# Effect of different surface treatments on the bond strength of zirconia to resin cement. An in vitro study

## TL;DR

This study tests new surface treatments for zirconia to improve its bond with resin cement, finding that some treatments significantly increase bond strength.

## Contribution

The study introduces and evaluates novel zirconia surface treatments that significantly enhance bond strength with resin cement.

## Key findings

- Zircos-E etching, APA+Zircos-E, and Biomic LiSi Connect significantly increased bond strength compared to the control.
- Biomic LiSi Connect showed the highest mean shear bond strength among all tested treatments.
- Failure mode analysis showed no significant differences among the groups.

## Abstract

Achieving a durable and stable bond between zirconium dioxide (zirconia) and resin cement remains a significant clinical challenge. This study aimed to investigate the effects of two novel zirconia surface treatments on the shear bond strength (SBS) between zirconia and resin cement following thermocycling.

Seventy-five CAD/CAM zirconia specimens (8 × 10 × 8 mm) were fabricated and randomly assigned to five groups (n = 15): control (no treatment); air particle abrasion (APA); Zircos-E etching; APA+Zircos-E; Biomic LiSi Connect. All specimens were bonded using a zirconia primer, adhesive system, and dual-cure resin cement, except for Biomic LiSi Connect, which did not receive the zirconia primer treatment. Subsequently, all specimens underwent thermo-cycling. SBS was measured, and failure modes were classified. Statistical analysis revealed significant differences in SBS among the groups (p < 0.001).

Zircos-E etching, APA+Zircos-E and Biomic LiSi Connect exhibited significantly higher bond strength than the control, with Biomic LiSi Connect demonstrating the highest mean SBS (p < 0.001). Failure mode analysis showed no statistically significant differences among groups. Both Zircos-E and Biomic LiSi Connect significantly enhanced the bond strength.