in controls and therefore might be a useful tool for monitoring the severity of BRONJ.

Experimental investigation of relationship between trauma and bisphosphonate-related osteonecrosis.

BACKGROUND: Bisphosphonate (BP)-related osteonecrosis of the jaw (BRONJ) disease is rare, but there are serious side-effects of BP therapy in patients. In some patients, surgery is needed and could not be cured. A standard test is not available showing the risk of jaw osteonecrosis in routine use. The measurement of serum C-terminal telopeptide (CTX) levels has been used in diseases of BRONJ resorption and antiresorptive therapy. AIM: This paper is aimed at investigating the relationship between traumatic procedures and presence of BP-related osteonecrosis. MATERIALS AND METHODS: Thirty male Wistar albino rats with weighing 200 ± 20 g were used for the experimental procedures. Rats were randomly divided into three groups each containing 10 rats as follows: Group 1 (traumatic extraction group), Group 2 (atraumatic extraction group), and Group 3 (control group). All groups, zoledronic acid (ZA) (0.3 mg/kg/week) [1] was diluted with physiological saline and given subcutaneously for 2 months. After the 2 months, Group 1 was subjected to traumatic extraction of right first lower molars, and Group 2 was subjected to atraumatic extractions of the right first lower molars. Group 3 was subjected to no extractions as a control group. Animals were euthanized 32 days after tooth extractions, and the ZA administration protocol was maintained until the animals' death. After sacrifice, blood samples were collected for C-terminal cross-linking telopeptide of type I collagen (CTX-1) levels, clinical and radiological findings were recorded. RESULTS: The bone resorption marker CTX-1 showed a significant difference among the groups. CTX-1 was measured significantly higher in blood samples of Group 2 (4.15 ± 0.34; P = 0.001) than Group 1 (3.77 ± 0.34; P = 0.0001). No, statistically significant changes were found between Groups 1 and 2 as for clinical and radiological assessment. CONCLUSION: This study provides preliminary observations for the development of an animal model of BRONJ. Although clinical and radiological findings were not relevant, serum CTX values are reliable biochemical markers for predicting BRONJ and also atraumatic surgical procedures are important to prevent BRONJ.

Weekly teriparatide injections successfully treated advanced bisphosphonate-related osteonecrosis of the jaws.

This study investigated whether weekly teriparatide (TPTD) injections are as effective as daily teriparatide injections for the treatment of stage 3 bisphosphonate-related osteonecrosis of the jaws (BRONJ) and compared serum markers of bone turnover between the two treatment regimens. Daily TPTD treatment has recently been reported to be effective for BRONJ, but there are no reports describing the effectiveness of weekly TPTD injections. We report two patients with stage 3 BRONJ. One patient was successfully treated with weekly TPTD injections and the other with daily TPTD injections. Changes in the levels of serum N-telopeptide of type I collagen (s-NTX) and serum N-terminal propeptide of type I collagen (P1NP) were studied. Two patients with stage 3 BRONJ that was refractory to conservative treatment were treated with TPTD. Their medical records were reviewed and the patients were interviewed. There was complete mucosal coverage of the intraoral defects after 3 months of TPTD treatment in both patients. Progressive bone regeneration in an area of mandibular fracture was identified after 4 months of treatment. The s-NTX level increased slightly in both patients. This is the first report of successful treatment of stage 3 BRONJ with weekly TPTD injections. Either daily or weekly TPTD injections may effectively treat stage 3 BRONJ and should be considered before or perhaps even in lieu of undertaking major resection and reconstruction.

Oral health risk factors for bisphosphonate-associated jaw osteonecrosis.

PURPOSE: To investigate the role of oral health, including periodontitis, as a risk factor for bisphosphonate-associated jaw osteonecrosis (ONJ). MATERIALS AND METHODS: This cross-sectional study compared cases with an ONJ history to controls. All had a history of bisphosphonate treatment for malignancy. Participants underwent oral examination, gingival crevicular fluid (GCF) sampling, and phlebotomy. Serum was analyzed for biochemical parameters, bone markers, and immunoglobulin G titers against 4 periodontitis-associated bacteria. Cytokine levels were determined in GCF using a multiplex assay. RESULTS: Caries development was comparable between groups. Periodontitis was significantly associated with ONJ using the US National Center for Health Statistics periodontitis definition (P = .002), at least 1 site with a probing depth of at least 4 mm (P = .003), and the percentage of sites per participant with a probing depth of 4 to 5 mm (P = .044). Immunoglobulin G titer against Porphyromonas gingivalis and GCF interleukin-1ß level were also significantly associated with ONJ (P = .018 and P = .044, respectively). CONCLUSION: In participants with a history of bisphosphonate treatment for malignancy, periodontitis was associated with ONJ when measured using clinical parameters, serum immunoglobulin G titers against P gingivalis, and GCF interleukin-1ß levels, suggesting that periodontitis and associated bacteria are potentially important in ONJ pathophysiology.

C-terminal cross-linking telopeptide as a serologic marker for bisphosphonate-related osteonecrosis of the jaw: review of 2 cases.

With the increasing use of the bisphosphonate class of drugs, dental professionals are encountering more cases of bisphosphonate-related osteonecrosis of the jaw (BRONJ). The C-terminal cross-linking telopeptide (CTX) assay is a serologic test to predict the risk of BRONJ. This paper examines the effectiveness of CTX as a biochemical marker for BRONJ and its utility to the dentist in establishing appropriate treatment plans for patients with a history of bisphosphonate use. Alternative means of assessing the risk of BRONJ are discussed, and 2 case vignettes are presented to demonstrate dental treatment planning for patients with a history of bisphosphonate use, in the context of specific CTX results.

