The Effect of an Occlusal Stabilization Splint and the Mode of Visual Feedback on the Activity Balance Between Jaw-Elevator Muscles During Isometric Contraction

Abstract

The aim of the present study was to gain an insight into the influence of a vertical bite-rise (clenching in intercuspal occlusion vs. clenching on an occlusal stabilization splint), the mode of visual feedback (VF; obtained from the compound masseter signal, from the compound anterior temporalis signal, or from the compound signal of both masseter and anterior temporalis muscles) and the EMG clenching level (10% MVC and 50% MVC) on the muscle balance between the masseter and the anterior temporalis muscles. The muscle balance was quantified as the logarithmic value of the ratio between the summated mean rectified EMG activity of the masseter muscles and this activity of the anterior temporalis muscles. The muscle balance was influenced significantly by the mode of VF (p < 0.01), the muscle balance shifting toward the group of muscles from which VF was obtained. When VF was obtained from the masseter muscles, a decrease in the anterior temporalis EMG activity was observed when the vertical dimension was increased (p < 0.05-0.01). When VF was obtained from the anterior temporalis muscles, the activity of the masseter muscles was raised with respect to that of the anterior temporalis muscles during clenching with a vertical bite-rise (p < 0.05-0.01). When VF was obtained from both groups of muscles, the masseteric EMG activity increased, whereas the anterior temporalis EMG activity decreased. Hence, regardless of the mode of VF, a relatively lower activity level of the anterior temporalis muscles was achieved after insertion of an occlusal stabilization splint. The therapeutic effect of a stabilization splint may therefore, at least in part, be related to a reduced activity in the anterior temporalis muscles.

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References

Academy of Denture Prosthetics (1977). Glossary of prosthodontic terms. St.Louis (MO) : Mosby.

Buchner R. , Van der Glas HW , Brouwers Jeig , Bosman F. (1992). Electromyographic parameters related to clenching level and jaw-jerk reflex in patients with a simple type of myogenous cranio-mandibular disorder. J Oral Rehabil 19:495-511.

Carlsson GE , Ingervall B. , Kocak G. (1979). Effect of increasing vertical dimension on the masticatory system in subjects with natural teeth. J Prosthet Dent 41:284-289.

Cochran WG , Cox GM (1957). Experimental designs. New York : John Wiley and Sons, Inc.

De Boever JA (1979). Functional disturbances of the temporomandibular joint. In: Zarb GA , Carlsson GE , editors. Temporomandibular joint function and dysfunction. Copenhagen (Denmark): Munksgaard, 193-214.

Desmedt JE , Godaux E. (1979). Recruitment patterns of single motor units in the human masseter muscle during brisk jaw clenching. Arch Oral Biol 24:171-178.

DuBrul EL (1980). Sicher's oral anatomy. St.Louis (MO): The C.V. Mosby Company.

Holmgren K. , Sheikholeslam A. , Riise C. (1985). An electromyographic study of the immediate effect of an occlusal splint on the postural activity of the anterior temporalis and masseter muscles in different body positions with and without visual input . J Oral Rehabil 12:483-490.

limenez ID (1987). Dental stability and maximal masticatory muscle activity. J Oral Rehabil 14:591-598.

10.

Kroon GW , Naeije M. , Hansson TL (1986). Electromyographic power-spectrum changes during repeated fatiguing contractions of the human masseter muscle. Arch Oral Biol 31:603-608.

11.

Manns A. , Miralles R. , Palazzi C. (1979). EMG, bite force, and elongation of the masseter muscle under isometric voluntary contractions and variations of vertical dimension . J Prosthet Dent 42 :674-682.

12.

Naeije M. , Hansson TL (1991). Short-term effect of the stabilization appliance on masticatory muscle activity in myogenous craniomandibular disorder patients . J Craniomandib Disord Oral Fac Pain 5:245-250.

13.

Naeije M. , McCarroll RS , Weijs WA (1989). Electromyographic activity ofthe human masticatory muscles during submaximal clenching in the intercuspal position. J Oral Rehabil 16:63-70.

14.

Rugh JD , Solberg WK (1979). Psychological implications in temporomandibular pain and dysfunction. In: Zarb GA , Carlsson GE , editors. Temporomandibular joint function and dysfunction. Copenhagen (Denmark): Munksgaard, 239-268.

15.

Van Eijden Tmgj, Brugman P. , Weijs WA , Oosting J. (1990). Coactivation of jaw muscles: Recruitment order and level as a function of bite force direction and magnitude. J Biomechan 23:475-485.

16.

Visser A. , McCarroll RS , Naeije M. (1992). Masticatory muscle activity in different jaw relations during submaximal clenching efforts. J Dent Res 71:372-379.

17.

Yemm R. ( 1985). A neurophysiological approach to the pathology and aetiology of temporomandibular dysfunction. J Oral Rehabil 12:343-353.