VARIATION IN MAXILLARY AND MANDIBULAR MOLAR AND INCISOR VERTICAL DIMENSION IN 12-YEAR-OLD SUBJECTS WITH EXCESS, NORMAL, AND SHORT LOWER ANTERIOR FACE HEIGHT

Maxillary and mandibular molar and incisor vertical dimensions were ev aluated in subjects who had excessive, normal, and short lower anterio r face height in relation to upper face height. Sexual dimorphism was also investigated. The dentoalveolar heights were compared between Cla ss I and Class II, dental and skeletal malocclusions. The sample was d rawn from the Burlington Growth Centre sample and consisted of 188 mal e and 156 female subjects at age 12 years, for whom lateral head films were available. This sample was classified into excessive, normal, an d short lower anterior face height, using the ratio upper anterior fac e height/lower anterior face height (UAFH/LAFH). The results showed th at the dentoalveolar heights are significantly different between faces with excessive, normal, and short lower anterior face heights, except for the lower posterior dental height, which showed no difference bet ween short and normal lower anterior face height subjects. All dentoal veolar heights are larger for male subjects except for the upper poste rior dental height. Dentoalveolar heights are similar between Class I and Class II dental and skeletal malocclusions. The upper teeth presen t a higher correlation to the UAFH/LAFH ratio than the lower teeth. St epwise regression analysis shows that 22% of the variation in the rati o is explained by the maxillary and mandibular molars and 41% is expla ined by the maxillary and mandibular incisors.