Bisphosphonate-related osteonecrosis of the jaws (Bronj)

Microarchitecture of medication-related osteonecrosis of the jaw (MRONJ); a retrospective micro-CT and morphometric analysis

Medication-related osteonecrosis of the jaw (MRONJ) is a severe side effect of antiresorptive (AR) drugs such as bisphosphonates (BP) and denosumab (Dmab). Although several risk factors are described, the etiology of MRONJ is still not fully elucidated. Bone-strengthening is the primary aim of antiresorptive therapy; however, overly increased bone mass and microcrack accumulation are also discussed in MRONJ etiologies. The aim of this study is to evaluate the microarchitecture of jaw bones with micro-computed tomography (micro-CT) in AR-treated patients with or without MRONJ. Human jaw bone samples of AR-treated patients were separated into 11 groups by AR treatment bisphosphonate (BP), denosumab (Dmab), both (M) and control groups. Subgroups were divided according to the clinical localization as AR-exposed vital jaw bone (BP_exp, Dmab_exp, M_exp), osteonecrosis-margin of a sequestrum (BPO_mar, DmabO_mar, MO_mar) and osteonecrosis-sequestrum (BPO_seq, DmabO_seq, MO_seq). Healthy jaw bone (C_HB) and osteoporotic jaw bone (C_OP) represent control groups. Samples underwent retrospective micro-CT and morphometric analysis in representative units by bone volume fraction (BV/TV), bone surface density (BS/BV), trabecular thickness (Tr.Th.), trabecular number (Tr.N.), trabecular space (Tr.Sp.), Euler characteristic for bone connectivity, bone mineral density (BMD) and tissue mineral density (TMD). A total of 141 samples from 78 patients were analyzed. BV/TV of M_exp group (mean: 0.46 ± 0.27) was significantly higher than in the C_OP group (mean: 0.14 ± 0.05; p = 0.0053). Tr.Th. differed significantly between the BP_exp group (mean: 0.32 ± 0.15) and the M_exp group (mean: 0.57 ± 0.20; p = 0.0452) as well as between the BPO_seq group (mean: 0.25 ± 0.10) and the MO_seq group (mean: 0.39 ± 0.18; p = 0.0417). Signs of trabecular thickening and unorganized trabecular microarchitecture from AR-exposed- to sequestrum groups, were analyzed in 3D reconstructions. However, BS/BV, Tr.N., and Tr.Sp. showed no significant differences. Euler characteristic of the BPO_seq group (median: 7.46) doubled compared to that of the BP_exp group (median: 14.97; p = 0.0064). Mineralization parameters BMD and TMD were similar in all groups. Findings show evidence of enhanced bone mass and suspect microarchitecture in some AR-treated jaw bone compared to osteoporotic jaw bone. Despite increased bone mass, some MRONJ samples showed decreased trabecular connectivity by Euler characteristic compared to AR-treated jaw bone. These samples may indicate extensive ossification and ineffective bone mass with superficially higher bone mass without existing or even reduced mechanical stability, indicated by connectivity loss. This result might also suggest a high risk to microcrack accumulation. At some point, possibly some kind of over-ossification could lead to under-nourishment and microarchitectural weakness, creating instability, subsequently increasing vulnerability to MRONJ.

Osteonecrosis of the jaw associated with imatinib therapy in myeloproliferative neoplasm: a rare case report

Medication-related osteonecrosis of the jaw (MRONJ) is a relatively infrequent but very well-known adverse effect of bisphosphonates. This rare complication of bisphosphonates is rarest with the use of certain drugs. Tyrosine kinase inhibitors (TKIs), particularly used in renal cell carcinoma or gastrointestinal tumors as a chemotherapeutic agent, can precipitate this particular medical condition of bone when it is associated with either radiation or bisphosphonates, though, monodrug therapy with TKIs rarely causes MRONJ. This article describes a rare case of necrosis of the jawbone in a patient with a myeloproliferative neoplasm who was receiving the TKI imatinib and had no history of bisphosphonate or radiation therapy to head and neck region.

