Predicting risk for bisphosphonate-related osteonecrosis of the jaws: CTX versus radiographic markers

Precursor Radiographic Findings in Patients With Medication-Related Osteonecrosis of the Jaw

BACKGROUND

Oral surgical treatment, such as tooth extraction, has been identified as a risk factor for the onset of medication-related osteonecrosis of the jaw (MRONJ). However, MRONJ may already be latent, and its manifestation may be triggered by extraction.

PURPOSE

The purpose of this study was to examine the association between pre-extraction imaging and MRONJ.

STUDY DESIGN, SETTING, SAMPLE

We performed a multicenter case-control analysis of patients receiving antiresorptive agents (ARAs) who underwent extraction between 2012 and 2016. We enrolled patients who had undergone tooth extraction in the setting of ARA exposure.

PREDICTOR VARIABLES

The predictor variables comprised preoperative radiographic findings associated with MRONJ stage 0. These findings included alveolar bone loss, thickening or obscuring of the periodontal ligament, and osteosclerosis involving the alveolar bone. They were coded as present or absent before tooth extraction.

MAIN OUTCOME VARIABLE

The primary outcome variable was MRONJ status coded as present or absent.

COVARIATES

Sex, age, underlying diseases necessitating the administration of ARA, the type of ARA used, corticosteroid use, extraction region, and wound closure were analyzed.

ANALYSES

Mann-Whitney U test, χ2 test, Fisher's exact test for univariate analysis, and multiple logistic regression analysis were performed. P values < .05 were significant.

RESULTS

The subjects consisted of 26 patients and 110 controls (male: 8/36, female: 18/74). The mean ages of the MRONJ group and the control group were 77.0 ± 11.9 and 63.0 ± 15.8, respectively (P value = .001). The prevalence of osteosclerosis was significantly higher in the MRONJ group than in the control group (14/72, 53.9%/29.3%, P < .01). Multivariate analysis identified osteosclerosis (odds ratio: 8.4, 95% confidence interval: 2.133.9, P < .01) as a significant independent predictor associated with the development of MRONJ after extraction.

CONCLUSION AND RELEVANCE

These findings suggest that a precursor to MRONJ is highly likely to be present in patients with osteosclerosis at the time of extraction. The majority of patients who developed MRONJ after extraction had imaging findings that suggested infection in the surrounding alveolar bone.

Influence of antiresorptive/antiangiogenic therapy on changes in periodontal and oral tissue structures: a histomorphometrical analysis in rats

OBJECTIVE

The objective of this study was to investigate the influence of various antiresorptive and antiangiogenic medications on morphological changes in periodontal and oral tissue structures.

MATERIALS AND METHODS

Fifty-five Wistar rats randomly received dual application (i.e., at baseline and after 12-weeks) one of the following medications: (1) amino-bisphosphonate [zoledronate (Zo)], (2) RANKL inhibitor [denosumab (De)], (3) antiangiogenic [bevacizumab (Be)], (4) Zo + Be, (5) De + Be or (6) no medication [Control (Co)]. Periodontal and oral tissue biopsies were obtained at 17 (n = 21 animals, Phase 1, (De = 3, De + Be = 3, Zo = 5, Be = 3, Zo + Be = 2, Co = 5) and 29 (n = 34 animals, (De = 8, De + Be = 6, Zo = 2, Be = 7, Zo + Be = 4, Co = 7, Phase 2) weeks after the second drug application. The following outcomes were histomorphometrically assessed: periodontal space width in the coronal (PLS-C, mm) and apical sections (PLS- A), number of empty alveolar bone lacunae in the coronal, apical sections and at the apex at respective tooth sites (EL - C, EL- A, EL- Ap), mucosal thickness at edentulous alveolar ridge areas (MT, mm), and, when present, associated areas of inflammatory cell infiltrates (ICI, mm2).

RESULTS

Comparable mean PLS-C, PLS-A, ET-A, ET-C, ET-Ap, and MT values were observed in all experimental groups after Phases 1 and 2. The presence of ICI was identified in 3 animals in the Co group (Phase 1: 1, Phase 2: 2), and 17 animals in the test groups (Phase 1: 4; Phase 2: 14). The estimated ICI surface area was significantly higher in the Zo + Be group, followed by the Zo and Be groups compared to that measured in the Co group. The time (i.e., Phases 1 and 2) was not found to be a predictor for the extent of the ICI area. In all groups, the EL-C, EL-A, and EL-Ap values were significantly higher after Phase 2 compared to those assessed after Phase 1. The MT values were significantly reduced in all groups after Phase 2 compared to those measured after Phase 1.

CONCLUSIONS

The present evaluation was not able to find any morphological effects of different antiresorptive and antiangiogenic medications on periodontal and oral tissue structures. The presence of inflammatory cell infiltrates was more frequently observed in the animals administered with antiresorptive and antiangiogenic medications as well as combinations thereof.

CLINICAL RELEVANCE

Administration of antiresorptive and antiangiogenic medications may be capable of inducing inflammatory reactions in periodontal tissues.

Prevalence of dental alterations in patients under bisphosphonates therapy: a systematic review

This systematic review aimed to estimate the prevalence and describe dentoalveolar lesions associated with bisphosphonates therapy. A systematic review of the literature was conducted using the following databases: PubMed, Embase, Cochrane, CINAHL, Scopus, Web of Science, Lilacs, SciElo, and Grey Literature. Quality of individual studies analysis was performed by using Newcastle-Ottawa Scale. Certainty of cumulative evidence was achieved by applying Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. The software R Statistics version 4.0.5 (The R Foundation) was used for proportion estimations per study and corresponding confidence intervals were estimated through the Clopper-Pearson method. Four articles were included for the qualitative synthesis. Two studies were considered of good quality, one of fair, and one of poor quality. A total of 231 patients were encompassed. Widening of the periodontal ligament space (22.2-39.7%), periradicular radiolucencies (20-22.9%), and pulp calcifications (33.3-69.2%) were the most frequent alterations. Certainty of evidence was rated as very low. Based on limited evidence, this systematic review reports a variety of dentoalveolar alterations in patients under bisphosphonate therapy. These features might impact on dental clinical practice. However, the level of evidence is considered very low due to important limitations.

Organic Bone Matrix Component Type I and V Collagen Are Not Destructed in Bisphosphonate-Associated Osteonecrosis of the Jaws

Background and objectives: The investigation of the pathophysiology behind medication-related osteonecrosis (MRONJ) of the jaw mostly focuses on alterations in osteoclast and osteoblast cell activity, but changes in the organic and inorganic bone matrix have rarely been studied. The aim of this study was to investigate whether collagen, the main organic component of extracellular bone matrix, is destructed in osteonecrosis of the jaw secondary to antiresorptive medication. Material and methods: Bone samples of patients with MRONJ (n = 15, control group n = 3) were demineralized, and collagen fragments were separated from intact collagen pellets by ultrafiltration. The quantification of mature collagen cross-links hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP) in pellets and ultrafiltrates was performed by high-performance liquid chromatography (HPLC). The detection of hydroxyproline (Hyp) was carried out using a spectrophotometric assay. In addition, collagen chains were analyzed by sodium dodecylsulfate-polyacrylamide gel (SDS-PAGE). Results: The results revealed significantly higher concentrations of HP, LP and Hyp in pellet samples. In addition, there were no significant differences between samples from MRONJ patients and those of the control group. These results were paralleled by SDS- PAGE. Conclusion: These findings suggest that MRONJ does not involve the destruction of type I and V collagen molecules, in contrast to previously reported destruction by osteoradionecrosis.

