Kurtosis, a new variable with possible diagnostic value in analysis of jaw muscle surface EMG

Abstract

BackgroundThere is a need for methods to compare differences of voltage levels and distribution anomalies in the study of skeletal muscle function. Calculating the kurtosis values has been found to be of value.AimThe aim was to record and analyse voltage and kurtosis levels of SEMG recorded bilaterally in the masseter and anterior temporalis areas during rest and clenching and to compare the kurtosis levels between controls and patients with TMJ disc dysfunction.Material and methodsTwenty‐three healthy subjects and 21 patients with TMJ disc dysfunction were taken part in this study. Recordings were made with the BioPAK EMG System. Gain was adjusted to record the data within the range of ±2000 µV. SEMG was recorded in four facial areas, the right masseter, left masseter, right anterior temporalis, and left anterior temporalis areas. Kurtosis levels of SEMG, at clenching with maximal force, and mandibular rest, were compared between the control and patient groups.ResultsThe kurtosis levels of clenches were significantly higher in patients in all four areas with sensitivity, 38.1% to 61.9%, and specificity, 82.6% to 100.0%. No differences were found in kurtosis levels during mandibular rest.ConclusionThe results support that kurtosis values of SEMG recorded during clenching have a potential diagnostic interest.This article studied voltage levels and distribution anomalies with kurtosis values in control and TMJ disc dysfunction subjects. Kurtosis values are higher in patients with disc dysfunction than in healthy subjects and may be as a potential diagnostic value to evaluate mastication muscle function.