PURPOSE: The aim of this study was to compare the marginal fit of cobalt-chromium crowns fabricated using conventional casts and computer-aided design/computer-assisted manufacturing (CAD/CAM) techniques at three stages of production: metal coping, after porcelain firing, and after cementation. MATERIALS AND METHODS: A total of 80 metal-ceramic crowns were fabricated using four different techniques: lost wax casting, milling, laser sintering, and milling of a presintered metal block. Marginal fit was measured at each manufacturing stage. RESULTS: The porcelain firing stage improved marginal fit. CAD/CAM techniques resulted in better marginal fit than did conventional casting techniques at all manufacturing stages. CONCLUSION: CAD/CAM techniques improve marginal fit.
PURPOSE: The aim of this study was to compare the marginal fit of cobalt-chromium crowns fabricated using conventional casts and computer-aided design/computer-assisted manufacturing (CAD/CAM) techniques at three stages of production: metal coping, after porcelain firing, and after cementation. MATERIALS AND METHODS: A total of 80 metal-ceramic crowns were fabricated using four different techniques: lost wax casting, milling, laser sintering, and milling of a presintered metal block. Marginal fit was measured at each manufacturing stage. RESULTS: The porcelain firing stage improved marginal fit. CAD/CAM techniques resulted in better marginal fit than did conventional casting techniques at all manufacturing stages. CONCLUSION: CAD/CAM techniques improve marginal fit.
Authors: Fabio Kricheldorf; Cleuber Rodrigo de Souza Bueno; Wilson da Silva Amaral; Joel Ferreira Santiago Junior; Hugo Nary Filho Journal: Eur J Dent Date: 2018 Jan-Mar