[Anatomical and histological characteristics of proximal surfaces of abutment teeth]

When the guide planes are formed on the proximal surfaces of abutment teeth the part of enamel is removed. Thickness of enamel and inclination of tooth are the factors that limit the possible tooth reduction. In this report anatomical and histological characteristics of proximal surfaces of the abutment teeth are analysed. Thickness of the enamel has been measured using the optical microscope for 280 prepared teeth. Measurements were performed on four zones of tooth's proximal surfaces, on the different distances from the top of enamel edge. Undercut of 420 proximal surfaces of tooth have been determined by micro-analyser with accuracy of 0.05 mm. By comparing the mean values of enamel thickness, in occlusal thirds, and undercut of proximal surfaces, it is possible to conclude that the formed guide plane remains in the enamel even after the removing of all natural undercuts.