Biomaterial Database

Electromyographic activity evaluation and comparison of the orbicularis oris (lower fascicle) and mentalis muscles in predominantly nose- or mouth-breathing subjects. 2006

Eliane Hermes Dutra, and Hiroshi Maruo, and Michelle Santos Vianna-Lara

Pontifical Catholic University of Paraná, Curitiba, Brazil. dutra@u.washington.edu

BACKGROUND The objective of this study was to evaluate and compare the electromyographic (EMG) activity of the orbicularis oris--lower fascicle (LOO) muscle and the mentalis muscle (MT)--in predominantly nose-breathing (PNB) and mouth-breathing (PMB) subjects. METHODS Thirty-four subjects, 22 PNB and 12 PMB, with Class II Division 1 malocclusions were evaluated in 2001 (T1) and again in 2004 (T2), 2 years 5 months later. The age ranges of the sample were 11 years to 14 years 11 months at T1, and 13 years 4 months to 16 years 6 months at T2. EMG activity was recorded with bipolar surface electrodes at rest and during 12 movements; data were processed and normalized by the EMG highest value. The Student t test and the Mann-Whitney nonparametric test were used to compare the mean values and the variables between the observation times. RESULTS Greater EMG activity of the MT was observed in the PMB group at rest and swallowing at T1 and T2. At T2, increased EMG activity of the LOO at blowing and pronunciation of the phoneme \b\ was observed as well as a greater increment of EMG activity of this muscle at blowing, pronunciation of the phoneme \m\, and chewing in the PMB group. In addition, greater EMG activity of the MT at chewing in the PMB group was observed at T2. CONCLUSIONS These results suggest that mouth breathing influences EMG activity of the LOO and MT muscles.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008312	Malocclusion, Angle Class II	Malocclusion in which the mandible is posterior to the maxilla as reflected by the relationship of the first permanent molar (distoclusion).	Angle Class II,Angle Class II, Division 1,Angle Class II, Division 2,Class II Malocclusion, Division 1,Class II Malocclusion, Division 2,Malocclusion, Angle Class II, Division 1,Malocclusion, Angle Class II, Division 2,Class II, Angle
D008409	Mastication	The act and process of chewing and grinding food in the mouth.	Chewing
D009055	Mouth	The oval-shaped oral cavity located at the apex of the digestive tract and consisting of two parts: the vestibule and the oral cavity proper.	Oral Cavity,Cavitas Oris,Cavitas oris propria,Mouth Cavity Proper,Oral Cavity Proper,Vestibule Oris,Vestibule of the Mouth,Cavity, Oral
D009058	Mouth Breathing	Abnormal breathing through the mouth, usually associated with obstructive disorders of the nasal passages.	Breathing, Mouth,Breathings, Mouth,Mouth Breathings
D009666	Nose	A part of the upper respiratory tract. It contains the organ of SMELL. The term includes the external nose, the nasal cavity, and the PARANASAL SINUSES.	External Nose,External Noses,Nose, External,Noses,Noses, External
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D002648	Child	A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL.	Children
D003679	Deglutition	The act of taking solids and liquids into the GASTROINTESTINAL TRACT through the mouth and throat.	Swallowing,Deglutitions,Swallowings
D004576	Electromyography	Recording of the changes in electric potential of muscle by means of surface or needle electrodes.	Electromyogram,Surface Electromyography,Electromyograms,Electromyographies,Electromyographies, Surface,Electromyography, Surface,Surface Electromyographies