Resumen: Aim: To identify the reasons why first year student of Universidad San Sebastián decided to study Dentistry. Material and method: It is a non-experimental and transversal exploratory, descriptive study. A questionnaire composed of 20 questions focused on the reasons why students choose this career, was applied to student population in first year from Universidad San Sebastián (USS) 2016 in four locations (Santiago, Concepción, Valdivia, Patagonia). The sample (n= 308) was made up of all subjects who were available for assessment on the corresponding day. Association studies using the χ2 test and binary logistic regression were made and the regression equation was estimated using the forward Wald method. Finally, the Euclidean distance test was applied between all the answers correlated with the variables that were significant, using the concept of similarity. The level of significance was α≤0.05. Results: An association between the option choice and gender variables was observed. The χ2 test was significant (p = 0.012), which implies that both variables are associated, although the degree of association is low and significant (C = 0.141; p = 0.014). The regression model used classified 77.3% of the dependent variable data correctly and the estimated distances allowed to observe differences between the genders. Conclusion: The majority of students chose Dentistry as first choice and for intrinsic reasons. However, dental education should reinforce altruism in its students that chose Dentistry as a second choice and for extrinsic reasons.