American Association of Oral and Maxillofacial Surgeons' Position Paper on Medication-Related Osteonecrosis of the Jaws-2022 Update

Strategies for management of patients with, or at risk for, medication-related osteonecrosis of the jaws (MRONJ) - formerly referred to as bisphosphonate-related osteonecrosis of the jaws (BRONJ)-were set forth in the American Association of Oral and Maxillofacial Surgeons (AAOMS) position papers in 2007, 2009 and 2014. The position papers were developed by a committee appointed by the AAOMS Board of Trustees and comprising clinicians with extensive experience in caring for these patients, as well as clinical and basic science researchers. The knowledge base and experience in addressing MRONJ continues to evolve and expand, necessitating modifications and refinements to the previous position papers. Three members of the AAOMS Committee on Oral, Head, and Neck Oncologic and Reconstructive Surgery (COHNORS) and three authors of the 2014 position paper were appointed to serve as a working group to analyze the current literature and revise the guidance as indicated to reflect current knowledge in this field. This update contains revisions to diagnosis and management strategies and highlights the current research status. AAOMS maintains that it is vitally important for this information to be disseminated to other relevant healthcare professionals and organizations.

Medication Related Osteonecrosis of the Jaw: 2021 Position Statement of the Korean Society for Bone and Mineral Research and the Korean Association of Oral and Maxillofacial Surgeons

Antiresorptives are the most widely prescribed drugs for the treatment of osteoporosis. They are also used in malignant bone metastases, multiple myeloma, and Paget's disease, and provide therapeutic efficacy on those diseases. However, it was reported that the occurrence of osteonecrosis of the jaw (ONJ) could be related to antiresorptive exposures, and there have been many cases regarding this issue. Therefore, a clearer definition and treatment guidelines were needed for this disease. The American Society for Bone and Mineral Research and the Amnerican Association of Oral and Maxillofacial Surgeons reported statements on bisphosphonate-related ONJ (BRONJ), and a revised version was recently presented. In the revised edition, the diagnosis BRONJ was changed to medication-related ONJ (MRONJ), which reflects consideration of the fact that ONJ also occurs for denosumab, a bone resorption inhibitor of the receptor activator of the nuclear factor-κB ligand antibody family, and bevacizumab, an anti-angiogenesis inhibitor. The Korean Society for Bone and Mineral Research and the Korean Association of Oral and Maxillofacial Surgeons had collectively formed a task force for the preparation of an official statement on MRONJ based on a previous position paper in 2015. The task force reviewed current knowledge and coordinated dental and medical opinions to propose the guideline customized for the local Korean situation.

Preclinical models of medication-related osteonecrosis of the jaw (MRONJ)

Medication-related osteonecrosis of the jaw (MRONJ) is a potentially severe adverse event affecting patients with cancer and patients with osteoporosis who have been treated with powerful antiresorptives (pARs) or angiogenesis inhibitors (AgIs). pARs, including nitrogen-containing bisphosphonates (N-BPs; e.g., zoledronic acid, alendronate) and anti-RANKL antibodies (e.g., denosumab), are used to manage bone metastases in patients with cancer or to prevent fragility fractures in patients with osteoporosis. Though significant advances have been made in understanding MRONJ, its pathophysiology is still not fully elucidated. Multiple species have been used in preclinical MRONJ research, including the rat, mouse, rice rat, rabbit, dog, sheep, and pig. Animal research has contributed immensely to advancing the MRONJ field, particularly, but not limited to, in developing models and investigating risk factors that were first observed in humans. MRONJ models have been developed using clinically relevant doses of systemic risk factors, like N-BPs, anti-RANKL antibodies, or AgIs. Specific local oral risk factors first noted in humans, including tooth extraction and inflammatory dental disease (e.g., periodontitis, periapical infection, etc.), were then added. Research in rodents, particularly the rat, and, to some extent, the mouse, across multiple laboratories, has contributed to establishing multiple relevant and complementary preclinical models. Models in larger species produced accurate clinical and histopathologic outcomes suggesting a potential role for confirming specific crucial findings from rodent research. We view the current state of animal models for MRONJ as good. The rodent models are now reliable enough to produce large numbers of MRONJ cases that could be applied in experiments testing treatment modalities. The course of MRONJ, including stage 0 MRONJ, is characterized well enough that basic studies of the molecular or enzyme-level findings in different MRONJ stages are possible. This review provides a current overview of the existing models of MRONJ, their more significant features and findings, and important instances of their application in preclinical research.

Emerging therapies with potential risks of medicine-related osteonecrosis of the jaw: a review of the literature

In the past, osteonecrosis of the jaw (ONJ) was generally reported with bisphosphonate drugs; hence, the term BRONJ (bisphosphonate-related osteonecrosis of the jaw) was initially proposed. This was followed by the term ARONJ (antiresorptive osteonecrosis of the jaw). More recently, other novel medications such as vascular endothelial growth factor (VEGF) inhibitors, tyrosine kinase inhibitors and humanised antibodies that affect osteoclastic action have been reported to initiate ONJ in several cases. For this reason, in 2014, the American Association of Oral and Maxillofacial Surgeons (AAOMS) changed the term to MRONJ - medication-related osteonecrosis of the jaw. The review primarily focuses on ONJ associated with emerging therapies for the management of bone disorders. This article sheds some light on the risk factors that predispose dental patients to the development of osteonecrosis, the mechanisms of drug therapies associated with MRONJ, and potential treatment and management regimes for MRONJ patients. The current review noted that the incidence and associated risk of MRONJ is significant with the new therapeutic agents discussed. Therefore, for optimised patient care, pharmacovigilance with the new medications is essential for dental professionals.

Bisphosphonates as Supplement to Dental Treatment: A Network Meta-Analysis

The objective of this study was to assess clinical measurements related to the effectiveness of bisphosphonate (BP) administration as a supplement to conventional dental treatment in patients free of bone-related diseases using a network meta-analysis. Only randomized controlled trials (RCTs) were included that provided dental clinical measurements on human patients treated with BPs with or without similar untreated controls or treated with placebo. Information sources included a systematic search of 17 electronic databases up to August 2020, complemented by manual searches. Risk of bias assessment was performed with the revised Cochrane risk of bias tool for randomized trials (RoB 2.0). Extracted measurements were pooled according to time of evaluation. The random-effects model by DerSimonian and Laird was used to calculate mean differences (MDs) and the respective 95% confidence intervals (CIs). Seven RCTs were included in the network meta-analysis, assessing 391 subjects reporting on periodontal treatment effects after 2 to 12 mo of BP administration. BP treatment was associated with significant improvement of most clinical measurements, compared with BP-naive controls. According to the network ranking, alendronate was more efficient in improvement of probing depth and clinical attachment gain when compared to zoledronate or alendronate/risedronate. Similarly, the local application of alendronate as a gel was more effective than the oral administration. A long-term analysis of the pharmaceutical effects was not possible due to insufficient data. The current review, performed according to existing guidelines, included only RCTs and, through appropriate statistical analyses, provided precise estimates for most assessed outcomes. However, no adverse effects or long-term treatment results were analyzed due to inadequate pertinent data. BP administration seems to be beneficial in the short term for the treatment of periodontal diseases, mainly through controlling periodontal inflammation.

