Bisphosphonate and Nonbisphosphonate-Associated Osteonecrosis of the Jaw

Maxillary Osteonecrosis Related with Herpes Zoster: A Case Report and Review of the Literature

Osteonecrosis of the jaw (ONJ) can occur through various mechanisms including radiation, medication, and viral infections such as herpes zoster. Although herpes zoster is a varicella-zoster virus infection that can affect the trigeminal nerve, it rarely causes oral complications. The author reports a rare case of herpes zoster-related ONJ, followed by a review of the relevant literature pertaining to herpes zoster-related oral complications, including ONJ. A 73-year-old woman presented with a scarred skin lesion on her left midface with an exposed alveolar bone of the left maxilla. Based on her medical records, she received a diagnosis and treatment for herpes zoster six months prior and experienced a few teeth loss in the left maxilla following a fall preceding the onset of herpes zoster. Sequestrectomy of the left maxilla was performed and ONJ was diagnosed. The operative site recovered favorably. Although unusual, several cases of localized extensive ONJ in herpes zoster-infected patients have been reported. This case illustrates the possibility of a rare occurrence of unilateral widespread osteonecrosis of the jaw (ONJ) even in the maxilla associated with herpes zoster. The exact mechanism has not been elucidated; nevertheless, surgeons should consider the possibility of oral and dental complications, including ONJ, related to a history of herpes zoster.

Can medication-related osteonecrosis of the jaw be attributed to specific microorganisms through oral microbiota analyses? A preliminary study

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) can cause significant pain and loss of aesthetics and function if not treated properly. However, diagnosis still relies on detailed intraoral examinations and imaging. Prognosis varies even among patients with similar stages or conditions of MRONJ, emphasizing the need for a deeper understanding of its complex mechanisms. Thus, this study aimed to identify the oral microbiota of patients with MRONJ.

METHODS

This single-center prospective cohort study included patients with confirmed MRONJ who visited the Department of Oral and Maxillofacial Surgery at Yonsei University Dental Hospital between 2021 and 2022. Oral swab samples were collected from the affected and unaffected sides of each patient. The composition and enumeration of the microbial communities were analyzed, and the diversity was compared to verify ecological changes in the groups using a next-generation sequencing-based 16S metagenomic analysis. A statistical analysis was performed using Wilcoxon signed-rank test with SPSS version 22, and values of P less than 0.05 were considered statistically significant.

RESULTS

The final study sample included 12 patients. The mean age was 82.67 ± 5.73 (range, 72-90) years. Changes in microbial composition were observed at different taxonomic levels (phylum, genus, and species). The identified microorganisms were commonly associated with periodontitis, gingival disease, and endodontic infection, suggesting a multifactorial etiology of MRONJ.

CONCLUSIONS

Although this study is based on a small number of cases, it shows that MRONJ is not caused by a specific microorganism but can rather be caused by a variety of factors. By addressing these findings in large-scale studies, the significance of oral microbiome in pathogenesis can be further elucidated and can facilitate the development of effective therapeutic interventions for patients with MRONJ.

Real-world study of antiresorptive-related osteonecrosis of jaw based on the US food and drug administration adverse event reporting system database

Objective: This study aims to explore the risk signals of osteonecrosis of the jaw induced by antiresorptive drugs and provide references for the clinical safety application. Method: According to the FDA's Adverse Event Reporting System (FAERS), from January 2004 to September 2021, we chose "Osteonecrosis of the jaw (10064658)" and "Exposed bone in jaw (10071014)" as preferred terms, "antiresorptive drugs" as the target drugs, and primary suspect drug as the drug role code in the dataset. We evaluated the association between drugs and adverse events by using reporting odds ratio (ROR) based on disproportionality analysis. We took the High-Level Terms (HLT) of MedDRA® as the classification level of indications to calculate ROR to compare the signal difference of ONJ in different indications. In addition, patients with antiresorptive-induced osteonecrosis of the jaw and the time of onset of the condition following different antiresorptive medications were collected for the study. Results: The FAERS contained 18,421 reports relating to jaw osteonecrosis from January 2004 to September 2021. A total of eight antiresorptive agents were included in the analysis. From high to low, the ROR of ONJ induced by antiresorptive agents (regardless of indication) is pamidronate (ROR = 494.8), zoledronic acid (ROR = 431.9), denosumab (ROR = 194.8), alendronate (ROR = 151.2), risedronate (ROR = 140.2), etidronic acid (ROR = 64.5), ibandronate (ROR = 40.8), and romosozumab (ROR = 6.4). HLT ROR values for "metabolic bone disorders" were the lowest for each drug, while HLT ROR values were high for "tumor-related indications," including breast and nipple neoplasms malignant, plasma cell myelomas, and prostatic neoplasms malignant. The onset time for osteonecrosis of the jaw as median (Q1, Q3), osteoporosis-related indications, and the onset time for ONJ were 730 (368, 1268), 489.5 (236.3, 909.8), 722.5 (314, 1055), 761 (368, 1720), and 153 (50, 346) for zoledronic acid, denosumab, ibandronate, risedronate, and romosozumab, respectively. Cancer-related indications: the onset time for ONJ were 680.5 (255.3, 1283), 488 (245, 851), and 696.5 (347, 1087) for zoledronic acid, denosumab, and pamidronate, respectively. Conclusion: When antiresorptive drugs are used for metastasis, they have the largest risk signal, followed by malignancy, and the smallest is osteoporosis. The onset time of ONJ may not be related to the indications. The onset time of ONJ for BPs was about 2 years, denosumab about 1.3 years, and romosozumab less than 1 year, which may be related to sequential treatment. When used according to the instructions, the risk of ONJ caused by denosumab was higher than that of zoledronic acid, regardless of the indication. Based on these findings, researchers will continue to monitor and identify risk factors.

Risk factors associated with onset of medication-related osteonecrosis of the jaw in patients treated with denosumab

Objectives

While risk factors of bisphosphonate (BP) associated osteonecrosis of the jaw have been properly analyzed, studies focusing on risk factors associated with denosumab (DNO) are sparse. The purpose of this study was to identify risk factors influencing the onset of medication-related osteonecrosis of the jaw (MRONJ) in patients receiving antiresorptive treatment (ART) with DNO by comparing patients suffering from MRONJ and patients without MRONJ. Multiple variables were evaluated including the impact of a previous BP intake.

Materials and methods

A retrospective single-center cohort study with patients receiving DNO was conducted. One-hundred twenty-eight patients were included and divided into three groups: I (control, n = 40) receiving DNO with absence of MRONJ; group II (Test 1, n = 46), receiving DNO with presence of MRONJ; and group III (Test 2, n = 42) sequentially receiving BP and DNO with presence of MRONJ. Patients’ medical history, focusing on the identification of MRONJ risk factors, was collected and evaluated. Parameters were sex, age, smoking habit, alcohol consumption, underlying disease (cancer type, osteoporosis), internal diseases, additional chemo/hormonal therapy, oral inflammation, and trauma.

