• Kanchana Kanchanatawewat
• Boonlert Kukiattrakoon

Objective  The purpose of this study was to evaluate the shear bond strength (SBS) of high leucite content porcelain (EMP) bonded to aluminous porcelain (AP) using resin cement under different surface treatments.

Materials and methods  300 EMP discs, having a diameter of 5.5 mm and a width of 1 mm, were divided into 5 types, (60 discs/type); Type A no surface treatment to be served as a control group; Type B polished with Sic paper; Type C ground with a coarse diamond bur; Type D etched with HF acid for 5 min and Type E etched with APF gel for 10 min. 300 AP discs having a diameter of 15 mm. and a width of 1.5 mm were divided into 6 groups (50 discs/group). Group 1 as type A; Group 2 as type B; Group 3 as type C; Group 4 sandblasted with alumina particles for 20 s; Group 5 as type D and Group 6 as type E. AP discs were embedded in clear acrylic resin blocks and then bonded to EMP discs using resin cement under a load of 200 grams. All samples were subjected to SBS evaluation using a univerasal testing machine having a crosshead speed 0.2 mm/mm ANOVA and Tukey’s statistical analyses were performed on the data.

Results  Bonding of AP to EMP having both surface treatments (Group 3-6A, 3-6C, 3-6D and 3-6E) gave significantly (p<0.05) higher SBS ranging from 25.2+3.8 to 30.2+2.0 MPa. There was no significant difference (p>0.05) among AP bonded to EMP (Group 1-2 to Type A-E and Group 5-6 to Type A-B).

Conclusion  Overall results indicate that the surface treatments of either AP or EMP has a significant (p<0.05) effect on the SBS of all tested materials. Consequently, EMP is recommended for repairing of porcelain-fractured restorations.

(CU Dent J 2001;24:175-86)