A pilot study to analyze the uniqueness of anterior teeth using a novel three-dimensional approach

Anonymized upper and lower dental models of 20 patients who had completed orthrodontic treatment with good clini- cal results were scanned by hand using an intra-oral three-dimensional scanner. The three-dimensional scans were then cropped to include only the incisal 2 mm of the six anterior teeth. The edited images were subsequently imported into the three-dimensional analysis software, and a best fit alignment analysis of test and reference scans was undertaken using approximately 10,000 reference points. The distance between each reference point of both scans was measured, and 0.1 mm was the threshold criteria used to accept as matches. A pictorial map produced by the software illustrated both quantitative and qualitative data from 420 comparisons undertaken. The software was able to identify matches amongst different software files of the same scan and different scans of the same models. There was a complete mismatch between the scans of pre- and post-treat- ment models. There were no perfect matches amongst the different post-treatment three-dimensional scans. However, there were close similarities between four upper and seven lower models using the 0.1 mm threshold. Using stringent criteria, we have shown that the human anterior dentition is unique within this study population