Faeiza D. Diryag, Noha A. El-Wassefy, Rasha H. El-Mahdy And Abeer A. El-Fallal,

ABSTRACT
Objective. This Study Evaluated The Bond Strength Of Resin-modified Glass Ionomer Cement (RMGIC) To Microbiologically Produced Caries-affected Dentine Treated With Chlorhexidine. Methods. 101 Human Molars; 80 For Micro-shear Bond Strength (�SBS) Evaluation And 21 To Detect The Dentine Morphology. Caries Affected Dentine Were Produced By Placing Dentine Discs In A Cariogenic Solution That Contains Streptococcus Mutans And Incubating Them For 7 Days At 37� C. Specimens Were Divided Into Eight Groups (n=10); Group A; Sound Dentine (SD), Group B; Caries Affected Dentine (CAD), Group C; 30 CAD Specimens Subdivided Into C1, C2 & C3 (0.5%, 0.05% Or 0.02%) Of CHX Incorporated Into Polyacrylic Acid Conditioner, Group D ; 30 CAD Specimens Subdivided Into D1, D2 & D3 (0.5 % , 0.05% Or 0.02%) Of CHX Solution Used After Acid Conditioning. RMGIC Micro-cylinders Were Built On The Dentine Discs. After 24 H, �SBS Was Evaluated By Applying A Shearing Load To The Micro-cylinder, By A Testing Machine At A Crosshead Speed Of 0.5 Mm/min.

Results: The Results Showed A High Statistically Significant Difference Of Sound Dentine With All Groups Except Group D3 (p=0.069). Mean Shear Stress Was Highest In Sound Dentine (16.64 �3.83) Followed By Group D3 (13.97�1.78). All Groups Revealed Higher Percent Of RMGIC Cohesive Failures. Surface Morphological Examination Of Conditioned CAD Showed That The Experimental Conditioners Removed The Smear Layer. Conclusion: CHX Application; Either Solely Or Coupled With Acid Conditioner Caused No Antagonistic Effects On RMGI Bond Strength To Caries-affected Dentine.