Department of Sociology, Anthropology and Gerontology, Youngstown State University
Friday Morning, 301E
Descriptive studies of the deciduous dentition morphology have been presented as an inclusion in permanent dentition studies (e.g. Aguirre et al. 2008), the focus of archaeological populations (e.g. Sciulli 1998) or on specific traits within modern populations (ie. Hanihara 1967). The present study examines 25 morphological traits in two African American samples from Memphis, TN and Dallas, TX (N= 218). These traits represent the most commonly used traits in population microevolution studies, describing various ancestral groups.
Results indicate there is a great deal of trait frequency variation between the two African American samples, as well as in comparison to European American samples. Traits, which vary in frequencies between the two sample populations, include maxillary lateral incisor shovel shape trait (69% vs. 46%), canine tuberculum dentale (40% vs. 22%), canine mesial ridge (3% vs 7%), and the maxillary posterior molar hypocone development (76% vs 92%).
Trait frequencies higher than previous studies include maxillary central incisor shovel shape trait (38%) and maxillary lateral incisor shovel shape trait (68%), canine tuberculum dentale (40%), maxillary molar complexity (20%), cusp six (33%) and seven (68%), and the Y-groove on the mandibular posterior molar (69%). Traits frequencies lower than previous studies include tuberculum dentale trait on both maxillary incisors (8% and 3%) and the hypocone development of the maxillary posterior molar (76%).
The level of trait expression is also informative when comparing populations, especially the molar traits. For example, Carabelli’s pit/fissure is the most common trait expression in African American samples, unlike European American samples.