18 Years of Medication-Related Osteonecrosis of the Jaw (MRONJ) Research: Where Are We Now?—An Umbrella Review

Background: Osteonecrosis of the jaw (ONJ) is a condition affecting patients exposed to medications used to treat benign and malignant conditions of bone tissue. Many studies have highlighted that ONJ is a severe condition, which is very challenging to manage, especially in individuals with oncologic disease. The aim of this umbrella review is to analyze all available interventional and non-interventional systematic reviews published on medication-related osteonecrosis of the jaw (MRONJ) and summarize this evidence. Material and methods: A multi-database search (PubMed, MEDLINE, EMBASE and CINAHL) was performed to identify related multi-language papers published from January 2003 until June 2021. An additional manual search was also performed in systematic review registries (PROSPERO, INPLASY, JBI and OFS) to identify possible missing reviews. Data were extracted from relevant papers and analyzed according to the outcomes selected in this review. Results: The search generated 25 systematic reviews eligible for the analysis. The total number of patients included in the analysis was 80,840. Of the reviews, 64% (n = 16) were non-interventional and 36% (n = 9) were interventional. Study designs included case series 20.50% (n = 140), retrospective cohort studies 12.30% (n = 84) and case reports 12.20% (n = 83). It was unclear what study design was used for 277 studies included in the 25 systematic reviews. Conclusions: The data reviewed confirmed that the knowledge underpinning MRONJ in the last 20 years is still based on weak evidence. This umbrella review highlighted a widespread low-level quality of studies and many poorly designed reviews.