Abstract
The purpose of this investigation was to utilize the thickness of toothcrown enamel of the permanent anterior teeth of the Japanese, as an index for preparation of abutment teeth for the laminate veneer technique.
The teeth used were upper and lower central and lateral incisors and canines (10 each) with relatively slight attrition, which were extracted prior to the investigation.
1. Enamel thickness was uniform along the tooth crown. However, enamel thickness of the upper central incisors were 1.1, 0.9 and 0.5 mm at their incisal, central and cervical, respectively. The enamel of the upper lateral incisor was thinner (approx. 0.1mm), and that of the upper canine was thicker (approx. 0.2 mm), than that of the upper central incisor.
2. The thickness of the lower canine enamel was nearly the same as that of the upper canine. In contrast, the enamel of the lower central and lateral incisors was thinner (approx. 0.2 mm) than that of the upper central incisor.
3. The tooth crown enamel became gradually thinner from the incisal to the cervical, and from the center to the proximal.
4. In order to preserve the enamel as much as possible, the preparation which follows the outer shape of the tooth crown is recommended.
As the enamel near the cervical is relatively thin, the greatest care must be take during preparation.
