Updates on bisphosphonates and potential pathobiology of bisphosphonate-induced jaw osteonecrosis

Novel Histopathological Findings of Micro Bone Fragments and Epithelial Response in the Oral Mucosa in Bisphosphonate-Related Osteonecrosis of the Jaw

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) occurs in the jawbone and interfacing oral mucosa of patients treated with bisphosphonates. Herein, we report novel histopathological findings in the oral mucosa of a surgical specimen obtained from a 61-year-old man with BRONJ. The resected jawbone and adjacent oral mucosa were separated for histological examination. The mucosal tissue was examined using Von Kossa staining and immunohistochemical (CK5/6, p63) staining of non-decalcified paraffin sections. Pseudoepitheliomatous hyperplasia (PEH), a microscopic feature of the mucosal epithelium in BRONJ, was observed in soft tissue specimens, concomitant with inflammatory cell infiltration. Von Kossa staining revealed small fragments of necrotic bone, tens to hundreds of micrometers in size, scattered within the connective tissues; the PEH forefront contacted some of the bone fragments. Immunohistochemical staining demonstrated that occasionally, the PEH not only contacted but also encompassed the bone fragments. To our knowledge, this is the first report of presence of micro bone fragments and their association with PEH in the oral mucosa in BRONJ.

Application of Panoramic Radiography in the Detection of Osteopenia and Osteoporosis-Current State of the Art

PURPOSE OF REVIEW

Osteoporosis ranks high among morbidities in the elderly as it is a natural process to lose bone, making them susceptible to fractures from minor falls. The cost of managing these patients is staggering. The fractures can be prevented with better care of the elderly, and by treating the major predisposing factor, osteoporosis. Clinicians and scientists, in general, constantly look for early diagnostic and prognostic indicators for osteopenia and osteoporosis to proactively prevent fractures. Dental panoramic radiography (DPR) is a rotational pantomography used for identifying dental pathology in patients. Early signs of osteopenia and osteoporosis can be identified in DPR. The usefulness of notable jaw changes in DPR to predict osteopenia and osteoporosis is still evolving as more studies continue to delve into this concept. The purpose of this review is to present advances made in the practical application of DPR for predicting early onset of osteopenia and osteoporosis.

RECENT FINDINGS

Dental panoramic radiography, a form of tomography commonly used by dental practitioners, has been the standard of care for decades for detecting dento-alveolar pathology. Several technological advancements have taken place with respect to the use of DPR. These include conversion from plain film to digital radiography, advancements in the manufacture of flat panel detectors, and accurate imaging of the layers of mandible and maxilla that has become possible with appropriate patient positioning within the focal trough of the machine. Improvements in the software infrastructure make it easier to view, enhance, and save the radiographic images. The radiographic appearance of the trabecular bone within the mandible and indices measured from the dental panoramic radiographs focusing on the inferior cortex of the mandible are considered useful tools for identifying asymptomatic individuals with osteoporosis or at risk for developing osteoporosis. These indices apparently correlate with risks of fragility fractures of osteoporosis in other parts of the body. Dental panoramic radiography (DPR) is a commonly used radiographic procedure in dentistry for evaluation of teeth and associated maxillofacial structures. The evaluation of the inferior border of the mandible for reduction or loss of cortical thickness and evaluation of the trabecular bone within the mandible are helpful markers for early signs of osteopenia to identify patients at risk for osteoporosis. This review focused on research advancements on practical application of DPR in early identification of osteopenia and osteoporosis.

Zoledronic acid affects the process of Porphyromonas gingivalis infecting oral mucosal epithelial barrier: An in-vivo and in-vitro study

