PURPOSE To compare the onset time of two different rocuronium doses (0.6 and 0.9 mg x kg(-1)) and succinylcholine (1.5 mg x kg(-1), preceeded by 0.06 mg x kg(-1) rocuronium) at the masseter and the adductor pollicis muscle. METHODS In a randomized study, 60 ASA I or II adult women, 18-65 yr of age, were anesthetized with propofol and fentanyl and nitrous oxide in oxygen. Neuromuscular monitor...

PURPOSE To examine gene expression profile changes in the mouse masseter muscle tissue after repetitive electrical stimulation by using a DNA microarray technique. METHODS Nine male ICR mice aged 10 weeks were used. Each anesthetized mouse was secured on a platform in a supine position and the masseter muscle tissues on both sides were exposed. Bipolar electrodes were set on the right massete...

Palpation, a standard procedure in the diagnostic process of muscular pain conditions – myalgia, aims to provoke a muscular pain response. The origin of pain elicited by palpation is not fully understood. There is also a possibility that the pressure elicit response from mechanoreceptors in skin, sub mucosal tissue or periosteum, which may affect the validity of the method. The aim of this stud...

Idiopathic hypertrophy of the masseter muscle is a rare disorder of unknown cause. Some authors associate it with the habit of chewing gum, temporo-mandibular joint disorder, congenital and functional hypertrophies, and emotional disorders (stress and nervousness). Most patients complain of the cosmetic change caused by facial asymmetry, also called square face, however, symptoms such as trismu...

OBJECTIVES To report a case and discuss the mechanism of hemimasticatory spasm. DESIGN Case report. PATIENT A 37-year-old woman had a 3-year history of involuntary spasms of the right masseter muscle in association with localized scleroderma and facial hemiatrophy. Electrophysiological studies revealed a normal blink reflex. However, the masseter reflex and silent period were absent on the ...

BACKGROUND The purpose of this study was to compare the expression levels of p65 and S100 in the rat masseter muscle after the injection of different concentrations of botulinum toxin-A (BTX-A). METHODS We injected either 5 or 10 U of BTX-A into both masseter muscle of rats. As a control group, the same volume of saline was injected. After 14 days, the animals were sacrificed. Subsequently, a...

This relationship between the function of the muscles of mastication and craniofacial form was investigated in young adult monkeys by increasing the functional length of the elevator muscles of the mandible non-invasively by a bite-opening splint cemented to the maxillary dentition. The major adaptations to increased vertical dimensional were (1) marked superior and some anterior displacement o...

BACKGROUND Maintaining good physical fitness and oral function in old age is an important element of good quality of life. Disability-related impairment of oral function contributes to a deterioration of the diet of older people and to the reduction of their social activity. OBJECTIVES Investigate the association between masseter muscle tension, dental status, and physical fitness parameters....

Benign Masseteric Hypertrophy is a relatively uncommon condition that can occur unilaterally or bilaterally. Pain may be a symptom, but most frequently a clinician is consulted for cosmetic reasons. In some cases prominent Exostoses at the angle of the mandible are noted. Although it is tempting to point to Malocclusion, Bruxism, clenching, or Temporomandibular joint disorders, the etiology in ...

BACKGROUND The purpose of this prospective cross-over study is to evaluate the effect of bilateral balanced occlusion and canine guidance occlusion on the masseter muscle activity using implant-retained mandibular overdentures. METHODS After evaluation of 12 completely edentulous patients using cone beam computed tomography (CBCT), mucoperiosteal flaps were reflected exposing the mandibular i...