تأثير تقنية التخريش على قوة الارتباط العاجي لنظامين مختلفين من المواد الرابطة للراتنج المركب (دراسة مخبرية)

Aim: The aim of this study is to compare the the effect of etching techniaue on bonding strength to dentin of two composite bonding systems . Materials and Methods: 40 freshly human upper premolars extracted due to orthodontic reasons , non carious, unrestored. Then they divided into two groups (A,B). After exposing the dentin of the occlusal surface, we applied the total etch bonding system (Excite f) to group A and self etch bonding system (tetric N-bond self etch) to group B then teeth were applied in acrylic resin blocks. Bonding strength were determind using shear bond strength test. Results were evaluated statistically using T student test (P