Dental On average, approximately what is the dimension of the permanent maxillary canine at the widest mesiodistal diameter of the crown? A 5.5 mm. B 6.5 mm. C 7.5 mm. D 8.5 mm. 💡 Explanation On average, approximately what is the dimension of the permanent maxillary canine at the widest mesiodistal diameter of the crown? ✓ Correct Answer: C. 7.5 mm.