Title
Analyzing Tonn’s formula for predicting permanent maxillary incisor widths in a South Tamil Nadu population
Authors
S. Chintu1,*, Soumya Rajan2, Janu S. Nair3, Amal S. Nair3, Anjana S. Nair3 & M. Mira Mohan1
Affiliation
1Department of Pedodontics and Preventive Dentistry, Sree Mookambika Institute of Dental Sciences, Kulasekharam, Tamil Nadu, India; 2Department of Pedodontics and Preventive Dentistry, Sri Sankara Dental College, Akathumuri, Varkala, Kerala, India; 3Department of Orthodontics and Dentofacial Orthopedics, Sree Mookambika Institute of Dental Sciences, Kulasekharam, Tamil Nadu, India; *Corresponding author
S. Chintu - E-mail: mangalliachintu@gmail.com
Soumya Rajan - E-mail: dr.soumyarajan@gmail.com
Janu S. Nair - E-mail: janunair01@gmail.com
Amal S. Nair - E-mail: amalsnair@gmail.com
Anjana S. Nair - E-mail: anjananair843@gmail.com
M. Mira Mohan - E-mail: mmiramohan@gmail.com
Article Type
Research Article
Date
Received September 1, 2026; Revised September 30, 2026; Accepted
September 30, 2026, Published September 30, 2026
Abstract
Given that tooth-size relationships are population-specific, the accuracy of Tonn's formula in predicting permanent maxillary incisor widths remains unverified for the South Tamil Nadu population. Therefore, it is of interest to evaluate the applicability of Tonn's formula for predicting the combined mesiodistal widths of permanent maxillary incisors in a South Tamil Nadu population. The mesiodistal tooth widths were measured by a digital Vernier calliper and the predicted maxillary incisor widths were calculated using Tonn’s formula. A total of 147 pairs of maxillary and mandibular dental casts were studied of children aged 9–18 years. The measured and predicted values showed no statistical difference (p = 0.842), indicating total agreement between the two methods and a very strong positive correlation (r = 0.923, p < 0.001) was found between the total mesio-distal widths of mandibular and maxillary incisors, which supports the predictive validity of the formula.
Keywords
Mixed dentition analysis, Tonn’s formula, incisor liability, tooth size prediction, South Indian population
Citation
Chintu et al. Bioinformation 22(9): 6015-6018 (2026)
Edited by
Vini Mehta
ISSN
0973-2063
Publisher
License
This is an Open Access article which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. This is distributed under the terms of the Creative Commons Attribution License.
