Effect of surface finish and acidic medium on hardness and fracture toughness of zirconia reinforced lithium silicate (An In-vitro study)

Aim: To assess the effect of surface finish and acidic beverage (cola beverage) on hardness fracture toughness zirconia lithium silicate (Celtra press)Methodology: Total n=36 samples reinforced press) plates were divided into two main groups (n=18 glazed n=18 polished samples) then each group was subdivided equal according to immersion solution (artificial saliva & cola beverage). Surface facture measurements obtained for specimen, before after storage in solutions. micro measured by Vicker Micro-hardness tester. The using indentation method. Results: For Vickers results: Glazed group, it found that values recorded subgroup followed artificial immersed while lowest with Cola subgroup. Polished highest subgroup.Conclusion: Ageing medium negatively affected both Celtra press had prominent compared auto-glazed press.