Zoledronic acid (ZA), one of the commonly used bisphosphonates, is mainly used for bone-metabolic diseases. Studies proved that ZA has adverse effects on oral soft tissues. As the first line of innate immunity, the gingival epithelium could be infected by periodontal pathogens, which is a key process of the initiation of periodontal diseases. Yet, how ZA affects the periodontal pathogens infecting the epithelial barrier remains unclear. This study aimed to investigate the influences of ZA on the process of Porphyromonas gingivalis (P. gingivalis) infecting the gingival epithelial barrier via in-vitro and in-vivo experiments. In the in-vitro experiments, under the condition of different concentrations of ZA (0, 1, 10, and 100 μM), P. gingivalis was used to infect human gingival epithelial cells (HGECs). The infections were detected by transmission electron microscope and confocal laser scanning microscope. Besides, the internalization assay was applied to quantify the P. gingivalis, which infected the HGECs, in the different groups. To evaluate the expression levels of pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, and IL-8, by infected HGECs, real-time quantitative reverse transcription-polymerase chain reactions were applied. In the in-vivo experiments, rats were given ZA solution (ZA group) or saline (control group) by tail intravenous injection for 8 weeks. Subsequently, we put ligatures around the maxillary second molars of all the rats and inoculated P. gingivalis to the gingiva every other day from day 1 to day 13. The rats were sacrificed on days 3, 7, and 14 for micro-CT and histological analyses. The in-vitro results manifested that the quantity of P. gingivalis that had infected HGECs increased with the ZA concentrations. Pro-inflammatory cytokines expression by HGECs were significantly increased by 100 μM ZA. In the in-vivo study, compared to the control group, more P. gingivalis was detected in the superficial layer of gingival epithelium in the ZA group. Besides, ZA significantly increased the expression level of IL-1β on day 14 and IL-6 on days 7 and 14 in gingival tissues. These findings suggest that the oral epithelial tissues of patients who receive high-dose ZA treatment may be more susceptible to periodontal infections, resulting in severe inflammatory conditions.

Bisphosphonates: From Pharmacology to Treatment

Bisphosphonates are among the most widely used drugs in the world for their many clinical indications. Their mechanism of action is based on the increase in the level of bone mineralization through the inhibition of osteoclastic activity and the induction of osteoblastic activity. Recent studies also attribute to bisphosphonates an antineoplastic activity, due to the ability of these drugs to inhibit neo angiogenesis, inhibiting the proliferation of endothelial cells. Bisphosphonates have several common properties, including poorly absorbed orally, high affinity for bone mineral, inhibitory effects on osteoclastic bone resorption, prolonged bone retention, and elimination in the urine. Bisphosphonates are generally well tolerated but their use can be, however, burdened by serious side effects such as hypocalcaemia, renal impairment, and aseptic osteonecrosis of the jaw.

Therapeutic effect of alendronate in an experimental temporomandibular joint osteoarthritis

BACKGROUND

Temporomandibular joint osteoarthritis is a common degenerative joint disease. This disease negatively affects the daily life, speech and chewing functions of patients.

OBJECTIVE

This study aimed to evaluate the effects of intra-articular injection of alendronate to osteoarthritis, which has a protective effect on bone and cartilage tissue and helps reduce inflammation in temporomandibular joint osteoarthritis.

METHODS

A total of 24 Wistar albino rats were used in the study. Rats were divided into four groups: study, saline, control and sham. In both saline and control groups, monosodium iodoacetate was injected intra-articularly to induce osteoarthritis. Alendronate was administered intra-articularly to the study group weekly for 4 weeks. In the saline group, saline was administered by intra-articular injection. At the end of the 12th week, all groups were sacrificed. Mandibular condyle tissues were examined histopathologically.

RESULTS

According to the results, osteoarthritic changes in the control group were higher than those in the study group (p < .05). No significant reduction in osteoarthritic changes was observed in the saline group (p > .05). Significant osteoarthritis findings were observed in all groups compared with the sham group (p < .05).

CONCLUSION

Intra-articular injection of alendronate was found to have positive results on TMJ osteoarthritis. In addition, it was seen that alendronate has effects on reducing cartilage tissue degeneration and loss of matrix proteins.

