A retrospective study of osteomyelitis and osteonecrosis of the jaws and its etiologic implication of bisphosphonate in Asians

Porphyromonas gingivalis Induces Bisphosphonate-Related Osteonecrosis of the Femur in Mice

One of the most prominent characteristics of bisphosphonate-related osteonecrosis of the jaw(BRONJ) is its site-specificity. Osteonecrosis tends to occur specifically in maxillofacial bones, in spite of a systemic administration of the medicine. Previous studies suggested rich blood supply and fast bone turnover might be reasons for BRONJ. Yet, a sound scientific basis explaining its occurrence is still lacking. The present study aimed to explore the role of Porphyromonas gingivalis (P. gingivalis), an important oral pathogen, on the site-specificity of bisphosphonate-induced osteonecrosis and to elucidate its underlying mechanism. Mice were intraperitoneally injected with zoledronic acid (ZA) or saline for 3 weeks. In the third week, the right mandibular first molars were extracted and circular bone defects with a diameter of 1 mm were created in right femurs. After the operation, drug administration was continued, and P. gingivalis suspension was applied to the oral cavities and femur defects. The mice were killed after four or eight weeks postoperatively. The right mandibles and femurs were harvested for micro-CT and histological analyses. A poor healing of bone defects of both jaws and femurs was noted in mice injected with both ZA and P. gingivalis. Micro-CT analysis showed a decreased bone volume, and histological staining showed an increased number of empty osteocyte lacunae, a decreased collagen regeneration, an increased inflammatory infiltration and a decreased number of osteoclasts. In addition, the left femurs were collected for isolation of osteoclast precursors (OCPs). The osteoclastogenesis potential of OCPs was analyzed in vitro. OCPs extracted from mice of ZA-treated groups were shown to have a lower osteoclast differentiation potential and the expression level of related genes and proteins was declined. In conclusion, we established a mouse model of bisphosphonate-related osteonecrosis of both the jaw and femur. P. gingivalis could inhibit the healing of femur defects under the administration of ZA. These findings suggest that P. gingivalis in the oral cavity might be one of the steering compounds for BRONJ to occur.

Is teriparatide therapy effective for medication-related osteonecrosis of the jaw? A systematic review and meta-analysis

Considering the lack of studies determining the real TPTD efficacy in individuals who develop MRONJ, our objective was to combine the available data on MRONJ cases treated with TPTD. The findings demonstrated that TPTD in combination with another therapy, especially antibiotic therapy, can be considered an effective protocol for MRONJ.

PURPOSE

To integrate the data published on the effect of teriparatide (TPTD) therapy on cases of medication-related osteonecrosis of the jaws (MRONJ) into a comprehensive analysis of clinical features.

METHODS

An electronic search was undertaken in six databases. Descriptive analyses of clinicodemographic data of MRONJ were carried out. Poisson regression was also run to evaluate predictors of total resolution of MRONJ treated with TPTD.

RESULTS

Twenty-six publications comprising 111 cases were included. Most reported cases affected female individuals (82.0%) with a mean age of 76.54 years. Osteoporosis (76.5%) represented the main reason for using antiresorptive drugs, with bisphosphonates (98.1%) as the most frequently reported. Comorbidities were commonly present. The most related trigger factor of MRONJ was dental extraction (61.7%). Mandible (75.8%) was the most commonly affected site, with a mean evolution time of 5 months. MRONJ stage 2 (61.3%) was the most prevalent. Regarding TPTD treatment, in 45.1% cases, TPTD was used alone, with the total resolution being observed in 59.5% of the individuals. Associated therapy (54.9%) included surgery, antibiotic therapy, and laser therapy. Mean follow-up was 8.7 months. Poisson regression demonstrated that individuals with MRONJ stage 1 were 1.21 times more likely to present total resolution of osteonecrosis than individuals with MRONJ stage 3 (CI = 1.02-1.43; p < 0.023). Individuals who had undergone treatment with TPTD in association with another therapeutic modality were 1.21 times more likely to present total resolution of osteonecrosis than those who had undergone treatment with TPTD alone (CI = 1.40-1.39; p < 0.010).

CONCLUSION

TPTD in combination with another therapy, especially antibiotic therapy, should be considered an effective therapeutic modality for MRONJ.