A nitrogen-containing bisphosphonate inhibits osteoblast attachment and impairs bone healing in bone-compatible scaffold

Compromised osteoblast attachment on hydroxyapatite could be involved in the development of bone healing failure. We developed a bone-compatible scaffold that mimics bone structure with sub-micron hydroxyapatite (HA) surfaces, so that we could evaluate the effects of nitrogen-containing bisphosphonate (N-BP) on osteoblast behavior and bone healing. Human osteoblasts were seeded onto the bone-compatible scaffold with or without N-BP, and cell attachment and spreading behavior were evaluated 4 and 24 h after seeding. Then, mineralization was evaluated at 7 and 14 days. The osteoconductive activity of the scaffold was evaluated by implantation for 3 and 6 weeks into a rat cranial bone defect. The numbers of osteoblasts and their diameters were significantly less in N-BP-binding scaffolds than in untreated scaffolds at 4 and 24 h. Mineralization were also significantly less in the N-BP-binding scaffolds than in controls at 7 and 14 days. In vivo study revealed bone formation in N-BP-binding scaffolds was significantly less than in untreated scaffolds at 3 and 6 weeks. These results suggest that N-BP-binding to HA inhibited osteoblast attachment and spreading, thereby compromising bone healing process in the injured bone defect site.

Metabolomic profiling reveals salivary hypotaurine as a potential early detection marker for medication-related osteonecrosis of the jaw

Medication-related osteonecrosis of the jaw (MRONJ) is a rare but serious adverse event of bone-modifying agents used to prevent bone complications in cancer patients with bone metastasis. Currently, early treatment is the only way to prevent further progression, as the pathogenesis of MRONJ has not yet been elucidated, and a standard treatment has not been established. The aim of this study was to identify a marker for early detection marker of MRONJ by exploring substances in saliva specific to MRONJ at an early stage. We collected salivary samples from 17 patients with MRONJ and conducted metabolomic analyses using capillary electrophoresis mass spectrometry for non-targeted analysis of hydrophilic metabolites. In the screening cohort, we compared the saliva of patients with stage ≥1 advanced MRONJ (n = 9) with that of controls without MRONJ before chemotherapy (n = 9). The top 5 most elevated salivary metabolites were histamine, 3-(4-hydroxyphenyl)propionate, malonate, carnosine, and hypotaurine. In the validation cohort, we analyzed additional patients with stage ≥1 advanced MRONJ (n = 8) and controls without MRONJ after chemotherapy (n = 9), confirming a significant 2.28-fold elevation in the salivary concentration of hypotaurine. These results revealed elevated salivary hypotaurine concentration as a potential marker for the early detection of MRONJ.

Treatment of Bisphosphonate-Related Osteonecrosis of the Jaw With Plasma Rich in Growth Factors After Dental Implant Surgery: A Case Report

Oral bisphosphonates are commonly used to improve bone density in patients who suffer from a variety of pathologies. However, they have also been known to cause bisphosphonate-related osteonecrosis of the jaws (BRONJ). The aim of this clinical case presentation is to (1) determine whether the currently recommended length of time that oral bisphosphonates should be discontinued, before performing dental implant surgery, is sufficient to prevent BRONJ and (2) to describe an alternative treatment for BRONJ. A 65-year-old female patient developed BRONJ after receiving mandibular dental implants 5 months after discontinuing alendronic acid (Fosamax). The BRONJ was treated by surgical osteotomy and plasma rich in growth factors (PRGF), and the patient was followed up with biweekly examinations, which included 0.2% chlorhexidine mouthwashes and removal of any remaining necrotic bone. The dental implants were loaded 41 weeks after surgery and followed up with periapical radiographs and implant stability quotient measurements at 3, 6, 12, and 24 months postloading. Although the Association of Oral and Maxillofacial Surgeons protocols for suspension of presurgical oral bisphosphonates were followed, this patient still developed BRONJ after implant surgery. While a multitude of treatments have been described in the literature, there is not enough scientific evidence to support any one treatment. Based on this clinical case, it can be concluded that the potential adverse effects of oral bisphosphonates on the jaws could be greater than expected and that treatment with PRGF produces promising results, although more long-term studies are necessary to confirm these findings.

Serum C-terminal cross-linking telopeptide level as a predictive biomarker of osteonecrosis after dentoalveolar surgery in patients receiving bisphosphonate therapy: Systematic review and meta-analysis

BACKGROUND

The authors' aim in this systematic review was to evaluate the validity of using preoperative serum C-terminal cross-linking telopeptide (CTX) levels as a predictive factor of increased risk of developing medication-related osteonecrosis of the jaw (MRONJ) in patients receiving bisphosphonate (BP) therapy who underwent invasive dental procedures.

TYPES OF STUDIES REVIEWED

The authors searched PubMed, MEDLINE, and Web of Science and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. The authors conducted a meta-analysis on the risk ratio. The authors used the methodological index for nonrandomized studies and Quality Appraisal of Reliability Studies checklist to assess quality.

RESULTS

The authors included 18 clinical trials involving 2,301 patients. Most patients received alendronate or risedronate for an average of 62.14 months. The average serum CTX level in patients who received BP before surgery was 198.25 picograms per milliliter. Meta-analysis results showed that the cutoff in CTX level (150 pg/mL) was not predictive of MRONJ risk. The sensitivity of CTX values lower than 150 pg/mL was 34.26%, and the specificity was 77.08%.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

The use of CTX levels to diagnose MRONJ risk after dental procedures in patients receiving BP is not justified. The cutoff of 150 pg/mL in serum CTX levels is not predictive of MRONJ. Further studies are needed to develop other reliable biomarkers.

Therapeutic effects of caffeic acid phenethyl ester on alveolar bone loss in rats with endotoxin-induced periodontitis

Background/purpose

Caffeic acid phenethyl ester (CAPE) is an antioxidant which is decreases the bone resorption and enhances the bone healing. The aim of this study was to investigate the effects of administering systemic CAPE on alveolar bone loss in rats with experimental periodontitis.

Materials and methods

Thirty male Sprague Dawley rats were divided into three groups: control, endotoxin-induced periodontitis (EP), and EP treated with CAPE (EP-CAPE). Endotoxin was injected into the gingiva of test rats on days 1, 3, and 5, whereas saline was injected into the control rats. The EP-CAPE group received 10 mmol/kg/day CAPE intraperitoneally for 28 consecutive days. Saline was given in the control and EP groups in the same manner. At the end of the study, intracardiac blood samples were obtained, and the rats were sacrificed. Alveolar bone loss was analyzed with histometric measurements. The oxidative stress index (OSI) was used to evaluate the oxidative stress. The receptor activator of the nuclear factor kappa B ligand (RANKL) level was analyzed stereologically.

Results

CAPE administration significantly decreased the serum OSI and interleukin-1β levels. Alveolar bone loss was statistically higher in the EP group compared with the EP-CAPE group (P < 0.05). Immunohistochemical analyses of the RANKL were significantly lower in the EP-CAPE group than in the EP group (P < 0.05).

