## 3 Discussion  
BPs bind to the hydroxyapatite and deposit in the bone. During the bone remodeling cycle, the BPs are released from the hydroxyapatite and inhibit osteoclast-mediated bone resorption [14]. Two theories are proposed for MRONJ pathogenesis. In the first theory, the MRONJ originates from the bone through osteoclasts inhibition and then spreads to the soft tissue (inside-outside). The other less likely theory, MRONJ develops primarily from soft tissue necrosis and then spreads to the bone [15].  
In a cohort study, [PERSON] et al. found the ONJ prevalence was 0.10% among the patients receiving chronic oral BPs. The prevalence was higher among patients receiving oral BPs after 4 years or more (0.21%) compared with those with 4 years of exposure (0.21% vs. 0.04%, respectively) [6]. Another study conducted by [PERSON] et al. reported that the incidence of ONJ increased from 1.5% among patients receiving BP for 4 to 12 months to 7.7% for those who were treated for 37 to 48 months [16].  
The pathogenesis of MRONJ is multifactorial, however, the presence of a local factor plays an important role in the initiation of osteonecrosis [17]. In a study by [PERSON] and [PERSON], the two main factors associated with MRONJ were dental extraction and dental prosthesis [18]. In another case-controlled study, the risk factors for ONJ development were evaluated in 20 breast cancer patients receiving BP. They found that 8 of the ONJ cases (40%) were wearing dentures (\(p\) = 0.064) [12]. In a prospective study by [PERSON] et al., 2 of 17 patients diagnosed with ONJ in the mandible were wearing dentures, and in both cases, ONJ developed with multiple myeloma after receiving BPs [16].  
In this case report, the radiographs were used to confirm the diagnosis and evaluate the extent of the lesion besides the clinical examination. Thus, several authors have emphasized the importance of the radiographic features of MORNJ and suggested that the radiographical findings should be added to the AAOMS's staging [3; 19; 20].  
During the comprehensive oral examination, the treating dentist or prosthodontist should be able to identify all possible risk factors for MORNJ such as bony spikes, spicules, and exostoses, and pre-prosthetic surgeries that may be recommended for some patients if needed [21]. For denture fabrication, extra attention should be paid to denture relief areas, proper denture base extension, and impression techniques, and occlusion to minimize the trauma to underlying tissue during mastication [21]. Additionally, efforts should be made by both the dentist and patient regarding the development of good oral hygiene protocol.  
To reduce the risk of MRONJ, all patients must be educated about the risk of MRONJ and the importance of maintaining good oral hygiene. They also must be carefully examined prior to the administration of antiresorptive therapy. Comprehensive dental treatment should be performed to reduce the need for dental procedures during the treatment. Moreover, all invasive dental treatments such as extraction of non-restorable teeth and necessary periodontal surgeries should be performed. Also, the existing dentures should be carefully examined, and poorly fitting dentures must be adjusted or replaced to reduce tissue trauma. For patients who already have started the treatment, invasive dentoalveolar surgical procedures should be avoided as much as possible to reduce the risk of MRONJ. Therefore, endodontic treatment is preferable for non-restorable teeth instead of extraction [3; 22].