Maged Yehia Elsaid, Mostafa Abd Elhameed Hassan And Rehab Khalil Safy .,

ABSTRACT


Aim: The Purpose Of This Study Was To Investigate The Effect Of Different Surface Treatments And Different Types Of Resin Composites On The Micro-tensile Bond Strength And Adaptation Of Repaired Microhybrid Resin Composite.

Materials & Methods: A Total Number Of 90 Cylinders Of Microhybrid Resin Composite Were Created And Stored In Artificial Saliva For Six Months At Room Temperature. After Storage The Cylinders Were Removed From The Artificial Saliva And Were Divided Randomly Into Three Groups According To Type Of The Resin Composite Material Which Was Used For Repair (M1; Bulk-fill Resin Composite, M2; Flowable Resin Composite And M3; Microhybrid Resin Composite). Each Group Was Subdivided Into Three Subgroups According To Surface Treatment Used (T1; Etching And Rinsing Without Application Of Adhesive, T2; Etching And Rinsing Followed By Application Of Adhesive And T3; Self-etch Adhesive System) (n=10). Another Cylinder Of Repairing Resin Composite Material Was Fabricated On The Surface Of The Aged Cylinders After Application Of Surface Treatment. For Micro-tensile Bond Strength (?TBS) Assessment 45 Specimens Were Serially Sectioned Creating Beams. The Prepared Beams Were Tested Individually Using A Universal Testing Machine. Maximum Tensile Stresses Were Recorded In Mega Pascal (MPa). For Assessment Of Adaptation, The Remaining 45 Specimens Were Immersed In A Dye Solution And The Interfacial Gap Distance Was Measured Through A Stereomicroscope.

Results: The Highest Micro-tensile Mean Load Value Was Recorded When The Bulk-fill Resin Composite Was Used As A Repairing Material After Surface Treatment Of The Aged Resin Composite With One-step Self-etch Adhesive System. The Highest Adaptation Mean Value Was Recorded When The Flowable Resin Composite Was Used As A Repairing Material After Surface Treatment Of The Aged Resin Composite With One-step Self-etch Adhesive System. Conclusion: Surface Treatment Of The Aged Resin Composite With One-step Self-etch Adhesive System Improved The Micro-tensile Bond Strength And Adaptation Between Aged Resin Composites And Both Bulk-fill And Flowable Resin Composite As Repairing Materials.