Madonna Rofaeel1, Jeffrey Chi-Fai Chow1, Iacopo Cioffi2. 1. Centre for Multimodal Sensorimotor and Pain Research, Faculty of Dentistry, University of Toronto, 123 Edward St, Room 501, Toronto, ON, M5G 1E2, Canada. 2. Centre for Multimodal Sensorimotor and Pain Research, Faculty of Dentistry, University of Toronto, 123 Edward St, Room 501, Toronto, ON, M5G 1E2, Canada. iacopo.cioffi@dentistry.utoronto.ca.
Abstract
OBJECTIVES: Trait anxiety is associated with an increased occurrence of awake bruxism episodes, a behavior characterized by clenching of the teeth contributing to temporomandibular disorders in some individuals. Here we measured the activity of the masseter and the intensity and duration of spontaneous wake-time tooth clenching episodes in healthy individuals with different levels of trait anxiety (TA). MATERIALS AND METHODS: Two hundred fifty-five individuals completed a web survey. Using their TA scores, we allocated them in low (< 20th percentile of the TA score distribution), intermediate (between 20th and 80th ), and high (> 80th) TA groups. We analyzed the electromyographic (EMG) activity of the right masseter during a 15-min silent reading task in forty-three individuals with low (n = 12), intermediate (n = 17), and high TA (n = 14). We tested between-group differences in EMG activity of the masseter, as well as postural activity-the muscular activity that maintains mandibular posture, and amplitude and duration of spontaneous tooth clenching episodes. RESULTS: The activity of the masseter (mean ± SEM %maximum voluntary contraction/MVC) was greater in the high TA (10.23 ± 0.16%MVC) than the intermediate (8.49 ± 0.16%MVC) and low (7.97 ± 0.22%MVC) TA groups (all p < 0.001). Postural activity did not differ between groups (all p > 0.05). The EMG amplitude of tooth clenching episodes was greater in the high TA (19.97 ± 0.21 %MVC) than the intermediate (16.40 ± 0.24%MVC) and low (15.48 ± 0.38 %MVC) TA groups (all p < 0.05). The cumulative duration of clenching episodes was not different between groups (p = 0.390). CONCLUSIONS: Increased TA is associated with both increased masseter muscle activity and intensity of wake-time tooth clenching episodes. CLINICAL RELEVANCE: TA may contribute significantly to masticatory muscle overload.
OBJECTIVES: Trait anxiety is associated with an increased occurrence of awake bruxism episodes, a behavior characterized by clenching of the teeth contributing to temporomandibular disorders in some individuals. Here we measured the activity of the masseter and the intensity and duration of spontaneous wake-time tooth clenching episodes in healthy individuals with different levels of trait anxiety (TA). MATERIALS AND METHODS: Two hundred fifty-five individuals completed a web survey. Using their TA scores, we allocated them in low (< 20th percentile of the TA score distribution), intermediate (between 20th and 80th ), and high (> 80th) TA groups. We analyzed the electromyographic (EMG) activity of the right masseter during a 15-min silent reading task in forty-three individuals with low (n = 12), intermediate (n = 17), and high TA (n = 14). We tested between-group differences in EMG activity of the masseter, as well as postural activity-the muscular activity that maintains mandibular posture, and amplitude and duration of spontaneous tooth clenching episodes. RESULTS: The activity of the masseter (mean ± SEM %maximum voluntary contraction/MVC) was greater in the high TA (10.23 ± 0.16%MVC) than the intermediate (8.49 ± 0.16%MVC) and low (7.97 ± 0.22%MVC) TA groups (all p < 0.001). Postural activity did not differ between groups (all p > 0.05). The EMG amplitude of tooth clenching episodes was greater in the high TA (19.97 ± 0.21 %MVC) than the intermediate (16.40 ± 0.24%MVC) and low (15.48 ± 0.38 %MVC) TA groups (all p < 0.05). The cumulative duration of clenching episodes was not different between groups (p = 0.390). CONCLUSIONS: Increased TA is associated with both increased masseter muscle activity and intensity of wake-time tooth clenching episodes. CLINICAL RELEVANCE: TA may contribute significantly to masticatory muscle overload.
Authors: F Lobbezoo; J Ahlberg; K G Raphael; P Wetselaar; A G Glaros; T Kato; V Santiago; E Winocur; A De Laat; R De Leeuw; K Koyano; G J Lavigne; P Svensson; D Manfredini Journal: J Oral Rehabil Date: 2018-06-21 Impact factor: 3.837