The study investigates the presence of sexual dimorphism in the size of the permanent teeth among Chilean individuals. Mesiodistal and bucolingual diameters were measured in the teeth of 150 patients between 18 and 24 years old, 67 males and 83 females (excluded were third molars and pieces with large cavities and fillings). The largest were found in males; the differences in mean bucolingual diameters with p<0.05 were observed in pieces 1.1, 1.2, 1.3, 1.6, 1.7, 2.6, 3.3, 4.1, 4.2, and 4.5; and with p <0.01, the relevant pieces were to 4.4 and 4.7. With regard to mesiodistal dimensions, the only significant difference p <0.05 was found in piece 1.2. These results show that sexual dimorphism can be found in all group teeth.