EFFECT OF DIFFERENT SALIVA DECONTAMINATION PROCEDURES ON THE SHEAR BOND STRENGTH OF A UNIVERSAL EIGHTH GENERATION ADHESIVE SYSTEM TO DENTIN AFTER POLYMERIZATION - AN IN VITRO STUDY

Aim: To evaluate and compare the effect of saliva decontamination procedure on the shear bond strength of a Universal eighth generation adhesive system to dentin after polymerization. Materials & Method: Forty extracted non-carious premolars were mounted on a acrylic block and their occlusal surfaces were grounded flat to exposed the middle depth dentin. The teeth were then randomly divided into five Groups: Group A(control), Group B(Bonding, Saliva, Air-dried), Group C(Bonding, Saliva, Air-dried, Rinse), Group D(Bonding, Saliva, Air-dried, Re-bonding) & Group E (Bonding, Saliva, Air-dried, Rinse, Re-bonding). A teflon tube of 2x3 mm dimension was used to pack composite on the treated dentin surface and light cured for 40s. Shear Bond strength was then measured using instron testing machine at a crosshead speed of 1mm/min. Data were statistically analysed using ONE WAY-ANOVA and TUKEYS test. Result: It was observed that, the highest mean shear bond strength was found in Group D(Bonding, Saliva, Air-dried, Re-bonding) & Group E(Bonding, Saliva, Air-dried, Rinse, Re-bonding) with a mean value of 23.87 each. The least mean value was seen in Group C(Bonding, Saliva, Air-dried, Rinse), 13.25. When an intergroup comparision was made, statistically significant difference was seen between the various groups except Group A(control)-Group D(Bonding, Saliva, Air-dried, Re-bonding)-Group E(Bonding, Saliva, Air-dried, Rinse, Re-bonding) and Group B(Bonding, Saliva, Air-dried)-Group C(Bonding, Saliva, Air-dried, Rinse). Conclusion: Salivary contamination significantly decreases the bond strength of the adhesive to dentin after polymerization. Rinsing and Air-drying of the cured contaminated dentin surface was not sufficient to restore the shear bond strength. However reapplication of adhesive system after rinsing and air-drying of the cured contaminated dentin surface fully restored the bond strength.