Soft-Tissue Profile Comparisons Between African-Americans and Caucasians in Kentucky

Objectives: Although previous studies have highlighted a number of significant differences in the soft-tissue profiles of different ethnic groups, comprehensive soft-tissue norms for non-Caucasians are rare in peer-reviewed literature. This retrospective study was designed to measure and compare the soft-tissue profiles of African-American and Caucasian orthodontic patients treated at the University of Kentucky (UK) between 2000-2014. Our study findings will establish a comprehensive set of African-American soft-tissue norms for clinical diagnosis and treatment planning.
Methods: Approval for this study was obtained from the UK IRB. A total of 242 patients between the ages of 7-23 were identified for the study in archived records (74 African-American females, 48 African-American males, 67 Caucasian females, and 53 Caucasian males). Only patients diagnosed with dental Class I first permanent molars and canines were included in the study. Patients with dental Class II or III malocclusions, six or more missing teeth, skeletal asymmetries, craniofacial syndromes or deformities were excluded. Soft-tissue features are currently being traced on pre-treatment lateral cephalograms using Dolphin Imaging software version 11.8. The 21 soft-tissue measurements selected for comparison are derived from the Legan/Burstone Analysis and/or the UK Cephalometric Analysis. Intra-rater reliability, Dahlberg error, will be determined for the principal investigator via the retracing of 20 randomly-selected cephalograms one month after the initial tracings are complete. Means, standard deviation and range values will be determined for each measurement within each group. Measurement mean distribution will be tested for normality with a Shapiro-Wilk test. Assuming normal distribution, an unpaired t-test will be used to determine significant differences between the two ethnic groups. Modified (layered) Bonferroni correction for multiple means testing.
Results: Data are currently being gathered and analyzed.
Conclusions: Complete study findings will be presented, including suggested soft-tissue norms for African-Americans located in Central Kentucky.