Osama T. Ali , Cherif A. Mohsen And Raiesa M, Hashem,

Objective: The Purpose Of This Study Was To Evaluate Two Different Methods Of Surface Treatment; Conventional And Simplifiedof Three Different Dental Ceramic Materials On Micro-shear Bond Strength (MSBS).

Materials and Methods: 120 Resin Cement Cylinder-shaped Samples (1mm In Diameter And 2 Mm In Height) Were Fabricated, 5 On Each Ceramic Disc (a Total Of 24 Ceramic Discs Were Used With 10 X14 Mm? Surface Area & Height Of 2 Mm), Samples Were Divided According To The Type Of Ceramic Plate Used Into 3 Groups (each Group N = 40), Group I: Resin Cement Samples Cemented On Lithium Disilicate Plate .? IPS E.max Cad?, Group II: Resin Cement Samples Cemented On Hybrid Ceramic Plate ?Vita Enamic? And Group III: Resin Cement Samples Cemented On Zirconia Reinforced Lithium Silicate Plate ?Celtra Duo?. Each Group Was Subdivided Into 2 Subgroups According To The Technique Of Ceramic Surface Treatment (each Subgroup N = 20), Subgroup I (Conventional Technique Using HF+S), Subgroup II (Simplifiedtechnique Using Monobond Etch & Prime). Then Each Subgroup Was Divided Into Two Classes (10 Samples Each), Class I Tested For Micro Shear Bond Strength (MSBS) Without Thermocycling, Class II Tested After Thermocycling. Resin Cement Was Mixed And Then Light-cured According To The Manufacturer?s Instructions. MSBS Tests Were Carried Out Using Universal Testing Machine (Instron USA). The Data Were Collected, Tabulated, And Statistically Analyzed.

Results: It Was Found That For Emax, The Conventional Technique (50.1?6.5) Showed Higher Values Of MSBS Than The Simplifiedtechnique (42.3?10.5) Before Thermocycling While The Values Were (40.7?9.3) For Conventional And (37.6?5.6) For Simplifiedafter Thermocycling Without A Significantdifference. For Vita Enamic, The Simplifiedtechnique (38?3.7) Showed Higher Values Of MSBS Than The Conventional Technique (29.8?3.7) Before Thermocycling While The Values Were (32?4.5) For Simplifiedand (25.2?5.8) For Conventional After Thermocycling With A Significantdifference. For Celtra Duo, The Simplifiedtechnique (50.6?5.7) Showed Higher Values Of MSBS Than The Conventional Technique (41.6?9.4) Before Thermocycling While The Values Were (36.3?4.5) For Conventional And (21.1?5) For Simplifiedafter Thermocycling With A Significantdifference. The Difference Between Groups Was Statistically Tested By Independent Samples T-test P Value < 0.05 Conclusion: Monobond Etch & Prime Has Shown Better Results To HF Acid And Silane Regarding Vita Enamic And Celtra Duo. It Can Be Safely Used Without Affecting The Clinical Performance Of The Restorations. For Emax: The Conventional Technique Using HF Acid And Silane Has Shown Better Results, Though Not Statistically Significant. Thermocycling Was Responsible For Bond Strength Decreases In All Groups, Regardless Of The Materials Or The Technique Of Surface Treatment.