Analysis of medication-related osteonecrosis of the jaw with bone SPECT/CT: relationship between patient characteristics and maximum standardized uptake value

Objective:

To analyze medication-related osteonecrosis of the jaw (MRONJ) with bone single photon emission computed tomography (SPECT)/CT, especially relationship between patient characteristics and maximum standardized uptake value (SUV).

Methods:

48 patients with MRONJ who underwent bone SPECT/CT were prospectively included. MRONJ patients were included 34 osteoporosis and 14 bone metastases from 6 lung cancer, 6 breast cancer and 2 rectal cancer. The maximum SUV of the MRONJ patient characteristics were analyzed such as gender, location, underlying disease, medication and staging of MRONJ by Mann–Whitney U test. P-values lower than 0.05 indicate significant differences.

Results:

Regarding underlying disease, maximum SUV of patients with osteoporosis (18.69 ± 8.57) were significantly higher than those with bone metastases (12.28 ± 4.32, p = 0.005). Furthermore, maximum SUV of MRONJ was a significant difference for medication (denosumab: 13.62 ± 5.70 and minodronate: 22.98 ± 11.73, p = 0.009) and staging of MRONJ (Stage 2: 15.59 ± 8.06 and Stage 3: 21.51 ± 7.15, p = 0.014).

Conclusion:

Maximum SUV assessed by SPECT/CT was significantly increased in MRONJ patients with osteoporosis and Stage 3. Bone SPECT/CT could be an effective tool for the analysis of MRONJ.

Effect of bisphosphonates on healing of tooth extraction wounds in infectious osteomyelitis of the jaw

OBJECTIVES

Antiresorptive agent-related osteonecrosis of the jaw (ARONJ) and infectious osteomyelitis of the jaw (OMJ) in antiresorptive-naïve patients are different disease entities. Although osteoclast inhibition is at the center of the pathogenesis of ARONJ, the role of osteoclast inhibition in infectious OMJ is unknown. The objective of this study was to determine the effect of bisphosphonate osteoclast inhibition in infectious OMJ.

METHODS

Osteomyelitis was induced in mice by S. aureus inoculation. The establishment of OMJ was verified by the culture of bone marrow samples obtained from the mandible. Infected animals received either zoledronic acid (ZA) or saline starting at week-2. Treated animals along with non-infected animals underwent tooth extractions at week-4 post-infection. Healing was assessed every week using in vivo micro-computed tomography and intraoral photos. Animals were euthanized at week-8 and cervical lymph nodes were assessed for lymphatic and blood vessels.

RESULTS

Tooth extraction wounds did not heal in animals with OMJ. These wounds were characterized by incomplete soft tissue coverage, sporadic bone fill in the sockets, and inflammatory cell accumulation in the connective tissue at 4 weeks after tooth extractions. Conversely, the majority of tooth extraction wounds in the infected animals treated with ZA had improved healing with better bone fill than even non-infected control animals. Consistently, atrophic lymphatic vessels were noted in the draining lymph nodes in animals with OMJ. However, infected animals treated with ZA had lymphatic vessels that were unaltered and showed a similar appearance to those in non-infected control animals.

CONCLUSION

ZA treatment promoted wound healing in the jaw with infectious osteomyelitis. Clearly, antiresorptive therapy is contraindicated in patients with ARONJ. However, our finding suggests that osteoclast inhibition is potentially an effectual remedy for infectious OMJ in antiresorptive-naïve patients.

Is implant surgery a risk factor for osteonecrosis of the jaw in older adult patients with osteoporosis? A national cohort propensity score-matched study

OBJECTIVES

This study aimed to investigate the association between dental implant therapy and osteonecrosis of the jaw (ONJ) in osteoporotic patients and the relationship between tooth extraction, dental implantation, and ONJ.

MATERIAL AND METHODS

This retrospective cohort study used the Customized Health Information Data from the National Health Insurance Corporation in South Korea. The study population included patients older than 70 years with a history of osteoporosis; the cases included patients who had undergone dental implant surgery between July 2014 and July 2016 with specific procedure codes. The case and control cohorts were stratified by tooth extraction because it was the strongest risk factor to consider in this study. Each group of patients was matched using the propensity score. To investigate the relationship between dental implants and ONJ, a Cox proportional hazard model was applied to socio-economic factors, comorbidities, and bisphosphonates (BPs). All analyses were conducted using SAS statistical software.

