Evaluation of machining accuracy of zirconia Merlon fracture test models fabricated by subtractive and additive manufacturing
10.14815/kjdm.2024.51.1.53
- Author:
Heejung LEE
1
;
Ji-Myung BAE
;
Seunghan OH
Author Information
1. Department of Dental Biomaterials, College of Dentistry, Wonkwang University, Iksan, Republic of Korea
- Publication Type:Original Article
- From:
Korean Journal of Dental Materials
2024;51(1):53-62
- CountryRepublic of Korea
- Language:EN
-
Abstract:
The machining accuracy of zirconia prostheses fabricated by the subtractive (SM) and additive manufacturing (AM) was evaluated using the Merlon fracture test model in ISO 18675 (2022). The SM specimens were fabricated by a DWX-51D (Roland, Sydney, NSW, Australia) using two zirconia blocks (Katana Zirconia HT; KH, Katana Zirconia STML; KS). The AM specimens were prepared by a DLP type 3D printer INNI-Ⅱ (AON, Gunpo, Korea) using zirconia liquid slurry (INNI-CERA; PZ). The specimen STL image was acquired using a model scanner (E3, 3 Shape A/S, Copenhagen, Denmark). The machining accuracy of the specimens was analyzed by the RMS method superimposing the reference STL image and the specimen STL image in image analysis software (Geomagic Control X, 3D Systems, Rock Hill, SC, USA). From the results of the machining accuracy analysis, the KH and KS groups showed statistically significantly better machining accuracy (lower RMS) than the PZ group (P<0.05). The KH and KS groups showed higher machining accuracy as the thickness decreased, and the 0.2 mm and 0.3 mm experimental groups showed statistically significantly better machining accuracy than the 0.4 mm experimental group (P<0.05). On the other hand, the PZ group showed better machining accuracy as the thickness increased, with the 0.4 mm group showing statistically significantly better machining accuracy than the 0.2 mm and 0.3 mm groups (P<0.05). Within the limitation of this study, the thickness of the final zirconia prosthesis fabricated by additive manufacturing should be at least 0.4 mm for clinical use in dentistry.
