Prediction of the size of unerupted canines and premolars in a Saudi Arab population.

The estimation of the size of unerupted permanent teeth is an essential aspect in treatment planning in the mixed dentition. The commonly used prediction methods of Moyers and Tanaka and Johnston are based on data from a sample of children of Northern European descent. The accuracy of these methods when applied to a different population is questionable. When we applied the Moyers probability tables to a limited sample of a Saudi Arab population, we found that the 35% level was a more accurate determinant than the commonly used 75% confidence level. Likewise, the prediction equations of Tanaka and Johnston overestimated the size of buccal segments in this population. The data illustrate the limitations of these methods when applied to a sample population of other than European descent. From this data, two linear regression equations were developed for tooth size prediction in Saudi Arab children.