IADR Abstract Archives
Development of a Chairside-Type Pressure Variable Sandblaster.
Objectives: Development of CAD/CAM system enabled the production of dental-restoration products through numerically controlled machining. Latest evidence proved blasting immediately before cementing is ideal to remove contaminations and prepare a sound surface for chemical treatment. Thus, a major concern hindering the use of CAD/CAM materials is to control alumina-blasting pressure at chairside. Therefore, the aim of this study was to develop a new pressure variable chairside sandblaster (CSB1) and perform validation tests to evaluate its performance.
Methods: To compare with CSB1, Miniblaster (Deldent) was pared with an external regulator as control. A PMMA plate was sandblasted with different pressure, 1) surface roughness after blasting, 2) area of blasting by measuring the diameter of blast area, 3) Amount of alumina used per second 4) Efficiency of roughness were recorded by using a laser scanning microscope. To evaluate clinical performance of CSB1, micro-tensile bond strength test with a CAD/CAM resin block (KATANA Avencia Block, Kuraray Noritake Dental) and an adhesive resin cement (Panavia V5, Kuraray Noritake Dental) were performed using 0.2 and 0.4 MPa on each device (n=30).
Results: Results of validation test were shown in Figure 1. Surface roughness of PMMA plates increased according with pressure in both devices, CSB1 tended to show higher Ra value at any pressure. Area of blasting also tend to increase as the pressure increased, however CSB1 showed smaller blasting area at any pressure. Bond strength tend to be higher at 0.4 MPa in both device. However clinically 0.4 Mpa does too much damage on CAD/CAM resin blocks. At 0.2 MPa, CSB1 showed higher bond strength comparing with Miniblaster. However, there were no significant difference between them.
Conclusions: A new pressure variable chairside sandblaster will be a unique and useful device for preparation of adherend surface with appropriate pressure for each CAD/CAM material at chairside.
Methods: To compare with CSB1, Miniblaster (Deldent) was pared with an external regulator as control. A PMMA plate was sandblasted with different pressure, 1) surface roughness after blasting, 2) area of blasting by measuring the diameter of blast area, 3) Amount of alumina used per second 4) Efficiency of roughness were recorded by using a laser scanning microscope. To evaluate clinical performance of CSB1, micro-tensile bond strength test with a CAD/CAM resin block (KATANA Avencia Block, Kuraray Noritake Dental) and an adhesive resin cement (Panavia V5, Kuraray Noritake Dental) were performed using 0.2 and 0.4 MPa on each device (n=30).
Results: Results of validation test were shown in Figure 1. Surface roughness of PMMA plates increased according with pressure in both devices, CSB1 tended to show higher Ra value at any pressure. Area of blasting also tend to increase as the pressure increased, however CSB1 showed smaller blasting area at any pressure. Bond strength tend to be higher at 0.4 MPa in both device. However clinically 0.4 Mpa does too much damage on CAD/CAM resin blocks. At 0.2 MPa, CSB1 showed higher bond strength comparing with Miniblaster. However, there were no significant difference between them.
Conclusions: A new pressure variable chairside sandblaster will be a unique and useful device for preparation of adherend surface with appropriate pressure for each CAD/CAM material at chairside.
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