BACKGROUND: Osteogenesis imperfecta (OI) is a group of connective tissue disease characterized by propensity to fractures following minimal trauma. OI is a lifelong inheritable disease and currently has no definitive cure. Management goals are directed towards prevention of fractures, controlling the symptoms, maximizing independent mobility, and developing optimal bone mass and muscle strength. Bisphosphonates are the mainstay of pharmacologic fracture-prevention therapy for most forms of OI. The University of the Philippines-Philippine General Hospital Bisphosphonate Treatment Program for OI was started in 2006 by the Clinical Genetics Service. For more than a decade now, the program has been serving more than 50 OI patients. This study evaluated the clinical outcomes of the patients who were included in the program to add to the body of knowledge on Filipino patients with OI. OBJECTIVES: This study sought to determine the clinical outcomes of children with OI on intravenous pamidronate treatment at the Philippine General Hospital (PGH) from January 2010 to December 2018. METHODS: The study utilized a retrospective review of medical records of 24 patients diagnosed with OI on pamidronate therapy seen at the PGH from January 2010 to December 2018. Descriptive statistics were used to summarize the demographic and baseline clinical characteristics of the patients. Median annualized fracture rates before and during treatment were calculated and compared. The patient functional mobility before and during pamidronate infusion was classified accordingly based on the Gross Motor Function Classification System (GMFCS) and were compared. RESULTS: Twenty-four patients, which include seven males and 17 females, with ages at the time of conduct of the study ranging from four years to 11 years, fulfilled the inclusion criteria. There were four patients with OI type I, six with OI type III, 11 with OI type IV and three with OI type V. The annualized long bone fracture rate decreased significantly from a median of 2.0/year (range 1-2.75) to 0.75/year (range 0-1) after more than a year on pamidronate infusion (p < 0.001). There is a note of overall improvement in terms of functional mobility using the 5-point scale of the GMFCS during pamidronate infusion from the baseline. However, the difference is not statistically significant. CONCLUSION Cyclic intravenous pamidronate treatment in young children with moderate-severe OI is well tolerated and associated with reduced fracture frequency with a tendency to improvement of gross functional mobility.
Human ; Osteogenesis Imperfecta ; Bisphosphonate ; Diphosphonates

BACKGROUND

Osteogenesis imperfecta (OI) is a group of connective tissue disease characterized by propensity to fractures following minimal trauma. OI is a lifelong inheritable disease and currently has no definitive cure. Management goals are directed towards prevention of fractures, controlling the symptoms, maximizing independent mobility, and developing optimal bone mass and muscle strength. Bisphosphonates are the mainstay of pharmacologic fracture-prevention therapy for most forms of OI. The University of the Philippines-Philippine General Hospital Bisphosphonate Treatment Program for OI was started in 2006 by the Clinical Genetics Service. For more than a decade now, the program has been serving more than 50 OI patients. This study evaluated the clinical outcomes of the patients who were included in the program to add to the body of knowledge on Filipino patients with OI.

This study sought to determine the clinical outcomes of children with OI on intravenous pamidronate treatment at the Philippine General Hospital (PGH) from January 2010 to December 2018.

The study utilized a retrospective review of medical records of 24 patients diagnosed with OI on pamidronate therapy seen at the PGH from January 2010 to December 2018. Descriptive statistics were used to summarize the demographic and baseline clinical characteristics of the patients. Median annualized fracture rates before and during treatment were calculated and compared. The patient functional mobility before and during pamidronate infusion was classified accordingly based on the Gross Motor Function Classification System (GMFCS) and were compared.

Twenty-four patients, which include seven males and 17 females, with ages at the time of conduct of the study ranging from four years to 11 years, fulfilled the inclusion criteria. There were four patients with OI type I, six with OI type III, 11 with OI type IV and three with OI type V. The annualized long bone fracture rate decreased significantly from a median of 2.0/year (range 1-2.75) to 0.75/year (range 0-1) after more than a year on pamidronate infusion (pCONCLUSION

Cyclic intravenous pamidronate treatment in young children with moderate-severe OI is well tolerated and associated with reduced fracture frequency with a tendency to improvement of gross functional mobility.

