The effect of dental and background facial attractiveness on facial attractiveness and perceived integrity and social and intellectual qualities.

INTRODUCTION: The purposes of this study were to assess the role of dental attractiveness in background facial attractiveness and to evaluate how facial and dental attractiveness influenced raters' opinions of the integrity, social attractiveness, and intellectual attractiveness of the models. METHODS: Photographs of male and female individuals rated by peers as unattractive, average, and attractive were combined with oral images of 4 different levels of dental attractiveness (Index of Orthodontic Treatment Need [IOTN] 1, 5, 7, and 10). Sixty-seven participants meeting the inclusion criteria were recruited as raters. Raters viewed closed-lip smile and open-lip, posed smile of 24 models and rated them for facial attractiveness and integrity and multiple social/intellectual attractiveness dimensions using a Visual Analog Scale. RESULTS: Intrarater reliability was fair to excellent. Analysis of variance showed significant 3-way interactions (P < 0.0001=aim 1; P < 0.005=aim 2) for model sex, facial attractiveness, and dental attractiveness. The contribution of dental attractiveness to facial attractiveness was not fixed or linear, but dependent on dental attractiveness level, background facial attractiveness, and model sex. For both sexes, dental impact on facial attractiveness was neutral or negative when teeth were less than ideal, beginning at IOTN 5 for all background facial attractiveness levels. The impact of dental attractiveness on integrity and social and intellectual attractiveness was also dependent on dental attractiveness level, background facial attractiveness, and model sex. Dental attractiveness can make dramatic differences in Average and Attractive male individuals. CONCLUSIONS: The impact of dental attractiveness on facial attractiveness and integrity and social and intellectual attractiveness was dependent on dental attractiveness level, background facial attractiveness, and model sex. The effect of dental esthetics on facial attractiveness was neutral or negative for both male and female individuals when there was a need for treatment (IOTN 5 or higher) for all levels of facial attractiveness. For both male and female models, lower dental esthetics had a greater effect on more attractive faces. Judgments about integrity and social and intellectual attractiveness were strongly affected by dental esthetics, and these effects were more dramatic and consistent for male faces.

Comparison of cone-beam computed tomography with multislice computed tomography in detection of small osseous condylar defects.

INTRODUCTION: Previous studies have indicated that orthodontic-grade cone-beam computed tomography (CBCT) images are limited when displaying small defects at the mandibular condyles for diagnosis. In this study, we investigated whether this limitation was inherent to CBCT by comparing CBCT with multislice computed tomography (CT), and whether image segmentation and color mapping could overcome this limitation. METHODS: Nine fresh pig heads (18 condyles, 36 medial and lateral condylar regions) were used. Small osseous defects (diameter and depth, 1.5 mm) were created at the medial and lateral regions of the condyles shown by gutta percha markers. After the overlying soft tissues were restored, the pig heads underwent orthodontic-grade CBCT scans (0.4-mm voxel size; i-CAT; Imaging Sciences International, Hatfield, Pa) and medical-grade CT scans (0.625-mm voxel size; LightSpeed; GE, Little Chalfont, Buckinghamshire, United Kingdom). Subsequently, 2 calibrated and blinded raters diagnosed the defect numbers in each condylar region from CBCT and CT images using Dolphin 3D software (Patterson Supply, St Paul, Minn) without image segmentation, and then 1 week later with the proprietary image segmentation and color mapping tools of Dolphin 3D. Condylar polyvinyl siloxane impressions were collected and evaluated by the same raters to obtain physical diagnoses. Rediagnoses were made on randomly selected subsamples to assess reliability. Using the physical diagnoses as references, the accuracy of imaging diagnosis was assessed and statistically compared among the varied imaging and analysis methods. RESULTS: Image diagnoses of all imaging and analysis methods showed good or excellent intrarater and interrater reliability values, except for those of the segmented CBCT images, which were substantially lower. The numbers of overdiagnoses and underdiagnoses per condylar region were not significantly different among the varied imaging and analysis methods (Wilcoxon tests, P >0.05), but classification functions demonstrated substantially lower sensitivity and accuracy with CBCT than with CT. Logistic regression also showed that CT had a significantly higher probability (odds ratio, 2.4) than CBCT in reaching the correct diagnosis, whereas use of the image segmentation and color mapping tool proprietary to Dolphin 3D did not improve the diagnostic accuracy from CBCT images. CONCLUSIONS: Even at a lower voxel size than medical CT images, orthodontic-grade CBCT images of mandibular condyles may be inherently less reliable and less accurate for the diagnosis of small condylar defects.