Etiologic Role of Bacterial Microorganisms in Medication Related Osteonecrosis of the Jaws: a Systematic Review

Objectives: Medication-related osteonecrosis of the jaw (MRONJ) is the condition of bone exposure which lasts more than 8 weeks. It can be associated with clinical symptoms like pain, erythema, and infections. In addition to the physiologic changes of the hard and soft tissue cells, Some different etiologic factors have been suggested for MRONJ but none of them is certainly accepted as the main etiologic factor. One of these factors is the local infection which can be established by bacterial microorganisms and several articles showed different bacterial strains in MRONJ patients at different MRONJ stages; Due to the importance of this issue, we aimed to systematically review the etiologic roles of bacterial microorganisms in MRONJ conditions.
Methods: An electronic search was done on March 20, 2017, at the databases of Cochrane Library, Google Scholar, PubMed (NCBI) and Scopus. Only the in-vitro studies, clinical trials, and prospective and retrospective case reports were included in this review.
Results: A meta-analysis could not be accomplished due to the lack of quantitative evidence and broad heterogeneity of study types, bacterial strains, treatment options and outcomes of these studies; so, only a qualitative analysis was done and the results were reported for the selected studies.
Conclusions: We concluded that there are several bacterial strains at different stages of MRONJ without any definite causal links between them and ONJ. Also, there are controversies about the treatment options, either to use the antibiotic therapy in association with antimicrobial agents (mouthrinses etc.) besides the standard surgical procedure or not. There need to be more quantitative results reported in future studies in order to achieve more certain notions about the etiologic role of bacterial microorganisms in MRONJ patients.