Dentists' knowledge about medication-related osteonecrosis of the jaw and its management

Objectives

To assess the knowledge of dentists regarding medication-related osteonecrosis of the jaw (MRONJ).

Methods

In this cross-sectional study, 74 dentists from governmental hospitals in Riyadh (Dental University Hospital in King Saud University, Military Hospital, National Guard Hospital), Jeddah (King Abdulaziz University Hospital, Ministry of Health Hospital), and the Eastern region of Saudi Arabia (Ministry of Health Hospitals in Dammam and Al-Ahsa) completed a two-part questionnaire. The first part gathered demographic data, such as sex and specialty. The second part included questions about bisphosphonate drugs and their indications; the identification of patients at risk of MRONJ; other medications associated with jaw necrosis; as well as the definition of MRONJ and its clinical features, risk factors, and preventive methods.

Results

Of the participating dentists, 60.8% knew about MRONJ, but only 35.1% were able to define it correctly. Most (79.7%) had never encountered MRONJ patients. Only 18.9% knew of the relationship between the risk of MRONJ in osteoporotic patients and long-term (>4 years) use of oral bisphosphonates or intravenous zoledronate, while 68.9% were unaware, and others answered incorrectly. Most participants did not know of MRONJ-predisposing medications, and 59.5% cited radiotherapy as the cause. Most participants identified dentoalveolar surgery as a major local factor, and the mandible as a common anatomic location.

Conclusion

Dentists at the surveyed institutions had poor knowledge of MRONJ, although their knowledge of preventive measures was good. There is an urgent need for the optimization of educational programs pertaining to MRONJ, and its related dental management considerations.

Clinical significance

Dentists in the surveyed institutions in Kingdom of Saudi Arabia have poor knowledge of MRONJ management; thus, greater effort should be taken to educate undergraduate and postgraduate students regarding this pathology.

Allogeneic Bone Marrow Mesenchymal Stem Cell Transplantation in Tooth Extractions Sites Ameliorates the Incidence of Osteonecrotic Jaw-Like Lesions in Zoledronic Acid-Treated Rats

Medication-related osteonecrosis of the jaw (MRONJ) is defined as the exposed necrotic bone involving the maxillofacial structures in bisphosphonate treated patients, and the pathophysiology of this disease remains unclear. The aim of this study was to assess the effects of the allogeneic transplantation of bone marrow-derived mesenchymal stem cells (BM-MSCs) in a model of Wistar mice with induced MRONJ disease. BM-MSCs from five male Wistar rats were characterized and cultured on β-tricalcium phosphate (β-TCP) granules. Thirty female Wistar rats were injected intraperitoneally with zoledronic acid and afterwards upper jaw molars were extracted. The animals were randomized to receive: Group 1: 1 × 10⁶ BM-MSCs/β-TCP construct in the alveolar socket; and Group 2: Saline solution/β-TCP construct. A clinical and histological analysis was performed. Nested polymerase chain reaction (PCR) was assessed to verify the presence of transplanted male rat cells in the female recipient jaws. Clinical and histological findings evidenced that none of the animals in Group 1 exhibited uncovered sockets or bone exposure associated to MRONJ, whereas we detected 33% of MRONJ cases in Group 2. In addition, male rat cells were detected in the maxillae site four weeks after transplantation in the BM-MSCs-group. Allogeneic BM-MSCs in extractions sites ameliorates MRONJ incidence in zoledronic acid-treated rats compared to non-MSC treatments.

Effects of anti-osteoporosis drugs against dexamethasone-induced osteoporosis-like phenotype using a zebrafish scale-regeneration model

There are several animal models of glucocorticoid-induced osteoporosis (GIOP), but each requires a long time to evaluate drug effects. Zebrafish scales are classified as dermal bone and potentially represent a convenient animal model of GIOP because they rapidly regenerate following their removal. We clarified that dexamethasone-treated regenerating scales showed malformations, decreased size and circularity. Anti-osteoporosis drugs rescued the scale malformation phenotype eight-days following the removal of scales. Hence, the dexamethasone-induced regenerating scale malformation model may be a useful animal model for discovering drugs to treat GIOP.