Osteonecrosis of the mandible is also called avascular necrosis of the jaw, and it is a rare complication of bisphosphonates. It is characterized with pain, swelling, exposure of bone, local infection and pathologic fractures of the jaw. With the widespread usage of bisphosphonates in bone metastasis of malignant tumors and osteoporosis, this rare complication has received more attention in recent years. Here, we reported a case of bisphosphonates-related osteonecrosis of the jaw (BRONJ) caused by intravenous zoledronic acid for osteoporosis. A 62-year-old female patient with 7-year history of Sjögren's syndrome and 3-year history of osteoporosis developed BRONJ after 3-year treatment of zoledronic acid. Two months before she went to the Peking University International Hospital, she visited the dentist for periodontal purulent secretion and extracted one tooth from the right mandible. However, the condition was not improved and she felt persistent pain and swelling in the right mandible. Hence, she received repeated root curettage, but there was no improvement. Finally, she was diagnosed with osteonecrosis of the mandible based on the digital volume tomography scan, which showed right mandibular osteonecrosis bone destruction. She underwent surgical debridement of the necrotic bone and administered intravenous antibio-tics at the Peking University International Hospital. Histopathological analysis of the bone biopsy further confirmed the diagnosis of BRONJ. Her condition was improved successfully during a 3-year follow-up. Osteonecrosis of the mandible become more common with the increased use of bisphosphonates. Recent study has reported that osteonecrosis of the mandible is more likely to occur in patients with Sjögren's syndrome. In addition, age, long-term and irregular administration of glucocorticoids, irregular oral examination and treatment also might be the risk factors in the pathogenesis of osteonecrosis of the mandible. For the elder osteoporosis patients who would receive or had received bisphosphonate-related drugs, oral health status and the disease states associated with necrosis of the mandible such as Sjögren's syndrome should be comprehensively measured and fully evaluated during the whole process. Furthermore, to better understand and prevent or reduce the occurrence of this complication, we reviewed the patho-genesis, diagnosis, treatment, and prevention of BRONJ.
Humans ; Female ; Middle Aged ; Bisphosphonate-Associated Osteonecrosis of the Jaw/etiology* ; Diphosphonates/administration & dosage* ; Zoledronic Acid ; Imidazoles/administration & dosage* ; Bone Density Conservation Agents/adverse effects* ; Osteoporosis/drug therapy*

Bisphosphonates(BP),a class of commonly used medications for treating osteoporosis and bone malignancies,significantly affect bone metabolism.When dental implants are placed in patients receiving BP,the potential impacts of BP on the formation and long-term maintenance of implant osseointegration cannot be ignored.In addition,the influence of dental implants on the occurrence of BP-related osteonecrosis of the jaw is garnering attention.This article explores the influences of BP on the stability of dental implants based on a review of previous animal and clinical studies,discusses the impact of dental implants on the occurrence of BP-related osteonecrosis of the jaw,and proposes suggestions for the dental implant treatment of patients taking BP in clinical practice.This review is expected to provide a theoretical basis for the related research and clinical treatment.
Humans ; Dental Implants ; Animals ; Diphosphonates/pharmacology* ; Osseointegration/drug effects* ; Bisphosphonate-Associated Osteonecrosis of the Jaw

Bacterial infection is a common finding in patients, who develop medication-related osteonecrosis of the jaw (MRONJ) by the long-term and/or high-dose use of anti-resorptive agents such as bisphosphonate (BPs). However, pathological role of bacteria in MRONJ development at the early stage remains controversial. Here, we demonstrated that commensal microbiota protects against MRONJ development in the pulp-exposed periapical periodontitis mouse model. C57/BL6 female mice were treated with intragastric broad-spectrum antibiotics for 1 week. Zoledronic acid (ZOL) through intravenous injection and antibiotics in drinking water were administered for throughout the experiment. Pulp was exposed on the left maxillary first molar, then the mice were left for 5 weeks after which bilateral maxillary first molar was extracted and mice were left for additional 3 weeks to heal. All mice were harvested, and cecum, maxilla, and femurs were collected. ONJ development was assessed using μCT and histologic analyses. When antibiotic was treated in mice, these mice had no weight changes, but developed significantly enlarged ceca compared to the control group (CTL mice). Periapical bone resorption prior to the tooth extraction was similarly prevented when treated with antibiotics, which was confirmed by decreased osteoclasts and inflammation. ZOL treatment with pulp exposure significantly increased bone necrosis as determined by empty lacunae and necrotic bone amount. Furthermore, antibiotics treatment could further exacerbate bone necrosis, with increased osteoclast number. Our findings suggest that the commensal microbiome may play protective role, rather than pathological role, in the early stages of MRONJ development.
Animals ; Bisphosphonate-Associated Osteonecrosis of the Jaw/prevention & control* ; Bone Density Conservation Agents ; Diphosphonates ; Female ; Humans ; Mice ; Microbiota ; Periapical Diseases ; Zoledronic Acid