Results

The following risk factors were identified to increase MRONJ onset significantly in patients treated with DNO: chemo/hormonal therapy (p = 0.02), DNO dosage (p < 0.01), breast cancer (p = 0.03), intake of corticosteroids (p = 0.04), hypertension (p = 0.02), diabetes mellitus (p = 0.04), periodontal disease (p = 0.03), apical ostitis (p = 0.02), and denture use (p = 0.02). A medication switch did not affect MRONJ development (p = 0.86).

Conclusions

Malignant diseases, additional chemotherapy, DNO dosage, and oral inflammations as well as diabetes mellitus and hypertension influence MRONJ onset in patients treated with DNO significantly.

Clinical relevance

Patients receiving ART with DNO featuring aforementioned risk factors have a higher risk of MRONJ onset. These patients need a sound and regular prophylaxis in order to prevent the onset of MRONJ under DNO treatment.

New Generation of Meso and Antiprogestins (SPRMs) into the Osteoporosis Approach

Receptor activator of nuclear factor κB (RANK) and its ligand (RANKL) play key roles in bone metabolism and the immune system. The RANK/RANKL complex has also been shown to be critical in the formation of mammary epithelia cells. The female hormones estradiol and progesterone closely control the action of RANKL with RANK. Blood concentration of these sex hormones in the postmenopausal period leads to an increase in RANK/RANKL signaling and are a major cause of women's osteoporosis, characterized by altered bone mineralization. Knowledge of the biochemical relationships between hormones and RANK/RANKL signaling provides the opportunity to design novel therapeutic agents to inhibit bone loss, based on the anti-RANKL treatment and inhibition of its interaction with the RANK receptor. The new generation of both anti- and mesoprogestins that inhibit the NF-κB-cyclin D1 axis and blocks the binding of RANKL to RANK can be considered as a potential source of new RANK receptor ligands with anti-RANKL function, which may provide a new perspective into osteoporosis treatment itself as well as limit the osteoporosis rise during breast cancer metastasis to the bone.

Necrotising periodontal diseases and alcohol misuse - a cause of osteonecrosis?

'Necrotising periodontal diseases' is an umbrella term for necrotising gingivitis, necrotising periodontitis, necrotising stomatitis and noma. These rapidly destructive conditions are characterised by pain, interdental ulceration and gingival necrosis which, if left untreated, can result in osteonecrosis. Research indicates that patients with a history of alcohol misuse are at an increased risk of malnutrition, which negatively affects the immune response and predisposition to necrotising periodontal diseases. This article will discuss that osteonecrosis of the alveolar bone does not exclusively occur in association with antiresorptive medications, but can occur as a severe form of necrotising gingivitis. In this article, we will describe two cases to highlight the occurrence, presentation and management of necrotising periodontal diseases secondary to alcohol misuse.

Raises clinician awareness on the topic of necrotising periodontal diseases and describes diagnosis and treatment modalities.

Explores and explains the link between alcohol misuse, malnutrition and necrotising periodontal diseases.

Encourages dentists to liaise with healthcare professionals in the management of patients suffering from underlying comorbidities, highlighting the importance of holistic patient care.

Medication-related osteonecrosis of the jaw (MRONJ) and eNOS Polymorphisms in multiple myeloma patients: a single center experience

Background

Multiple myeloma (MM) constitutes approximately 10% of hematological malignancies. Bisphosphonates have established themselves in solid organ metastasis and multiple myeloma lytic bone lesions by inhibiting osteoclast activation. Medication-related osteonecrosis of the jaw (MRONJ) emerges as an important complication. Investigating host-based factors, and developing personal risk factors gain importance in the development mechanism of MRONJ. We aimed to reveal the different genotype polymorphisms, and clinical effects of eNOS in patients with a diagnosis of MRONJ in MM patients.

Methods

Medical records and blood samples were collected from 60 MRONJ patients with MM and 60 healthy controls. Inclusion criteria was having an exposed maxillofacial bone for more than eight weeks, a history of bisphosphonates, and no history of radiation therapy for the jaws. eNOS G894T and intron 4 VNTR were calculated by polymerase chain reaction and/or restriction fragment length polymorphism.

Results

eNOS G894T and VNTR genotypes and alleles were compared statistically with the healthy control group. There was no significant difference between the two groups. In comparison between G894T and clinical parameters, aphthous stomatitis was more common in TT genotype, while DMFT > 3 was more common in TG-GG genotype (p = 0.035, 0.023).

Conclusions

eNOS induces osteogenesis in bone metabolism, with its regulatory effects on bone remodeling and also NO induced angiogenesis takes place indirectly with its protective effect on endothelial functions. We see that these polymorphisms affecting the entire process of bone remodeling and angiogenesis, especially mucosal damage, which is the triggering factor of MRONJ pathology, have been revealed in the MM patient group. Considering the MRONJ initiating factors, it is necessary to emphasize the importance of our study results. It should be seen as an important step for new studies towards MRONJ and its treatment.

Osteonecrosis of the jaw secondary to haematopoietic stem cell transplantation

Osteonecrosis of the jaw (ONJ) is necrosis of mandibular or maxillary bone, which sometimes leads to bone exposure and sequestration. There is evidence that the microenvironment of the marrow stromal system is severely and irreversibly damaged after haematopoietic stem cell transplantation (HSCT) leading to a deficit in the quantity and quality of osteoblastic progenitors, compromising the ability to regenerate a normal osteogenic cell population and abnormality in bone remodelling/turnover. While osteonecrosis of the appendicular skeleton is a common complication after HSCT, there have been no reports of an association with ONJ. This is a report of the first case of ONJ secondary to HSCT in a 69-year-old woman who developed a unique pattern of osteonecrosis involving all four quadrants of the jaw 2 months after allogeneic stem cell transplantation.

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.

Smoking and alcohol consumption as risk factors in 112 oncology patients diagnosed with bisphosphonate-associated osteonecrosis of the jaw

Background: Bisphosphonate-associated osteonecrosis of the jaws (BAONJ) is a complication of great medical importance. Some of the most discussed and controversial aspects are the risk factors, some of which are related to patients' smoking and alcohol consumption. The Aim: To study cancer patients with BAONJ and determine their participation in the mentioned above risky health-related habits. Material and methods: A prospective epidemiological study of 112 patients diagnosed with bisphosphonate-associated osteonecrosis of the jaw in 2016 and 2017 was conducted at the Clinic of Maxillofacial surgery of University hospital "St. George", Plovdiv, Bulgaria, based on anamnesis, clinical examination, and hospital documentation. SPSS Statistics v.24 was used for statistical analysis, at a significance level p<0.05. Results: Over 2/3 of the patients were smokers (40.18%) or ex-smokers (25.00%), which linked them with the risk factor of smoking. At the time of the study, patients smoking between 1 and 9 and between 10 and 19 cigarettes a day had equal relative shares of 44.22%. More than half of the patients smoked from the age of 20-39, which we explain by the high average age. The majority of patients studied consumed alcohol, most often once a week or on weekends (28.57%) or only on occasions (26.79%), followed by 24.11% who used alcohol several times per week. Nearly 2/3 drink drinks with both low and high alcohol content. Conclusion: The highest proportion of patients are smokers / ex-smokers and consume alcoholic beverages occasionally, which links them to these risk potential factors.

