Tarek Anwar, Ashraf Mokhtar And Hanaa Zaghloul,

ABSTRACT
Statement Of The Problem: Bond Strength Is A Very Important Determinant Of Clinical Success Of Dental Prosthesis. However, With The Introduction Of Hybrid Ceramics, Further Information Is Needed Regarding The Use Of Universal Adhesives As Bonding Agents. Aim Of The Study: To Evaluate The Effect Of Surface Treatments And Universal Adhesives On The Micro-shear Bond Strength Of Hybrid Ceramics.

Materials and Methods: Two CAD/CAM Hybrid Ceramics (VITA Enamic (VE) And LAVA Ultimate (LU)) Were Used In This Study. Each Was Cut Into 4 Ceramic Specimens. The 8 Ceramic Specimens Were Divided Into 2 Groups (n=4) According To The Material. Each Group Was Subdivided Into 2 Subgroups (n=2) According To The Surface Treatment; Hydrofluoric Acid Etching (HF) And Sandblasting (SB). Each Subgroup Was Further Divided Into 2 Subgroups (n=1) According To The Universal Adhesive Used; Scotchbond Universal (SbU) And Futurabond U (FbU). Silane Was Applied On All Specimens For 60 Seconds. All Specimens Were Cemented With RelyX-Ultimate Resin Cement Through Microtubules. They Were Then Thermocycled As An Artificial Aging To Simulate The Oral Environment. Micro-shear Bond (?SBS) Test Was Performed On All Thermocycled Specimens Using The Universal Testing Machine.

Results: LU Showed A Higher Statistically Significant ?SBS Value Than VE (P<0.001). HF Showed A Better Statistically Significant ?SBS Value Than SB (P<0.001). No Statistical Significance Was Found Between The Two Tested Universal Adhesives (p=0.060).

Conclusions: 1) Ceramic Microstructure Had A Great Impact On The ?SBS. 2) HF Could Be Considered As A Reliable Surface Treatment Protocol Of Hybrid Ceramics. 3) The Presence Of MDP In The Universal Adhesive Did Not Have A Significant Influence On The Micro-shear Bond Strengths Measured.