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...

OBJECTIVES To estimate the association of initial masseter muscle thickness with treatment outcomes using functional appliances and the effect of treatment on masseter muscle thickness. MATERIAL AND METHODS Twenty-two children, aged 8-12, with skeletal and dental class II relationships and increased overjet were treated with twin-block appliances for 9-17 months, until a class I molar relatio...

The jaw, suprahyoid, and extrinsic tongue muscles were studied in 11 genera, belonging to five tribes, of Old World squirrels. Significant variation in most of the adductor muscles is evident. The most primitive state of sciuromorphy is seen in the African tree squirrels Paraxerus and Funisciurus, especially as reflected in the anterior deep masseter. A derived state of sciuromorphy is found in...

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....

Botulinum toxin (BTA) is a bacterial-derived extract that can inhibit muscle contraction, acting directly on the absorption of acetylcholine. Thanks to this property, botulinum has been used in aesthetic and general medicine for several years. Nowadays, use being deepened address problem bruxism. In scoping review, results studies literature last 10 years were analyzed. Indeed, 12 reports (foun...

Objectives: Different theories have been suggested to define factors involved in skeletal and craniofacial morphology. Many of these theories explain that the bone morphology is the result of the bone tissue capability to adapt in response to biomechanical forces exerted during growth. Also, it seems logical to hypothesize that there is a relationship between biomechanical connections of muscle...

We report a case of congenital fistula from ectopic accessory parotid gland to the cheek demonstrated by CT sialography and CT fistulography. The right parotid gland was abnormally located lateral to masseter muscle. The fistula was arising from an ectopic accessory parotid gland with ectopic duct positioned anterior to masseter muscle. CT sialography and CT fistulography were very helpful in t...

Most clinicians throughout the world are probably unaware of the existence of masticatory muscle tendon-aponeurosis hyperplasia (MMTAH), potentially leading to misdiagnoses such as temporomandibular joint disorder (TMD). Here, we introduce this disease from the viewpoint of education. In February 2013, a 39-year-old woman presented with limited mouth opening. Her facial configuration was charac...

BACKGROUND Since type A botulinum toxin was first reported for the treatment of masseter muscle hypertrophy in 1994, there have been few reports about cosmetic indications for contouring procedures of the lower face with injection of botulinum toxin type A, and this procedure remains unpredictable. OBJECTIVES This study attempted a quantitative prospective analysis of reduction of masseter mu...

In East Asia, a square face is considered unattractive, and mandibular contouring surgery is commonly used to give a smooth contour to the lower jaw. Mandibular contouring surgery occasionally involves not only osteotomy of the mandibular angle but also resection of the masseter muscle via an intraoral approach. This type of mandibular contouring surgery poses a risk of injury to the premassete...