Effect of silica coating and laser treatment on the flexural strength, surface characteristics, and bond strength of a dental zirconia. (27th January 2021)

• Record Type: Journal Article
• Authors: da Silva, Beatriz Togoro Ferreira; Trevelin, Livia Tosi; Schroeter, Ananda Carolina; Willers, Amanda Endres; Cesar, Paulo Francisco; Matos, Adriana Bona
• Is Part Of: European journal of oral sciences. Volume 129:Number 1(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-01-27
• Subjects: Er:YAG laser -- mechanical properties -- surface characteristics -- zirconium; Dentistry -- Periodicals; Oral medicine -- Periodicals; 617.6005
• DOI: 10.1111/eos.12754
• Languages: English
• ISSNs: 0909-8836

Abstract

Abstract: This study investigated the effect of irradiation with an erbium‐doped yttrium aluminium garnet (Er:YAG) laser and coating with silica on the surface characteristics, bond strength, and flexural strength of dental zirconia. Three hundred and forty‐three standard zirconia specimens were created, and 49 were assigned to each of seven surface treatment groups: (i) no treatment; Er:YAG laser (80 mJ/2 Hz) with pulse widths of 50 μs (ii), 100 μs (iii), 300 μs (iv), or 600 μs (v); or tribochemical silica coating at the partially sintered stage (vi) or after sintering was complete (vii). All specimens were sintered after the surface treatments, except for the group in which specimens were sintered before treatment. The study outcomes were roughness, surface loss, microshear bond strength (μSBS), and biaxial flexural strength (BFS). Mean roughness and surface loss values were significantly higher in specimens from irradiated groups than in those from silica‐coated groups. Regarding μSBS, after aging, specimens from all experimental groups presented very low and similar μSBS values, irrespective of the surface treatment. Silica coating after sintering yielded the highest BFS (1149.5 ± 167.6 MPa), while coating partially sintered specimens with silica resulted a BFS (826.9 ± 60.9 MPa) similar to that of the untreated control group (794.9 ± 101.7 MPa). Laser treatments, irrespective of pulse width used, significantly decreased the BFS. In the group treated with laser at 300 μs pulse width, specimens exhibited the lowest BFS value (514.1 ± 71.5 MPa). Adhesion to zirconia was not stable after aging, regardless of the surface treatment implemented.