Evaluation of the shear bond strength of the intraoral porcelain repair system with different surface treatments : in vitro study

Abstract EN

Problem : When clinical fracture of the ceramic veneer on ceramometal can be repaired, the need for remake can be eliminated.

Purpose : Investigated the effects of different surface treatments on the shear bond strength of an intraoral porcelain repair system.

Materials and methods : 120 Specimens were prepared in form of metal disks (8mm in diameter, 4mm height) and randomly divided into three surface groups : metal (A), porcelain (B) and metal Porcelain combined surface (C).

Vivadent ceramic repair system was tested.

Each group was divided into four subgroups according to the types of surface treatments applied all the samples were treated with Air –abrasion with Al2O3 (50μm) 20 sec.

then Subgroup No.1 etch.

With 37 % phosphoric acid.

for 15 sec, Subgroup No.2 etch.

With 37 % phosphoricacid.

for 4 min, Subgroup No.3 etch.

With 37 % phosphoric acid.

for 15 sec.

+ silane and Subgroup No.4 etch.

with 37% phosphoric acid for 4min + silane.

Resin were applied to all the samples.

Shear bond strength of 10 specimens for each subgroup were determined with a Zwick universal testing machine after storing in distilled water at 370C for 7 days, during this period thermocycling at 50C –550C for 300 cycles with 30 sec.

dwell.

The data were analyzed with analysis of variance and Duncan’s multiple range test.

Results : There was no significant difference (P > 0.05) in the bond strength among the different subgroups for metal groups.

On the porcelain and metal porcelain combined surface groups, there was a significant difference (P < 0.01) among the different subgroups for each group with best bond obtained with the application of silane agent for both groups.

Conclusions : Silane had no influence on bond strength of composite resin to metal surface with the best results obtained when the fracture was limited into porcelain and the use of silane agent dramatically enhance bond strength of composite resin to etched porcelain for 15 sec.

in both porcelain group and metal porcelain combined surface group, but extending the etching time to 4 min.

caused a decrease in the shear bond strength in porcelain group only.