title: Effect of simulated chairside grinding procedures using commercially available abrasive agents on the surface properties of zirconia.
abstract: OBJECTIVE
  The aim of the present study was to assess the change in physical properties (surface roughness, surface hardness and phase transformation) after surface grinding of zirconia by using three commercially available abrasives.
  
  
  METHODS
  Thirty sintered zirconia specimens were prepared and divided into three groups namely Group M (grinded using Mani Dia diamond bur standard grit), Group T (grinded using Tri Hawk diamond bur coarse grit) and Group P (grinded using Predator carbide bur). A customised assembly was used to follow a standardised protocol for surface grinding. The surface roughness, surface hardness and phase transformation was recorded before and after the grinding procedure.
  
  
  METHODS
  ANOVA and Bonferroni post hoc test were used to assess the values obtained after the testing the surface roughness and surface hardness.
  
  
  RESULTS
  The results of the present study revealed the average values of change in surface roughness as Group M (0.44μm) and Group T (1.235μm) and GroupP(-0.88μm). The average values of change in surface hardness were Group T (19.578 HV), Group M (46.722 HV) and Group P (36.429 HV). The change in surface hardness was not statistically significant. There was no phase transformation seen after the grinding procedure.
  
  
  CONCLUSIONS
  Carbide burs along with copious water irrigation when used to grind zirconia intra-orally produces has a polishing effect, minimal change in hardness & no phase transformation. The present study advocates the use of carbides for chair-side grinding of zirconia.
authors.affiliation: Department of Prosthodontics, M. A. Rangoonwala Dental College, Pune, Maharashtra, India.
authors.forename: Ramandeep
authors.initials: R
authors.lastname: Sandhu
authors.affiliation: Department of Prosthodontics, M. A. Rangoonwala Dental College, Pune, Maharashtra, India.
authors.forename: Mohit
authors.initials: M
authors.lastname: Kheur
authors.affiliation: Department of Oral Pathology, DPU University, DY Patil Dental College, Pimpri, Pune, Maharashtra, India.
authors.forename: Supriya
authors.initials: S
authors.lastname: Kheur
keywords: Carbides; chairside grinding; zirconia