(38) Should Mandibular Tori be Documented in the Literature as a Known Risk Factor for Medication-related Osteonecrosis of the Jaw?

Abstract: Medication-related osteonecrosis of the jaw (MRONJ) is a rare, yet severe disease induced by antiresorptive medications and antiangiogenic medications. In the 2022 AAOMS Position Paper on MRONJ, several notable local risk factors were described, including inciting dental trauma, the wearing of dentures, and concomitant oral diseases such as periodontitis and periapical pathologies [1]. One potential risk factor that was not defined in this position update, however, is the presence of mandibular lingual tori. While the exact mechanism is unclear, some hypothesize that, due to the thin mucosal layer surrounding the lingual tori, the underlying bone can be more easily damaged, thereby triggering the pathological cascade of ONJ [2]. Although the relationship between mandibular lingual tori and MRONJ development has not yet been clearly described, the data presented in this study suggests that mandibular tori should be included in the list of risk factors.

A retrospective descriptive study was designed using the operating room surgical records of a single surgeon at both the University of Texas Southwestern Medical Center and Parkland Memorial Hospital. The cases analyzed occurred between July 2016 to January 2023 and involved surgical therapy for MRONJ. The procedures analyzed were either coded as a “mandibulectomy”, “maxillectomy”, “mandibular resection”, and/or “neoplasm of maxilla or mandible”. The following inclusion criteria were defined: 1) patients with diagnosed MRONJ on the pathology report; and 2) patients brought to the operating room for surgical treatment of their pathology. Data collection included demographics, the location of the pathology, the medication that induced the MRONJ, and the stage of MRONJ. For the location of pathology, the jaws were divided up into sextants (anterior versus posterior MRONJ) with the mandibular tori being an isolated location.

A total of 42 patients met the inclusion criteria. The average age was 69.81 with females making up most of the patients (n=32). 59.5% of patients were white (n=25), and there was a total of 59 sites of MRONJ in the entire population. Of the 44 mandibular sites, there was a total incidence of 15.91% for mandibular tori (n=7) [Figure 1]. Most sites had stage 2 MRONJ (n=29); furthermore, 100% of sites located on mandibular tori had stage 2 MRONJ (n=7). Regarding medication, Zometa was the primary cause of morbidity in the entire population (n=31).

Mandibular tori play a large part in the development of MRONJ cases that are taken to the operating room. Healthcare providers need to diagnose these tori before antiresorptive therapy. The authors suggest close monitoring of these tori and possibly surgical removal before beginning the antiresorptive therapy in hopes of avoiding this serious complication. Future studies can explore the success rates of treating mandibular tori MRONJ with invasive versus noninvasive approaches.

Mandibular sites of MRONJ