A comparative study for the selection of anterior teeth by correlating the combined width of six maxillary anteriors to the curved distance measured on occlusal rims for Indian and Malaysian population

Abstract

Statement of the Problem: The distance between the canines is usually measured around the curvature of the wax occlusal rim; however, most manufacturer's mold charts provide the measurements of the artificial six anterior teeth as if they were on a straight line. Purpose: To assess the correlation between combined mesiodistal width (CW) of six maxillary anterior teeth and curved distance (CD) from distal surface of one canine to the other measured on the occlusal rim for Indian and Malaysian population. Materials and Methods: Seventy maxillary dentate casts were used (35 Indians and 35 Malaysians). The width of each maxillary anterior tooth was measured using modified Vernier caliper. The CW of six anterior teeth corresponded to the sum of the width of each anterior tooth. Putty indexes were made on the labial surface of anterior teeth, and the casts were made partially edentulous by trimming the six anterior teeth. Occlusal rims were prepared with the help of index. The CD between the distal surface of one canine to the other was measured on the rim by ligature wire adapted across the center of the rim and measured using the Vernier caliper. Unpaired t -test/Pearson correlation and linear regression analysis were used to find out the correlation. Results: Pearson correlation test for CW and CD was statistically significant for both the groups (Indians [ r = 0.820] and Malaysians [ r = 0.941]) linear regression equations were obtained: Indians (CD = 1.1 [CW] − 12.4) and Malaysians (CD = 1.1 [CW] − 11.0). Conclusion: The CD can be related to the CW of six anterior teeth for both (Indians and Malaysians) and can be used in the clinical practice for selecting the comparatively accurate mold size. In broader sense, the CD for Indians will be 6-8 mm greater than the combined width, while for Malaysians, it will be 5-7 mm greater than the combined width.