Impacts of bisphosphonates on the bone and its surrounding tissues: mechanistic insights into medication-related osteonecrosis of the jaw

Bisphosphonates are widely used as anti-resorptive agents for the treatment of various bone and joint diseases, including advanced osteoporosis, multiple myeloma, bone metastatic cancers, Paget's disease of bone, and rheumatoid arthritis. Bisphosphonates act as an anti-osteoclast via the induction of osteoclast apoptosis, resulting in a decreased rate of bone resorption. Unfortunately, there is much evidence to demonstrate that the long-term use of bisphosphonates is associated with osteonecrosis. The pathogenesis of osteonecrosis includes the death of osteoblasts, osteoclasts, and osteocytes. In addition, the functions of endothelial cells, epithelial cells, and fibroblasts are impaired in osteonecrosis, leading to disruptive angiogenesis, and delayed wound healing. Osteonecrosis is most commonly found in the jawbone and the term medication-related osteonecrosis of the jaw (MRONJ) has become the condition of greatest clinical concern among patients receiving bisphosphonates. Although surgical treatment is an effective strategy for the treatment of MRONJ, several non-surgical interventions for the attenuation of MRONJ have also been investigated. With the aim of increasing understanding around MRONJ, we set out to summarize and discuss the holistic effects of bisphosphonates on the bone and its surrounding tissues. In addition, non-surgical interventions for the attenuation of bisphosphonate-induced osteonecrosis were reviewed and discussed.

Synthetic Calcium Phosphate Ceramics as a Potential Treatment for Bisphosphonate-Related Osteonecrosis of the Jaw

(1) Background: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is one of the most often seen side effects in patients treated with nitrogen-containing bisphosphonates (BPs), a post-surgical non-healing wound condition. Since calcium phosphate (CP) compounds are able to adsorb zoledronate (ZOL) when used as a drug delivery vehicle, we aimed to verify if these ceramics might have a potential protective effect for soft tissues surrounding surgical osseous wounds. (2) Methods: The chemical reaction between ZOL and CP compounds was evaluated through ultraviolet-visible spectroscopy and elemental analysis. A primary culture of human gingival fibroblasts (HGF) was established as a model to evaluate the cytotoxicity of the association of ZOL (5–500 μM) and of ZOL/biphasic calcium phosphates (BCP). Metabolic activity, cell viability, types of cell death, the cell cycle through, and the migration ability of human gingival fibroblasts were evaluated. (3) Results: ZOL was adsorbed by biphasic calcium phosphate compounds in an aqueous solution. The HGF were sensitive to ZOL toxicity; nevertheless, ZOL/BCP showed a significant protective effect regarding metabolic activity, cell viability, and cell migration. (4) Conclusions: BCP interaction with ZOL reduces or abolishes its toxicity in HGF. This finding represents a potential solution for BRONJ in the case of patients undergoing therapy with ZOL.

Novel insight into the management of bisphosphonate-related osteonecrosis of the jaw (BRONJ)

Bisphosphonate-related osteonecrosis of the jaw (BRONJ), characterized by refractory bone exposure, has recently emerged as a serious side effect of bisphosphonate (BPs) treatment. We discuss novel insights that may help to improve the efficacy of BRONJ treatment and prevention. Our report highlights the following: (1) The presence of exposed bone in patients taking BPs does not necessarily reflect BRONJ, and diagnoses of oral ulceration with bone sequestration and malignancy must be excluded. (2) Osteonecrosis type of BRONJ is difficult to avoid using preventive dental measures alone. However, as with osteomyelitis type of BRONJ, preventive dental measures are indispensable for reducing the risk of secondary infection and disease progression. (3) The importance of tooth extraction as a risk factor for BRONJ among patients taking BPs has been overstated, particularly when they are administered at low doses. Delaying tooth extraction may increase the risk for the onset and progression of osteomyelitic BRONJ. (4) In patients taking low doses of BPs, dental implant surgery is not necessarily contraindicated if there are no other risk factors, such as combined use of corticosteroids or concomitant diabetes. However, the risk of BRONJ due to peri-implantitis must be explained when obtaining patient consent.

Bisphosphonate-induced osteonecrosis of the jaw in patients with bone metastatic, hormone-sensitive prostate cancer. Risk factors and prevention strategies

Aims and background

Evidence from the literature suggests that osteonecrosis of the jaw is emerging as a serious complication of treatment with bisphosphonates for patients with advanced prostate cancer.

Methods and study design

This study is a series of 60 patients with osseous metastases from prostate cancer under complete androgen deprivation therapy. All patients also received bisphosphonates intravenously every 3 to 4 weeks. Over a period of 3 and a half years, we recorded the incidence, presenting signs and symptoms of osteonecrosis of the jaw among those patients and the diagnostic workup required.

