Is Tanaka-Johnston mixed dentition analysis an applicable method for a Saudi population?

Area of Science:

• Dentistry
• Orthodontics
• Anthropology

Background:

• Accurate prediction of unerupted tooth dimensions is crucial in orthodontics.
• Existing prediction methods may not be universally applicable across diverse populations.

Purpose of the Study:

• To evaluate the accuracy of the Tanaka and Johnston prediction method for tooth width in a Saudi population.
• To develop population-specific regression equations for predicting tooth dimensions.

Main Methods:

• A sample of 409 orthodontic study models from Saudi individuals was analyzed.
• Mesiodistal widths of mandibular incisors, canines, and premolars were measured.
• Predicted widths from the Tanaka and Johnston equation were compared to actual measurements.

Main Results:

• Significant gender differences were found in canine and premolar widths (p<0.001).
• The Tanaka and Johnston method significantly overestimated tooth widths in the Saudi sample (p<0.001).
• Mandibular incisor width effectively predicted unerupted canine and premolar widths (r=0.51-0.61).

Conclusions:

• The Tanaka and Johnston prediction equation is not accurate for the Saudi population.
• New, gender-specific regression equations were formulated for improved tooth width prediction in Saudis.