Compare the mechanical properties and tightness of 3D printing and CNC cutting crowns
AIM:Compared with the differences in bending strength,fracture toughness(KIC)and Vickers hardness(Vhn)between 3D printing technology and CNC cutting specimens.To evaluate the difference in crown tightness between the two processes.METHODS:The universal mechanical test machine is used to test the bending deformation and KIC of ceramics,The Vickers hardness instrument is used to test the ceramic hardness resistance.Meanwhile,Microleakage was used to evaluate the marginal adaptation of dental restorations.RESULTS:The bending strength of the 3D printing group was significantly lower than that of the CNC cutting group,but it had reached(678.32±70.52)Mpa,which met the flexure strength requirements of three-unit prosthetic base ceramics containing molars.The fracture toughness value of 3D printing group and CNC cutting group is(8.63±0.94)、(6.63±1.40)MPa m1/2.The hardness of 3D printing and CNC cutting group is(17.61±0.68)、(15.80±0.41)GPa.The 3D printing group had higher fracture toughness and hardness in the CNC cutting group,there was a difference between the two groups(P<0.05),and both groups met the clinical requirements.CONCLUSION:The strength、hardness、fracture toughness and marginal adaptation of 3D printed zirconia all-ceramic crowns can meet the clinical requirements,which provides a reasonable basis for the application of 3D printing in clinical practice,but it also needs further research.
3D printingcomputer numerical control-millingzirconia all-ceramic crownsmechanical propertymicroleakage
NETL
NSTL
万方数据
