title: Relationship between frontal craniofacial morphology and horizontal balance of lip-closing forces during lip pursing.
abstract: The objectives of this study were to quantitatively evaluate the relationship between frontal craniofacial morphology and the horizontal balance of the lip-closing forces (LCF) generated during maximum voluntary pursing-like movements in patients with mandibular deviation. Thirty-one subjects (median age 25·4 ± 8·9 years) without a history of orthodontic treatment were randomly selected from among the orthodontic patients who visited our hospital. Lip-closing forces was recorded in eight directions during maximum voluntary pursing-like lip-closing movements. The subjects were divided into the deviation (two males and 11 females) and non-deviation groups (four males and 14 females). There was no significant difference in the total LCF between the deviation and non-deviation groups. In the deviation group, the mean LCF value on the deviation side of the upper lip was significantly lower than that detected on the non-deviation side of the upper lip, while the mean LCF value for the deviation side of the lower lip was significantly higher than that for the non-deviation side of the lower lip. In contrast, no significant difference in upper or lower lip LCF was detected between the deviation and non-deviation sides in the non-deviation group. The difference in the LCF generated in the lower lip between the deviation and non-deviation sides was significantly positively correlated with mandibular menton deviation and significantly negatively correlated with the difference in maxillary height between the deviation and non-deviation sides. These results suggest that the horizontal balance of the upper and lower lip LCF produced during pursing-like lip-closing movements in patients with mandibular deviation is related to frontal craniofacial morphology.
authors.affiliation: Department of Orthodontics, Matsumoto Dental University, Shiojiri, Nagano.
authors.forename: R
authors.initials: R
authors.lastname: Mizuno
authors.forename: K
authors.initials: K
authors.lastname: Yamada
authors.forename: M
authors.initials: M
authors.lastname: Murakami
authors.forename: K
authors.initials: K
authors.lastname: Kaede
authors.forename: Y
authors.initials: Y
authors.lastname: Masuda
mesh_terms: D000293:Adolescent; D000328:Adult; D005145:Face / Q000033:anatomy & histology*; D005149:Facial Expression; D005152:Facial Muscles / Q000502:physiology*; D005260:Female; D006801:Humans; D008046:Lip / Q000502:physiology*; D008297:Male; D008310:Malocclusion / Q000503:physiopathology*; D008334:Mandible / Q000503:physiopathology*; D009068:Movement / Q000502:physiology; D012886:Skull / Q000033:anatomy & histology*; D055815:Young Adult
keywords: frontal craniofacial morphology; lip pursing; lip-closing force; mandibular deviation; multidirectional measurement system