title: Comparisons of chewing rhythm, craniomandibular morphology, body mass and height between mothers and their biological daughters.
abstract: OBJECTIVE
  To study and compare the relationships between mean chewing cycle duration, selected cephalometric variables representing mandibular length, face height, etc., measured in women and in their teenage or young-adult biological daughters.
  
  
  METHODS
  Daughters were recruited from local high schools and the University of Michigan School of Dentistry. Selection criteria included healthy females with full dentition, 1st molar occlusion, no active orthodontics, no medical conditions nor medication use that could interfere with normal masticatory motor function. Mothers had to be biologically related to their daughters. All data were obtained in the School of Dentistry. Measurements obtained from lateral cephalograms included: two "jaw length" measures, condylion-gnathion and gonion-gnathion, and four measures of facial profile including lower anterior face height, and angles sella-nasion-A point (SNA), sella-nasion-B point (SNB) and A point-nasion-B point (ANB). Mean cycle duration was calculated from 60 continuous chewing cycles, where a cycle was defined as the time between two successive maximum jaw openings in the vertical dimension. Other variables included subject height and weight. Linear and logistic regression analyses were used to evaluate the mother-daughter relationships and to study the relationships between cephalometric variables and chewing cycle duration.
  
  
  RESULTS
  Height, weight, Co-Gn and Go-Gn were significantly correlated between mother-daughter pairs; however, mean cycle duration was not (r(2)=0.015). Mean cycle duration was positively correlated with ANB and height in mothers, but negatively correlated with Co-Gn in daughters.
  
  
  CONCLUSIONS
  Chewing rate is not correlated between mothers and daughters in humans.
authors.affiliation: Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1078, USA.
authors.forename: Catherine
authors.initials: C
authors.lastname: Cho
authors.affiliation: Oral Health Sciences PhD Program School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1078, USA.
authors.forename: Ke'ale
authors.initials: K
authors.lastname: Louie
authors.affiliation: Department of Cariology, Restorative Sciences and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1078, USA.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Maawadh
authors.affiliation: Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1078, USA. Electronic address: geger@umich.edu.
authors.forename: Geoffrey E
authors.initials: GE
authors.lastname: Gerstner
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002508:Cephalometry; D003766:Dental Occlusion; D005145:Face / Q000033:anatomy & histology; D005260:Female; D006801:Humans; D008334:Mandible / Q000033:anatomy & histology* / Q000473:pathology; D008409:Mastication / Q000235:genetics / Q000502:physiology*; D008875:Middle Aged; D009035:Mothers; D012886:Skull / Q000033:anatomy & histology / Q000473:pathology; D014716:Vertical Dimension; D055815:Young Adult
keywords: Chewing cycles; Heritability; Human; Mandible; Mastication