RESUMO
OBJECTIVE: To investigate the relationship between nasal obstruction and lip-closing force. MATERIALS AND METHODS: Nasal airway resistance and lip-closing force measures were recorded for 54 Japanese females. The subjects were classified into normal and nasal obstruction groups according to nasal airway resistance values. Differences between the normal and nasal obstruction groups in lip-closing force were tested statistically. Correlation coefficients were calculated between the measures for the normal and nasal obstruction groups. RESULTS: Lip-closing force for the nasal obstruction group was significantly less than for the normal group (P < .05). In the normal group, nasal airway resistance did not correlate with lip-closing force, while in the nasal obstruction group a significant negative correlation was found between nasal airway resistance and lip-closing force (P < .05). CONCLUSIONS: Nasal obstruction is associated with a decrease in lip-closing force. When the severity of nasal obstruction reaches a certain level, the lip-closing force is weakened.
Assuntos
Lábio/fisiopatologia , Obstrução Nasal/fisiopatologia , Adulto , Resistência das Vias Respiratórias/fisiologia , Fenômenos Biomecânicos , Feminino , Humanos , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Nariz/fisiopatologia , Pico do Fluxo Expiratório/fisiologia , Rinomanometria , Adulto JovemRESUMO
The purpose of this study was to determine whether the development of masseter muscle activity at mandibular rest position is characteristic for different angle classifications. The sample consisted of 64 boys and 108 girls, aged ten to 18. Electromyographic (EMG) activity from the right and left masseter muscles was recorded using an EMG scanner. First or second order polynomials were used to separately model the age-related changes in resting muscle activity of each gender and Angle's classification. The EMG activity of Class I boys and girls were expressed in positive second order polynomials. The EMG activities of Class II and Class III subjects were expressed in first order polynomials, and the EMG levels in Class III subjects were lower than in Class II subjects. These results indicated that development of resting activity levels might distinguish and characterize the anteroposterior mandibular position relative to craniofacial region.