Conclusion

This experimental study revealed that CAPE administration significantly prevented alveolar bone loss and stimulated periodontal tissue healing.

Effects of ultraviolet treatment and alendronate immersion on osteoblast-like cells and human gingival fibroblasts cultured on titanium surfaces

In this study, we evaluated the effects of ultraviolet (UV) treatment and alendronate (ALN) immersion on the proliferation and differentiation of MG-63 osteoblast-like cells and human gingival fibroblasts (HGFs) cultured on titanium surfaces. MG-63 cells were used for sandblasted, large grit, and acid-etched (SLA) titanium surfaces, and HGFs were used for machined (MA) titanium surfaces. SLA and MA specimens were subdivided into four groups (n = 12) according to the combination of surface treatments (UV treatment and/or ALN immersion) applied. After culturing MG-63 cells and HGFs on titanium discs, cellular morphology, proliferation, and differentiation were evaluated. The results revealed that UV treatment of titanium surfaces did not alter the proliferation of MG-63 cells; however, HGF differentiation and adhesion were increased in response to UV treatment. In contrast, ALN immersion of titanium discs reduced MG-63 cell proliferation and changed HGFs into a more atrophic form. Simultaneous application of UV treatment and ALN immersion induced greater differentiation of MG-63 cells. Within the limitations of this cellular level study, simultaneous application of UV treatment and ALN immersion of titanium surfaces was shown to improve the osseointegration of titanium implants; in addition, UV treatment may be used to enhance mucosal sealing of titanium abutments.

Non-Viral Delivery System and Targeted Bone Disease Therapy

Skeletal systems provide support, movement, and protection to the human body. It can be affected by several life suffering bone disorders such as osteoporosis, osteoarthritis, and bone cancers. It is not an easy job to treat bone disorders because of avascular cartilage regions. Treatment with non-specific drug delivery must utilize high doses of systemic administration, which may result in toxicities in non-skeletal tissues and low therapeutic efficacy. Therefore, in order to overcome such limitations, developments in targeted delivery systems are urgently needed. Although the idea of a general targeted delivery system using bone targeting moieties like bisphosphonates, tetracycline, and calcium phosphates emerged a few decades ago, identification of carrier systems like viral and non-viral vectors is a recent approach. Viral vectors have high transfection efficiency but are limited by inducing immunogenicity and oncogenicity. Although non-viral vectors possess low transfection efficiency they are comparatively safe. A number of non-viral vectors including cationic lipids, cationic polymers, and cationic peptides have been developed and used for targeted delivery of DNA, RNA, and drugs to bone tissues or cells with successful consequences. Here we mainly discuss such various non-viral delivery systems with respect to their mechanisms and applications in the specific targeting of bone tissues or cells. Moreover, we discuss possible therapeutic agents that can be delivered against various bone related disorders.

Prevalence of radiographic findings on jaws exposed to antiresorptive therapy: a meta-analysis

OBJECTIVES:

Determine the prevalence of radiographic findings (RF) on both jaws among patients receiving antiresorptive bone therapy.

METHODS:

Six electronic databases and partial grey literature were searched. Data was collected based on predetermined criteria. The key features from the included studies were extracted. The MAStARI tool assessed the potential risk of bias (RoB) among the studies, while the GRADE approach determined the level of evidence.

RESULTS:

29 studies were identified and included in the qualitative analysis, totalling 1133 patients. 27 studies had sufficient data to be included in a series of meta-analysis reporting 12 types of radiographic findings, and were split in two groups based on their study design. G1 comprised descriptive observational studies and G2 analytical cross-sectional studies. Two studies presented a high RoB, 16 had a moderate RoB, and 11 had low RoB. The overall level of evidence identified was very low. The most frequent RF were mixed lytic-sclerotic areas (73.88%), followed by osteolytic changes (66.18%), osteosclerosis (65.75%), cortical bone erosion (50.83%), persisting alveolar socket (45.77%), periodontal ligament (PDL) widening (44.69%), and inferior alveolar canal (IAC) involvement (43.40%). Less frequent, but equally important, were the periosteal reaction (34.27%), lamina dura thickening (32.97%), sequestrum (29.94%), pathologic fracture (20.90%), and density confluence of cortical and cancellous bone (16.61%). 20 patients reported no signs.

CONCLUSIONS:

RF prevalence was high and mainly included mixed lytic-sclerotic areas, osteolysis, osteosclerosis, cortical bone erosion, persisting alveolar socket, PDL-widening, IAC-involvement. Due to the very low level of evidence (GRADE) caution should be exercised when considering these findings.

Radiographic bone loss and the risk of medication-related osteonecrosis of the jaw (MRONJ) in multiple myeloma patients-A retrospective case control study

Risk factors for medication-related osteonecrosis of the jaws (MRONJ) include type and duration of antiresorptive drugs, dental trauma, local anatomy, systemic underlying conditions and therapy, smoking, and the presence of periodontal disease. However, there is a lack of studies elucidating the role of periodontal disease as risk predictor. In the present study, the dental charts of 100 multiple myeloma (MM) patients and 16 MM patients who developed MRONJ were studied. Information about age, gender, smoking history, diabetes, steroid drug intake, type and duration of bisphosphonate (BP) treatments, MRONJ status, missing teeth, periapical lesions, widening of the periodontal ligament, and periodontal status was collected. The periodontal status was determined as a percentage of missing bone at the mesial and distal surfaces of each tooth. Multivariable logistic regression was performed to identify risk factors associated with MRONJ. In the selected model, using the COX analysis, categorical bone loss percentage is significantly associated with MRONJ (P = 0.009), with hazard ratio 0.042 (high vs low) and 95% CI 0.004 to 0.453. Gender, steroid, Aredia BP type, and periapical are also significant in selected model. In conclusion, advanced alveolar bone loss and missing teeth were strongly related to the occurrence of MRONJ in MM patients.

Changes in dimension of neurovascular canals in the mandible and maxilla: A radiographic finding in patients diagnosed with MRONJ

Background

The aim of this retrospective study was to compare the morphological features of neurovascular canals and foramina of patients with medication-related osteonecrosis of the jaws (MRONJ) and healthy individuals by using cone beam computed tomography (CBCT).

Material and Methods

The CBCT images of 58 patients under bisphosphonate therapy diagnosed with MRONJ and age gender- matched controls were retrospectively evaluated. The diameter of mandibular and nasopalatine canal and mandibular, mental and lingual foramina were measured on several sections of CBCT. The value of mental index (MI) and panoramic mandibular index (PMI) were also assessed.

Results

The mean value of diametric measurements for all neurovascular canals and foramina in MRONJ patients were narrower than controls. Left mandibular foramen was the most affected area (p<0.001). There were significantly difference in all measurements of mental foramen, lingual foramen and mandibular incisive canal between two groups (p<0.05). PMI of MRONJ subjects were also significantly differences in both sides (p<0.05).

Conclusions

In MRONJ patient, neurovascular canals and foramina are affected due to the alterations in bone remodeling. Therefore, the diametric measurement of neurovascular canals and assessment of MI and PMI on CBCT, is a potentially useful method for detection of early changes associated with bisphosphonate therapy and for predict areas where new necrosis may occur.

