The evaluation of lateral pterygoid signal intensity changes related to temporomandibular joint anterior disc displacement


Cabuk D. S. , ETÖZ M. , AKGÜN İ. E. , DOĞAN S. , Ozturk E., COŞGUNARSLAN A.

ORAL RADIOLOGY, 2020 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume:
  • Publication Date: 2020
  • Doi Number: 10.1007/s11282-020-00427-0
  • Title of Journal : ORAL RADIOLOGY

Abstract

Objectives The aim of this study was to evaluate lateral pterygoid muscle (LPM) signal intensity changes related to different degrees of disc status groups using magnetic resonance imaging (MRI). Methods Four groups were established according to disc displacement of examined temporomandibular joint (TMJ) and opposing TMJ. MRI scans were obtained with a 1.5 T device. The signal intensity was measured from the sagittal slice where midportion of the muscle belly was observed. The regions of interest were placed over the superior and inferior heads of LPM. To normalize differences in signal intensity, signal intensity of the grey matter and white matter of the brain was also measured. Signal intensity ratio (SIR) was calculated. Measurements were performed in both T1- and T2-weighted images. Results In the intergroup comparisons, a statistically significant difference was found for SIR1 sup., SIR1 inf., SIR2 sup. and SIR2 inf. variables (p < 0.01). According to multiple comparison test (Tukey), no significant difference was found between group 0 and group 1 for SIR1 sup., SIR1 inf., SIR2 sup. and SIR2 inf. variables (p > 0.05). For SIR1 sup., SIR1 inf., SIR2 sup. and SIR2 inf. variables, significant differences were found between five binary comparison groups (1-2, 1-3, 2-3, 0-2, 0-3) (p < 0.05). Conclusion In conclusion, SIR is correlated with the degree of disc displacement. The internal derangement of the opposite joint did not affect SIR of superior and inferior heads of examined LPM in both T1- and T2-weighted images. The inferior head of LPM was also found affected by disc displacement.