Introduction:

dental caries, periodontal diseases and malocclusions are, in that order, the reported oral conditions with the highest prevalence worldwide according to the World Health Organization (WHO). Dental caries is considered a multifactorial, dynamic and chronic disease, in which intervene extrinsic factors that may be associated with the disease.

Objective:

to relate Decayed, Missing, and Filled Teeth Index with the limitation when smiling in 12-year-old schoolchildren from "El Vecino" Parish, in Cuenca city, Ecuador, 2016.

Methods:

a descriptive, cross-sectional, relational and retrospective study was carried out. The sample consisted of 279 files registered in the database of the Research Department of the Dentistry career from the Catholic University of Cuenca, belonging to the study of the Epidemiological Map of Oral Health, 2016.

Results:

100% of the sample had some experience of caries, while 77.8% showed no limitation when smiling, which demonstrates a moderate dependence relationship between the Decayed, Missing, and Filled Teeth Index and the limitation when smiling.

Conclusions:

a very high level of severity of the Decayed, Missing, and Filled Teeth Index was reported in a quarter of the sample; the relationship between the Decayed, Missing, and Filled Teeth Index and the limitation when smiling had a moderate dependence between the two variables in both genders.