HÜSEYİN ŞEKER, ŞEYMA KURTULUŞ, YENER OKUTAN, MÜNİR TOLGA YÜCEL
Meandros Medical and Dental Journal - 2023;24(4):315-320
Objective: To evaluate the effect of grinding with different diamond burs on the surface roughness (Ra) and flexural strength (FS) of hydrothermally aged zirconia. Materials and Methods: Ninety-eight bar-shaped monolithic zirconia specimens were prepared and divided into 7 subgroups according to grinding procedures: control, grinding with diamond burs (F; fine, M; medium, C; coarse); and grinding with zirconiaspecific diamond burs (ZF; fine, ZM; medium, ZC; coarse). All ground specimens were polished using a two-step zirconia polishing system. All specimens were subjected to autoclave aging. Ra was measured using a profilometer. One specimen per group was examined by scanning electron microscopy and X-ray diffractometry. A 3-point FS test was performed using a universal testing machine. Results: The lowest and highest Ra values were obtained in the control and C groups, respectively. The ZC group showed higher Ra values than the ZF and ZM groups. There was no difference between the FS values of the ZF and control groups. However, other grinding procedures led to decreased FS. Conclusion: Zirconia-specific fine diamond burs are recommended to maintain the mechanical strength of zirconia when clinical adjustments are needed.
