Mohamed A. Hashem, Olfat S. Hassanein And Mohamed F. Haridy,
ABSTRACT
Aim: This Study Wa Carried Out To Investigate The Ultrastructure Of The ABRZ Formed By Different Adhesive Systems And To Measure The Micro-shear Bond Strength (?SBS) Of Two Self-etch Adhesive Systems, Might Be Of Value.
Materials & Methods: A Total Number Of 64 Extracted Caries-free Human Permanent Molars Were Collected For The Study. Teeth Were Examined And Thoroughly Washed With Water, Scaled With Periodontal Scaler To Remove Any Blood, Attached To Periodontal Tissues, Plaque And Calculus. The Teeth Were Stored In Saline Solution (changed Daily) At Room Temperature Until The Time Of Their Use. The Teeth Were Randomly Divided Into Two Main Groups (32 Each) According To The Adhesive System Used: Fluoride Containing (CLEARFIL Liner Bond F) And Non-fluoride Containing (CLERFIL S3 Bond). Each Group Was Randomly Subdivided Into Two Equal Subgroups (n=16) According To Time Elapsed After Bonding: Immediate After Bonding Or 4 Months Later Each Group Was Later Color Coded Before Storage Step. A Total Of Four Subgroups Were Investigated In This Study. For Each Sub-group, 64 Micro-cylinders On The Occlusal Surface Of Each Specimen Were Prepared For Micro-shear Bond Strength (?SBS) Testing.
Results: ClearFil Liner Bond F (24.4 �4.13 MPa) Showed A Higher Mean Micro- Shear Bond Strength ?SBS Than S3 Bond (19.77�5.96 MPa) With Statistically Significant P �0.001. For Immediate ?SBS ClearFil Liner Bond F Showed High Statistical Values (25.75� 4.71MPa) Than ClearFil S3 Bond Which Showed Mean (24.41� 3.55 MPa) Which Is Not Statistically Significant. For Delayed ?SBS ClearFil Liner Bond F Showed High Statistical Values Of Mean (23.20� 3.16 MPa) Than ClearFil S3 Bond Which Showed Mean (15.14� 3.89 MPa) Which Is Statistically Significant P �0.001. ESEM Scanning Showed A Clearly Recognizable Hybrid Layer, Which Was Thin But Defined, And Continuous. Short Resin Tags Formation With Limited Infiltration Into Dentinal Tubules In Superficial Dentin
Conclusion: The Incorporation Of Fluoride Into Self-etch Adhesives Was Advantageous Regarding Immediate And Delayed Bond Strength. Two-steps Self-etch Adhesives System Provided Superior Bonding Capabilities Compared To One Step Self-etch Adhesives. Fluoride-Containing Adhesives Might Have A Potential Effect On Bond Durability, Via Their Fluoride Release. These Adhesives Can Be Considered Advantageous, And Are Able To Bond Effectively To Dentin.
