a 74-year - old woman had a complaint of bony exposure on the left posterior maxilla after spontaneous loss of the left maxillary first and second molars 3 months ago . she had been taking oral risedronate ( actonel ) , a kind of bisphosphonates , 35 mg once weekly for 4 years because of osteoporosis . the intraoral examination revealed the bony exposure on the left maxillary alveolar region , pus discharge , and bleeding on the same site as well as sequestrum detached from the area ( fig . 1 ) . the patient took a panoramic radiograph and ct . on the panoramic radiograph , a large osseous crater and cortical bone destruction were found on the left maxillary edentulous area ( fig . 2 ) . ct images demonstrated cortical bone destruction on the left maxillary edentulous area and maxillary sinus wall . the lesion extended to the maxillary sinus floor and mucositis were observed on the sinus floor . treatment began with the cessation of bisphosphonates therapy and removal of the left maxillary first premolar . 5 ) . through the histopathologic feature , this case was confirmed as bronj . during 6 months 6 ) . a 72-year - old woman had a chief complaint of swelling on the left maxillary canine area after extraction of the left maxillary canine 2 months ago . she had been taking oral risedronate ( actonel ) , a kind of bisphosphonates , 35 mg once weekly for 3 years and 5 months because of osteoporosis . the intraoral examination showed a necrotic bone exposure on the left maxillary edentulous area with a swelling and pus discharge through a fistula . plain radiological examination showed a sequestrum of bony fragment with trabeculation at the socket area ( fig . ct images demonstrated the separated lamina dura from the extraction socket of the canine and mild mucositis on the left maxillary sinus ( fig . the chief complaint was bony exposure on the right mandibular edentulous area with pus discharge ( fig . plain radiographic examination showed the decrease in bone density on the right mandibular alveolar process , resorptive area with irregular shape , and sequestrum on the crestal area ( fig . biopsy from the bony lesion demonstrated sequestrum infiltrated with chronic inflammatory cell as well as bacterial flora ( fig . a 74-year - old woman had a complaint of bony exposure on the left posterior maxilla after spontaneous loss of the left maxillary first and second molars 3 months ago . she had been taking oral risedronate ( actonel ) , a kind of bisphosphonates , 35 mg once weekly for 4 years because of osteoporosis . the intraoral examination revealed the bony exposure on the left maxillary alveolar region , pus discharge , and bleeding on the same site as well as sequestrum detached from the area ( fig . 1 ) . the patient took a panoramic radiograph and ct . on the panoramic radiograph , a large osseous crater and cortical bone destruction were found on the left maxillary edentulous area ( fig . 2 ) . ct images demonstrated cortical bone destruction on the left maxillary edentulous area and maxillary sinus wall . the lesion extended to the maxillary sinus floor and mucositis were observed on the sinus floor . treatment began with the cessation of bisphosphonates therapy and removal of the left maxillary first premolar . 5 ) . through the histopathologic feature , this case was confirmed as bronj . during 6 months a 72-year - old woman had a chief complaint of swelling on the left maxillary canine area after extraction of the left maxillary canine 2 months ago . she had been taking oral risedronate ( actonel ) , a kind of bisphosphonates , 35 mg once weekly for 3 years and 5 months because of osteoporosis . the intraoral examination showed a necrotic bone exposure on the left maxillary edentulous area with a swelling and pus discharge through a fistula . plain radiological examination showed a sequestrum of bony fragment with trabeculation at the socket area ( fig . ct images demonstrated the separated lamina dura from the extraction socket of the canine and mild mucositis on the left maxillary sinus ( fig . the chief complaint was bony exposure on the right mandibular edentulous area with pus discharge ( fig . plain radiographic examination showed the decrease in bone density on the right mandibular alveolar process , resorptive area with irregular shape , and sequestrum on the crestal area ( fig . biopsy from the bony lesion demonstrated sequestrum infiltrated with chronic inflammatory cell as well as bacterial flora ( fig . cells treated with bisphosphonates demonstrate decreased proliferation , increased rate of apoptosis , and a decrease in capillary - tube formation.1,4 bisphosphonates also demonstrate antiangiogenic properties owing to their ability to significantly decrease circulating levels of vascular endothelial growth factor ( vegf).1,8 bronj was first reported in 2003 , recognized a few years after bisphosphonates approval for use.9 there was a growing number of bronj in patients receiving oral bisphosphonates therapy . ortega et al reported that the incidence of bronj varied from 0.15% to 12% of patients receiving bisphosphonates for treatment of osteoporosis.10 there is an increasing concern that oral bisphosphonates are implicated in osteonecrosis of the jaws , albeit less commonly than that observed with the more potent intravenously administered bisphosphonates . recent retrospective clinical studies have identified several potential risk factors associated with the development of bronj . these include a history of dento - alveolar trauma , duration of bisphosphonates exposure , and the type of bisphosphonates.3,7,9 - 12 in the majority of bronj cases reported to date , recent dentoalveolar trauma was the most prevalent and consistent risk factor.3 the lesion related with bronj is most frequently symptomatic when surrounding tissues become inflamed or there is a clinical evidence of infection . signs and symptoms include pain , tooth mobility , mucosal swelling , erythema , and ulceration.2 - 8 some patients may also present with complaints of altered sensation in the affected area.2 these cases showed the clinical features such as pain , bone exposure , pus discharge , bleeding , and swelling . the patients had been taking oral risedronate ( actonel ) , a kind of bisphosphonates 35 mg , once weekly for treatment of osteoporosis for 4 years and 3 years 5 months , respectively . in both cases , there were loss of teeth that could be regarded as the causative factor of dento - alveolar trauma and subsequent osteonecrosis of the jaws . . therefore , panoramic and periapical radiographs may not reveal significant changes in the early stages of osteonecrosis.1 - 3 early or late radiographic changes may mimic classic periapical pathology or osteomyelitis . in the cases presented , plain radiographs and ct images were taken , which showed signs of bone destruction with sequestrum and mucositis on the adjacent maxillary sinus . magopoulos et al3 reported that cessation of bisphosphonates therapy combined with surgical debriment and long term antibiotic therapy was the treatment of choice in bronj patients . in case 1 , the patient was treated with saucerization , decortications , and sequestrectomy on the problematic area with the cessation of bisphosphonates therapy . during the follow - up period of 6 months the patient was treated with saucerization , fistulorraphy , and sequestrectomy without cessation of medication . however , there was recurrence of osteonecrosis on the mandible after 1 year 6 months . saucerization , decortications , and sequestrectomy were performed with the cessation of bisphosphonates therapy . during the follow - up period of 3 months it is critical that the dentist should be aware of this significant complication which can occur spontaneously or after any dento - alveolar procedure in the population receiving bisphosphonates . because the oral examination and review of the patient 's medical history are currently the most effective and sensitive means of detecting bronj , dental professionals are in a unique position to identify and diagnose this disease process early in its course . this report serves to alert dentists about the potential complication of bone necrosis in patients receiving bisphosphonates therapy . for the treatment of bronj , dentists need to consider ceasing the use of bisphosphonates .
bisphosphonates are compounds used to treat osteoporosis and malignant bone metastasis . despite the benefits related to the use of these medications , osteonecrosis of the jaws 
 is a significant complication in a subset of patients receiving these drugs . 
 this complication occurs either spontaneously or after a simple dento - alveolar surgery . 
 recently there were two patients who showed the features of bisphosphonate related osteonecrosis of the jaws ( bronj ) in gangneung - wonju national university dental hospital . 
 the patients revealed the clinical and radiological features of classical osteomyelitis . 
 this report presents two cases of bronj which were examined by plain radiography and computed tomography .