Surface Activation of Titanium Dental Implants by Using UVC-LED Irradiation

Abstract

Organic contaminants significantly limit the bioactivity of titanium implants, resulting in the degradation known as the ageing of titanium. To reactivate the surfaces, they can be photofunctionalized, i.e., irradiated with C-range ultraviolet (UVC) light. This descriptive in vitro study compares the effectiveness of novel light-emitting diode (LED) technology to remove contaminant hydrocarbons from three different commercially available titanium dental implants: THD, TiUnite, and SLA. The surface topography and morphology were characterized by scanning electron microscopy (SEM). The chemical compositions were analyzed by X-ray photoelectron spectroscopy (XPS), before and after the lighting treatment, by a pair of closely placed UVC (λ = 278 nm) and LED devices for 24 h. SEM analysis showed morphological differences at the macro- and micro-scopic level. XPS analysis showed a remarkable reduction in the carbon contents after the UVC treatment: from 25.6 to 19.5 C at. % (carbon atomic concentration) in the THD; from 30.2 to 20.2 C at. % in the TiUnite; from 26.1 to 19.2 C at. % in the SLA surface. Simultaneously, the concentration of oxygen and titanium increased. Therefore, LED-based UVC irradiation decontaminated titanium surfaces and improved the chemical features of them, regardless of the kind of surface.

Response of Human Gingival Fibroblasts and Porphyromonas gingivalis to UVC-Activated Titanium Surfaces

“…For this reason, UVC pretreatment was applied in this study to optimize the bioactivity and antimicrobial activity of different Ti surfaces. After UVC pretreatment, both smooth and nano-Ti surfaces achieved a static WCA at 0° ( Table 2 ) as evidence of a super-hydrophilic transition ( Figure 1 G,H) without significant changes in surface topography or roughness, which was consistent with the previous research [ 33 ]. This phenomenon was explained by the removal of carbohydrate contaminants and the production of hydrophilic chemicals [ 25 ].…”

The response of bioactive titanium surfaces with different structure to UVC-irradiation to eliminate the negative effect on biological properties during aging time

“…Previous studies have confirmed that the tendency of organic components adsorption and decrease in hydrophilicity also occurred on surfaces of titanium alloys during biological aging [11,13]. Additionally, it has been demonstrated that the effect of UV-irradiation could regenerate the biological properties of titanium alloys as well [56,57]. Given that the alloy elements could contribute to enhancing photocatalytic performance of titanium alloys [58], the mechanism of improving biological performance under UV-irradiation could be different from that of pure titanium and remains to be further studied.…”

Peculiar opportunities given by XPS spectroscopy for the clinician

“…Several papers [112,113] have underlined the different instrumentation and methodology advances that have enhanced the ability to study organic and biological systems through XPS spectroscopy. Among the biological systems and biomaterials which can be investigated through XPS spectroscopy, we can quote bacteria [114,115], Human cells [116,117], dental implants [118][119][120], intraocular lens [121,122] or physiological as well as pathological calcifications such as (not only human ones) [123][124][125], teeth [126][127][128], vascular calcifications [13,129] or kidney stones [130].…”