Key words:Bisphosphonate, MRONJ, CBCT, neurovascular canals, PMI.

CT imaging features of antiresorptive agent-related osteonecrosis of the jaw/medication-related osteonecrosis of the jaw

OBJECTIVES

Antiresorptive agent-related osteonecrosis of the jaw (ARONJ)/medication-related osteonecrosis of the jaw (MRONJ) include both bisphosphonate-related osteonecrosis of jaw (BRONJ) and denosumab-related osteonecrosis of jaw (DRONJ). The purpose of this study is to study radiological characteristics of ARONJ/MRONJ. These imaging features may serve as one useful aid for assessing ARONJ/MRONJ.

METHODS

CT scans of 74 Japanese patients, who were clinically diagnosed by inclusion criteria of ARONJ/MRONJ, obtained between April 1, 2011 and September 30, 2016, were evaluated. We investigated the CT imaging features of ARONJ/MRONJ, and clarified radiological differentiation between BRONJ and DRONJ, BRONJ due to oral bisphosphonate administration and due to intravenous bisphosphonate administration, BRONJ with respective kinds of medication, BRONJ with long-term administration and short-term administration, BRONJ with each clinical staging respectively. Fisher's exact test, χ² test, Student's t-test and analysis of variance were performed in the statistical analyses.

RESULTS

Unilateral maxillary sinusitis was detected in all patients with upper ARONJ/MRONJ (100%). DRONJ showed large sequestrum more frequently than BRONJ (3/4, 75 vs 3/35, 8.6%, p < 0.05). DRONJ showed periosteal reaction more frequently than BRONJ (4/10, 40 vs 7/65, 10.1%, p < 0.05). Patients of BRONJ resulting from intravenous bisphosphonate administration showed larger and more frequent buccolingual cortical bone perforations than BRONJ resulting from oral bisphosphonate administration (7/8, 87.5 vs 11/30, 36.7%, p < 0.05). There was no significant correlation between CT findings and respective kinds of medication, long/short-term administration, clinical stages of BRONJ.

CONCLUSIONS

ARONJ/MRONJ has characteristic CT image findings which could be useful for its assessment.

Detecting the earliest radiological signs of bisphosphonate-related osteonecrosis

Introduction Oral bisphosphonates are the most commonly prescribed anti-resorptive drugs used in the treatment of osteoporosis, but osteonecrosis of the jaw is a serious complication. The early diagnosis of this destructive side effect is crucial in preventing excessive bone loss, pain and infection.Objective To aid dental practitioners in the early identification of bisphosphonate-related osteonecrosis of the jaw.Method A scoping review was carried out.Data sources We searched MEDLINE via OVID, EMBASE via OVID, Dentistry and Oral Sciences Source (DOSS), Proquest Dissertation and Theses Search, to identify references that described clinical and radiological findings in medication-related osteonecrosis of the jaw (MRONJ).Data selection Nineteen references mentioned the earliest radiological changes in MRONJ with a description of the observations and were included in the analysis.Data synthesis The radiographic signs included osteosclerosis/lysis, widening of the periodontal ligament and thickening of the lamina dura and cortex. To assess the quality of original data on which recommendations had been made, these 19 studies were subjected to a quality appraisal.Conclusion Using bone exposure as a criterion for diagnosis of MRONJ, leads to delayed diagnosis and a poor response to treatment. In those patients at risk of bone exposure with MRONJ, insufficient information is present in the literature to allow the general dental practitioner to reliably identify the radiographic features indicating imminent bone exposure. A well-designed prospective study is needed.

Development of Bone Targeting Drugs

The skeletal system, comprising bones, ligaments, cartilage and their connective tissues, is critical for the structure and support of the body. Diseases that affect the skeletal system can be difficult to treat, mainly because of the avascular cartilage region. Targeting drugs to the site of action can not only increase efficacy but also reduce toxicity. Bone-targeting drugs are designed with either of two general targeting moieties, aimed at the entire skeletal system or a specific cell type. Most bone-targeting drugs utilize an affinity to hydroxyapatite, a major component of the bone matrix that includes a high concentration of positively-charged Ca²⁺. The strategies for designing such targeting moieties can involve synthetic and/or biological components including negatively-charged amino acid peptides or bisphosphonates. Efficient delivery of bone-specific drugs provides significant impact in the treatment of skeletal related disorders including infectious diseases (osteoarthritis, osteomyelitis, etc.), osteoporosis, and metabolic skeletal dysplasia. Despite recent advances, however, both delivering the drug to its target without losing activity and avoiding adverse local effects remain a challenge. In this review, we investigate the current development of bone-targeting moieties, their efficacy and limitations, and discuss future directions for the development of these specific targeted treatments.

Radiographic evidence of treatment with bisphosphonates

Bony disease is typically evident with radiographic examination. Loss of bone mass consistent with osteoporosis is evident on plain dental radiographs, and it is reasonable to expect that anti-resorptive treatment of osteoporosis would lead to changes in radiodensity of structures visible on dental radiographs. Review of a number of radiographs of patients receiving anti-resorptive (bisphosphonate) treatment appears to confirm increased radiodensity of the structures, which may have implications in risk assessment of complications following dental procedures.

Interrelationship of clinical, radiographic and haematological features in patients under bisphosphonate therapy

OBJECTIVES

To analyze the clinical, radiographic and haematological aspects of patients under bisphosphonate therapy.

METHODS

A retrospective study was conducted where the records of patients taking bisphosphonates were analyzed considering the occurrence of bisphosphonate-related osteonecrosis of the jaw (BRONJ). Evaluation included panoramic and periapical radiographies, haematological examinations and clinical features. Radiographies were analyzed determining the presence or absence of bone sclerosis, osteolysis, persisting alveolar socket, narrowing of the mandibular canal, widening of the periodontal ligament space, periradicular radiolucency, sequestrum and thickening of the lamina dura. Laboratory tests consisted of complete blood count, fasting serum glucose, erythrocyte sedimentation rate (ESR) and serum levels of calcium, phosphorus, alkaline phosphatase, parathormone (PTH) and C-terminal telopeptide of collagen I (CTX).

RESULTS

Alkaline phosphatase and ESR were significantly higher in the BRONJ group, whereas fasting serum glucose, CTX, PTH, calcium and phosphorus did not significantly differ. BRONJ showed association with smoking, tooth extraction, anaemia and leukocytosis. On radiographic analysis, persisting alveolar socket, osteolysis, bone sclerosis and narrowing of the mandibular canal were significantly more prevalent in the BRONJ group. Thickening of the lamina dura, periapical radiolucencies, widening of the periodontal ligament space and sequestrum did not significantly differ between the groups.

CONCLUSIONS

BRONJ is a multifactorial disease with high morbidity, which requires experimental studies to clarify the role of the reported risk factors and clinical radiographic signs to improve its diagnosis.

Review of common conditions associated with periodontal ligament widening

Purpose

The aim of this article is to review a group of lesions associated with periodontal ligament (PDL) widening.

Materials and Methods

An electronic search was performed using specialized databases such as Google Scholar, PubMed, PubMed Central, Science Direct, and Scopus to find relevant studies by using keywords such as “periodontium”, “periodontal ligament”, “periodontal ligament space”, “widened periodontal ligament”, and “periodontal ligament widening”.