Evaluation of periodontal health in breast cancer patients undergoing tamoxifen or aromatase inhibitors drugs therapy: A cross-sectional study

AIM

To study the dental and periodontal status of women with breast cancer (BCa) having tamoxifen or aromatase inhibitors (AIs) treatment in comparison with control healthy women.

METHODS

Fifty-one women on tamoxifen therapy, 52 women on AIs therapy and 52 systemically healthy controls were included in the study. The total number of teeth, the number of teeth indicated for extraction, the number of decayed teeth, and the duration of medication were recorded. Periodontal status was evaluated with gingival index (GI); plaque index (PI); bleeding on probing (BOP); probing depth (PD) and clinical attachment loss (CAL).

RESULTS

The lowest number of teeth and decayed teeth was found in AIs users (P < .001 and P = .003 respectively). The highest CAL value was seen in AIs users (P = .042) whereas no significant difference was found between the groups in terms of PI, GI, and PD (P = .102, P = .233, and P = .306, respectively). Lower PI was observed in patients using AIs for less than 2 years (P = .048).

CONCLUSIONS

While tamoxifen did not affect the dental and periodontal condition, AIs medication adversely affected the dental and periodontal condition by more tooth loss and higher CAL.

Spontaneous oral ulceration with bone sequestration: its relevance in current clinical practice

Oral ulceration associated with bony exposure and sequestration is uncommon and often related to well-recognised conditions. In a small group of patients no obvious aetiological factors can be elucidated, and various terminologies have been utilised to describe these lesions. We report six cases of spontaneous oral ulceration with bone sequestration as a specific entity and review the pertinent literature. We retrospectively reviewed patients presenting in the period 2013-2018. Data collected included demographic details, relevant medical, drug, and radiotherapy history; presentation, investigations, management, and outcome. Six patients with an age range of 49-65 years were identified with spontaneous oral ulceration with bone sequestration in the study period. All were males, and none had any relevant history. Five lesions occurred over the mylohyoid ridge and one was related to a lingual mandibular torus. The most common presentation was a painful ulcer with exposed bone, which had been present for 6 - 12 weeks. Occlusal radiographs demonstrated focal rarefaction in two patients. All were managed conservatively and by removal of the loose sequestrum. Healing occurred successfully in all cases, and this was earlier when the loose sequestrum was removed. Spontaneous oral ulceration with bone sequestration is a distinct lesion that most often presents over the prominence of the mylohyoid ridge. It is currently an uncommon entity (0.02%), but this could well be due to a lack of recognition and under-reporting. It should be considered as a diagnosis only when other causes have been excluded. Lesions heal successfully with conservative management and surgical intervention, and this occurs earlier following removal of the loose sequestrum.

Jaw Osteonecrosis Preceded by Dengue Fever - Possible Pathogenetic Mechanism

Introduction:

Osteonecrosis of jaw (ONJ) is a debilitating condition which can lead to compromised dentition. Various causes for ONJ are suggested in the literature such as drugs, trauma, radiation, chemicals, bacterial, and fungal infections. Knowing etiology for particular case of ONJ is important to prevent further progression of this debilitating condition. It is the first case of ONJ reported with dengue virus as a possible etiology.

Case Report:

This article presents a case of 46-year-old male patient with extensive osteonecrosis of maxilla preceded by dengue fever. In the present case, all known causes for osteonecrosis were ruled out. The present article discusses dengue infection as a possible etiologic agent for ONJ.

Conclusion:

In the present case, probable cause for ONJ can be established as a dengue virus necessitating the need for proper preventive methods to avoid further complication of osteonecrosis.

Zoledronate treatment duration is linked to bisphosphonate-related osteonecrosis of the jaw prevalence in rice rats with generalized periodontitis

OBJECTIVES

To determine the extent that zoledronate (ZOL) dose and duration is associated with bisphosphonate-related osteonecrosis of the jaw (BRONJ) prevalence in rice rats with generalized periodontitis (PD), characterize structural and tissue-level features of BRONJ-like lesions in this model, and examine the specific anti-resorptive role of ZOL in BRONJ.

MATERIALS AND METHODS

Rice rats (n = 228) consumed high sucrose-casein diet to enhance generalized PD. Groups of rats received 0, 8, 20, 50 or 125 µg/kg IV ZOL/4 weeks encompassing osteoporosis and oncology ZOL doses. Rats from each dose group (n = 9-16) were necropsied after 12, 18, 24 and 30 weeks of treatment. BRONJ-like lesion prevalence and tissue-level features were assessed grossly, histopathologically and by MicroCT. ZOL bone turnover effects were assessed by femoral peripheral quantitative computed tomography, serum bone turnover marker ELISAs and osteoclast immunolabelling.

RESULTS

Prevalence of BRONJ-like lesions was significantly associated with (a) ZOL treatment duration, but plateaued at the lowest oncologic dose, and (b) there was a similar dose-related plateau in the systemic anti-resorptive effect of ZOL. ZOL and BRONJ-like lesions also altered the structural and tissue-level features of the jaw.

CONCLUSION

The relationship between BRONJ-like lesion prevalence and ZOL dose and duration varies depending on the co- or pre-existing oral risk factor. At clinically relevant doses of ZOL, BRONJ-like lesions are associated with anti-resorptive activity.

Sialadenitis May Be Associated With an Increased Risk for Osteoradionecrosis: A Nationwide Population-Based Cohort Study

PURPOSE

The impact of sialadenitis on osteoradionecrosis (ORN) is controversial. The aim of this study was to determine the association between sialadenitis and ORN.

MATERIALS AND METHODS

Participants were derived from the Taiwanese Longitudinal Health Insurance Database. From January 1, 2000 to December 31, 2008, cases of sialadenitis (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] codes 527.2, 527.3, 527.5 to 527.7, 527.9, and 710.2) and ORN (ICD-9-CM codes 526.89, 526.5, 730.0, and 730.1) were identified. Different treatment modalities, including surgery versus medicine, were used to distinguish the severity of sialadenitis. The primary predictor variable was sialadenitis. The secondary predictor variable was severity of sialadenitis. The primary outcome variable was time to developing ORN. Other study variables were grouped for age, gender, risk factor, and medical treatment. Cox proportional hazard regression was used to investigate the associations between sialadenitis and ORN after adjusting for statistical confounders.

