Mechanical reliability of dental grade zirconia after laser patterning. (October 2018)

• Record Type: Journal Article
• Authors: Roitero, E.; Anglada, M.; Mücklich, F.; Jiménez-Piqué, E.
• Is Part Of: Journal of the mechanical behavior of biomedical materials. Volume 86(2018)
• Page Start: 257
• Page End: 263
• Publication Date: 2018-10
• Subjects: Laser treatment -- 3Y-TZP -- Direct laser interference patterning -- Mechanical properties; Biomedical materials -- Periodicals; Biomedical materials -- Mechanical properties -- Periodicals; Biomedical materials; Biomedical materials -- Mechanical properties; Periodicals; Electronic journals; 610.28
• DOI: 10.1016/j.jmbbm.2018.06.039
• Languages: English
• ISSNs: 1751-6161

Abstract

Abstract: The aim of this work is to test the mechanical properties of dental zirconia surfaces patterned with Nd:YAG laser interference ( λ = 532 nm and 10 ns pulse). The laser treatment produces an alteration of the topography, engraving a periodic striped pattern. Laser-material interaction results mainly in thermal effects producing microcracking, phase transformation and texturization. The role of such microstructural modifications and collateral damage on the integrity and mechanical performances has been assessed. Laser patterned discs of zirconia doped with 3% mol yttria (3Y-TZP) have been tested before and after a thermal treatment to anneal residual stresses and revert phase transformation. Both groups of samples behave in a similar manner, excluding residual stresses and phase transformation from the origin of properties modification. Result show that laser patterning induces a minor decrease in mechanical properties and surface integrity of 3Y-TZP surfaces. The biaxial strength decreases as a consequence of the damage induced by laser patterning. Fractographic observations identify preexisting defects enlarged by local laser interaction as the fracture origins. The Hardness and Young modulus of treated surfaces tested with nanoindentation also decrease slightly after laser treatment and this may be attributed to laser-induced microcracking. Graphical abstract: fx1 Highlights: Laser patterning on dental zirconia reduces strength but increases Weibull modulus. Changes in strength are due to interaction of laser with natural defects. Surfaces treated with laser show lower hardness and scratch resistance.