title: Comparison of craniofacial morphology in monozygotic twins with their siblings.
abstract: Lateral cephalometric radiographs from 33 families of monozygotic twins and their siblings were digitized. Eight skeletal parameters were measured: FA to SN, SNA, SNB, ANB, angle of convexity, mandibular plane to SN angle, Y axis and pogonion to NB distance. Monozygotic twin pairs and their siblings showed a normal distribution pattern for all the skeletal parameters, except the pogonion to NB distance measurement. There was found to be a statistically significant correlation between age and facial angle and ANB. A familial aggregation effect was found for SNA, ANB and angle of convexity. Some genetic influence was found for FA, mandibular plane angle and Y axis, while the Pg to NB distance showed neither genetic influence, nor a familial aggregation.
authors.affiliation: Naval Dental Clinic, San Diego, CA.
authors.forename: M S
authors.initials: MS
authors.lastname: Sorin
authors.forename: T C
authors.initials: TC
authors.lastname: Ramsey
authors.forename: T C
authors.initials: TC
authors.lastname: Hart
authors.forename: F H
authors.initials: FH
authors.lastname: Farrington
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000704:Analysis of Variance; D002508:Cephalometry; D002648:Child; D002675:Child, Preschool; D005145:Face / Q000033:anatomy & histology*; D005190:Family; D005260:Female; D006801:Humans; D008297:Male; D008445:Maxillofacial Development; D012886:Skull / Q000033:anatomy & histology*; D014430:Twins, Monozygotic