Pharmacoepidemiology and clinical characteristics of medication-related osteonecrosis of the jaw

Background

The aim of this study was to investigate clinical and pharmacoepidemiologic characteristics of medication-related osteonecrosis of the jaw.

Methods

The study population is comprised of 86patients who were diagnosed with ONJ at Ewha Womans University Mokdong Hospital from 2008 to 2015. Factors for epidemiologic evaluation were gender, age, location of lesion, and clinical history. The types of bisphosphonates, duration of intake, and the amount of accumulated dose were evaluated for therapeutic response. Clinical symptoms and radiographic images were utilized for the assessment of prognosis.

Results

Among the 86 patients, five were male, whereas 81 were female with mean age of 73.98 (range 45-97). Location of the lesion was in the mandible for 58 patients and maxilla in 25 patients. Three patients had both mandible and maxilla affected. This shows that the mandible is more prone to the formation of ONJ lesions compared to the maxilla. ONJ occurred in 38 cases after extraction, nine cases after implant surgery, six cases were denture use, and spontaneously in 33 cases. Seventy-six patients were taking other drugs aside from drugs indicated for osteoporosis. Most of these patients were diagnosed as osteoporosis, rheumatic arthritis, multiple myeloma, or had a history of cancer therapy. Higher weighted total accumulation doses were significantly associated with poorer prognosis (P < 0.05).

Conclusion

Dose, duration, route, and relative potency of bisphosphonates are significantly associated with treatment prognosis of osteonecrosis of the jaw.

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.

Key words:Biphosphonate, jaw, osteonecrosis, osteoporosis.

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.

Synergistic Phytochemicals Fail to Protect Against Ovariectomy Induced Bone Loss in Rats

Menopause induces a loss of bone as a result of estrogen deficiency. Despite pharmaceutical options for the treatment of osteopenia and osteoporosis, many aging women use dietary supplements with estrogenic activity to prevent bone loss and other menopausal-related symptoms. Such supplements are yet to be tested for efficacy against a Food and Drug Administration (FDA) approved medication for menopausal bone loss such as zoledronic acid (ZA). The postmenopausal rat model was used to investigate the efficacy of various synergistic phytochemical blends mixed into the diet for 16 weeks. Retired-breeder, Fischer 344 rats were randomly assigned to sham or ovariectomy surgery and 4 treatment groups: ZA; genistein supplementation; and a low dose and high dose blend of genistein, resveratrol, and quercetin. Ovariectomy resulted in a loss of both trabecular and cortical bone which was prevented with ZA. The phytochemical blends tested were unable to reverse these losses. Despite the lack of effectiveness in preventing bone loss, a significant dose-response trend was observed in the phytochemical-rich diets in bone adipocyte number compared to ovariectomized control rats. Data from this study indicate that estrogenic phytochemicals are not as efficacious as ZA in preventing menopausal-related bone loss but may have beneficial effects on bone marrow adiposity in rats.

Observational study of the bisphosphonate-related osteonecrosis of jaws

Introduction

The bisphosphonate-related osteonecrosis of the jaw was first referred to in 2003. Bisphosphonates action is focused on the osteoclasts. The drastic inhibition of the osteoclastic function is harmful for the jaws which are the only bones of the human skeleton in relative contact with the external environment. The adverse effects of the bisphosphonate-related therapy include the pathology for which they are prescribed, the atypical fractures in pathological bone.

