Mavroskoufis F, Ritchie G M
J Prosthet Dent. 1980 Mar;43(3):254-7. doi: 10.1016/0022-3913(80)90398-4.
The evaluation of the collated results demonstrated that 86% to 90% of the subjects examined did not have identical dimensions or form of the left and right maxillary central incisors. In over 60% of these subjects the differences were quite substantial.