Results

Out of nearly 200 articles, about 60 were broadly relevant to the topic. Ultimately, 47 articles closely related to the topic of interest were reviewed. When the relevant data were compiled, the following 10 entities were identified: occlusal/orthodontic trauma, periodontal disease/periodontitis, pulpo-periapical lesions, osteosarcoma, chondrosarcoma, non-Hodgkin lymphoma, progressive systemic sclerosis, radiation-induced bone defect, bisphosphonate-related osteonecrosis, and osteomyelitis.

Conclusion

Although PDL widening may be encountered by many dentists during their routine daily procedures, the clinician should consider some serious related conditions as well.

Efficacy of the C-terminal telopeptide test in predicting the development of bisphosphonate-related osteonecrosis of the jaw: a systematic review

This systematic review evaluated the efficacy of the morning fasting serum C-terminal telopeptide (CTX) test in predicting the development of bisphosphonate-related osteonecrosis of the jaw (BRONJ). A comprehensive search of studies published up to March 2016, and listed in the PubMed/MEDLINE, Web of Science, and Cochrane Library databases, was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. This review has been registered in the PROSPERO international prospective register of systematic reviews (CRD42016036717). The search identified 542 publications; eight studies were finally deemed eligible for inclusion according to the study criteria. These studies included a total 1442 patients (mean age 66.7 years). The most prescribed drug was alendronate, with osteoporosis being the most frequent indication for the prescription of bisphosphonates. Tooth extraction was the most common trigger for BRONJ. Of all patients evaluated after bisphosphonate treatment, only 24 (1.7%) developed BRONJ. All eight of the selected studies found that CTX levels were not predictive of the development of BRONJ. In conclusion, this systematic review indicates that the CTX test has no predictive value in determining the risk of osteonecrosis in patients taking bisphosphonates.

Evaluation of the predisposing factors and involved outcome of surgical treatment in bisphosphonate-related osteonecrosis of the jaw cases including bone biopsies

Objectives

This study examined the statistical relevance of whether the systemic predisposing factors affect the prognosis of surgical treatment of bisphosphonate-related osteonecrosis of the jaw (BRONJ). All cases had undergone bone biopsies to determine the characteristics of the mechanisms of BRONJ by optical microscopy.

Materials and Methods

The data included 54 BRONJ cases who underwent surgery and in whom bone biopsies were performed. The results of surgery were evaluated and the results were classified into 3 categories: normal recovery, delayed recovery, and recurrence after surgery. The medical history, such as diabetes mellitus, medication of steroids, malignancies on other sites was investigated for an evaluation of the systemic predisposing factors in relation to the prognosis. The three factors involved with the medication of bisphosphonate (BP) were the medication route, medication period, and drug holiday of BP before surgery. The serum C-terminal cross-linking telopeptide (CTX) value and presence of microorganism colony in bone biopsy specimens were also checked. Statistical analysis was then carried out to determine the relationship between these factors and the results of surgery.

Results

The group of patients suffering from diabetes and on steroids tended to show poorer results after surgery. Parenteral medication of BP made the patients have a poorer prognosis after surgery than oral medication. In contrast, the medication period and drug holiday of BP before surgery did not have significance with the results of surgery nor did the serum CTX value and presence of microorganism colony. Necrotic bone specimens in this study typically showed disappearing new bone formation around the osteocytic lacunae and destroyed Howship's lacunae.

Conclusion

Although many variables exist, this study could in part, predict the prognosis of surgical treatment of BRONJ by taking the patient's medical history.

Are there any differences in mandibular morphology of patients with bisphosphonate-related osteonecrosis of jaws?: a case-control study

OBJECTIVES:

The aim of this study was to compare the morphological differences in the mandible between patients with bisphosphonate-related osteonecrosis of the jaw (BRONJ) and healthy individuals and to detect the correlation between these parameters on panoramic radiography and CBCT.

METHODS:

The CBCT and panoramic images of patients with BRONJ (n = 32) and control groups (n = 32) were included in the study. All the comparisons were analyzed between the osteonecrosed and healthy sides of patients with BRONJ and control group. The panoramic radiographs were used to measure the values of the condyle angle, gonial angle, antegonial angle, antegonial depth, condylar height and ramal height. The mandibular cortical index (MCI) and bone quality index (BQI) were also examined on cross-sectional scans of CBCT images.

RESULTS:

There were significant differences in the MCI (p = 0.014) and BQI (p = 0.021) between the left and right side of the BRONJ group and also between the osteonecrosed side of the BRONJ and control group (p < 0.0001). No significant difference was found in other comparisons.

CONCLUSIONS:

The outcomes of the present study indicate that bisphosphonates influenced some internal morphological changes in the mandible. These changes may be a reason of BRONJ. But, these changes are not reflective of the measured values obtained using panoramic radiographs on the external morphology of the mandible.

Assessing the utility of serum C-telopeptide cross-link of type 1 collagen as a predictor of bisphosphonate-related osteonecrosis of the jaw: A systematic review and meta-analysis

BACKGROUND

The authors of this systematic review and meta-analysis assessed the utility of serum C-telopeptide cross-link of type 1 collagen (sCTX), a biomarker of bone resorption, as a predictor of the development of bisphosphonate-related osteonecrosis of the jaw (BRONJ).

TYPES OF STUDIES REVIEWED

The authors searched for studies involving adult participants, written in English, and published through January 20, 2016, using the following electronic databases: the Cochrane Library, MEDLINE via PubMed, and Web of Science. They also searched Google Scholar and the reference lists of all eligible trials and reviews. They identified 16 articles that met their inclusion criteria (9 controlled studies and 7 case series). They applied the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for systematic reviews and meta-analyses. They independently extracted data in duplicate, including the characteristics of study participants, risk factors, control groups, and outcomes. They assessed risk of bias, and they resolved any disagreements between review authors through discussion.

RESULTS

A meta-analysis with 9 controlled studies revealed no significant difference in mean sCTX values between patients with BRONJ and control participants (difference in means, -31.417; 95% confidence interval [CI], -91.560 to 28.726; P = .306). A second meta-analysis with 4 studies showed no significant difference in risk of having an sCTX value below 150 picograms per milliliter for patients with BRONJ compared with control participants (risk ratio, 1.892; 95% CI, 0.636-5.626; P = .251).

CONCLUSIONS AND PRACTICAL IMPLICATIONS

A systematic review of the literature with meta-analysis does not support the use of sCTX levels as a predictor of the development of BRONJ. Further prospective large sample studies are needed to understand the role of sCTX as a predictor for BRONJ.