Results

Nine of the 60 patients with metastatic prostate cancer were found to be affected with osteonecrosis of the jaw secondary to bisphosphonate administration at the Urology Department at the University Hospital of Alexandroupolis between January 2006 and August 2009. For diagnostic reasons, all 9 patients underwent computed tomography scan and magnetic resonance imaging of the maxillary region, as well as a three-phase whole body bone scan.

Conclusions

There is evidence that administration of bisphosphonates in patients with advanced prostate cancer may increase the risk of osteonecrosis of the jaw. Guidelines regarding the diagnosis and management of those patients are needed.

Chemical and Radiation-Associated Jaw Lesions

Osteonecrosis of the jaw is a major public health concern throughout the world. Use of radiotherapy for head and neck cancer and bone antiresorptives and antiangiogenic agents have increased its incidence. Medication-related osteonecrosis of the jaw is more common relative to other types of osteonecrosis. Osteoradionecrosis occurs despite better treatment planning and shielding to minimize collateral damage to bone. Other related necrotic lesions are secondary to usage of recreational drugs and steroids. This article provides comprehensive information about these different types of bone necrosis; provides the readers with radiographic diagnostic criteria and updates on current theories on pathophysiology of osteonecrosis.

Bisphosphonate-related osteonecrosis of jaws in advanced stage breast cancer was detected from bone scan: a case report

Bisphosphonates (BPs) are indicated to treat skeletal-related events (SREs) for cancer patients with bone metastasis. We report a 79-year-old woman with advanced stage breast cancer with bone metastasis who was prescribed BPs (zoledronate), then developed osteonecrosis of jaw. We provide a brief review of the pathogenesis, diagnosis and treatment of this complication.

Impact of communication between physicians and dentists on the incidence of jaw osteonecrosis caused by bone anti-resorptives

Dental management of osteoporosis patients on anti-resorptive therapy can be challenging for both the dentist and physician because of the risk of osteonecrosis of the jaw (ONJ). This editorial reflects on the paper written by Tagushi et al that expressed a relative lack of communication between health care providers when treating osteoporosis patients. Osteoporosis-related bone fractures can be debilitating and occasionally lethal, but management with anti-resorptives is vital while cognizant of the complication of ONJ that can also negatively impact patient’s quality of life.

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

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

Role of intravenous dosage regimens of bisphosphonates in relation to other aetiological factors in the development of osteonecrosis of the jaws in patients with myeloma

The aim of this case-control study was to identify possible explanatory risk factors for the development of bisphosphonate-related osteonecrosis of the jaws (BRONJ) by estimating the effects of intravenous dosage regimens of bisphosphonates, coexisting diseases, and other drugs on 201 patients with multiple myeloma, with or without BRONJ. We compared sex, treatment with bisphosphonates, incidence of diabetes, and the taking of drugs such as corticosteroids and chemotherapy in patients who had BRONJ (n=44) and patients who did not (n=157). Among the bisphosphonates given intravenously zoledronic acid showed a stronger correlation with BRONJ than pamidronic acid. The risk of developing BRONJ increased dramatically at cumulative intravenous doses of more than 78 mg of zoledronic acid or 600 mg of pamidronic acid, which corresponds to treatment for 18 months or longer. Diabetes mellitus correlated significantly with the development of BRONJ (p=0.01) while there was no correlation with sex, simultaneous treatment with corticosteroids, or chemotherapy. In conclusion, treatment with zoledronic acid, high doses of pamidronic acid, and the coexistence of diabetes mellitus seem to be associated with the development of BRONJ.

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.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Bisphosphonate-related osteonecrosis of the jaw: specificities

Bisphosphonate-related osteonecrosis of the jaws (BRONJ) is a severe complication that has recently emerged in patients treated with intravenous bisphosphonates for malignant diseases. This complication usually presents after a minor local trauma during a dental treatment. Several etiopathogenic mechanisms of this pathological condition have been proposed, but no model can explain all morphological changes observed at the macroscopic and microscopic level. BRONJ is likely to be related to direct toxicity in the bone and soft tissue cells, due to nitrogen-containing bisphosphonates. This review elucidates the clinical indications and mechanism of action of bisphosphonates, reports some clinical diagnostic criteria for BRONJ, describe the histopathological criteria for BRONJ diagnosis, the potential triggering pathways and the available treatment strategies.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Efficacy of a nonsurgical treatment regimen in patients with bisphosphonate-related osteonecrosis of the jaws in Saudi Arabia

Objectives:

The objective of this study was to evaluate the effectiveness of a nonsurgical treatment regimen in the long-term control of necrotic areas of the jaws and pain in such patients.