RESULTS

The sample was composed of 47,385 patients with a mean age of 46.6 years (standard deviation, 19.9 yr) and 37.2% were men. Twenty percent had a diagnosis of sialadenitis and 1.13% had a diagnosis of ORN. Sialadenitis was associated with an increased risk of ORN (hazard ratio [HR] = 1.93; 95% confidence interval [CI], 1.61-2.31; P < .0001). After adjustment for confounders, sialadenitis was associated with ORN (multivariable HR = 1.83; 95% CI, 1.52-2.19; P < .0001). Severity of sialadenitis was associated with an increased risk of ORN; risks for ORN were 1.79 (95% CI, 1.49-2.16; P < .0001) and 3.52 (95% CI, 1.67-7.44; P < .001) in patients with mild and serious sialadenitis, respectively, compared with the no-sialadenitis cohort. For the joint effect of ORN between sialadenitis and malignancy type, patients with sialadenitis had 11.6-fold risk for ORN (95% CI, 5.58-23.9) compared with patients without malignancy.

CONCLUSIONS

Sialadenitis markedly increased the risk to develop ORN. The severity of sialadenitis was positively correlated with the incidence of ORN.

Current Understanding of the Pathophysiology of Osteonecrosis of the Jaw

PURPOSE OF REVIEW

Osteonecrosis of the jaw (ONJ) is a rare and severe necrotic bone disease reflecting a compromise in the body's osseous healing mechanisms and unique to the craniofacial region. Antiresorptive and antiangiogenic medications have been suggested to be associated with the occurrence of ONJ; yet, the pathophysiology of this disease has not been fully elucidated. This article raises the current theories underlying the pathophysiology of ONJ.

RECENT FINDINGS

The proposed mechanisms highlight the unique localization of ONJ. The evidence-based mechanisms of ONJ pathogenesis include disturbed bone remodeling, inflammation or infection, altered immunity, soft tissue toxicity, and angiogenesis inhibition. The role of dental infections and the oral microbiome is central to ONJ, and systemic conditions such as rheumatoid arthritis and diabetes mellitus contribute through their impact on immune resiliency. Current experimental studies on mechanisms of ONJ are summarized. The definitive pathophysiology is as yet unclear. Recent studies are beginning to clarify the relative importance of the proposed mechanisms. A better understanding of osteoimmunology and the relationship of angiogenesis to the development of ONJ is needed along with detailed studies of the impact of drug holidays on the clinical condition of ONJ.

Medication-related osteonecrosis of the jaw: Prevention, diagnosis and management in patients with cancer and bone metastases

Medication-related osteonecrosis of the jaw (MRONJ) is primarily an adverse side effect of denosumab or bisphosphonates (particularly when used at high doses to prevent skeletal-related events [SREs] in patients with cancer and bone metastases) or possibly anti-angiogenic cancer treatment. While the implementation of preventive measures over recent years has reduced the risk of MRONJ in patients with bone metastases due to cancer, it is imperative to balance the risk of MRONJ against the beneficial effects of treatment with denosumab or bisphosphonates on the skeletal health of patients. Despite growing awareness of MRONJ within the medical community, there is a lack of large-scale, prospective clinical studies in this rapidly evolving field. Discussing preventive measures with patients and implementing them, both before and during treatment with bisphosphonates or denosumab, is the best option to reduce the risk of MRONJ. In particular, avoiding bone trauma and preventing and treating dental infections before and during denosumab or bisphosphonate therapy is crucial to minimize the risk of MRONJ. If MRONJ develops, conservative (non-surgical) treatment can provide symptom relief, but achieving mucosal closure remains challenging. When management of symptoms and mucosal healing are the ultimate goals of therapy, or after failure of conservative treatment, a surgical approach may be beneficial. This critical review, based on a best-evidence review of currently available literature, provides clear practical guidelines to help to prevent, manage and treat MRONJ. Overall, a multidisciplinary, pragmatic approach to MRONJ should be adopted, prioritizing patient's quality of life and management of their skeletal malignant disease.

A multicenter case registry study on medication-related osteonecrosis of the jaw in patients with advanced cancer

Purpose

This observational case registry study was designed to describe the natural history of cancer patients with medication-related osteonecrosis of the jaw (ONJ) and evaluate the ONJ resolution rate.

Methods

Adults with a diagnosis of cancer and with a new diagnosis of ONJ were enrolled and evaluated by a dental specialist at baseline and every 3 months for 2 years and then every 6 months for 3 years until death, consent withdrawal, or loss to follow-up. The primary endpoint was the rate and time course of ONJ resolution. Secondary endpoints included frequency of incident ONJ risk factors, ONJ treatment patterns, and treatment patterns of antiresorptive agents for subsequent ONJ.

Results

Overall, 327 patients were enrolled; 207 (63%) were continuing on study at data cutoff. Up to 69% of evaluable patients with ONJ had resolution or improvement during the study. ONJ resolution (AAOMS ONJ staging criteria) was observed in 114 patients (35%); median (interquartile range) time from ONJ onset to resolution was 7.3 (4.5–11.4) months. Most patients (97%) had received antiresorptive medication before ONJ development, 9 patients (3%) had not; 68% had received zoledronic acid, 38% had received denosumab, and 10% had received pamidronate (56% had received bisphosphonates only, 18% had received denosumab only, and 21% had exposure to both).

Conclusions

These results are consistent with those observed in clinical trials evaluating skeletal-related events in patients with advanced malignancy involving bone. Longer follow-up will provide further information on ONJ recurrence and resolution rates between medically and surgically managed patients.

Osteoradionecrosis of the jaws: definition, epidemiology, staging and clinical and radiological findings. A concise review

Osteoradionecrosis (ORN) of the jaws is a pernicious complication of radiation therapy for head and neck tumours. This article aims to provide an update on data related to the definition, epidemiology, staging, and clinical and radiological findings of ORN of the jaws. Using certain keywords, an electronic search was conducted spanning the period from January 1922 to April 2014 to identify the available related investigations. Pooled data were then analysed. ORN is described as exposed irradiated bone that fails to heal over a period of 3 months without evidence of persisting or recurrent tumour. The prevalence of ORN varies in the literature. Several staging or scoring systems of ORN have been proposed. Clinical findings include ulceration or necrosis of the mucosa with exposure of necrotic bone. Radiological findings are not evident in the early stages of ORN. Furthermore ORN may not be apparent in imaging even when the disease is advanced. Taking into account the severity of ORN and the difficulties in diagnosing it early and accurately, the clinician should be aware of this complex entity in order to prevent its appearance or the development of more severe complications.

