Background: Masseter muscle pathologies include hypertrophy and the experience of pain, which clinically manifest with increased stiffness and tension. Assessment of muscle stiffness has been gaining importance among physicians dealing with temporomandibular disorders (TMD). Currently, shear wave elastography (SWE) is still often performed by radiologists, while dentists diagnose, treat and monitor TMD.
Objectives: In this cohort study, we investigated whether dentists trained to use SWE can obtain reliable measurements of masseter muscle stiffness following participation in a short training program and hands-on workshop.
Material and methods: A group of healthy volunteers was examined by an experienced radiologist and a novice dentist before and after the training.
Results: The mean values of stiffness obtained by the operators were consistent and ranged from 10.20 kPa to 10.84 kPa. Intraobserver agreement was excellent for measurements of the radiologist (intraclass correlation coefficient (ICC) 0.92 and 0.93, respectively). The training improved the agreement between measurements made by the dentist from poor before the training (ICC = 0.46) to good after the training (ICC = 0.89). Also, the operator agreement between the radiologist and dentist increased from poor (ICC = 0.48) before the training to good (ICC = 0.84) after the training.
Conclusions: The diagnostic accuracy of measuring masseter muscle stiffness was acceptable among dentists after the training. For this reason, the patient can be diagnosed by a single TMD specialist. This can shorten the diagnostic process and reduce treatment costs.
Keywords: elasticity; interobserver agreement; intraobserver agreement; shear wave elastography; temporomandibular disorders.