Method

The aim of this research was to analyze the risk factors and the treatment methods in case of osteonecrosis of the jaws. To achieve these goals, the author analyzed the observation sheets of the patients admitted to the Oral and Maxillofacial Surgery Clinic during the period 2010-2015. The inclusion criteria were as follows: treatment with bisphosphonates, current or previous; the lesions of the mucous gingiva of the maxillaries followed by exposed necrotic bone, older than 8 weeks, with no tendency of healing; specific radiological image showing extended osteolysis with diffuse outline or radiopacity surrounded by radio-transparence, representing the necrotic bone sequestered; no metastasis in the necrotic maxillary bone; patient with no medical background of cervical-facial radiations. The patients who met these criteria were admitted in the study after signing the informed consent. Afterwards, the information found in the notes of the observational sheet (anamnesis, general examination and the imagistic investigation, treatment, postoperative recovery, prescription, postoperative recommendations) were gathered and submitted for statistic analysis.

Results

Of the 20 patients in total, 13 were women and 7 men, of ages ranging from 43 to 83. The most numerous cases were registered in the seventh age decade. All patients included in the study had lesions of the gingival maxillary mucosal areas with exposure of the subjacent necrotic bone. 60% of them were under intravenous treatment with zoledronic acid (Zometa®). A single patient was under oral treatment with bisphosphonates. 19 of these 20 patients developed osteonecrosis following a dental extraction while one case was due to the instability of the mandibular mobile prosthesis. 61% of the patients included in the study developed a necrotic process in the mandibular bone, 80% of the localizations were in the posterior area. As first intention, the choice of treatment was represented by local lavages with antiseptic solutions, general antibiotics and sequestrectomy. Of these patients, a third had relapsed and needed radical surgery treatment.

Conclusions

Prevention of the bisphosphonate-related osteonecrosis of the jaw represents the best method of treatment. The development of bone sequesters damages the volume of the maxillary bone as such, reducing the chances for prosthetic functional rehabilitation of the dento-maxillary system. An increase in the quality of life by oral restoration of these patients may represent a challenge.

[Research progress on bisphosphonate-related osteonecrosis of the jaws]

Bisphosphonates (BPs), as potent drugs inhibiting bone resorption, have been widely used for treatment of several diseases. In recent years, dentists and oral and maxillofacial surgeons reported continuously increasing cases of bisphosphonate-related osteonecrosis of the jaws (BRONJ). This disease is clinically characterized by exposed bones, formation of sequestrum, pain, and halitosis. Provided that pathogenesis of BRONJ is unclear, effective treatments for this disease are currently unavailable. Thus, prevention plays an important role in the management of BRONJ. This review summarizes research progress on pathogenesis, risk factors, clinical characteristics, treatment, and prevention of this condition.

Analysis of different therapeutic protocols for osteonecrosis of the jaw associated with oral and intravenous bisphosphonates

Introduction

Chemotherapy-associated osteonecrosis of the jaw caused by bisphosphonates is an exposure of necrotic bone with more than eight weeks of evolution that is attributable to bisphosphonates and no prior radiation therapy. Its etiopathogenesis remains unknown, although there are two hypotheses that may explain it: the drug’s mechanism of action, and the risk factors that can lead to osteonecrosis. There is a wide range of treatment options for managing chemotherapy-associated osteonecrosis of the jaw, from conservative treatments to surgical procedures of varying levels of invasiveness, which are sometimes supplemented with adjuvant therapies.

Objectives

The objective of this article is to group the therapeutic options for osteonecrosis of the jaw (ONJ) into seven different protocols and to evaluate their effectiveness in relation to stage of ONJ.

Material and Methods

A literature review was carried out in PubMed following the PRISMA criteria. A total of 47 were collected after compiling a series of variables that define ONJ, applied treatments, and the clinical results obtained.

Results and Discussion

The 47 articles selected have a low to average estimated risk of bias and are of moderate to good quality. According to the data obtained, Protocol 3 (conservative treatment, clinical and radiological follow-up, minimally invasive surgical treatment, and adjuvant therapies) is the most favorable approach for ONJ lesions caused by oral bisphosphonates. For lesions caused by intravenous bisphosphonates, Protocol 2 (conservative treatment, clinical and radiological follow-up, minimally invasive surgical treatment, and no adjuvant therapies) is the best approach. When comparing the different stages of ONJ, Protocol 1 (conservative treatment, clinical and radiological follow-up) promotes better healing of Stage 1 ONJ lesions caused by orally administered bisphosphonates, and Protocol 3 is recommended for Stage II. For ONJ lesions attributable to intravenous bisphosphonates, Protocol 7 (conservative treatment, clinical and radiological follow-up, and adjuvant therapies) provides the best results in Stage 0; in Stages I, II, and III, Protocol 1 gives better results.