Design of polyaspartic acid peptide-poly (ethylene glycol)-poly (ε-caprolactone) nanoparticles as a carrier of hydrophobic drugs targeting cancer metastasized to bone

Treatment of cancer metastasized to bone is still a challenge due to hydrophobicity, instability, and lack of target specificity of anticancer drugs. Poly (ethylene glycol)-poly (ε-caprolactone) polymer (PEG-PCL) is an effective, biodegradable, and biocompatible hydrophobic drug carrier, but lacks bone specificity. Polyaspartic acid with eight peptide sequences, that is, (Asp)₈, has a strong affinity to bone surface. The aim of this study was to synthesize (Asp)₈-PEG-PCL nanoparticles as a bone-specific carrier of hydrophobic drugs to treat cancer metastasized to bone. ¹H nuclear magnetic resonance, Fourier transform infrared spectroscopy, and transmission electron microscopy data showed that (Asp)₈-PEG-PCL nanoparticles (size 100 nm) were synthesized successfully. (Asp)₈-PEG-PCL nanoparticles did not promote erythrocyte aggregation. Fluorescence microscopy showed clear uptake of Nile red-loaded (Asp)₈-PEG-PCL nanoparticles by cancer cells. (Asp)₈-PEG-PCL nanoparticles did not show cytotoxic effect on MG63 and human umbilical vein endothelial cells at the concentration of 10-800 μg/mL. (Asp)₈-PEG-PCL nanoparticles bound with hydroxyapatite 2-fold more than PEG-PCL. Intravenously injected (Asp)₈-PEG-PCL nanoparticles accumulated 2.7-fold more on mice tibial bone, in comparison to PEG-PCL. Curcumin is a hydrophobic anticancer drug with bone anabolic properties. Curcumin was loaded in the (Asp)₈-PEG-PCL. (Asp)₈-PEG-PCL showed 11.07% loading capacity and 95.91% encapsulation efficiency of curcumin. The curcumin-loaded (Asp)₈-PEG-PCL nanoparticles gave sustained release of curcumin in high dose for >8 days. The curcumin-loaded (Asp)₈-PEG-PCL nanoparticles showed strong antitumorigenic effect on MG63, MCF7, and HeLa cancer cells. In conclusion, (Asp)₈-PEG-PCL nanoparticles were biocompatible, permeable in cells, a potent carrier, and an efficient releaser of hydrophobic anticancer drug and were bone specific. The curcumin-loaded (Asp)₈-PEG-PCL nanoparticles showed strong antitumorigenic ability in vitro. Therefore, (Asp)₈-PEG-PCL nanoparticles could be a potent carrier of hydrophobic anticancer drugs to treat the cancer metastasized to bone.

Elevation of pro-inflammatory cytokine levels following anti-resorptive drug treatment is required for osteonecrosis development in infectious osteomyelitis

Various conditions, including bacterial infection, can promote osteonecrosis. For example, following invasive dental therapy with anti-bone resorptive agents, some patients develop osteonecrosis in the jaw; however, pathological mechanisms underlying these outcomes remain unknown. Here, we show that administration of anti-resorptive agents such as the bisphosphonate alendronate accelerates osteonecrosis promoted by infectious osteomyelitis. Potent suppression of bone turnover by these types of agents is considered critical for osteonecrosis development; however, using mouse models we found that acceleration of bone turnover by teriparatide injection did not prevent osteonecrosis but rather converted osteoclast progenitors to macrophages expressing inflammatory cytokines, which were required for osteonecrosis development. In fact, we demonstrate that TNFα-, IL-1α/β- or IL-6-deficient mice as well as wild-type mice administered a TNFα-inhibitor were significantly resistant to development of osteonecrosis accompanying infectious myelitis, even under bisphosphonate treatment. Our data provide new insight into mechanisms underlying osteonecrosis and suggest new ways to prevent it.

Osteonecrosis of the jaw associated with ziv-aflibercept

Medication-related osteonecrosis of the jaw (MRONJ) has been associated with medications that include bisphosphonates (BPs), denosumab, bevacizumab and sunitinib. Ziv-aflibercept is a recombinant human vascular endothelial growth factor (VEGF) receptor which has been used to treat patients with various advanced solid tumors. We report three patients without a history of the use of medications known to cause MRONJ presenting with jaw osteonecrosis typical for MRONJ following therapy with ziv-aflibercept. All patients had metastatic gastrointestinal cancer treated with ziv-aflibercept and were evaluated for MRONJ because of exposed bone in the oral cavity. None of the patients had received antiresorptive therapies or any other medication known to cause MRONJ, and none had received radiation therapy to the jaws. Patients were aged 43, 51, 63 and all were males. Patients received 7, 16 and 23 cycles of ziv-aflibercept treatment and developed necrotic bone. All three patients presented with mandibular involvement, with two reporting pain. Patients were managed with anti-microbial mouth rinse, antibiotics and non-surgical sequestrectomy and followed up for 1.5, 2, and 2 months; two patients became asymptomatic while one patient continued to have pain. These three reported patients with a history of ziv-aflibercept therapy and no reported use of other medications known to cause MRONJ developed exposed necrotic bone of the jaw. We believe that ziv-aflibercept is another medication that can potentially cause MRONJ probably through its anti-VEGF activity, similar to bevacizumab and sunitinib.

Delayed wound healing after tooth extraction and self-reported kyphosis in Japanese men and women

It is unclear whether osteoporosis itself is a main risk factor for delayed wound healing after tooth extraction in humans. In this study, we evaluated the association between experience of delayed wound healing after last tooth extraction and self-reported kyphosis, with the possibility of having vertebral fractures, in Japanese patients. Among the 1,504 patients who responded to the structured questionnaire survey, 518 patients (134 men and 384 women) aged 55-97 years finally participated in this study. Patients who self-reported mild-moderate kyphosis were more likely to have problematic delayed wound healing after last tooth extraction than those who reported severe kyphosis (odds ratio [OR] 4.98; 95% confidence interval [CI], 1.86-13.38 and OR 2.30; 95% CI, 0.52-10.22, respectively) (p for trend = 0.005). Japanese patients with vertebral fractures may have a higher risk of having problematic delayed wound healing after tooth extraction.

Self-reported oral health and quality of life of postmenopausal breast cancer survivors on aromatase inhibitors and women without cancer diagnoses: a longitudinal analysis

INTRODUCTION

Aromatase inhibitors (AIs) are a well-established component of adjuvant therapy in postmenopausal women with hormone receptor (HR) + early stage breast cancer (BCa). We explored in an 18-month cohort study whether subjective oral health (OH), subjective periodontal health (PH), and oral health-related quality of life (OHRQoL) of postmenopausal BCa survivors on AIs differ from those of women without cancer diagnoses, and whether saliva flow, OH, PH, and OHRQoL are related.

METHODS

Data were collected from 29 postmenopausal BCa survivors on AIs and 29 postmenopausal women without cancer diagnoses. Socio-demographic information, OH, PH, and OHRQoL were collected at baseline and 6, 12, and 18 months later. Unstimulated whole saliva volume per 15 min was determined by drooling.

RESULTS

The two groups did not differ in background characteristics at baseline. Women on AIs had poorer OH (p = .043), PH (p = .04), and OHRQoL (p = .017), and lower saliva flow rate (p < .001) than control respondents. BCa survivors had the poorest PH at the 18-month visit. Xerostomia was correlated with OH at baseline and with OH and PH at 18 months. However, objective saliva flow rate was not correlated with OH or OHRQoL at this visit.

