title: Formation and photocatalytic decomposition of a pellicle on anatase surfaces.
abstract: The acquired dental pellicle plays a critical role in the adhesion and detachment of dental plaque bacteria. It has been reported that titanium dioxide biomaterials decompose single-protein films by photocatalysis. However, it is not known whether this can also be achieved with complex structured pellicle films. This in vitro study investigated in real-time the formation and photocatalytic decomposition of human pellicle at anatase-saliva interfaces. Nanostructured polycrystalline anatase layers were deposited on titanium-coated quartz crystals by magnetron-sputtering, serving as a model for titanium implant surfaces. The quartz crystals were used as acoustic sensors in a quartz-crystal microbalance (QCM) system with dissipation. In situ UV irradiation of pellicle-covered anatase caused a statistically significant decrease of the adsorbed salivary mass. In contrast, photocatalytic decomposition of pellicle could not be observed on reference titanium surfaces. Wettability characterization revealed superhydrophilicity of anatase upon UV irradiation, whereas titanium was unaffected. XPS measurements provide further information concerning the decomposition of the salivary films. The results suggest that the photocatalytic activity of polycrystalline anatase-modified biomaterial surfaces is able to decompose complex structured macromolecular pellicle films. Therefore, this study opens the way to surface modifications supporting therapeutic approaches of biofilm removal.
authors: University Hospital Tuebingen, Department of Prosthetic Dentistry, Section Medical Materials and Technology, Osianderstrasse 2-8, Tuebingen, Germany. frank.rupp@med.uni-tuebingen.de
authors: F
authors: F
authors: Rupp
authors: M
authors: M
authors: Haupt
authors: M
authors: M
authors: Eichler
authors: C
authors: C
authors: Doering
authors: H
authors: H
authors: Klostermann
authors: L
authors: L
authors: Scheideler
authors: S
authors: S
authors: Lachmann
authors: C
authors: C
authors: Oehr
authors: H P
authors: HP
authors: Wendel
authors: E
authors: E
authors: Decker
authors: J
authors: J
authors: Geis-Gerstorfer
authors: C
authors: C
authors: von Ohle
mesh_terms: D000327:Adsorption; D000704:Analysis of Variance; D002384:Catalysis; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D044622:Dental Pellicle / Q000378:metabolism / Q000528:radiation effects*; D006801:Humans; D008422:Materials Testing; D053758:Nanoparticles; D056951:Photoelectron Spectroscopy; D058525:Quartz Crystal Microbalance Techniques; D012471:Salivary Proteins and Peptides / Q000378:metabolism*; D018709:Statistics, Nonparametric; D014025:Titanium; D014466:Ultraviolet Rays; D017155:Wettability
chemical_list: D020099:Coated Materials, Biocompatible; D012471:Salivary Proteins and Peptides; C009495:titanium dioxide; D014025:Titanium