Methods:

A total of 96 patients suffering from the disease were included in this study. All patients received nonsurgical treatment regimen for 10 days, and repeated every 3 months for 2 years. The size of the osteonecrotic lesions was measured and the pain level was self-assessed with a visual analog scale.

Results:

The patients showed a statistically significant (F = 16.1; p < .01; r² = .95) gradual decrease in the size of exposed bone areas during the nonsurgical therapy (from 12.5 to 8.8 mm). Pain scores ranged from 0 to 3 score scale. Complete resolution of the disease was observed in some patients.

Conclusions:

This conservative nonsurgical treatment regimen seems to provide successful treatment in reduction of the sizes of exposed bone areas in the majority of patients.

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

OBJECTIVE

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

BACKGROUND

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

MATERIAL AND METHODS

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

CONCLUSION

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

Bisphosphonate-related osteonecrosis of the jaw in patients with breast cancer

Bisphosphonate represents a well-established treatment option in the management of metastatic bone disease and bone loss/osteoporosis in women with breast cancer. These drugs reduce osteoclast. Some bisphosphonate also have osteoblastic function leading to a reducted bone turnover and thereby skeletal-related events. The aim of this review is to evaluate the bisphosphonate-related osteonecrosis of the jaw in patients with breast cancer. Based on the proven effect of bone protection during adjuvant endocrine therapy, new treatment guidelines recommend the routine use of bisphosphonates to prevent bone loss during adjuvant therapy, which may likely become the standard practice.

Alendronate attenuates eosinophilic airway inflammation associated with suppression of Th2 cytokines, Th17 cytokines, and eotaxin-2

Bisphosphonates (BPs) have been widely used to treat osteoporosis. They act by inhibiting farnesyl diphosphate synthase in the mevalonate pathway. This resembles the action of statins, whose immune-modulating effect has recently been highlighted. In contrast, the effect of BPs on immune responses has not been elucidated well. In this study, we examined the effect of alendronate (ALN), a nitrogen-containing BP, on allergic airway inflammation in a mouse model. BALB/c mice were sensitized twice with OVA and challenged three times with nebulized OVA to induce eosinophilic airway inflammation. ALN was administered by an intragastric tube before each inhalation. ALN strongly suppressed airway eosinophilia and Th2, as well as Th17 cytokine production in the lung. ALN also attenuated eotaxin-2 production in the lung. Immunohistochemistry demonstrated that the major cell source of eotaxin-2 was peribronchial/perivascular macrophages, and flow cytometrical studies confirmed that ALN decreased eotaxin-2 expression in these macrophages. Furthermore, ALN attenuated eotaxin-2 production from mouse pleural macrophages and human monocyte/macrophage-like THP-1 cells in vitro. These results suggest that ALN suppressed Ag-induced airway responses in the mouse model. The suppression of eotaxin-2 production from macrophages appears to be one of ALN's immunomodulatory effects, whereas the mechanism by which ALN suppressed Th2 and Th17 responses could not be fully elucidated in this study. Although a clinical study should be conducted, ALN could be a novel therapeutic option for asthma.

Case series of 589 tooth extractions in patients under bisphosphonates therapy. Proposal of a clinical protocol supported by Nd:YAG low-level laser therapy