RESULTS

Based on the fully adjusted model, the propensity score-matched osteoporosis patients with dental implants had a 0.51 times hazard ratio of osteonecrosis. On the contrary, tooth extraction was associated with a higher risk of ONJ (HR = 5.89). The patients with rheumatoid arthritis (RA) and those using BPs had a higher HR, respectively, 6.80 and 4.09 HR (p < .001).

CONCLUSIONS

Dental implantation was not a risk factor and patients with implants show rather lower ratios. However, older osteoporotic Korean patients who had undergone tooth extraction had higher risks of ONJ. A significantly higher risk of ONJ was associated with RA and BPs as well.

Clinical profile of individuals with bisphosphonate-related osteonecrosis of the jaw: an integrative review

BACKGROUND

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is still the most prevalent type of osteonecrosis with clinical relevance. In Brazil, bisphosphonate use is high but there is a lack of epidemiological studies on BRONJ.

OBJECTIVE

To determine the clinical profile of BRONJ in a Brazilian population through an integrative review.

DESIGN AND SETTING

Integrative review of BRONJ in a Brazilian population.

METHODS

Cases and clinical research on Brazilians with BRONJ between 2010 and 2019, indexed in PubMed/MEDLINE, Scopus, Web of Science and LILACS were reviewed. Age, sex, type and time of bisphosphonate intake, administration route, related diseases, region of the BRONJ, diagnostic criteria, staging, triggering factor and type of treatment were analyzed.

RESULTS

Fifteen articles on 128 subjects were included. Most patients were women (82.03%); the mean age was 63 years. Intravenous zoledronic acid was mostly used (62.50%), for breast cancer treatment (46.87%). The main localization of BRONJ was the mandible (54.68%), associated mainly with tooth extractions (45.98%). The diagnostic criteria were clinical (100%) and radiographic (89.06%), mostly in stage II (68.08%). The surgical treatments were sequestrectomy (37.50%) and platelet-rich plasma (PRP) (36.71%). Microbial control was done using chlorhexidine (93.75%) and infection control using clindamycin (53.90%).

CONCLUSIONS

BRONJ had higher prevalence in Brazilian women receiving treatment for breast cancer and osteoporosis. The mandible was the region most affected with a moderate stage of BRONJ, particularly when there were histories of tooth extraction and peri-implant surgery. Sequestrectomy with additional drugs and surgical therapy was the treatment most accomplished.

Refractory healing after surgical therapy of osteonecrosis of the jaw: associated risk factors in aged patients

Purpose: Osteonecrosis of the jaw (ONJ), both medication-related and non medication-related, mainly occurs in aged patients. It needs surgical intervention. Refractory healing after an operation of ONJ can significantly lower the quality of life of elderly patients. The purpose of this study was to determine risk factors associated with refractory healing in aged patients.

Patients and methods: We performed a retrospective study of ONJ in aged patients who underwent surgical treatments in a single institute during a 12-year period. Multiple logistic regression analysis was used to determine independent risk factors associated with refractory healing.

Results: A total of 122 patients were included. Of them, 25 patients were identified as the refractory group and 97 patients as the control group. Diabetes mellitus (DM) (AOR=5.03, 95% CI: 1.74–14.52) and glucocorticoid administration (AOR=7.97, 95% CI: 2.52–25.23) were found to be significant risk factors for refractory healing of ONJ.

Conclusion: DM and medication of glucocorticoid might be risk factors for refractory healing of ONJ.

Infected Cemento-Osseous Dysplasia: Analysis of 66 Cases and Literature Review

The aim of this study was to describe a series with 66 cases of infected cemento-osseous dysplasia (COD) and to discuss the demographic distribution, clinicoradiographic features and treatment of this condition. A study looking back on the diagnoses made at a single Brazilian centre within a 28-year timeframe was performed. A literature review with searches across five databases was also conducted to identify reports on osteomyelitis/infected COD. Descriptive and statistical analyses were performed. The case series study showed a female/male ratio of 21:1. Affected individuals' mean age was 57.4 years. Mandible was the most affected site (95.5%) and florid subtype was the most frequent infected COD (62.1%). Tooth extraction was the main factor associated with the development of infection associated within a COD lesion. The literature review retrieved 30 studies reporting 46 cases of this condition. Asian women in their 40 s and 50 s were more affected. Surgery for removal/curettage of necrotic bone was acknowledged as an appropriate approach to the treatment of this infection. The clinicodemographic data of the study were similar to data collected across the literature. Clinicians, maxillofacial surgeons and oral rehabilitation providers should be alert to the diagnosis of COD, since infection is a frequent complication whose management is challenging.