Epidemiological study of alendronate-related osteonecrosis of the jaw in the southeast of Scotland

We aimed to establish the incidence of alendronate-related osteonecrosis of the jaw (ONJ) in the southeast of Scotland, and to assess the effect of corticosteroids on it. We studied a prospective case series of patients between June 2004 and March 2012 separated into steroid and non-steroid groups. There were 34 cases of alendronate-related ONJ and 78732 drug patient years (DPY) of alendronate, making the overall occurrence 43.1 cases/100000 DPY. There were 12 patients in the steroid group (mean (range) age 68.2 (48-87) years) making 42.5 cases/100000 DPY, and 22 in the non-steroid group (mean (range) age 76.2 (63-91) years) making 119.6 cases/100000 DPY. The mean (range) age at presentation of alendronate-related ONJ was significantly lower in the steroid group (68.2 (48-87) compared with 76.2 (63-91) years, p=0.019) as was the duration of exposure to alendronate before it developed (28.9 (6-120) compared with 61.3 (13-168) months, p=0.03). The overall incidence seems to be higher in the southeast of Scotland than elsewhere. Concurrent use of corticosteroids is not associated with an increased incidence of alendronate-related ONJ, but it seems to reduce the duration of exposure before it develops. Age is likely to be a confounding factor.

Medication Related Osteonecrosis of the Jaw: 2015 Position Statement of the Korean Society for Bone and Mineral Research and the Korean Association of Oral and Maxillofacial Surgeons

Bisphosphonates are the most widely prescribed drugs for the treatment of osteoporosis, and are also used in malignant bone metastases, multiple myeloma, and Paget's disease, and provide therapeutic efficacy on those diseases. However, it was reported that occurrence of osteonecrosis of the jaw (ONJ) could be related with bisphosphonate exposures, and there have been many cases regarding this issue. Therefore, a clearer definition and treatment guidelines were needed for this disease. The American Society for Bone and Mineral Research (ASBMR) and American Association of Oral and Maxillofacial Surgeons (AAOMS) reported statements on bisphosphonate-related ONJ (BRONJ), and a revised version was recently presented. In the revised edition, the diagnosis BRONJ was changed to medication-related ONJ (MRONJ), which reflects a consideration of the fact that ONJ also occurs for denosumab, a bone resorption inhibitor of the receptor activator of nuclear factor-kappa B ligand (RANKL) antibody family, and bevacizumab, an anti-angiogenesis inhibitor. In 2009, a statement on ONJ was also reported locally by a relevant organization, which has served as basis for clinical treatment in Korea. In addition to the new official stance of the AAOMS and ASBMR, with an increasing pool of ONJ clinical experience, a revised version of the 2009 local statement is needed. As such, the Korean Society for Bone and Mineral Research (KSBMR) and the Korean Association of Oral and Maxillofacial Surgeons (KAOMS) have collectively formed a committee for the preparation of an official statement on MRONJ, and have reviewed recent local and international data to propose guidelines customized for the local Korean situation.

Genetic association between VEGF polymorphisms and BRONJ in the Korean population

OBJECTIVES

The purpose of this study was to evaluate the association between vascular endothelial growth factor (VEGF) polymorphisms and bisphosphonate-related osteonecrosis of the jaw (BRONJ) in the Korean population.

SUBJECTS AND METHODS

Forty-five individuals (2 men, 43 women; mean age: 68.7 ± 12.3 years) were recruited for this study. All visited the Yonsei University Dental Hospital for surgical intervention from January 2012 to January 2013 and had a history of bisphosphonate (BP) administration (oral and/or intravenous). Patients were allocated to case (n = 26) or control (n = 19) groups according to the patients' selection criteria. Association between three VEGF single nucleotide polymorphisms (rs699947 (-2578 C>A), rs2010963 (-634 G>C) and rs3025039 (+936 C>T)) and BRONJ were investigated using multiple logistic regression analysis and Fisher's exact test where appropriate (α = 0.05).

RESULTS

The CC homozygotes of rs2010963 and rs3025039 of VEGF gene were associated with an increased risk of BRONJ (P = 0.04, 0.03, respectively). In haplotype analysis, no differences in haplotype C-C (-2578/-634) and haplotype C-C-C (-2578/-634/+936) were observed.

CONCLUSION

The CC homozygotes of rs2010963 and rs3025039 polymorphisms in the VEGF gene were associated with an increased risk of BRONJ in the Korean population. Further epidemiological cohort studies with a larger sample size would be required to confirm the suggestive correlations.

Mandibular inferior cortical bone thickness on panoramic radiographs in patients using bisphosphonates

OBJECTIVE

The goal of this study was to detect dimensional changes in the mandibular cortical bone associated with bisphosphonate (BP) use and to correlate measurements of the cortical bone with the cumulative dose of BPs.

STUDY DESIGN

Mandibular inferior cortical bone thickness (MICBT) was measured under the mental foramen on panoramic radiographs of patients with and without bisphosphonate-related osteonecrosis of the jaws (BRONJ) taking BPs and controls.

RESULTS

Patients with BRONJ had the highest mean MICBT (6.81 ± 1.35 mm), compared with patients without BRONJ taking BPs (5.44 ± 1.09 mm) and controls (4.79 ± 0.85 mm) (P < .01). Mean MICBT of patients with BRONJ was significantly higher than that of patients without BRONJ taking BPs. There was a correlation between MICBT and cumulative dose of zolendronate.

CONCLUSIONS

Measurement of MICBT on panoramic radiographs is a potentially useful tool for the detection of dimensional changes associated with BP therapy.

Salivary Biomarkers Associated With Bone Deterioration in Patients With Medication-Related Osteonecrosis of the Jaws

PURPOSE

The purpose of this study was to investigate the use of saliva as a medium for the identification of biomarkers associated with bone resorption and formation. The authors hypothesized that biomarkers, such as N-telopeptide of type I collagen (NTX) and bone-specific alkaline phosphatase (B-AP), could be identified in saliva. They further hypothesized that there would be a difference between these biomarkers in the saliva of patients with medication-relation osteonecrosis of the jaws (MRONJ) and those who have no risk factors for the development of MRONJ.

PATIENTS AND METHODS

This case-and-control study compared 2 salivary biomarkers, NTX and B-AP, in a group of patients with MRONJ and a control group. The predictor variable was the presence or absence of the disease (MRONJ or control group); the outcome variables were the levels of the 2 salivary biomarkers, NTX and B-AP. Saliva samples from 20 patients with a diagnosis of MRONJ and 14 control participants who were comparable to the study group with no history of antiresorptive medication use were collected. The saliva samples were analyzed using 2 commercially available assays for NTX and B-AP to evaluate for levels of each marker. A 2-tailed t test for 2 groups of unequal distribution was used for statistical analysis, with P values less than .05 considered statistically.

RESULTS

The 2 biomarkers, NTX and B-AP, were detected in saliva samples from the MRONJ and control groups. A statistically significant difference was found in the levels of NTX in saliva of patients with MRONJ compared with the control participants (P = .0067).

CONCLUSIONS

In this exploratory study, the 2 bone deterioration biomarkers (NTX and B-AP) were detected in saliva. There was a statistical difference in the levels of salivary NTX between patients with MRONJ and controls. Saliva evaluation could provide a novel method to detect, diagnose, stage, and potentially guide treatment decisions and monitor outcomes for patients with MRONJ in the future.

