Correlation between Innercanthal Distance and Mesiodistal Width of Maxillary Anterior Teeth in a Thrissur, Kerala, India, Population.

Abstract

Selecting and replacing missing teeth to natural proportions and esthetic preference of a patient in the absence of pre-extraction records is a very challenging task. Although facial analysis and proportions are well discussed in many populations, none exists for the Thrissur, Kerala, population. A prosthodontic rehabilitation for Kerala patients relying on other racial norms may result in dissonant facial proportions. Therefore, the purpose of this study was (1) to evaluate the validity of innercanthal distance as a guide in determining the mesiodistal dimension of six maxillary anterior teeth in a selected Malayalee population in the Thrissur Municipal Corporation area; (2) to check whether innercanthal distance undergoes dynamic changes over time as a result of aging; and (3) to evaluate whether there is a gender difference in the analyzed mean facial and dental proportions in this population. The study was conducted on 1,200 subjects in the Thrissur Municipal Corporation area. From five wards, 240 subjects were selected, out of which 120 were from the 18 to 25 years age group and 120 from the 40 to 50 years age group. Sixty males and females were selected from each group. The innercanthal distance was measured using a Digital Vernier Caliper, and alginate impressions were made to evaluate the size of maxillary anteriors. The data was analyzed statistically. The study showed that there is a high statistical significance between the innercanthal distance and the mesiodistal width of six maxillary anterior teeth in females (p < 0.01) and no significance in males. There was also dynamic changes in the innercanthal dimension and the mesiodistal width of maxillary anteriors with increase in age (p < 0.001). The difference in the mean of innercanthal distance between the genders was highly statistically significant, but no significance was found between the genders in the mesiodistal width of maxillary anteriors. Within the population evaluated, there was a high statistical significance in females between the innercanthal distance and the mesiodistal width of six maxillary anterior teeth, but not for males. Innercanthal dimension was found to undergo dynamic changes as age increases in both males and females, and it was much higher in males than in females. There was no statistical significance in the comparative evaluation of mesiodistal width of maxillary anteriors of males and females in the study. Teeth selection is a critical step in determining the outcome of successful prosthodontic treatment. No definite guidelines for the selection of maxillary anterior teeth pertaining to the Thrissur, Kerala, population exist. A prosthodontic rehabilitation of Thrissur, Kerala, patients relying on other racial norms will result in dissonant facial proportions. In selecting maxillary anterior teeth, the knowledge of racial norms will help specify certain esthetic and functional modifications in treatment plans, which might be specific to each group. Therefore, there remains an unquestionable need for a scientific and reliable method for maxillary anterior teeth selection, which can be applied on this group of Indian population.