A surface topography study of the untreated and heat-treated zirconia dental crowns manufactured through CNC dental milling machine

Che Wan Jaafar, Che Wan Jaslan (2021) A surface topography study of the untreated and heat-treated zirconia dental crowns manufactured through CNC dental milling machine. Project Report. Universiti Teknikal Malaysia Melaka, Melaka, Malaysia. (Submitted)

	Text (24 Pages) A surface topography study of the untreated and heat-treated zirconia dental crowns manufactured through CNC dental milling machine.pdf - Submitted Version Download (1MB)
	Text (Full text) A surface topography study of the untreated and heat-treated zirconia dental crowns manufactured through CNC dental milling machine.pdf - Submitted Version Restricted to Repository staff only Download (4MB)

Abstract

Zirconia is one of the dental ceramics most widely used, which has become popular over recent years due to its excellent mechanical properties, which allow it to be used as a frame material to manufacture crowns, bridges or dental abutments and dental implant. On the other hand, the invention of CAD/CAM dental-field milling systems has made zirconia ceramics a standard material for dental restoration. However, the untreated CNC milled restoration shows moderate surface quality because of the reflective deflection between the workpiece and the tool cutter during milling operation. The aim of this study is to compare the surface topology of the untreated and heat-treated dental crown restoration manufactured through CNC dental milling machine. Y-TZP Zirconia block was used to manufacture 12 crown samples. The crown samples were divided into two groups, which 3 samples are for the untreated and 9 samples are for the heat-treated condition. 9 crowns samples were conducted for a heat treatment at three different temperature setting which is 850°C, 950°C, and 1050°C. At each temperature setting, three replication of the sample were adopted. After that, the selected samples were examined using a surface roughness tester. The measurement was carried out using two samples from each condition. After that, the selected crowns were sputter-coated. The surface topography comparison of the untreated and heat-treated crown restoration was executed using the Scanning Electron Microscope (SEM) machine with 50x power magnification. The result from this study showed the heat treatment of 850°C, 950°C, and 1050°C does not improve the surface quality of the crowns. The microstructure analysis shows the scallop-height effects still exist after the heat treatment. In conclusion, the temperature used in this study is not sufficient to improve the surface quality of the Zirconia dental crown. Also, the surface roughness tester plays a significant role in measuring the crown’s surface. As a recommendation, a higher temperature in between 1300°C-1500°C shall be used for heat treatment.

Actions (login required)

View Item