Evaluation of serum biomarkers IL-17 and CTX for BRONJ: a pilot clinical case-control study.

A serious complication of bisphosphonate (BP) therapy is BP-related osteonecrosis of the jaw (BRONJ). Currently, no biomarkers exist to identify patients at risk. We evaluated whether interleukin-17 and C-telopeptide correlate with BRONJ development. We conducted a case-control study using patients with a history of BP therapy. Quantitative enzyme-linked immunosorbent assay and Student's t-test were done. Both markers were significantly higher in BRONJ, suggesting altered immune responses and bone remodeling may play roles in BRONJ development.

Short-term teriparatide therapy as an adjunctive modality for bisphosphonate-related osteonecrosis of the jaws.

UNLABELLED: To review the effect of teriparatide as an adjunctive modality for bisphosphonate-related osteonecrosis of the jaws (BRONJ), we describe a series of cases of teriparatide therapy for the treatment of BRONJ and serial changes of serum osteoclacin (s-OC) and serum C-terminal telopeptide cross-link of type I collagen (s-CTX). INTRODUCTION: Management of BRONJ is quite challenging and the currently recommended modalities for BRONJ are still suboptimal. For the improvement of bony remodeling, some clinicians advocated bisphosphonate holiday although validity of this drug holiday has been debated so far. Recently, the use of teriparatide was introduced in several cases, but the number of the publication is limited and mostly anecdotal so far. METHOD: Bisphosphonate was suspended and teriparatide was given to six patients diagnosed with BRONJ by single bone specialist. Medical record review and interviews were carried out. S-CTX and s-OC were measured at the baseline, 2 months and 3 months later teriparatide therapy. The outcome of the treatment and the change of biochemical markers were compared. RESULT: In all six patients, s-OC values were significantly elevated within 2 months after teriparatide treatment and the BRONJ lesions were healed. S-CTX values were also elevated in four patients, whereas those of the rest two patients stayed within minimal change. The change was marginally significant at 3 months. CONCLUSION: In terms of the multifactorial etiology of BRONJ, bone formation suppression was noticed in the patients. Based upon this finding, the short-term use of teriparatide might be beneficial to the resolution of BRONJ lesions by improving suppressed bone remodeling.

Serum N-telopeptide and bone-specific alkaline phosphatase levels in patients with osteonecrosis of the jaw receiving bisphosphonates for bone metastases.

PURPOSE: Oversuppression of bone turnover can be a critical factor in the pathogenesis of osteonecrosis of the jaw (ONJ). We investigated N-telopeptide of type I collagen (NTX) and bone-specific alkaline phosphatase (BAP) as potential predictors of ONJ onset. PATIENTS AND METHODS: Patients with ONJ and available stored serum were identified retrospectively from the institutional databases. Four approximate points were examined: point of ONJ diagnosis and 12, 6, and 1 month before the diagnosis. NTX and BAP were measured using enzyme-linked immunosorbent assays and examined as possible predictors of ONJ. RESULTS: From March 1998 to September 2009, we identified 122 patients with ONJ. Of these, 56 (46%) had one or more serum samples available. Overall, 55 patients (98%) received bisphosphonates. Using the exact dates, no obvious patterns in either NTX or BAP were noted. Similarly, using the ordinal points, no evidence of suppression of NTX or BAP over time was seen. The consecutive median values were as follows: The median NTX values were 8.0 nmol/L (range 3.8 to 32.9) at 12 months before ONJ; 9.5 nmol/L (range 4.7 to 42.7) at 6 months; 9.5 nmol/L (range 4.5 to 24.6) at 1 month, and 10.4 nmol/L (range 4.4 to 32.5) at the ONJ diagnosis. The median BAP values were BAP 18.0 U/L (range 7.0 to 74) at 12 months before ONJ; 18.0 U/L (range 4.0 to 134) at 6 months; 14.0 U/L (range 4.0 to 132) at 1 month, and 18.0 U/L (range 0.7 to 375) at the ONJ diagnosis. Only 2 patients (4%) had NTX and 17 (30%) had BAP below the normal range at the ONJ diagnosis. CONCLUSIONS: In the present large retrospective study, no trends were seen in the NTX and BAP levels before the ONJ diagnosis.

Osteonecrosis development by tooth extraction in zoledronate treated mice is inhibited by active vitamin D analogues, anti-inflammatory agents or antibiotics.

Invasive dental treatment such as tooth extraction following treatment with strong anti-bone resorptive agents, including bisphosphonates and denosumab, reportedly promotes osteonecrosis of the jaw (ONJ) at the extraction site, but strategies to prevent ONJ remain unclear. Here we show that in mice, administration of either active vitamin D analogues, antibiotics or anti-inflammatory agents can prevent ONJ development induced by tooth extraction during treatment with the bisphosphonate zoledronate. Specifically, tooth extraction during treatment with zoledronate induced osteonecrosis in mice, but administration of either 1,25(OH)2D3 or ED71, both active vitamin D analogues, significantly antagonized osteonecrosis development, even under continuous zoledronate treatment. 1,25(OH)2D3 or ED71 administration also significantly inhibited osteocyte apoptosis induced by tooth extraction and bisphosphonate treatment. Administration of either active vitamin D analogue significantly inhibited elevation of serum inflammatory cytokine levels in mice in response to injection of lipopolysaccharide, an infection mimetic. Furthermore, administration of either anti-inflammatory or antibiotic reagents significantly blocked ONJ development following tooth extraction and zoledronate treatment. These findings suggest that administration of active vitamin D, anti-inflammatory agents or antibiotics could prevent ONJ development induced by tooth extraction in patients treated with zoledronate.