TY - JOUR

T1 - Temporalis and masseter muscle activity in patients with anterior open bite and craniomandibular disorders

AU - Bakke, Merete

AU - Michler, L

PY - 1991

Y1 - 1991

N2 - Activity in temporalis and masseter muscles, and traits of facial morphology and occlusal stability were studied in 22 patients (19 women, 3 men; 15-45 yr of age) with anterior open bite and symptoms and signs of craniomandibular disorders. Facial morphology was assessed by profile radiographs, occlusal stability by tooth contacts, and craniomandibular function by clinical and radiological examination. Electromyographic activity was recorded by surface electrodes after primary treatment with a reflex-releasing, stabilizing splint. Maximal voluntary contraction was reduced compared to reference values, particularly in subjects with muscular affection, but maximal activity increased significantly when biting on the splint. Maximal voluntary contraction was positively correlated to molar contact and negatively to anterior face height, mandibular inclination, vertical jaw relation and gonial angle. Relative loading of the muscles was markedly increased during resting posture. It was concluded that reduced occlusal stability and long-face morphology were associated with weak elevator muscle activity with disposition overload and tenderness. The results also indicated that increase of occlusal stability might lead to increased muscle strength and possibly reduce risk of physical strain.

AB - Activity in temporalis and masseter muscles, and traits of facial morphology and occlusal stability were studied in 22 patients (19 women, 3 men; 15-45 yr of age) with anterior open bite and symptoms and signs of craniomandibular disorders. Facial morphology was assessed by profile radiographs, occlusal stability by tooth contacts, and craniomandibular function by clinical and radiological examination. Electromyographic activity was recorded by surface electrodes after primary treatment with a reflex-releasing, stabilizing splint. Maximal voluntary contraction was reduced compared to reference values, particularly in subjects with muscular affection, but maximal activity increased significantly when biting on the splint. Maximal voluntary contraction was positively correlated to molar contact and negatively to anterior face height, mandibular inclination, vertical jaw relation and gonial angle. Relative loading of the muscles was markedly increased during resting posture. It was concluded that reduced occlusal stability and long-face morphology were associated with weak elevator muscle activity with disposition overload and tenderness. The results also indicated that increase of occlusal stability might lead to increased muscle strength and possibly reduce risk of physical strain.

KW - Adolescent

KW - Adult

KW - Cephalometry

KW - Dental Occlusion

KW - Electromyography

KW - Facial Pain

KW - Female

KW - Humans

KW - Male

KW - Malocclusion

KW - Mandible

KW - Masseter Muscle

KW - Mastication

KW - Middle Aged

KW - Muscle Contraction

KW - Splints

KW - Temporal Muscle

KW - Temporomandibular Joint Dysfunction Syndrome

KW - Vertical Dimension

M3 - Journal article

C2 - 1871532

VL - 99

SP - 219

EP - 228

JO - Scandinavian Journal of Dental Research

JF - Scandinavian Journal of Dental Research

SN - 0029-845X

IS - 3

ER -