The objective of this study was to describe transversal dimensions of the dental arches, bite force and facial index in three ethnic groups representative of Colombia. The sample size included 197 adolescents, 12 to 14 year old, 33% mestizo, 35% of African ancestry and 32% Amazon Indian; 50.3% male and 49.7% female. The comparative analysis to determine differences between ethnic groups was made by the Kruskal Wallis test and then the Principal Component Analysis was used to establish the pattern of measurements identifying ethnic characteristics. All measurements showed statistically significant differences among ethnic groups except facial height (p= 0.157). It was evidenced that Amazon indian have a higher bite force (p<0.05) than the other twoethnic groups. Regarding dental arch transversal dimensions, Amazon Indian have a higher arch transversal width with a length average of 44.1 mm. This length was greater than mestizo adolescents (M= 36.7 mm) and Afroamerican (M= 38.3 mm). In conclusion, the amazon Ticuna Indian ethnia has a significantly higher bite force, higher dental arch transversal width and higher bizygomatic width than the other two ethnic groups considered.

KEY WORDS: Facial biotype; Bite force; Dental arch; American ethnia.