Key words:Bisphosphonates, bronj, therapeutic protocol, clinical result.

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.

Prevalence of Medication-Related Osteonecrosis of the Jaw in Patients with Breast Cancer, Prostate Cancer, and Multiple Myeloma

Medication-related osteonecrosis of the jaw is a known side-effect of antiresorptive therapy in patients with malignant diseases. Nevertheless, the exact pathogenesis is still unknown and published prevalences show a significant range. The aim of the presented paper was to assess the prevalence of osteonecrosis (ONJ) in breast cancer, prostate cancer, and multiple myeloma patients receiving parenteral antiresorptive therapy. For this reason a PubMed search was performed and 69 matching articles comprising 29,437 patients were included in the analysis. Nine-hundred fifty-one cases of jaw necrosis were described. The overall ONJ-prevalence was 2.09% in the breast cancer group, 3.8% in the prostate cancer group, and 5.16% for multiple myeloma patients.

Surgical management of bisphosphonate-related osteonecrosis of the jaws: literature review

PURPOSE

Surgical management of bisphosphonate-related osteonecrosis of the jaws (BRONJ) has been performed in an attempt to increase healing rates of the affected cases. This literature review aimed to identify clinical studies of surgical management of bisphosphonate-related osteonecrosis of the jaws (BRONJ) in order to assess their surgical treatment modalities, outcome and the follow-up.

METHODS

A search in the PubMed (Medline) database using specific terms and/or phrases as "bisphosphonate-related osteonecrosis" or "jaw osteonecrosis", and "surgical treatment" or "surgical management" was conducted in order to identify clinical trials and cases of surgical treatment of BRONJ. The review search covered the time period from 2004 to 2014. All studies identified in the search were selected according to the inclusion criteria. Relevant information was recorded according to the following items: author, year, number of patients, BRONJ clinical stage, surgical treatment modality, clinical success, and follow-up.

RESULTS

The initial database search yielded 345 titles. After filtering, 67 abstracts were selected culminating in 67 full text articles. A variety of surgical approach was found in this review: debridement, sequestrectomy bone resection, and bone reconstruction. Adjunctive therapies included hyperbaric oxygen, laser therapy, growth factors, and ozone.

CONCLUSION

Although there are many indexed studies about BRONJ, well-documented reports concerning surgical therapeutically techniques are scarce, resulting from a lack of well-established protocols. Considerable differences were found regarding sample size, surgical treatment modalities and outcomes. Clinical studies with larger number of patients and longer follow-up are required to provide best information for each surgical treatment modality and its outcomes.

Free flap reconstruction for patients with bisphosphonate related osteonecrosis of the jaws after mandibulectomy

INTRODUCTION

Bisphosphonate related osteonecrosis of the jaws (BRONJ) is a recognised unwanted effect of these drugs which affect bone remodelling. Treatment options range from conservative approaches through local bone debridement to free flap reconstruction following segmental resection. This current study aims to evaluate clinical outcomes after microvascular tissue transfer in BRONJ patients.

MATERIAL AND METHODS

A total of 212 BRONJ patients were included in this prospective investigation. Those who met defined inclusion criteria and received a surgical intervention were reviewed regularly during a follow-up period of at least 6 months.

RESULTS

Twenty-five patients (11.8%) received free flap reconstructions. A mean of 2.12 local debridements were performed before microvascular tissue transfer. A mean of 29.25% showed BRONJ recurrence after minimalist surgical intervention, compared to significantly less in patients after resection and free flap reconstruction. The postoperative fistula rate was significantly higher in patients, who received mucoperiosteal flaps.

