Thai dentists' preferred maxillary anterior tooth width and width/height proportions

Abstract

Objective The purpose of this survey study is to provide information about the generally accepted standards for designing smiles using tooth proportion relationships for Thai dentists. Materials and methods A frontal image of a Thai smile was made and adjusted by a computer image manipulation program (Adobe Photoshop CS5) to produce a symmetric smile. The teeth were adjusted to three ratios (normal, tall and short teeth) and each ratio was made to three proportions (Golden, Preston and 70RED proportion). Eighteen survey sets of two different smiles were constructed. Two hundred forty two Thai dentists were asked to decide which smile in each set is more preferable. The results were analyzed with binomial test and Fisher’s Exact Test (α = 0.05) Result In normal width/height ratio teeth, no significant difference was found in the preferred tooth width. For the survey of short teeth, the golden ratio was the least preferable. When compared to the group with the same width proportion, the normal (78% width/height ratio) teeth were the most preferable. The analysis found that the preferences of Thai dentists may be influenced by field of mainly practice (7 out of 18 sets), gender (2 out of 18 sets) and years in practice(1 out of 18 sets). Conclusion The width/height proportion has more influence on the preference of Thai dentists than the tooth width proportion. And the field of mainly practice, gender and years in practice may also affect some preferences of Thai dentists.