Objective:

To determine the prevalence of agenesis in the current Chilean population, compare according to sex, affected tooth, skeletal class, and record microdontia of permanent upper lateral incisors.

Materials and methods:

In this cross-sectional descriptive study, the number of dental agenesis present in 278 panoramic radiographs of a total of 9207 patients who entered orthodontic treatment during 2017 in a private clinical center in Santiago de Chile was recorded.

Results:

A prevalence of agenesis of 3.02% was obtained, finding a higher frequency in lower second premolars, followed by upper lateral incisors. Females presented a higher amount of cases in comparison to males.

Conclusion:

The second premolars are the teeth with the highest prevalence of agenesis. The association of this alteration with some specific skeletal class was not evidenced. More studies are suggested to describe it´s prevalence in the third molars, beacause according to the evolutionary theory this tooth might eventually disappear.