CONCLUSIONS

This study is the first to investigate the effects of AIs on patients' subjective OH, subjective PH, and OHRQoL. The data suggest that women treated with AIs have worse OH, PH, and OHRQoL than women without cancer diagnoses. Interprofessional care is recommended so that women on AIs receive optimal supportive oral care to assure long-term OH and positive OHRQoL.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01272570 https://clinicaltrials.gov/ct2/show/NCT01272570 .

Lack of cooperation between physicians and dentists during osteoporosis treatment may increase fractures and osteonecrosis of the jaw

OBJECTIVE

Our previous questionnaire-based survey suggested that discontinuation of antiresorptive agents before tooth extraction may increase adverse events and disturb osteoporosis treatment without completely preventing osteonecrosis of the jaw (O.N.J.). We also found little cooperation between physicians and dentists in Japan. However, limitations of our previous study included a survey of doctors belonging to small clinics and a small sample size. Our current study aimed to confirm the results of our previous survey in doctors mainly belonging to academia.

METHODS

A structured questionnaire including 14 key clinical queries was sent to 1812 physicians of the Japan Osteoporosis Society, and 629 responses were received.

RESULTS

Dentists requested discontinuation of many medications that were not associated with the incidence of O.N.J. A total of 523 respondents had received discontinuation requests from dentists. Of these, 97 respondents experienced 119 adverse events including 25 fractures and seven incidences of O.N.J. The ratios of valid responses for fractures were 3.6% and 5.3% in patients with a discontinuation of <3 and ≥3 months, respectively. Those for O.N.J. were 0.7% and 1.6%, respectively. Respondents who refused discontinuation requests reported no cases of O.N.J. Approximately 17% of respondents had patients who discontinued osteoporosis treatment following a requested drug discontinuation after tooth extraction. Approximately 62% of respondents did not request oral health care by a dentist before antiresorptive therapy, and 72% reported no cooperation between physicians and dentists in their region.

CONCLUSIONS

This study reconfirms the results of our previous survey. Discontinuation of antiresorptive treatment may increase both fractures and O.N.J. Immediate development of a strategy for sharing information about O.N.J. among physicians, dentists, and patients is required to reduce the incidence of both O.N.J. and skeletal events in osteoporosis treatment. Study limitations were selection bias due to low response rate and possible inaccurate responses to the questionnaire.

Systematic review of oral ulceration with bone sequestration

BACKGROUND

This article represents the first systematic review entirely dedicated toward a disease called oral ulceration with bone sequestration (OUBS). We performed this review in order to further define and outline this disease. A secondary interest was to recognize the prevalence and importance of OUBS in relation to other oral disorders accompanied by ulceration and bone exposure.

MATERIAL AND METHODS

The systematic review was registered with PROSPERO (registration number CRD42015024294) and performed in cooperation with Harvard's Countway Library. Searches were built using MeSH terms and proximity operators previously mentioned in OUBS descriptions. Database searches were performed through EMBASE, Medline, and PubMed, followed by a handsearch of bibliographies for relevant articles. Articles were assessed against eligibility and inclusion criteria centering on bone exposure without known etiologic cause. We sought to gather information on patient age, sex, anatomical location, clinical presentation, and comorbidities. PRISMA guidelines were followed.

RESULTS

The searches identified 766 records total. Despite considerable inspection, we found only 8 articles qualifying for our review. In the 8 articles, there were a total of 24 patients fulfilling the criteria of OUBS. Although some abstracts mentioned idiopathic nature, most authors presented clinical cases with probable causes to ulceration and sequestration. The mean age of these patients was 43.21 ± 11.94 years. The male to female ratio was 3:1. The predominant area of occurrence was the mandible (n = 23, 95.8%).

CONCLUSION

The representation of OUBS in the literature remains scarce. More data must be generated and gathered on the concept of OUBS so as to determine the true incidence and importance of this disease. Despite rare occurrences of conditions characterizing OUBS, the recent discussion of this topic in the scientific community calls for more knowledge to be brought forth, with great benefit to patients suffering from ulcerative diseases and osteonecrosis.

Impact of Osteonecrosis of the Jaw on Osteoporosis Treatment in Japan: Results of a Questionnaire-Based Survey by the Adequate Treatment of Osteoporosis (A-TOP) Research Group

Dentists request a discontinuation of antiresorptive agents, such as bisphosphonate, before and after tooth extractions to prevent osteonecrosis of the jaw (ONJ). However, little is known about how this affects ONJ and osteoporosis treatment and how medical professionals and dentists cooperate to treat ONJ in patients with osteoporosis. This study aimed to clarify the impact of ONJ on osteoporosis treatment in Japan. A structured questionnaire including 14 key clinical queries was sent to 488 medical professionals as part of the Japanese Osteoporosis Intervention Trial (JOINT)-04, and 206 responses were received. A total of 173 respondents had received discontinuation requests from dentists. Of these, 28 respondents experienced 30 adverse events including ten fractures and one incidence of ONJ. The respondents who refused discontinuation requests observed no cases of ONJ. Approximately 16 % of respondents had patients who discontinued osteoporosis treatment, following a requested drug discontinuation, after tooth extraction. Dentists requested discontinuations for many medications that were not associated with the incidence of ONJ. Approximately 76 % of respondents had never requested oral health care from dentists before osteoporosis treatment and 72 % reported no cooperation between dentists and medical professionals in their region. Our results suggest that drug discontinuation may increase adverse events and disturb osteoporosis treatment without completely preventing ONJ. Currently, both medical professionals and dentists in Japan still continue to recommend their own treatment position. A forum to share information about ONJ among medical professionals, dentists, and patients is required.

Tissue repair in osteoradionecrosis using pentoxifylline and tocopherol--report of three cases

PURPOSE

Osteoradionecrosis is a complication of head and neck radiotherapy, with a difficult resolution and no well-established treatment. The disease progression can cause important loss on patient's quality of life after cancer treatment. The options for treatment are limited and include clinical monitoring, prescription, or surgical procedures. As an alternative for bone necrosis treatment, a combination of drugs, pentoxifylline and tocopherol, can be used. Studies have shown that this combination significantly reduces chronic radiotherapy damage. The article reports successful treatment with this prescription protocol.

METHODS

We report three cases of patients referred to the Service of Oral and Maxillofacial Surgery at Erasto Gaertner Hospital, in Curitiba, Brazil. They were submitted to radiotherapy for the treatment of malignant head and neck tumors and later developed osteoradionecrosis. They were treated with the combination pentoxifylline and tocopherol.

RESULTS

All patients achieved complete remission in less than 1 year, with complete healing of bone exposure and without clinical symptoms.

CONCLUSIONS

This results show that this combination of drugs is beneficial in cases of bone necrosis induced by radiation, avoiding more aggressive treatments and reducing morbidity.