The significant clinical feature of bisphosphonate-related osteonecrosis of the jaw (BRONJ) is the exposure of the necrotic jaw. Other clinical manifestations include jaw pain, swelling, abscess, and skin fistula, which seriously affect the patients' life, and there is no radical cure. Thus, new methods need to be found to prevent the occurrence of BRONJ. Here, a novel nanoparticle, tFNA-KLT, was successfully synthesized by us, in which the nanoparticle tetrahedral framework nucleic acid (tFNA) was used for carrying angiogenic peptide, KLT, and then further enhanced angiogenesis. TFNA-KLT possessed the same characteristics as tFNA, such as simple synthesis, stable structure, and good biocompatibility. Meanwhile, tFNA enhanced the stability of KLT and carried more KLT to interact with endothelial cells. First, it was confirmed that tFNA-KLT had the superior angiogenic ability to tFNA and KLT both in vitro and in vivo. Then we apply tFNA-KLT to the prevention of BRONJ. The results showed that tFNA-KLT can effectively prevent the occurrence of BRONJ by accelerating angiogenesis. In summary, the prepared novel nanoparticle, tFNA-KLT, was firstly synthesized by us. It was also firstly confirmed by us that tFNA-KLT significantly enhanced angiogenesis and can effectively prevent the occurrence of BRONJ by accelerating angiogenesis, thus providing a new avenue for the prevention of BRONJ and a new choice for therapeutic angiogenesis.
Angiogenic Proteins/therapeutic use* ; Bisphosphonate-Associated Osteonecrosis of the Jaw/prevention & control* ; Endothelial Cells ; Humans ; Nanoparticles ; Nucleic Acids/therapeutic use*

Medication-related osteonecrosis of the jaw (MRONJ) is primarily associated with administering antiresorptive or antiangiogenic drugs. Despite significant research on MRONJ, its pathogenesis and effective treatments are still not fully understood. Animal models can be used to simulate the pathophysiological features of MRONJ, serving as standardized in vivo experimental platforms to explore the pathogenesis and therapies of MRONJ. Rodent models exhibit excellent effectiveness and high reproducibility in mimicking human MRONJ, but classical methods cannot achieve a complete replica of the pathogenesis of MRONJ. Modified rodent models have been reported with improvements for better mimicking of MRONJ onset in clinic. This review summarizes representative classical and modified rodent models of MRONJ created through various combinations of systemic drug induction and local stimulation and discusses their effectiveness and efficiency. Currently, there is a lack of a unified assessment system for MRONJ models, which hinders a standard definition of MRONJ-like lesions in rodents. Therefore, this review comprehensively summarizes assessment systems based on published peer-review articles, including new approaches in gross observation, histological assessments, radiographic assessments, and serological assessments. This review can serve as a reference for model establishment and evaluation in future preclinical studies on MRONJ.
Animals ; Bisphosphonate-Associated Osteonecrosis of the Jaw/drug therapy* ; Bone Density Conservation Agents/adverse effects* ; Diphosphonates/therapeutic use* ; Humans ; Reproducibility of Results ; Rodentia

Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse event related to administration of antiresorptive or antiangiogenic medications. With the increasing usage of bone-modifying agents in cancer therapy, the incidence of MRONJ enhanced gradually, which affects the life quality of patients and interferes with cancer therapy. In 2019, Multinational Association of Supportive Care in Cancer (MASCC), International Society of Oral Oncology (ISOO) and American Society of Clinical Oncology (ASCO) convened a multidisciplinary Expert Panel to evaluate the evidence and formulate recommendations on practices in the prevention and management of MRONJ in patients with cancer. The present article made an interpretation of Medication-Related Osteonecrosis of the Jaw: MASCC/ISOO/ASCO Clinical Practice Guideline so as to provide clinicians with diagnostic and therapeutic approaches for cancer patients with MRONJ.
Bisphosphonate-Associated Osteonecrosis of the Jaw/therapy* ; Bone Density Conservation Agents/adverse effects* ; Humans ; Jaw ; Medical Oncology ; Neoplasms/drug therapy* ; Osteonecrosis/chemically induced* ; Quality of Life

