Effects of Sandblasting and Er:YAG Laser Irradiation for Surface Treatment of Nickel-Chromium Alloy on Its Shear Bond Strength to Composite Resin

Seyedeh Maryam  Tavangar; Yousef  Jahandideh; Kazem  Saber; Reza Tayefeh  Davalloo; Farideh  Darabi; Dina  Maleki; Reza  Ahmadi

doi:10.18502/fid.v23i19.21770

Seyedeh Maryam Tavangar Department of Operative Dentistry, School of Dentistry, Guilan University of Medical Sciences, Rasht, Iran
Yousef Jahandideh Department of Prosthodontics, School of Dentistry, Guilan University of Medical Sciences, Rasht, Iran
Kazem Saber Private Practice, Rasht, Iran
Reza Tayefeh Davalloo Department of Operative Dentistry, School of Dentistry, Guilan University of Medical Sciences, Rasht, Iran
Farideh Darabi Department of Operative Dentistry, School of Dentistry, Guilan University of Medical Sciences, Rasht, Iran
Dina Maleki Dental Sciences Research Center, School of Dentistry, Guilan University of Medical Sciences, Rasht, Iran
Reza Ahmadi Department of Operative Dentistry, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran

DOI: https://doi.org/10.18502/fid.v23i19.21770

Keywords: Composite Resins; Dental Porcelain; Lasers; Shear Strength

Abstract

Objectives: This study evaluated the effect of different surface treatments of nickel-chromium (Ni-Cr) alloy on its shear bond strength (SBS) to composite resin.

Materials and Methods: In this in vitro study, 45 Ni-Cr discs were fabricated and randomly assigned to three groups (n=15). Group 1 underwent sandblasting with 50µm aluminum oxide (Al₂O₃) particles at 60psi for 10 seconds. Group 2 was treated with Er:YAG laser (500mJ, 10Hz, 5W for 20 seconds). Group 3 received sandblasting followed by Er:YAG laser irradiation. A universal adhesive containing 10-MDP monomer was applied on all specimens, and composite resin cylinders were bonded to the treated metal surfaces. After 10,000 thermal cycles (5°C/55°C), SBS was measured using a universal testing machine. Failure modes were examined under a stereomicroscope at ×40 magnification. Data were analyzed by one-way ANOVA (alpha=0.05).

Results: Significant differences in the mean SBS was observed among the groups (P<0.001). Sandblasting + Er:YAG laser exhibited the highest mean SBS (14.32±1.83MPa), which was significantly greater than that of the sandblasting group (12.73±1.62MPa; P=0.036) and the Er:YAG laser group (6.85±1.60MPa; P<0.001). The sandblasting group also showed significantly higher SBS than the Er:YAG laser group (P<0.001). No significant difference was found in the mode of failure among the groups (P=0.999), with mixed failure predominating in all groups.

Conclusion: Surface treatment of Ni-Cr alloy by a combination of sandblasting with Al₂O₃ particles and Er:YAG laser irradiation produced significantly higher SBS to composite resin than either sandblasting or Er:YAG laser treatment alone.