Comparative ultrasonographic evaluation of the masseter muscle in patients with and without oral submucous fibrosis

Background: The gold standard for diagnosing oral submucous fibrosis (OSF) is histopathology, but it causes scarring and worsens the illness. Ultrasonography (USG) has been employed in recent research to assess the cross-sectional dimensions of head and neck muscles in OSF patients. Aim: This study aimed to evaluate the ultrasonographic changes in the cross-sectional thickness of masseteric muscle in patients with and without OSF. Also, to compare the cross-sectional thickness of masseteric muscle in patients with different clinical stages and histologic grades of OSF. Methods: The study was conducted in accordance with the Declaration of Helsinki. The protocol was approved by the Institutional Ethics Committee, and written informed consent was obtained from all patients. The study population was divided into cases and controls. Cases consisted of 63 patients clinically diagnosed as having OSF and controls consisted of 63 persons selected from the patients attending the department of Oral Medicine and Radiology. According to Khanna and Andrade's criteria, OSF patients were divided into four groups based on their clinical findings. Ultrasonography of masseter muscle was performed with a high-resolution real-time LOGIQUE C5 ultrasound scanner with 7–12 MHz transducers. Results: One-way ANOVA and t test were used to evaluate the results. The study showed a clear association of masseter muscle hypertrophy with OSF. In controls, ultrasound measurements of masseter muscle thickness were statistically significant. In the case group, masseter muscle thickness was increased as the duration and frequency of the chewing increased and also as the disease progressed. Conclusions: USG is a valuable, radiation-free, and noninvasive better diagnostic tool than clinical and histopathological examinations for OSF evaluation.