Objective: Trauma during dental surgery is a predisposing factor for bisphosphonates (BP)-related osteonecrosis of the jaws (BRONJ). However, about 40% of cases of BRONJ are not related to dental invasive procedures, being probably associated to endodontic or periodontal infections. Extraction of non-treatable teeth is considered a reliable choice, to improve symptoms and to reduce the risk of BRONJ. Here we report our experience of tooth extractions in patients under oral or intravenous BP therapy. Study Design: Two-hundred and seventeen patients (38 males, 179 females; mean age 68.72 ± 11.26 years, range 30 to 83 years) under BP therapy received 589 tooth extractions at the Unit of Oral Medicine, Pathology and Laser-assisted Surgery of the University of Parma, Italy, between June 2006 and December 2010. Ninety five patients were under BP therapy for oncological disease (multiple myeloma (MM): 23; bone metastases (BM): 72) and 122 patients for non oncological diseases: 119 osteoporosis (OP), 2 rheumatoid arthritis (RA) and 1 Paget’s disease (PD). The mean duration of BP was of 35 months. Antibiotic treatment was administered three days before and 2 weeks after tooth extractions. Patients were additionally treated with low level laser therapy (LLLT) through Nd:YAG laser (1064 nm – power 1.25 W; frequency 15 Hz; fibre diameter: 320 ?m), 5 application of 1 minute each. Patients were evaluated 3 days and once a week for 2 months after the extractions and every time they received LLLT. Mean follow-up was 15 months (ranging from 4 to 31 months). Results: In a total of 589 extractions (285 mandibular, 304 maxillary) performed, a minimal bone exposure was observed in 5 cases, treated with Er:YAG laser vaporization and than healed. Conclusions: Our experience supports the hypothesis that the association of antibiotic treatment and LLLT can be effective in preventing ONJ after tooth extractions in patients under BPT.

Key words:Nd:YAG laser, low level laser therapy, tooth extractions, bisphosphonates, jaws osteonecrosis.

Risks for jaw osteonecrosis drastically increases after 2 years of bisphosphonate therapy

SUBJECTS

This study consisted of 191 patients older than 40 years with osteonecrosis of the jaw (ONJ) drawn from dental practices in the geographic locations of 3 practice-based research networks (PBRNs). Control patients (n = 573) enrolled were individuals older than 40 years without prior history of ONJ. Three control patients were matched with each ONJ case. The ONJ cases originated from primary, secondary, and tertiary care centers. For each ONJ case diagnosed at a primary care center, the 3 matched controls were selected from the same primary care center. However, controls for cases obtained from secondary or tertiary care centers were selected when possible from the general dental practice that referred the case or from another practice in the same geographic area.

KEY RISK/STUDY FACTOR

The key risk factor in this study was bisphosphonate therapy.

MAIN OUTCOME MEASURE

The main outcome measure was ONJ. The definition of ONJ was maxillary or mandibular exposed bone of any size that clinically appeared necrotic, without regard for duration or cause. Therefore, all types of jaw osteonecrotic lesions were included in this study; but patients were limited to those diagnosed with onset of ONJ after January 1, 2003, without prior history of facial trauma or sickle cell disease.

MAIN RESULTS

The results indicate that 83% of cases and 15% of controls received bisphosphonate therapy for a mean duration (standard error) of 5.6 (0.7) and 4.2 (0.6) years, respectively. Therapy with either intravenous or oral bisphosphonates was highly predictive of ONJ; however, intravenous bisphosphonates (odds ratio [OR] = 299.5; 95% confidence interval [CI] = 70.0- 1282.7) were more associated with ONJ than oral bisphosphonates (OR = 9.8; 95% CI = 5.3- 18.1). Risk of developing ONJ existed within the first 2 years and increased fourfold after 2 years of bisphosphonate use (P < .0001).

CONCLUSIONS

The authors concluded that ONJ is causally linked to both intravenous and oral bisphosphonate use, and risk of ONJ escalates tremendously after 2 years of bisphosphonate therapy. The authors also concluded that oral suppuration and dental extractions are independent ONJ risk factors.

Onset of mandible and tibia osteoradionecrosis: a comparative pilot study in the rat

OBJECTIVES

Osteoradionecrosis (ORN) is common in the jaws after radiotherapy. We hypothesized that the mandible is more susceptible to ORN than the tibia, based on site disparity in hypoxic, hypocellular, and hypovascular tissue breakdown.

STUDY DESIGN

Twelve rats received 50 Gy irradiation to mandible or tibia; 4 of the rats further received minor surgical trauma to the irradiated sites. Structural and cellular skeletal changes were assessed with computerized tomography, histology, and immunostaining.

