Impact of gastric acidic challenge on surface topography and optical properties of monolithic zirconia

Taiseer A Sulaiman; Aous A Abdulmajeed; Khalil Shahramian; Leena Hupa; Terrence E Donovan; Pekka Vallittu; Timo O Närhi

doi:10.1016/j.dental.2015.09.010

Impact of gastric acidic challenge on surface topography and optical properties of monolithic zirconia

Dent Mater. 2015 Dec;31(12):1445-52. doi: 10.1016/j.dental.2015.09.010. Epub 2015 Oct 20.

Authors

Taiseer A Sulaiman¹, Aous A Abdulmajeed², Khalil Shahramian², Leena Hupa³, Terrence E Donovan⁴, Pekka Vallittu⁵, Timo O Närhi⁶

Affiliations

¹ Department of Prosthetic Dentistry, Institute of Dentistry, University of Turku, Turku, Finland; Turku Clinical Biomaterials Centre (TCBC), University of Turku and City of Turku, Finland; Department of Operative Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, NC, USA. Electronic address: dr.taiseer@gmail.com.
² Department of Prosthetic Dentistry, Institute of Dentistry, University of Turku, Turku, Finland; Turku Clinical Biomaterials Centre (TCBC), University of Turku and City of Turku, Finland.
³ Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, 20500 Turku, Finland.
⁴ Department of Operative Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, NC, USA.
⁵ Turku Clinical Biomaterials Centre (TCBC), University of Turku and City of Turku, Finland; Department of Biomaterials Science, Institute of Dentistry, University of Turku, and Division of Welfare, Turku, Finland.
⁶ Department of Prosthetic Dentistry, Institute of Dentistry, University of Turku, Turku, Finland; Turku Clinical Biomaterials Centre (TCBC), University of Turku and City of Turku, Finland; Clinic of Oral Diseases, Turku University Central Hospital, Turku, Finland.

PMID: 26494266
DOI: 10.1016/j.dental.2015.09.010

Abstract

Objective: To evaluate the surface topography and optical properties of monolithic zirconia after immersion in simulated gastric acid.

Materials and methods: Four partially stabilized (PSZ) and one fully stabilized (FSZ) zirconia materials were selected for the study: Prettau (PRT, Zirkonzahn), Zenostar (ZEN, Ivoclar), Bruxzir (BRX, Glidewell), Katana (KAT, Noritake) and FSZ Prettau Anterior (PRTA, Zirkonzahn). IPS e.max (Ivoclar) was used as a control. The specimens (10×10×1.2mm, n=5 per material) were cut, sintered, polished and cleaned before immersed in 5ml of simulated gastric acid solution (Hydrochloric acid (HCl) 0.06M, 0.113% solution in deionized distal water, pH 1.2) for 96h in a 37°C incubator. Specimens were weighed and examined for morphological changes under scanning electron microscope (SEM) coupled with energy dispersive X-ray spectroscopy (EDX). Surface roughness was evaluated by a confocal microscope. Surface gloss and translucency parameter (TP) values were determined by a reflection spectrophotometer before and after acid immersion. The data was analyzed by one-way ANOVA followed by Tukey's HSD post hoc test (p<0.05).

Results: PRTA displayed the most weight loss (1.40%) among the zirconia specimens. IPS e.max showed about three times more weight loss (3.05%) than zirconia specimens as an average. SEM examination indicated areas of degradation, bead-like shapes and smoothening of the polishing scratches after acid immersion. EDX displayed ion interactions and possible ion leaching from all specimens. Sa and Sq values for PRTA, ZEN and IPS e.max were significantly lower (p<0.05) after acid immersion. TP values increased significantly for PRT, ZEN and IPS e.max (p<0.05), while the surface gloss of ZEN, PRTA and IPS e.max increased (p<0.05).

Significance: Monolithic zirconia materials show some surface alterations in an acidic environment with minimum effect on their optical properties. Whether a smoother surface is in fact a sign of true corrosion resistance or is purely the result of an evenly progressive corrosive process is yet to be confirmed by further research.

Keywords: Corrosion resistance; Monolithic zirconia; Optical properties; Simulated gastric acid; Surface topography.

MeSH terms

Corrosion
Dental Materials / chemistry*
Hydrochloric Acid / chemistry*
Materials Testing
Microscopy, Confocal
Microscopy, Electron, Scanning
Optics and Photonics
Spectrometry, X-Ray Emission
Surface Properties
Zirconium / chemistry*

Substances

Dental Materials
Zirconium
Hydrochloric Acid