Surface roughened zirconia: towards hydrothermal stability

Abstract

Surface roughness is needed in several yttria-stabilized zirconia components used in restorative dentistry for osseointegration or adhesion purposes. This can be achieved by different treatments, which may also modify the microstructure of the surface. Among them, sandblasting and chemical etching are widely used, but their effect on hydrothermal aging of zirconia is not fully understood. In the present work, the zirconia long-term stability of rough surfaces prepared by these techniques is analyzed and a method is proposed for preventing hydrothermal aging while maintaining the original surface appearance and mechanical properties. The method involves pressure infiltration of a Cerium salt solution on the roughened surfaces followed by a thermal treatment. The solution, trapped by surface defects and small pores, is decomposed during thermal treatment into Cerium oxide, which is diffused at high temperature, obtaining Ce co-doping in the near-surface region.In addition, the microstructural changes induced in the near-surface by sandblasting or chemical etching are removed by the thermal treatment together with surface defects. No color modification was observed and the final roughness parameters were in the range of existing implants of proved good osseointegration. The aging resistance of Ce co-doped materials was strongly enhanced, showing the absence of aging after artificial degradation, increasing in this way the surface mechanical integrity.The proposed treatment is easily applicable to the current manufacturing procedures of zirconia dental posts, abutments, crowns and dentures, representing a solution to hydrothermal aging in these and other biomedical applications.

Biological and osseointegration capabilities of hierarchically (meso-/micro-/nano-scale) roughened zirconia

“…39,52 There has been a considerable interest and effort in improving zirconia surfaces, particularly the development of surface roughening techniques. Physical, [53][54][55] chemical, [54][55][56] and thermochemical 57 modifications of zirconia surfaces successfully improved cellular response and function. However, roughness parameters reported for zirconia implants are generally lower than those for titanium implants.…”

Bonding Strength of Ceromer with Direct Laser Sintered, Ni-Cr-Based, and ZrO2 Metal Infrastructures After Er:YAG, Nd:YAG, and Ho:YAG Laser Surface Treatments—A Comparative In Vitro Study

“…During the impact, local surface plastic deformation and subsurface cracks may be generated. 29 In recent years, it seems logical to investigate the effect of laser irradiation on metal surfaces of dental prosthetics to modify surface morphology even if today study results are still controversial. 14,20,[30][31][32][33] Lin et al 14 investigate whether or not erbium: yttriumaluminum-garnet (Er:YAG) lasers could improve the bonding property of zirconia ceramics to resin cement.…”

Artificial Aging of Zirconium Dioxide: An Evaluation of Current Knowledge and Clinical Relevance

“…In addition, alumina traces (Al 2 O 3 ) [38,46], silica and/or ceria (CeO 2 ) [39] could be added to the composition to improve the resistance of zirconia against LTD. In particular, ceria as an oxide demonstrates favourable stabilization effect as it has concentration of about 12 mol% and makes zirconia non-transformable [47,48].…”