Shear Wave Elastography in Bruxism—Not Yet Ready for Clinical Routine

Abstract

Ultrasound shear wave elastography (SWE) is an emerging modality for the estimation of stiffness, but it has not been studied in relation to common disorders with altered stiffness, such as bruxism, which affects almost one-third of adults. Because this condition could lead to an increased stiffness of masticatory muscles, we investigated SWE in bruxism according to a proof-of-principle and feasibility study with 10 patients with known bruxism and an age- and gender-matched control group. SWE of the left and right masseter muscles was estimated under three conditions: relaxed jaw, 50% of the subjective maximal bite force, and maximal jaw opening. Rejecting the null hypothesis, SWE was significantly increased during relaxed jaw (bruxism 1.92 m/s ± 0.44; controls 1.66 m/s ± 0.24), whereas for maximal mouth opening, the result was vice versa increased with 2.89 m/s ± 0.93 for bruxism patients compared with 3.53 m/s ± 0.95 in the healthy control, which could be due to limited jaw movement in chronic bruxism patients (bruxism 4.46 m/s ± 1.17; controls 5.23 m/s ± 0.43). We show that SWE in bruxism is feasible and could be of potential use for diagnostics and monitoring, though we also highlight important limitations and necessary methodological considerations for future studies.

Dynamic Quantitative Imaging of the Masseter Muscles in Bruxism Patients with Myofascial Pain: Could It Be an Objective Biomarker?

“…Jafari et al [15] reported greater MM thickness in bruxers. However, Tetsuka et al [16] and Toker et al [17] measured thinner, narrower, and shorter MMs in the relaxed jaw.…”

“…Quantifying the size of MM has limited value because of the difficulty of defining normalized dimensions due to the many variables that affect muscle size, such as age, gender, body mass index, and certain medical problems. However, studies have shown that there is a noticeable difference in muscle size, especially during relaxation, in bruxism patients compared to normal individuals, although a cut-off value could not be determined [15,17]. Jafari et al [15] reported greater MM thickness in bruxers.…”

“…SWE is a promising new imaging technique using ultrasound waves to measure the stiffness of tissues. It seems to have the potential to be an objective biomarker that can quantify masticatory muscle stiffness with high reproducibility, low operator dependency, strong reliability, and easy applicability [17][18][19].…”

An Algorithm for Jaw Pain among Divers

“…Future research endeavours in the realm of jaw pain among divers are underway. With the advent of new tools such as advanced three-dimensional (3D) US or US shear wave elastography (SWE) [ 44 ], conducting projects in this field will become more feasible and may uncover new insights. Another intriguing prospect is the utilization of artificial intelligence (AI), which is still in its nascent stages.…”

A Case-Control Study of 40 Patients with Piriformis Muscle Syndrome to Evaluate Diagnostic Findings Using Two-Dimensional Ultrasound and Shear Wave Elastography

“…Ultrasonic SWE is a new imaging method that has been applied to the quantitative assessment of tissue elasticity [ 20 , 31 – 33 ]. SWE technology has been used to assess the elasticity of the upper trapezius muscle and its influencing factors [ 21 ], in joint laxity [ 20 ], identifying plantar fasciitis [ 22 ], in the screening of polymyositis (PM) and dermatomyositis (DM) [ 23 ], and assessment of the difference between benign and malignant thickening of the gallbladder wall [ 24 ].…”