RESULTS

Mandible developed ORN with 70% mean bone loss 10 weeks after irradiation (P < .05), whereas tibia was structurally and radiologically intact 20 weeks after irradiation. Hypocellularity, hypoxia, and oxidative stress were higher in irradiated mandible (P < .001) than tibia (P < .01) but vascular damage was similar at both skeletal sites. Combined effects of radiation and minor trauma promoted mandibular alveolar bone loss and tibial fracture.

CONCLUSIONS

ORN has a more rapid onset in mandible than in tibia in the rat.

Bisphosphonate induced osteonecrosis of jaw in breast cancer patients: A systematic review

BACKGROUND

Bisphosphonate therapy is widely used for the treatment of bone metastasis in breast cancer patients.

AIM

The aim of this study is to estimate the overall prevalence of bisphosphonate induced osteonecrosis of jaw (BONJ) in breast cancer patients with bone metastasis.

MATERIALS AND METHODS

A literature review was conducted to search and evaluate all the articles that contained original data on the prevalence of BONJ in breast cancer patients from the year 2003-2009. Pubmed search terms used were bisphosphonate, osteonecrosis, breast cancer and jaw. Eleven publications that fulfilled the inclusion criteria were chosen for the study. Case reports and reviews were excluded from the analysis based on assessing the title and abstract.

RESULTS

Of the 2490 breast cancer patients, 69 developed BONJ with the overall prevalence rate of 2.8%. All the patients with BONJ had received zoledronate or pamidronate, either alone or in combinations.

CONCLUSION

BONJ is a significant complication occurring in 2.8% of the breast cancer patients receiving bisphosphonates for metastatic bone disease. It is very important to identify the trigger factors associated with BONJ and also to establish guidelines for the prevention and effective treatment of this condition.

Laser GaAlAs (λ860 nm) photobiomodulation for the treatment of bisphosphonate-induced osteonecrosis of the jaw

OBJECTIVE

The aim of this article is to report a case of bisphosphonate-induced osteonecrosis (ONJ-BP) of the jaw treated by curettage of the necrotic bone, low-level laser therapy (LLLT), and antibiotic therapy.

BACKGROUND DATA

ONJ-BP is characterized by painful ulcerations of the oral mucosa, is prone to bone necrosis that does not heal within 8 weeks after diagnosis, and is often difficult to treat. No definitive standard of care has been established for ONJ-BP. LLLT improves wound healing, relieves pain, and appears to be a promising treatment modality for patients with ONJ-BP.

MATERIALS AND METHODS

An 82-year-old man taking intravenous bisphosphonate presented with ONJ-BP after tooth extraction. The patient was treated by LLLT using a GaAlAs diode laser with the following settings: wavelength, 860 nm; 70 mW; continuous wave; and spot size 4 mm(2). An energy density of 4.2 J/cm(2) per point was applied in a punctual contact manner every 48 h for 10 days, in association with antibiotic therapy and curettage of the necrotic bone. Reduction in painful symptoms was reported after the second irradiation session, and tissue healing was complete at the end of the third week following oral curettage. The patient was followed up for 12 months and exhibited good oral healt and quality of life.

CONCLUSIONS

The therapeutic protocol used in this study had a positive effect on tissue healing and remission of painful symptoms, resulting in better oral health and quality of life for the patient.

Patient-related risk factors for implant therapy. A critique of pertinent literature

BACKGROUND

Treatment planning for dental implants involves the assessment of patient-related risk factors prior to formulation of a treatment plan. The aim of this review was to assess relevant literature and provide evidence-based information on the successful surgical placement of dental implants.

METHODS

An electronic search of Medline, PubMed and the Cochrane Databases of Systematic Reviews was undertaken using a combination of MeSH terms and keywords. A handsearch was also performed and cross-referenced with articles cited in papers selected. The primary study parameter was implant failure.

RESULTS

Forty-three studies were selected based on specific inclusion criteria. Many studies contain confounding variables, numbers in subcategories are often too small for meaningful statistical analysis, and follow-up times vary and are often short-term.

