title: Nasal obstruction causes a decrease in lip-closing force.
abstract: OBJECTIVE
  To investigate the relationship between nasal obstruction and lip-closing force.
  
  
  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.
authors: Private practice, Kani, Japan.
authors: Kishio
authors: K
authors: Sabashi
authors: Kaei
authors: K
authors: Washino
authors: Issei
authors: I
authors: Saitoh
authors: Youichi
authors: Y
authors: Yamasaki
authors: Atsushi
authors: A
authors: Kawabata
authors: Yousuke
authors: Y
authors: Mukai
authors: Noriyuki
authors: N
authors: Kitai
mesh_terms: D000328:Adult; D000403:Airway Resistance / Q000502:physiology; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D008046:Lip / Q000503:physiopathology*; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D015508:Nasal Obstruction / Q000503:physiopathology*; D009666:Nose / Q000503:physiopathology; D010366:Peak Expiratory Flow Rate / Q000502:physiology; D025363:Rhinomanometry; D055815:Young Adult