OBJECTIVE To study the bilateral differences in the thickness of the masseter muscles in untreated individuals with lateral crossbite, as well as in subjects with successfully treated functional lateral crossbite, at least three years after the end of treatment. MATERIALS AND METHODS Three groups of growing individuals were studied: (1) untreated group: 38 individuals with unilateral crossbit...

Background The mechanisms underlying tooth pulp hypersensitivity associated with masseter muscle hyperalgesia remain largely underinvestigated. In the present study, we aimed to determine whether masseter muscle contraction induced by daily electrical stimulation influences the mechanical head-withdrawal threshold and genioglossus electromyography activity caused by the application of capsaicin...

BACKGROUND Glucocorticoid has a direct catabolic effect on skeletal muscle, leading to muscle atrophy, but no effective pharmacotherapy is available. We reported that clenbuterol (CB) induced masseter muscle hypertrophy and slow-to-fast myosin heavy chain (MHC) isoform transition through direct muscle β2-adrenergic receptor stimulation. Thus, we hypothesized that CB would antagonize glucocortic...

Introduction: Myositis ossificans traumatica (MOT) is known mostly in the orthopedic literature as non-neoplastic, heterotopic bone formation within muscle or fascia, presumably due to acute trauma or repeated injury. Myositis ossificans traumatica of the masseter muscle is uncommon disease producing limitation of opening of the jaws. Purpose: To present a case of MOT of the masseter muscle in ...

Masseter muscle hypertrophy is a rare condition of unknown cause which is important in the differential diagnosis of head and neck masses, located in the cheek. Several treatment options reported for masseter hypertrophy, which range from simple pharmacotherapy to more invasive surgical reduction. Botulinum toxin type A is a powerful neurotoxin which is produced by the anaerobic organism Clostr...

Histochemical properties, muscle fiber cross-sectional area, muscle fiber length, and the oxidative capacity of masticatory muscles of female rhesus monkeys were assessed following alteration in functional length by an intraoral appliance or by detachment of the muscle. Experimental groups received the appliance only (A); the appliance and subsequent detachment of the masseter (AD); the applian...

bjective: The objective of this paper was to evaluate the specificity of masseter muscle palpation when compared to its electromyographic activity. Materials and Methods: Twenty-one young female adults, aged between 17 and 25, participated in this research. The speech therapy evaluation data were obtained by two speech therapists through masseter muscle palpation during isometric contraction, a...

Animal studies have suggested that tissue injury-related increased levels of glutamate may be involved in peripheral nociceptive mechanisms in deep craniofacial tissues. Indeed, injection of glutamate (0.1-1 M, 10 microl) into the temporomandibular region evokes reflex jaw muscle responses through activation of peripheral excitatory amino acid receptors. It has recently been found that this glu...

Introduction: Bilateral sagittal split osteotomy (BSSO) of mandible is vastly used in treatment of mandibular deficiencies and discrepancies. Since this method could affect esthetic as well as function, evaluating these effects from various aspects is crucial. This study assessed the effects of this technique on the function of masseter muscle, jaw movements, and sensory changes along with fail...

OBJECTIVE To investigate the relationship between vertical craniofacial morphology and masseter muscle thickness and mechanical advantage in children. MATERIAL AND METHODS The sample comprised 72 children (36 F, 36 M), 8.5-9.5 years of age, with various malocclusions and no previous orthodontic treatment. The thickness of the masseter was measured bilaterally by means of ultrasonography, and ...