Non-Radiation-Related Osteonecrosis of the Jaws in Dogs: 14 Cases (1996-2014)

Osteonecrosis of the jaws (ONJ) is an entity of major clinical impact characterized by chronically exposed necrotic mandibular or maxillary bone. Its clinicopathological characteristics and possible inciting or risk factors are well described in humans but only anecdotally reported in dogs. Treatment modalities and outcome vary depending on the inciting factors involved and the extent and severity of the lesions. The objectives of this study were to retrospectively describe the clinicopathological features of non-radiation-related ONJ in a series of 14 dogs, identify possible inciting or risk factors, and report on the surgical treatment and outcome. For all patients, the medical records were used to collect information regarding signalment, clinical signs, characteristics of the oral, jaw and dental lesions, diagnostic imaging findings, histopathological and microbiological analysis, treatment performed, and outcome. The data collected showed that non-radiation-related ONJ appears to be an infrequent clinical entity but of significant impact in dogs; that a history of systemic antibiotics and dental disease is common among affected dogs; that previous dental extractions are commonly associated with ONJ sites; that using a systematic diagnostic approach is essential for diagnosis; and that thorough surgical debridement combined with a course of oral antibiotics was effective in the described dogs affected by advanced non-radiation-related ONJ.

Management of bisphosphonate-related osteonecrosis of the jaw: a literature review

Osteonecrosis of the jaw (ONJ) is a serious side effect of bisphosphonate use in patients with osteoporosis, Paget's disease, hypercalcemia of malignancy, metastatic bone disease and multiple myeloma, although recently this complication has also been reported in patients under non-bisphosphonate medication, such as denosumab and bevacizumab. The occurrence of ONJ is higher in oncology patients treated with high-dose iv bisphosphonates than in osteoporosis patients treated with oral bisphosphonates. Although multiple hypotheses have been proposed, the exact pathogenic mechanism of ONJ still remains unclear. As treatment protocols based on randomized controlled trials (RCTs) do not exist, we critically reviewed the existing data concerning the management of bisphosphonate-related osteonecrosis of the jaw, including the most recent data for the use of teriparatide and hyperbaric oxygen.

Infection and Medication-related Osteonecrosis of the Jaw

Medication-related osteonecrosis of the jaw (MRONJ), although initially believed to be exclusively associated with bisphosphonates, has been implicated in recent reports with additional drugs, especially the bone antiresorptive denosumab. The pathophysiology has not been fully elucidated, and no causal association between bone antiresorptive regimens and MRONJ has yet been established. However, reduced bone turnover and infection, an almost universal finding, are thought to be central to the pathogenesis of MRONJ. Both bisphosphonates and denosumab, through different pathways of action, significantly reduce the rate of bone turnover and potentially reduce the efficacy of the host defense against infection. Recent evidence questions the simplified etiology of low bone turnover causing MRONJ and offers evidence on the prominent role of infection instead. The management of MRONJ remains a significant clinical challenge, with little progress having been made on treatment. The aim of this article is to explore the current theories on the etiology of MRONJ and to emphasize the importance of infection in the development of this devastating pathology.

Bone Tissue Engineering Challenges in Oral & Maxillofacial Surgery

Over the past decades, there has been a substantial amount of innovation and research into tissue engineering and regenerative approaches for the craniofacial region. This highly complex area presents many unique challenges for tissue engineers. Recent research indicates that various forms of implantable biodegradable scaffolds may play a beneficial role in the clinical treatment of craniofacial pathological conditions. Additionally, the direct delivery of bioactive molecules may further increase de novo bone formation. While these strategies offer an exciting glimpse into potential future treatments, there are several challenges that still must be overcome. In this chapter, we will highlight both current surgical approaches for craniofacial reconstruction and recent advances within the field of bone tissue engineering. The clinical challenges and limitations of these strategies will help contextualize and inform future craniofacial tissue engineering strategies.

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.

Osteonecrosis of the maxilla related to long-standing methamphetamine abuse: a possible new aspect in the etiology of osteonecrosis of the jaw

BACKGROUND

Osteonecrosis of the jaw (ONJ) related to toxic effects of illicit drugs such as cocaine is not very common and might be overshadowed today by the incidence of bisphosphonate-related osteonecrosis of the jaw. However, we present a case which suggests a close relationship between abuse of the illicit drug methamphetamine (MA) and ONJ.

CASE REPORT

A 44-year-old male with extended osteonecrosis of the maxilla admitted chronic abuse and synthesis of MA for at least the previous two decades. Furthermore, he confessed self-extracting teeth since he became addicted to MA. However at presentation, he had been successfully cured of his addiction to MA. A step-by-step surgical treatment was planned using computer-aided design/computer-aided manufacturing techniques. After resection of necrotic bone, a vascularized osteomyocutaneous fibular flap was applied secondarily.

DISCUSSION

Two possible mechanisms, alone or in combination, could possibly lead to MA-related ONJ. Self-extraction of teeth as a psychopathologic behavior of self-destruction among MA abusers results in wounds that allow unhindered invasion of microorganisms causing osteomyelitis and ONJ, while on the other hand, the heating of white phosphor releases toxic phosphorous vapor, which could be inhaled and consequently cause ONJ of the maxilla. However, since the worldwide prevalence of MA abuse is remarkably high, a relationship between MA abuse and ONJ will offer a new aspect in the etiology of ONJ and might present a further therapeutic challenge.

A network modeling approach for the spatial distribution and structure of bone mineral content

This study aims to develop a spatial model of bone for quantitative assessments of bone mineral density and microarchitecture. A spatially structured network model for bone microarchitecture was systematically investigated. Bone mineral-forming foci were distributed radially according to the cumulative normal distribution, and Voronoi tessellation was used to obtain edges representing bone mineral lattice. Methods to simulate X-ray images were developed. The network model recapitulated key features of real bone and contained spongy interior regions resembling trabecular bone that transitioned seamlessly to densely mineralized, compact cortical bone-like microarchitecture. Model-simulated imaging profiles were similar to patients' X-ray images. The morphometric metrics were concordant with microcomputed tomography results for real bone. Simulations comparing normal and diseased bone of 20-30 to 70-80 year-olds demonstrated the method's effectiveness for modeling osteoporosis. The novel spatial model may be useful for pharmacodynamic simulations of bone drugs and for modeling imaging data in clinical trials.

Anti-resorptive osteonecrosis of the jaws: facts forgotten, questions answered, lessons learned

Osteonecrosis of the jaws associated with bisphosphonate and other anti-resorptive medications (ARONJ) has historically been a poorly understood disease process in terms of its pathophysiology, prevention and treatment since it was originally described in 2003. In association with its original discovery 11 years ago, non-evidence based speculation of these issues have been published in the international literature and are currently being challenged. A critical analysis of cancer patients with ARONJ, for example, reveals that their osteonecrosis is nearly identical to that of cancer patients who are naive to anti-resorptive medications. In addition, osteonecrosis of the jaws is not unique to patients exposed to anti-resorptive medications, but is also seen in patients with osteomyelitis and other pathologic processes of the jaws. This article represents a review of facts forgotten, questions answered, and lessons learned in general regarding osteonecrosis of the jaws.