OBJECTIVE: To summarize the pathological characteristics of medication-related osteonecrosis of the jaw (MRONJ) specimens after jaw curettage or jaw osteotomy treatment and to comprehensively analyze the relationship between the different pathological features, treatment methods, and treatment effects to provide new ideas for effective treatment of MRONJ in clinical work. METHODS: The clinical and pathological data were collected from 23 patients with MRONJ who were treated with curettage (18 patients) and jaw osteotomy (5 patients) at the Department of Oral and Maxillofacial Surgery of Peking University Hospital of Stomatology between June 2014 and December 2015. The pathological characteristics of MRONJ were summarized and analyzed with treatment effects based on various surgical treatment methods. The diagnostic criteria and disease staging of MRONJ were determined according to the 2014 American Association of Oral and Maxillofacial Surgeon's Position Paper. RESULTS: In this study, 5 patients have treated with jaw segmental osteotomy, and all of them were in stage Ⅲ; the other 18 patients were treated with jaw curettage, including 5 patients in stage Ⅱ and 13 patients in stage Ⅲ. The pathological features of MRONJ in five cases of jaw segmental osteotomy were divided into three adjacent regions from shallow to deep: inflammation region (IR), sclerosis region (SR), and bone remodeling layer (BRL). Moreover, three types of pathological features of specimens from traditional curettage were defined as type 1 (IR), type 2 (IR + SR), and type 3 (IR + SR + BRL). The pathological features of the patients treated with jaw curettage were: type Ⅰ, 38.9% (7/18); type Ⅱ, 44.4% (8/18); type Ⅲ, 16.7% (3/18). Complete healing was achieved in 5 patients treated with jaw segmental osteo-tomy. Moreover, 2 cases with type Ⅰ, 1 case with type Ⅱ, and 1 with type Ⅲ completely healed after jaw curettage, while 5 cases with type Ⅰ, 7 cases with type Ⅱ, and 2 cases with type Ⅲ experienced recurrence after surgery. CONCLUSION Pathological features of continuous regions of inflammation, sclerosis, and bone remodeling layer were identified from shallow to deep, based on the microscopic observation of jaw segmental osteotomy samples. Insufficient removal of the sclerotic region during jaw curettage that blocks the required blood, nutritional factors, and mesenchymal stem cells seems to be a common cause for failed treatment of MRONJ after curettage surgery.
Humans ; Bisphosphonate-Associated Osteonecrosis of the Jaw/etiology* ; Sclerosis/complications* ; Wound Healing ; Treatment Outcome ; Inflammation/complications* ; Bone Density Conservation Agents/adverse effects* ; Diphosphonates/adverse effects*

The morbidity rate of medication-related osteonecrosis of the jaws (MRONJ) increased rapidly in recent years. Thusfar, the mechanism of MRONJ has no consensus. The possible mechanisms may include bone remodeling inhibition theory, angiogenesis inhibition theory, oral microorganism infection theory, immunosuppression theory, cytotoxicity-targeted oral epithelial cells, microcrack formation of maxillary or mandibular bone, and single nucleotide polymorphism. However, the efficacy of prevention and treatment based on a single mechanism is not ideal. Routine oral examination before MRONJ-related drug treatment, treatment of related dental diseases, and regular oral follow-up during drug treatment are of great significance for the prevention of MRONJ. During the treatment of MRONJ, the stage of MRONJ must be determined accurately, treatment must be standardized in accordance with the guidelines, and personalized adjustments must be made considering the specific conditions of patients. This review aimed to combine the latest research and guidelines for MRONJ and the experiences on the treatment of MRONJ in the Maxillofacial Surgery Department of West China Hospital of Stomatology, Sichuan University, and discuss the strategies to improve the clinical process.
Bisphosphonate-Associated Osteonecrosis of the Jaw/prevention & control* ; Bone Density Conservation Agents ; Bone Remodeling ; China ; Humans ; Jaw