Osteoporosis therapy in patients with inflammatory rheumatic diseases and osteonecrosis of the jaw

BACKGROUND AND OBJECTIVES

The aim of the present study was to assess the prevalence of medication-related osteonecrosis of the jaw (MRONJ) in osteoporosis patients suffering from inflammatory rheumatic diseases, as well as to assess the prevalence of relevant dental, behavioral, and medical risk factors for MRONJ.

MATERIALS AND METHODS

A total of 198 patients with inflammatory rheumatic diseases and osteoporosis therapy were recruited from a tertiary rheumatological/immunological referral center between June 2015 and September 2016. They were assessed using a structured interview. A maxillofacial surgeon later examined patients complaining of possible symptoms of osteonecrosis. In cases of osteonecrosis, dental records were obtained and evaluated. Preventive measures taken and dental as well as other clinical risk factors were evaluated.

RESULTS

Of the 198 patients, three suffered from osteonecrosis of the jaw, none of whom had any history of malignant disease or radiation therapy, resulting in a prevalence of 1.5%. Of these three patients, only one was given bisphosphonates intravenously (i.v.), whereas all three had been treated orally. All three diagnoses of MRONJ had been previously known to the patients and their maxillofacial surgeons. Two of the patients had rheumatoid arthritis, and one patient suffered from large vessel vasculitis. Long anti-osteoporotic treatment duration, low functional status, and low bone density of the femur were significantly associated with MRONJ development.

CONCLUSION

Inflammatory rheumatic diseases constitute a risk factor for MRONJ in patients treated with bisphosphonates for osteoporosis. Patients should be counseled accordingly and should be offered dental screening and regular dental check-ups.

Drug holiday patterns and bisphosphonate-related osteonecrosis of the jaw

OBJECTIVES

There is limited evidence regarding the appropriate length of a bisphosphonate (BP) holiday to reduce the risk of osteonecrosis of the jaw (ONJ). In this cross-sectional study, we investigated the population-based patterns of the gaps between BP discontinuation and ONJ diagnosis.

SUBJECTS AND METHODS

We used the claims database of the National Health Insurance Service in Korea. Among BP users between 2006 and 2015, incident ONJ cases during 2010-2015 with no history of ONJ in the last 4 years were identified. We assessed the time gap from the last BP administration to ONJ diagnosis.

RESULTS

Among 1,569 incident ONJ cases, 836 (53.3%) occurred after BP discontinuation. The cumulative proportions of ONJ occurrence within 1 month, 3 months, 1 year, 2 years, and 3 years after discontinuation were 58.9%, 70.8%, 87.0%, 93.2%, and 96.1%, respectively. The length of drug holidays showed no significant difference between patients with or without comorbid cancer and diabetes mellitus (p-value, 0.12 and 0.52, respectively). However, the use of injectable BP formulations significantly affected ONJ incidence (p < 0.01).

CONCLUSIONS

Most ONJ cases occurred within 3 years from BP suspension, with a higher prevalence among BP injection users with 1 year or lesser BP holiday.

Treatment with anti-Sclerostin antibody to stimulate mandibular bone formation

BACKGROUND

Anti-Sclerostin antibody (Scl-Ab) is a promising new bone anabolic therapy. Although anti-Scl-Ab stimulates bone formation and repair in the appendicular and axial skeleton, its efficacy in the craniofacial skeleton is still poorly understood.

METHODS

Using an established model of Down syndrome-dependent bone deficiency, 10 Ts65Dn mice and 10 wild-type mice were treated weekly via i.v. tail vein injection with vehicle or anti-Sclerostin for 3 weeks and euthanized 1 week after.

RESULTS

Wild-type mice treated with the anti-Scl-Ab had increased mandibular bone, trabecular thickness, and alveolar height compared with controls. Anti-Scl-Ab increased Ts65Dn mandibular bone parameters such that they were statistically indistinguishable from those in vehicle-treated wild-type mandibles.

CONCLUSION

Treatment with anti-Scl-Ab significantly increased mandibular bone mass and alveolar height in wild type mice and normalized mandibular bone mass and alveolar height in Ts65Dn mice. The anti-Scl-Ab therapy represents a novel method for increasing mandibular bone formation.