OWN - Quintessenz Verlags-GmbH CI - Copyright Quintessenz Verlags-GmbH OCI - Copyright Quintessenz Verlags-GmbH TA - J CranioMand Func JT - Journal of Craniomandibular Function IS - 1868-4149 (Print) IP - 1 VI - 14 PST - ppublish DP - 2022 PG - 25-34 LA - en TI - Correlation between sleep-time masseter muscle activity and tooth wear FAU - Manfredini, Daniele AU - Manfredini D FAU - Lombardo, Luca AU - Lombardo L FAU - Visentin, Alessandra AU - Visentin A FAU - Arreghini, Angela AU - Arreghini A FAU - Siciliani, Giuseppe AU - Siciliani G CN - OT - electromyography OT - masticatory muscles activity OT - sleep bruxism OT - tooth wear AB - Aims: To assess the correlation between tooth wear and sleep-time masseter muscle activity (sMMA) in a group of healthy young adults who underwent home electromyographic/electrocardiographic (EMG/ECG) recordings with a portable device. Methods: A total of 41 healthy volunteers (23 women, 18 men; mean age 28.8 years, range 25 to 40) with good natural dentition underwent a 2-night in-home evaluation with a portable device that allowed a simultaneous sleep-time recording of EMG signals from both masseter muscles and heart rate. The number of sleep bruxism (SB) episodes per sleep hour (SB index); the number of phasic, tonic, and mixed sMMA events per hour; and the total number of sMMA events per night were calculated. All individuals also underwent an assessment of tooth wear on digital casts with the adoption of a six-degree rating scale. Correlations between sMMA variables and tooth wear were assessed using the Pearson test. The null hypothesis was that correlation between the two conditions would not be significant. Results: On average, the SB index was 4.5 ± 2.6, while the total number of sleep-time masseter contractions was 97.2 ± 55.2. Of those contractions, almost 60% were phasic. Average tooth wear was 1.5 ± 0.7, with the canines and mandibular incisors showing the highest wear scores. For all pairwise analyses, correlation values were not significant (P values 0.11 to 0.69), with r values ranging from 0.064 to 0.253. Conclusion: The null hypothesis of an absence of correlation between tooth wear and sMMA could not be rejected, implying that tooth wear cannot be used as an indicator of ongoing SB or sMMA. Future studies taking into account the multifaceted nature of tooth wear and the complex natural course of sleep phenomena are encouraged to investigate the issue further, at the individual level. J Oral Facial Pain Headache 2019;33:199–204. doi: 10.11607/ofph.2081 AID - 2864463