Clinical characteristics and recurrence-related factors of medication-related osteonecrosis of the jaw

OBJECTIVES: The purpose of this study was to investigate the demographic and clinical characteristics of patients with medication-related osteonecrosis of the jaw (MRONJ) and to elucidate factors affecting recurrence in surgical treatment. MATERIALS AND METHODS: A total of 51 patients who were diagnosed with MRONJ were analyzed according to demographic and clinical features and treatment results through a retrospective chart review from 2013 to 2017 in the Department of Oral and Maxillofacial Surgery, Korea University Anam Hospital, Seoul in Korea. RESULTS: Alendronate composed the majority of medication doses (55.6%), followed by ibandronate (20.0%), risedronate (15.6%), and zoledronate (6.7%). Forty patients (88.9%) were given oral medication, and five patients (11.1%) were intravenously treated, and the mean duration of medication use was 61.1±42.9 months. A total of 10 patients (22.2%) had a drug holiday before MRONJ-induced dental treatment lasting an average of 6.8±7.0 months. MRONJ occurred 2.7 times more in the mandible, with 41 cases (73.2%) occurring in the mandible and 15 cases (26.8%) occurring in the maxilla, and the prevalence of affected posterior parts (premolar-molar) was six times greater than that of the anterior parts (incisor-canine) (48 cases vs 8 cases, 85.7% vs 14.3%). The most common dental cause of MRONJ was tooth extraction (69.6%). Regarding recurrence, there was no statistical difference in recurrence rate according to either site or stage. However, recurrence occurred in 4 out of 34 cases (11.8%) in the primary closure group and 9 out of 20 cases (45.0%) in the secondary healing group, and there was a statistical difference with respect to closure technique. CONCLUSION: The identified risk factors in patients taking bone resorption inhibitors can aid dental clinicians in ensuring prevention and proper treatment of MRONJ.

Combined effect of bisphosphonate and recombinant human bone morphogenetic protein 2 on bone healing of rat calvarial defects / 대한악안면성형재건외과학회지

PURPOSE: This study aimed to investigate new bone formation using recombinant human bone morphogenetic protein 2 (rhBMP-2) and locally applied bisphosphonate in rat calvarial defects. METHODS: Thirty-six rats were studied. Two circular 5 mm diameter bony defect were formed in the calvaria using a trephine bur. The bony defect were grafted with Bio-Oss(R) only (group 1, n = 9), Bio-Oss(R) wetted with rhBMP-2 (group 2, n = 9), Bio-Oss(R) wetted with rhBMP-2 and 1 mM alendronate (group 3, n = 9) and Bio-Oss(R) wetted with rhBMP-2 and 10 mM alendronate (group 4, n = 9). In each group, three animals were euthanized at 2, 4 and 8 weeks after surgery, respectively. The specimens were then analyzed by histology, histomorphometry and immunohistochemistry analysis. RESULTS: There were significant decrease of bone formation area (p < 0.05) between group 4 and group 2, 3. Group 3 showed increase of new bone formation compared to group 2. In immunohistochemistry, collagen type I and osteoprotegerin (OPG) didn't show any difference. However, receptor activator of nuclear factor kappaB ligand (RANKL) decreased with time dependent except group 4. CONCLUSION: Low concentration bisphosphonate and rhBMP-2 have synergic effect on bone regeneration and this is result from the decreased activity of RANKL of osteoblast.

Treatment and Prognosis of Femoral Insufficiency Fracture Associated with Prolonged Bisphosphonate Use

PURPOSE: This study was conducted to investigate and identify an appropriate fracture treatment method by analyzing patients in whom a femoral incompetence fracture occurred after receiving a long-term bisphosphonate administration. MATERIALS AND METHODS: The subjects of this study were 13 cases out of ten patients among those who had a history of receiving bisphosphonate for more than five years and had a fracture or an imminent fracture with a characteristic radiological finding in the femoral subtrochanteric region and the interfemoral region. The period of the drug administration, bone density, the existence of a prodromal symptom, and bilateral fracture were investigated. RESULTS: In seven out of the 13 cases, the patients complained of painat the femoral and pelvic parts as a prodrome (53.8%), and three of them showed a bilateral fracture (30%). An imminent fracture with a prodrome was observed in six cases (46.2%); for three of these cases, a prophylactic fixture pexis was performed by inserting a metal nail into the medullary cavity, and in two out of these three, a complete fracture was found within 11 months on average (3 to 19 months). In the three prophylactic fixture pexis performed cases, no postoperative complications were found, and a radiological finding of concrescence was seen within one year after the operation. Among the nine operation performed cases after the fracture, non-union was found in two. CONCLUSION: In the patients who have received bisphosphonate for a long periodof time, a prodome may be a useful indicator of a fracture in the femoral subtrochanteric region and the interfemoral region; therefore, a careful observation is necessary. A prophylactic internal fixation is recommended for patients with imminent fracture with a prodome since they have a high risk of a complete fracture is high in them.

Influence of Insurance Benefit Criteria on the Administration Rate of Osteoporosis Drugs in Postmenopausal Females

BACKGROUND: Preventive measures need to be implemented to lower the incidence of osteoporotic fractures. Osteoporotic fractures increase morbidity and mortality as well as impose a socioeconomic burden; however, current research is limited to the administration rates of osteoporosis drugs for Korean postmenopausal females. METHODS: This study represents a nationwide, observational, and cross-sectional survey that investigates the administration rates of osteoporosis drugs based upon a bone mineral density (BMD) test performed on Korean postmenopausal patients who visited outpatient orthopedic clinics. BMD test results were examined in postmenopausal female patients (50 to 80 years of age); subsequently, the patients were classified into an osteoporosis group, osteopenia group, and normal group. The administration rates of osteoporosis drugs and bisphosphonates were then analyzed. The osteoporosis group was subdivided into a T-score less than -3.0 group and a T-score between -3.0 and -2.5 group that were separately analyzed. RESULTS: Based on the lumbar spine BMD, the rate of administration of osteoporosis drugs in the osteoporosis group was 42.1%, which was significantly higher compared to the osteopenia group or normal group. A significantly low bone mineral density was observed in patients who were administered bisphosphonates. Based on the lumbar spine BMD, the administration rate of osteoporosis drugs in the group with a T-score between -3.0 and -2.5 (34.2%) was significantly lower than the group with a T-score less that -3.0 (46.2%). The bisphosphonate administration rate was also significantly low; however, the administration rate for osteoporosis drugs was significantly lower than that of the osteopenia group. CONCLUSIONS: Only about 40% of Korean postmenopausal female patients with osteoporosis were administered osteoporosis drugs. The administration rate in patients with a T-score between -3.0 and -2.5 was particularly low and active treatment to prevent osteoporotic fractures is required in this group.

Atypical Subtrochanteric Femur Fracture in Patient with Metastatic Breast Cancer Treated with Zoledronic Acid / 한국유방암학회지

Several case series have suggested an association exists between atypical femoral subtrochanteric fractures and long-term use of bisphosphonates. It is thought that prolonged use of bisphosphonates may lead to adynamic, fragile bone. The radiologic features of atypical fractures include diffuse cortical thickening, transverse fracture, and beaking at the lateral subtrochanteric area. Atypical subtrochanteric femur fractures have been reported after use of alendronate, but there have been rare reports of atypical femur fractures occurring after administration of zoledronic acid. A 56-year-old female with metastatic breast cancer treated with zoledronic acid presented with pain in the right hip. X-rays showed a right subtrochanteric fracture, and she underwent operation. Four months later after having undergone an operation, the patient struggled with walking and X-ray showed delayed union of the fracture site.