Occlusal measurement method can affect SEMG activity during occlusion

Abstract

Occlusal indicators are widely used in dental treatment to measure tooth contacts that occur during occlusion. However, the presence of an indicator may affect the mechanics of occlusion and lead to invalid tooth contact data. The objective of this study was to determine the effect of four indicators (Parkell, silk, T-Scan(®) sensor and paper) on surface electromyography (SEMG) activity during occlusion. Twenty-three subjects performed strong bites and maximum clenches onto the four indicators and natural dentition. Surface electromyography recordings of anterior temporalis and superficial masseter activity and the subjects' perception of each indicator were measured. SEMG activity with the T-Scan(®) sensor and paper was significantly different (higher masseter activity; P < 0·05) compared to that for natural dentition. The Parkell and silk gave no significant differences to natural dentition. Similarly, subjects perceived that T-Scan(®) sensor and paper had the greatest effect on occlusion and were the least comfortable (P < 0·05). Thus, the very plastic T-Scan(®) sensor and very thick articulating paper both affected SEMG activity during occlusion and, therefore, may not provide valid tooth contact information for dental treatment. In conclusion, occlusal indicators can change SEMG activity during occlusion which may affect the validity of the measurements they provide.

Effect of different dental articulating papers on SEMG activity during maximum clenching

“…Our findings are substantially in agreement with the investigations of Forrester et al (Forrester et al , 2011): to the best of our knowledge, this is the only study that applied SEMG to reveal whether occlusal media might affect neuromuscular activity. According to the above-mentioned research, articulating paper of 200µm…”

“…Forrester et al also suggested that some specific material properties, like plasticity or stiffness, are able to modify the neuromuscular activity (Forrester et al , 2011): the validity of tooth contact registration appears to be affected not simply by indicator thickness but also by several other physical variables, or by the ability of the media to conform/adapt to the occluded surfaces. In our experiment a change from 200µm to 40µm, in fact, did not produce a significant effect on masseter or temporalis POC median values.…”

“…One study analyzed whether occlusal marking media affect the neuromuscular function: Forrester et al used a SEMG to record muscle activity of the temporalis anterior (TA) and superficial masseter (MS) during biting and clenching. According to their findings, an elicited muscle activity similar to that of natural occlusion was revealed exclusively for some types of tested occlusal indicators (i.e: silk strip) (Forrester et al , 2011). While Forrester et al provided information on maximum SEMG activity for TA and MS, the coordination of muscles between right and left sides was not assessed (Forrester et al , 2011).…”

Time-dependent analysis and representation of force distribution and occlusion contact in the masticatory cycle

“…Diese kann zu einer Beeinflussung der habituellen Okklusion führen. So folgerten Forrester et al [7] aufgrund eines gemessenen Einflusses von Okklusionsindikatoren aus Papier und T-Scan-Folien auf die Werte der Oberflächenmyographie während der Okklusion, dass die Verwendung dieser Indikatoren sich auf die Okklusion auswirken könne. Die Dicke der T-Scan-Folien liegen mit einer Dicke von 100 µm im mittleren Bereich der aktuell in der zahnärztlichen Behandlung verwendeten Folien µm; [15]).…”

“…Es ist anzustreben diese Dicke durch weitere Entwicklung zu reduzieren, doch dies ist aufgrund der kraftregistrierenden in die Folie eingebetteten Leitungsbahnen zum jetzigen Zeitpunkt noch nicht möglich. Ein weiterer Aspekt liegt in der Position [7] concluded that the use of these indicators may affect occlusion after having observed a measurable influence of occlusion indicators consisting of paper and T-scan films on surface electromyography values during occlusion. At 100 µm, the thickness of the T-Scan films lies within the average thickness range of films now used in dental practices µm) [15].…”