Naslov
Silent period of mandibular elevator muscles in individuals with normal occlusion regulated by periodontal receptors

Autori
Celebic, Asja ; Valentic Peruzovic, Melita ; Vojvodic, Denis ; Cifrek, Mario ; Magjarevic, Ratko ; Kern, Josipa.

Izvornik
Periodicum biologorum (0031-5362) 98 (1996), 1; 55-59

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Silent period ; Natural teeth ; Temporalis and masseter muscle ; OCC cycle ; EMG

Sažetak
Background and Purpose: There have been some questions raised in the literature on the normal values of silent period (SP) latency and duration. The aims of the present study were: 1. to establish normal values for the latency and duration of an SP elicited in an open-close-clench cycle (OCC) in individuals having all the teeth and normal occlusion and 2, to compare the latency and duration of an SP between the different elevator muscles examined. Material and Methods: Silent periods (SP) were registered and measured in 62 individuals with normal occlusion on a new EMGA-1 apparatus, The EMGA-1 apparatus consists of an 8-channel amplifier (6 channels for mioelectrical signal registration and 2 channels for audio-signal registration) and a personal AT computer with "Medwin" software for registration of EMG and audio signals, recording and analysis. Registered signals can be magnified and/or superimposed and the measurements are performed directly on the screen by cursors, which means that the analysis is very precise. Ten registrations of an open-close-clench (OCC) cycle was made for each participant. Signals from the right and left anterior temporal and masseter muscles were recorded by surface electromyography during 240-300 msec for each OCC cycle. Results: Silent periods emerged on the EMG trace with a latency of 12.S-12.9 msec after the occlusal contact (audio trace) and had only a single short inhibitory pause and the inhibition of motoneurons was complete. The duration of the SP was 20.1-21.1 msec. There were no statistically significant differences for the latency (p gt 0.05) and the duration (p gt 0.05) of the SP between the examined muscles. The reflex was considered as oligosynaptic one. Stimulation of the primary afferents of penodontal ligament by tensile forces along the long axes of the root of the tooth was caused by the pressure forces generated in OCC cycles between the occlusal surfaces of the opposing teeth, perpendicular to the occlusal surface, as the occlusion was normal, without any interferences. Conclusion: The data for the SP latency and duration registered and analyzed according to standardised procedure on the precise EMGA-1 apparatus can serve as referent values for the individuals with healthy occlusion.

Izvorni jezik
Engleski

Znanstvena područja
Dentalna medicina, Interdisciplinarne biotehničke znanosti

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