title: Bialveolar protrusion in a Zimbabwean sample.
abstract: This study was undertaken to assess dentoalveolar relationships in a well-balanced sample of adult black Zimbabweans. Lateral cephalograms of 25 men and 25 women 18 to 38 years of age with Class I occlusions were obtained from the University of Zimbabwe. Twelve angular and 6 linear measurements were analyzed, and men and women were compared with the Student t test. No statistically significant difference was noted between the 2 sexes. The Zimbabwean sample had a low Frankfort-mandibular plane angle (19.6 degrees +/- 5.5 degrees ) with a receding chin as shown by the negative Pog-NB measurement (-0.7 +/- 1.5 mm). Both the maxilla (SNA = 88.5 degrees +/- 4.7 degrees ) and the mandible (SNB = 83.3 degrees +/- 4.4 degrees ) were prognathic, and the ANB difference was large (5.3 degrees +/- 2.7 degrees ). The maxillary incisors were more upright compared with those of white people as measured by the angle of the maxillary incisor to NA line (20.6 degrees +/- 7.7 degrees ), while the mandibular incisors were severely proclined (IMPA = 105.8 degrees +/- 6.0 degrees, L1-Apog = 6.9 degrees +/- 2.7 degrees, L1-NB = 37.6 degrees +/- 4.9 degrees ), and this proclination was considered to be compensatory to the prognathic maxilla.
authors.affiliation: Department of Orthodontics, University of Oklahoma Health Sciences Center, 1001 S.L. Young Boulevard, Oklahoma City, OK 73190, USA. Tarisai-Dandajena@ouhsc.edu
authors.forename: Tarisai C
authors.initials: TC
authors.lastname: Dandajena
authors.forename: Ram S
authors.initials: RS
authors.lastname: Nanda
mesh_terms: D000293:Adolescent; D000328:Adult; D044383:Black People; D002508:Cephalometry; D002680:Chin / Q000033:anatomy & histology; D003766:Dental Occlusion; D005006:Ethnicity; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007180:Incisor / Q000033:anatomy & histology; D008297:Male; D008334:Mandible / Q000033:anatomy & histology*; D008437:Maxilla / Q000033:anatomy & histology*; D013223:Statistics as Topic; D015030:Zimbabwe