The dimension analysis of prepared natural teeth for developing customized zirconia block / 대한치과보철학회지

ABSTRACT

PURPOSE: Unpredictable shrinkage of zirconia during sintering process causes discrepancy. Therefore, there have been attempts to reduce discrepancy by milling zirconia after sintering. However, due to the hardness of sintered zirconia, milling takes longer time, causes damage to the machine and causes chip formation. With customized zirconia block using the mean dimension of prepared natural dentition, it is expected to overcome these shortcomings. MATERIALS AND METHODS: The mean dimension of prepared natural dentition was analyzed as STL file after scanning of prepared teeth treated at SNUDH. The transverse, frontal and sagittal planes were set using Mimics and Photoshop. 3D volume was projected on each plane, and the outer line was measured through external tangent line, and the inner line was measured through inflection point of tangent line. RESULTS: The mean height of prepared incisal (N = 57) is 6.60 ± 1.05 mm, mesiodistal length is 2.98 ± 0.73 mm, buccolingual length is 2.04 ± 0.73 mm. The mean height of prepared premolar (N = 15) is 5.37 ± 1.49 mm, mesiodistal length is 4.10 ± 1.78 mm, buccolingual length is 5.86 ± 1.55 mm. And the mean height of prepared molar (N = 13) is 5.11 ± 1.29 mm, mesiodistal length is 6.80 ± 1.18 mm, buccolingual length is 7.34 ± 1.40 mm. CONCLUSION: Using the mean dimension of prepared natural dentition, it is expected to be able to fabricate customized zirconia block.