Sclerosis in bisphosphonate-related osteonecrosis of the jaws and its correlation with the clinical stages: study of 43 cases

We analysed the degree of sclerosis in the different stages of bisphosphonate-related osteonecrosis of the jaws (BRONJ) and studied the relation between the grade of sclerosis, the clinical symptoms, and the depth of lucency. We compared 43 patients with mandibular BRONJ with a control group of 40 cases with no bony lesions. The presence of sclerotic bone, cortical irregularities, radiolucency, fragmentation or sequestration, periostitis, and narrowing of the mandibular canal were studied from computed tomographic (CT) scans using the program ImageJ 1.47v (National Institute of Health, Bethesda, USA) to measure the radiolucency, width of the cortices, and degree of sclerosis. Patients with BRONJ had more severe sclerosis than controls (p<0.01). There was also a significant difference among the different stages of BRONJ, with the highest values found in stage III (p=0.02). The degree of sclerosis differed according to sex, type of bisphosphonate, and the clinical characteristics such as pain, or suppuration, but not significantly so (p>0.05). We conclude that the degree of sclerosis increases with the clinical stage of BRONJ, and is correlated with the depth of lucency.

Osteochemonecrosis: an overview

Osteonecrosis of the jaw to a certain extent has been with us for many years. But recently the advent of various medications such as bisphosphonates, VEGF inhibitors, tyrosine kinase inhibitors and humanized antibodies to osteoclastic action have resulted in thousands of cases. While the bisphosphonates continue to be the most common medication associated with osteochemonecrosis antibodies such as denosumab which irreversibly act on osteoclastic action are also being reported. This narrative review will serve as an update with a focus on some of the histopathologic features discussed and reviewed. Perhaps even more uncommonly seen in past reports a discussion of features possibly observed while grossing specimens will be discussed. At the end of this report is hoped that the pathologist will have a better understanding of the historical features, clinical settings, gross examination features as well as histopathologic features associated with osteochemonecrosis.

Effects of alendronate on the peri-implant bone in rats

OBJECTIVES

The purpose of this study was to determine the effects of alendronate on the peri-implant bone in rat maxillae with the aid of micro-computed tomographic, histologic, and biochemical analyses.

MATERIALS AND METHODS

Thirty-six male Sprague-Dawley rats were used. After extraction of the maxillary first molars, each rat was given periodic subcutaneous injections of either alendronate (alendronate group) or saline (control group). Customized implants were placed bilaterally 4 weeks after these injections. The rats were sacrificed at either 4, 8, or 12 weeks after implantation (4-, 8-, and 12-week groups, respectively; n = 6 rats per group). Microcomputed tomographic and histologic analyses were conducted for all rats. Biochemical analyses were performed at four time points for the 12-week groups.

RESULTS

There were no significant differences between the groups on microcomputed tomographic and histologic analyses. All of the measured biochemical parameters tended to decrease over time, with significant differences among some time points within each group. The serum osteocalcin level was significantly lower in the 12-week alendronate group than in the control group (P < 0.05).

CONCLUSIONS

Three approaches were utilized in evaluating the effects of alendronate. It appears serum osteocalcin levels may serve as an adjuvant marker for this purpose, although further studies are required to confirm this.

Imaging findings of bisphosphonate-related osteonecrosis of the jaws: a critical review of the quantitative studies

Objectives. This paper offers a critical review of published information on the imaging strategies used for diagnosing bisphosphonate-associated osteonecrosis of the jaw (BRONJ) in patients taking intravenous bisphosphonates, pointing at the different methodologies and results of existing literature. Methods. Electronic literature search was performed in order to identify as many quantitative studies that discussed the imaging findings of BRONJ up to February 2014. Initially, the search for articles was based on the following four types of imaging modalities for evaluating BRONJ: computed tomography, plain film radiographs, magnetic resonance imaging, and nuclear bone scanning. Results. Eleven out of the 79 initially selected articles met the inclusion criteria. Most of the selected articles were cross-sectional studies. Regarding the selected studies, 54.5% have used plain films radiographs and 54.5% were based on computed tomography findings. All of the selected studies showed a small number of patients and none of the selected studies have tested the accuracy of the imaging examination for evaluating BRONJ. Conclusions. This critical review showed a scarcity of quantitative studies that analyzed the typical imaging findings related to BRONJ. Further studies are necessary in order to analyze the role of different imaging techniques in the assessment of BRONJ.

Alendronate-associated osteonecrosis of the jaws: a review of the main topics

Bisphosphonates is a group of inorganic pyrophosphates analogues that suppress bone resorption by inducing osteoclast inactivation, being frequently used for management of diseases affecting bone metabolism, bone metastases and bone tumors. However, since 2003 many cases describing the presence of necrotic bone exposures in the jaws have been described in patients receiving these drugs, what represent a significant complication of bisphosphonates treatment. The overall incidence of bisphosphonate-related osteonecrosis of the jaws is low, ranging from 0.7% to 12%, mainly observed in those patients receiving intravenously treatment. Osteonecrosis of the jaws associated to oral bisphosphonate, particularly alendronate, has also been reported by a number of authors. Considering that alendronate is one of the most used drugs worldwide, specially for treatment of osteoporosis, a better understanding of osteonecrosis of the jaws related to its use and how to manage these patients is extremely important. Therefore, in the current manuscript the authors aim to review the most important topics related to this pathological presentation.

Key words:Bisphosphonates, alendronate, bisphosphonate-related osteonecrosis of the jaws, osteonecrosis.

Conservative surgical management of stage I bisphosphonate-related osteonecrosis of the jaw

Purpose. To report the efficacy of conservative surgical treatment for stage I bisphosphonate-related osteonecrosis of the jaw (BRONJ). Materials and Methods. This study reports the clinical outcomes of 63 patients treated for BRONJ stage I (according to Ruggiero's staging system) at the Oral Pathology and Laser-Assisted Surgery Unit of the University of Parma between January 2004 and January 2011. Surgical interventions were performed, under local analgesia, in patients unresponsive for a period of six months to noninvasive treatments such as cycles of local or systemic antibacterial therapy combined or not to low level laser therapy, ozone therapy, or Hyperbaric Oxygen Therapy. All interventions were performed after the consultation of oncologist or physician. Results. In our experience, conservative surgical treatment is associated with the highest number of BRONJ healed sites in stage I disease. Complete healing was observed in 92.6% of sites surgically treated. Conclusions. This study confirms that treatment of patients affected by minimal bone exposition, (stage I of BRONJ), through conservative surgical strategies, possibly with laser, may result in a high control of the disease in the long term.

Important aspects concerning alendronate-related osteonecrosis of the jaws: a literature review

OBJECTIVE

To conduct a literature review on sodium alendronate, focusing on osteonecrosis of the jaws, a serious potential side effect.

BACKGROUND

Sodium alendronate is a bisphosphonate that is widely used for the treatment of osteopenia, osteoporosis and Paget's disease. Like other bisphosphonates, it inhibits bone resorption by inactivating osteoclasts. Alendronate has evident benefits in the treatment of these diseases, but it is associated with jaw osteonecrosis, although less frequently compared with intravenous bisphosphonates. Therefore, some preventive measures should be taken to avoid this side effect.

MATERIAL AND METHODS

We reviewed the literature regarding the pharmacological aspects, mechanism of action, indications of use and side effects of sodium alendronate, as well as the management of patients under this therapy.

CONCLUSION

The benefits of sodium alendronate are scientifically proven, but a serious adverse effect is osteonecrosis. Therefore, it is crucial to prepare the oral cavity before bisphosphonate therapy, providing a careful dental evaluation and all needed dental treatment.