# Bone Changes in Mandibular Condyle of Temporomandibular Dysfunction Patients Recognized on Magnetic Resonance Imaging

## TL;DR

This study identifies different types of bone changes in the jaw joints of patients with temporomandibular dysfunction using MRI and links them to symptoms and gender differences.

## Contribution

The study provides new insights into the relationship between specific bone changes and clinical features in temporomandibular disorder patients.

## Key findings

- Bone changes were found in 30.8% of subjects, including erosion, flattening, osteophyte, and atrophy.
- TMJ pain, opening dysfunction, and joint effusion varied significantly among bone change types.
- Gender differences and disc displacement patterns were associated with specific bone changes.

## Abstract

We aimed to investigate the type of bone changes in temporomandibular disorder patients with disc displacement. The subjects were 117 temporomandibular joints that were diagnosed with anterior disc displacement using magnetic resonance imaging (MRI). Temporomandibular joint (TMJ) pain and opening dysfunction were examined. Disc displacement with and without reduction, joint effusion, and bone changes in the mandibular condyle were assessed on MRI. The types of bone changes were classified into erosion, flattening, osteophyte, and atrophy on the MR images. Fisher’s exact test and χ2 test were performed for analyses. Bone changes were found on 30.8% of subjects with erosion, flattening, osteophyte, and atrophy types (p < 0.001). The occurrence of joint effusion appearance (p < 0.001), TMJ pain (p = 0.027), and opening dysfunction (p = 0.002) differed among the types of bone changes. Gender differences were also found among the types of bone changes (p < 0.001). The rate of disc displacement with reduction was significantly smaller than that of disc displacement without reduction on flattening and osteophyte (p < 0.001). The results made it clear that the symptoms, gender, and presence or absence of disc reduction differed among the types of bone changes.