IADR Abstract Archives
CAD/CAM Machining Vibrations Related Zirconia Blank Shape and Initial Nesting
Objectives: This in vitro study evaluated the influence of zirconia blank design, framework and digital crown nesting location on CAD/CAM machining vibration.
Methods: Twenty-five round (Round group) and 15 D-shape (D-shape group) zirconia blanks were set in 5-axis CAD/CAM milling, 3 crown per blank were milled in the Round group (n=75) and 2 crown per blank were milled in D-shape group (n=30). Milling cutter tools 2.5, 1.0 and 0.6mm were used.
Vibration meter (VB-8200 Lutron Taiwan) was connected to the blank holder and data were collected
Results: Mean milling operation time per crown was 997.3±20.7 seconds. Mean cutter milling time were 210±7.5, 654±14.5 and 40±5.3 seconds for 2.5,1 and 0.6mm cutter tools respectively. In the Round group, location C exhibited the highest mean vibration values, with a significant statistical difference compared to location A (P<0.01). Location B exhibited higher mean vibration values that location A. Within the D-shape group, location C demonstrated higher vibration values more than location A, with no significant statistical difference (P=0.322). A higher mean vibration values were demonstrated in the Round compared to D-shape group, with no significant statistical difference (P=0.381).
Conclusions: Nesting location and zirconia blank design affects machining vibration. With no defined instruction by CAD/CAM companies, further investigation need to be done to inspect the long term effects on zirconia longevity.
Methods: Twenty-five round (Round group) and 15 D-shape (D-shape group) zirconia blanks were set in 5-axis CAD/CAM milling, 3 crown per blank were milled in the Round group (n=75) and 2 crown per blank were milled in D-shape group (n=30). Milling cutter tools 2.5, 1.0 and 0.6mm were used.
Vibration meter (VB-8200 Lutron Taiwan) was connected to the blank holder and data were collected
Results: Mean milling operation time per crown was 997.3±20.7 seconds. Mean cutter milling time were 210±7.5, 654±14.5 and 40±5.3 seconds for 2.5,1 and 0.6mm cutter tools respectively. In the Round group, location C exhibited the highest mean vibration values, with a significant statistical difference compared to location A (P<0.01). Location B exhibited higher mean vibration values that location A. Within the D-shape group, location C demonstrated higher vibration values more than location A, with no significant statistical difference (P=0.322). A higher mean vibration values were demonstrated in the Round compared to D-shape group, with no significant statistical difference (P=0.381).
Conclusions: Nesting location and zirconia blank design affects machining vibration. With no defined instruction by CAD/CAM companies, further investigation need to be done to inspect the long term effects on zirconia longevity.