DISCUSSION

This study underlines the importance and effectiveness radical resection and free flap reconstruction in the complex and challenging surgical treatment of BRONJ patients in a large patient cohort study. Nevertheless, all patients received radical intervention after failure of minimally invasive treatment. An individualized analysis and planning is necessary to identify appropriate patients for free flap reconstructions.

Orthobiologics in the augmentation of osteoporotic fractures

Many orthobiologic adjuvants are available and widely utilized for general skeletal restoration. Their use for the specific task of osteoporotic fracture augmentation is less well recognized. Common conductive materials are reviewed for their value in this patient population including the large group of allograft adjuvants categorically known as the demineralized bone matrices (DBMs). Another large group of alloplastic materials is also examined-the calcium phosphate and sulfate ceramics. Both of these materials, when used for the proper indications, demonstrate efficacy for these patients. The inductive properties of bone morphogenic proteins (BMPs) and platelet concentrates show no clear advantages for this group of patients. Systemic agents including bisphosphonates, receptor activator of nuclear factor κβ ligand (RANKL) inhibitors, and parathyroid hormone augmentation all demonstrate positive effects with this fracture cohort. Newer modalities, such as trace ion bioceramic augmentation, are also reviewed for their positive effects on osteoporotic fracture healing.

Systematic review on the incidence of bisphosphonate related osteonecrosis of the jaw in children diagnosed with osteogenesis imperfecta

Objectives

To conduct a systematic review of epidemiological literature to determine the incidence of bisphosphonate related osteonecrosis of the jaw occurring either spontaneously or after dental surgery, in children and adolescents diagnosed with osteogenesis imperfecta.

Material and Methods

MEDLINE, HMIC and EMBASE were used to search for English-language articles published from 1946 - 2013. Inclusion criteria consisted of population based studies of children and adolescents (24 years and younger) diagnosed with osteogenesis imperfecta, only studies which included a dental examination, and patients treated with intravenous bisphosphonates were included. Articles were excluded if patients had any other co-morbidity which could affect osteonecrosis of the jaw, and those which treated patients with oral bisphosphonates only.

Results

Five studies consisting of four retrospective cohort studies and one case series were identified. Study populations ranged from 15 to 278 patients and number of subjects with osteogenesis imperfecta ranged from 15 to 221. Mean duration of intravenous bisphosphonate use ranged from 4.5 to 6.8 years. All patients were clinically examined and no patients were found to have osteonecrosis of the jaw.

Conclusions

There is no evidence to support hypothesis of causal relationship between bisphosphonates and osteonecrosis of the jaw in children and adolescents with osteogenesis imperfecta. More prospective studies on bisphosphonate use in osteogenesis imperfecta needs to be carried out.

The outcome after surgical therapy of bisphosphonate-associated osteonecrosis of the jaw--results of a clinical case series with an average follow-up of 20 months

OBJECTIVES

The present case series evaluates the success rate of osteotomy and primary wound closure in patients with bisphosphonate-associated osteonecrosis of the jaw (BRONJ).

MATERIALS AND METHODS

Eighty patients suffering from BRONJ were included in the study. All patients received intravenous bisphosphonate therapy and underwent osteotomy and primary wound closure according to a standardised protocol. After discharge, the patients were reviewed on a regular basis over an average time period of 20 months.

RESULTS

During follow-up in 11 patients, a recurrence of BRONJ occurred in the former operation field. Seventeen patients died due to their underlying disease. The success rate of osteotomy and primary wound closure in the treatment of BRONJ was calculated at 84.2 % 20 months after surgery. The results showed non-significant difference concerning the outcome of surgery in the different clinical stages of BRONJ.

CONCLUSIONS

In accordance with previous studies, stage-independent osteotomy and primary wound closure combined with antibiotics shall be deemed a viable treatment option in patients suffering from BRONJ.

CLINICAL RELEVANCE

With a high success rate, osteotomy in combination with primary wound closure seems to be a viable alternative to more conservative protocols in the treatment of BRONJ.