Bisphosphonate related osteonecrosis of the jaw: a study of 18 cases associated with fungal infection

Osteonecrosis of the jaw (ONJ) is a serious complication associated with oral and intravenous bisphosphonate therapy. Its pathogenesis is not well understood and its management is difficult. Microbiological investigations have detected a variety of oral pathogens such as Actinomyces, Enterococcus, Candida albicans, Aspergillus, Haemophilus influenzae, alpha-hemolytic streptococci, Lactobacillus, Enterobacter, and Klebsiella pneumoniae. To better treat it, it is important to understand its causes and complications. Materials and Methods. Our present study addresses a microscopic observation of curetted jaw necrotic lesions related to bisphosphonates. Results. A mycotic infestation has been found in all of the 18 cases studied. Discussion. An identification of the fungal agent and its incrimination in the pathogenesis of bisphosphonates related osteonecrosis of the jaw could change radically the management of this condition.

Molecular alterations of bone quality in sequesters of bisphosphonates-related osteonecrosis of the jaws

Compared to healthy bone, the intrinsic bone materials properties in the pre-existing lamellar bone are altered in jaw bone sequesters of bisphosphonates (BP)-related osteonecrosis.

INTRODUCTION

The aim of this study was to evaluate the human jaw bone quality, especially intrinsic bone material properties among sequesters of osteonecrosis of the jaw (ONJ) induced by BP.

METHODS

Bone sequesters were obtained from 24 patients suffering from ONJ following a BP treatment. Within BP-exposed bone samples, benign-BP and malignant-BP groups were distinguished in relation to the underlying disease: osteoporosis and bone metastases or multiple myeloma, respectively. Healthy cadaveric cortical jaw bone samples were used as controls. The physicochemical parameters of bone samples - mineral/organic ratio, relative proteoglycan content, crystallinity, monohydrogen phosphate content, and type-B carbonate substitution - were evaluated by Raman microspectroscopy. Representative Raman spectral features of bones control and BP-exposed bone sequesters were identified with the Partial-Least-Square Discriminant Analysis (PLS-DA).

RESULTS

BP-exposed bone sequesters are characterized by a significant increase of mineral to organic ratio (+12 %) and a significant decrease of relative proteoglycan content (-35 %), thus regulating initial collagen matrix mineral deposition. Structural changes on mineral components are revealed by a significant decrease of both crystallinity (-2 %) and mineral maturation (-41 %) in the BP-exposed bone sequesters compared to healthy bones. These modifications were also observed distinctly in both benign-BP and malignant-BP groups. In addition, a shift of the phosphate ν1 band was highlighted by PLS-DA between bones control and BP-exposed bone sequesters, revealing a disruption of the apatitic phosphate environment in the jaw bone sequesters.

CONCLUSIONS

The present data show that jaw bone quality can be altered with an overmineralization and ultrastructural modifications of apatitic mineral in bone sequesters of BP-related ONJ.

Bisphosphonate-related osteonecrosis of the jaw mimicking bone metastasis

Osteonecrosis of the jaw is usually a potential complication of bisphosphonate therapy. In a cancer patient, this disease entity can be misdiagnosed as a metastatic lesion. Our aim is to make clinicians aware of bisphosphonate associated osteonecrosis of the jaw to prevent misdiagnosis and initiate proper treatment at the earliest. We present the case of a breast cancer patient with multiple bony metastases and a jaw lesion presumed to be metastases. After no response to palliative radiation, repeat radiological imaging studies revealed osteonecrosis of the jaw. Correlating a patient's clinical information with findings on diagnostic imaging studies, such as SPECT bone and CT scans, can help identify this potential complication of bisphosphonate treatment. Early diagnosis helps minimize unnecessary biopsies and allows for the proper treatment to be instituted.

Histological findings on jaw osteonecrosis associated with bisphosphonates (BONJ) or with radiotherapy (ORN) in humans

OBJECTIVE

To describe the histological features of bone tissue harvested from patients affected by jaw osteonecrosis associated with bisphoshponates (BONJ) or with radiotherapy (ORN), in undecalcified ground sections.

MATERIALS AND METHODS

Sixteen bone tissue samples from 14 patients with BONJ and two patients with ORN were processed in order to obtain both ground, undecalcified sections and decalcified sections. The sections underwent histometric and morphometric analysis.

RESULTS

Bone tissue samples obtained from patients with BONJ or ORN of the jaws shared some histological characteristics. Common histological features included the loss of bone architecture, the absence of a proper Haversian system and proper marrow spaces, the presence of necrotic spots of non-mineralized tissue, areas of empty osteocytic lacunae next to areas of hypercellularity, the presence of resorption pits with rare osteoclast-like cells and the presence of bacteria and of an inflammatory infiltrate. A violet rib of tissue characterized by large resorption pits facing was frequently observed between the mineralized bone and the inflammatory infiltrate.

CONCLUSIONS

The histological features of BONJ and ORN are similar and resemble those of osteomyelitis. Even though it is not clear whether infection is the cause or consequence of bone exposure, inflammatory cells, bacteria or their products may have a massive, direct lytic effect on bone tissue challenged by bisphosphonates.

Long-term treatment with intravenous bisphosphonates in metastatic breast cancer: a retrospective study

Bisphosphonates are important therapies used to reduce the risk of skeletal-related events in patients with bone metastases from breast cancer (BC). This retrospective cohort study evaluated the incidence of osteonecrosis of the jaw (ONJ) and renal impairment in women (n = 221) with bone metastases from BC treated with intravenous bisphosphonates from January 1999 to June 2008. In the long-term cohort, 159 patients received pamidronate (n = 9), zoledronic acid (n = 110), or both (n = 40) for ≥24 months. The comparator group consisted of patients treated with intravenous bisphosphonates for 12-23 months (n = 62). After 39 months' median follow-up, six of 159 patients developed ONJ (3.8%; median 38.5 treatment cycles and 44 months' exposure) in the long-term cohort. Of patients who developed ONJ, 50% resumed intravenous bisphosphonates after a 12-month treatment holiday. Renal impairment developed in 19 patients in the long-term cohort (11.9%; median 26 treatment cycles and 26 months' exposure). Of these 19 patients, 11 (57.9%) recovered baseline renal function and seven (36.7%) showed partial recovery. After modification of the intravenous bisphosphonate regimen, 17 of 19 patients (89.4%) resumed therapy. Of the 62 patients in the comparator cohort, one patient developed ONJ (1.6%) and six developed renal impairment (9.7%). Similar incidence rates of ONJ and renal impairment were observed for the long-term and comparator cohorts. Times to ONJ or renal impairment also were similar across intravenous bisphosphonate type. Long-term (≥24 months) intravenous bisphosphonate use in metastatic BC is well tolerated, with low incidences of ONJ and renal impairment.