CONCLUSIONS

There are many risk factors which the clinician is required to know and understand to advise patients, and consider in planning and treatment provision. Consistent evidence exists to show an increased failure rate with smokers, a history of radiotherapy and local bone quality and quantity. Weaker evidence exists to show a higher incidence of peri-implant disease in patients with a history of periodontitis-related tooth loss. Lack of evidence precludes definitive guidelines for patients with autoimmune disorders where expert opinion recommends caution. Osteoporotic patients show acceptable survival rates; however patients on oral bisphosphonates show a small incidence but high morbidity from osteonecrosis of the jaw. Emerging evidence suggests that there is a correlation between genetic traits and disruption of osseointegration.

Emerging novel therapies in the treatment of castrate-resistant prostate cancer

The treatment options for patients with castration-resistant prostate cancer (CRPC), until very recently, only included docetaxel. In the past 10 months, newly Federal Drug Administration (FDA) approved agents in the United States have shown survival benefit for patients with CRPC. This review takes a closer look at these newer agents: sipuleucel-T (immune therapy) and cabazi-taxel (cytotoxic therapy). We also review the evidence supporting the FDA's approval of denosumab (bone-targeted therapy) as a treatment option for men with CRPC and bony metastases. Newer agents currently being investigated in phase III clinical trials for their potential role in metastatic CRPC are also reviewed. These agents include abiraterone (hormonal therapy), TAK-700 (hormonal therapy), MDV3100 (hormonal therapy), ipilimumab (immune therapy), zibotentan (endothelin-A receptor antagonist) and dasatinib (tyrosine kinase inhibitor). As ongoing studies using all the aforementioned agents continue to evolve, our understanding of how and where these agents fit into the treatment paradigm for patients with CRPC will become clearer.

Current management of castrate-resistant prostate cancer

Prostate cancer (PCa) is the most frequently diagnosed cancer in North America. Castrate-resistant PCa presents a spectrum of disease ranging from rising PSA levels in the absence of metastases or symptoms and despite androgen-deprivation therapy, to metastases and significant debilitation from cancer symptoms. Castrate-resistant PCa is usually suspected in patients with new symptoms on androgen deprivation therapy, with a rising PSA, or with new evidence of disease on bone scans or computed tomography scans. Institution of treatment and the choice of systemic or local therapy depend on a number of factors. This review discusses the various currently available treatments for patients with castrate-resistant PCa, from secondary hormonal manipulations to options for post-docetaxel systemic therapy.

Osteonecrosis of the posterior mandible after implant insertion: a clinical and histological case report

BACKGROUND

In the past few years, the occurrence of an oral lesion, called osteonecrosis of the jaw (ONJ), has been increasingly reported in patients undergoing treatment with bisphosphonates (BPs); however, few published histological studies of ONJ can be found in the literature.

PURPOSE

The aim of the present case was to report an occurrence of ONJ after implant insertion.

MATERIALS AND METHODS

Multiple myeloma was diagnosed to a 65-year-old female. After 5 years of treatment with intravenous clodronate, two dental implants were inserted in the mandibular molar region. No preexisting bone lesions were present at a preoperative panoramic radiography. Before implant insertion, the patient had suspended the treatment with clodronate for 3 months. Four months after the implant insertion, a breakdown of the oral mucosa covering the implants occurred with a purulent discharge; periapical radiolucency was present around both implants. An en-block resection on the alveolar bone including the two implants was performed. No signs of recurrence of the lesion were observed after a follow-up of 20 months.

RESULTS

At the interface of one of the implants, a gap was observed between bone and implant. This bone was nonvital, and many osteocyte lacunae were empty. Moreover, this bone appeared to be partially demineralised. No newly formed bone or osteoblasts were present. Bone trabeculae were observed, on the other hand, within the apical implant threads of the other implant. A close connection was observed between this bone and the implant surface.

DISCUSSION

The histological findings showed some areas with osseointegration in patients undergoing BP treatment for malignant disease; however, any invasive procedure can determine the onset of osteonecrosis.

CONCLUSION

In conclusion, there is certainly a temporal association between BP use and development of ONJ, but a correlation does not necessarily mean causation. Moreover, generalizations about this complex relationship cannot be made on the basis of a single case report. In patients undergoing intravenous treatment, clinicians must be aware of the increased risk of implant failure and, probably, implant insertion should be avoided at all until more conclusive data are available.