# Uncovering jaw-specific radiographic differences in medication related osteonecrosis of the jaws (MRONJ): a case-control study

## TL;DR

This study identifies distinct radiographic patterns in maxillary and mandibular MRONJ, which can help diagnose the condition earlier and improve treatment.

## Contribution

The study introduces a matched case–control design to uncover jaw-specific radiographic signatures of MRONJ.

## Key findings

- Osteolysis is significantly more common in maxillary MRONJ compared to mandibular cases.
- Mandibular MRONJ shows higher frequencies of periosteal reaction and sequestration.
- Recognizing these jaw-specific imaging features can improve diagnostic accuracy and promote earlier intervention.

## Abstract

To compare the radiographic manifestations of medication-related osteonecrosis of the jaw (MRONJ) between the maxilla and the mandible using a matched case–control design, and to identify jaw-specific imaging features that may support early diagnosis.

A retrospective analysis was conducted on 109 MRONJ patients treated between 2013 and 2024 at a tertiary care center. A matched cohort of 45 patients (15 maxillary, 30 mandibular) was created based on age (± 2 years), gender, and underlying condition (osteoporosis vs. malignancy). Demographic, clinical, and radiographic data using cone-beam computed tomography (CBCT) or multidetector computed tomography (MDCT), were extracted and analyzed. Radiographic features evaluated included osteolysis, sclerosis, periosteal bone formation, and sequestration.

Demographic and clinical variables were similar between the groups. Radiographically, osteolysis was significantly more common in maxillary MRONJ (93.3% vs. 63%, P = 0.0319), while the mandible showed higher frequencies of periosteal reaction (50% vs. 6.6%, P = 0.0042) and sequestration (80% vs. 33.3%, p = 0.0021). Sclerosis was more common in mandibular cases (90% vs. 73.3%) but did not reach statistical significance (P = 0.1458). No significant differences were observed in MRONJ staging or comorbidities (P > 0.05 respectively).

Maxillary and mandibular MRONJ demonstrate distinct radiographic patterns, likely reflecting anatomical and vascular differences. The predominance of osteolysis in the maxilla, which often presents with less specific symptoms, may contribute to delayed diagnosis. Recognizing these jaw-specific imaging features can improve diagnostic accuracy and promote earlier intervention, particularly for maxillary MRONJ.

By uniquely applying a matched case–control design, this study uncovers a jaw-specific radiographic signatures of MRONJ—highlighting the overlooked dominance of osteolysis in the maxilla and the aggressive periosteal and sequestration changes in the mandible—offering a powerful diagnostic lens for earlier, site-specific intervention.