The comparison of dental arch forms obtained from teeth, alveolar bone, and the overlying soft tissue.

摘要

Objective: The objective of this study was to determine if a difference existed between arch forms created from tooth surfaces, alveolar bone, and overlying soft tissue.;Materials and Methods: The sampling population for this study was 18 individuals with a Class I malocclusion, mild crowding, and a CBCT image of good diagnostic quality. The Facial-axis point was chosen to create the arch form from teeth, the Bowman-Kau point was used to establish the arch form from the alveolar bone, and the WALA ridge was used to calculate the soft tissue arch form. A predetermined algorithm was then used to create five separate arch forms per patient. The arch forms were categorized according to shape and then superimposed on each other within an arch and the distance between tooth, bone, and tissue was calculated.;Results: For all characteristics of the tooth, bone, and tissue, the calculated distances were significantly different from 0. The distances between tooth and bone were larger for the mandible compared to maxilla (mean 3.30 vs. 2.48, respectively). The larger distances seemed to be located more posteriorly than anteriorly. The distance between tooth and tissue was largest for the second premolar (2.35±1.59), first molar (2.86±0.63), and second molar (3.25±0.87). A significant difference in distance between tooth and bone on both the maxilla and mandible was observed among race but limited to blacks vs. whites. There were no significant differences in distance between the tooth and either bone or tissue in regards to gender and age.;Conclusions: The arch form shapes obtained from the teeth, alveolar bone, and soft tissue are highly individual. However, there was a significant positive correlation found between the tooth, alveolar bone, and soft tissue arch forms. The overall distance between tooth and bone was greatest for the mandible compared to maxilla. The largest difference between tooth and bone were found at the canine and second molar in the maxillary arch followed by the first molar, first premolar and then second premolar. In the mandibular arch the largest difference was found at the first and second molars followed by the canine, first premolar, and second premolar.;Keywords: alveolar bone, arch form, WALA.