Salivary pellicle composition and multispecies biofilm developed on titanium nitrided by cold plasma.
OBJECTIVE
The aim of this study was to evaluate the composition of the salivary pellicle (SP) and multispecies biofilm developed on titanium nitrided by cold plasma.


METHODS
Titanium discs were allocated into a control group (Ti) and an experimental group (TiN - titanium-nitrided by cold plasma). The disc surface topography was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The chemical composition of the disc surface was determined by X-ray photoelectron spectroscopy (XPS). Stimulated, clarified, and filtered saliva was used to form pellicles on the discs. Proteome analysis of the adsorbed SP proteins was performed by liquid chromatography-mass spectrometry (LC-MS). The surface free energy (SFE) was evaluated before and after SP formation. A multispecies biofilm composed of Actinomyces naeslundii, Streptococcus oralis, Streptococcus mutans, Fusobacterium nucleatum, Veillonella dispar, and Candida albicans was developed on the SP-coated discs. Viable microorganism counts were determined. The biomass and average thickness of biofilms were analyzed by confocal laser-scanning microscopy (CLSM) with COMSTAT software. The biofilm organization was visualized by SEM.


RESULTS
The surface topography was similar in both groups. The SFE of the TiN group did not differ from that of the Ti group (p>0.05), although the adsorption of pellicle proteins increased the SFE in both pellicle-coated groups (p<0.001). Different proteins were identified on the Ti and TiN surfaces. The amount of biofilm was similar for both groups (p=0.416), but the counts of F. nucleatum and S. oralis were higher in the TiN group (p<0.001). Similar biofilms were characterized by the COMSTAT data, CLSM images, and SEM images.


CONCLUSIONS
The titanium nitrided by cold plasma exhibited differences in SP composition and multispecies microbial biofilm population compared to the control titanium surface.
Piracicaba Dental School, University of Campinas, Department of Periodontology and Prosthodontics, Limeira Avenue, 901, Piracicaba, São Paulo, Brazil.
I M G
IM
Cavalcanti
Piracicaba Dental School, University of Campinas, Department of Periodontology and Prosthodontics, Limeira Avenue, 901, Piracicaba, São Paulo, Brazil.
A P
AP
Ricomini Filho
Piracicaba Dental School, University of Campinas, Department of Periodontology and Prosthodontics, Limeira Avenue, 901, Piracicaba, São Paulo, Brazil.
S C
SC
Lucena-Ferreira
Piracicaba Dental School, University of Campinas, Department of Periodontology and Prosthodontics, Limeira Avenue, 901, Piracicaba, São Paulo, Brazil.
W J
WJ
da Silva
Mass Spectrometry Laboratory, Brazilian Biosciences National Laboratory (LNBio), Giuseppe Máximo Scolfaro Street, 10.000 Campinas, São Paulo, Brazil.
A F
AF
Paes Leme
Piracicaba Dental School, University of Campinas, Department of Periodontology and Prosthodontics, Limeira Avenue, 901, Piracicaba, São Paulo, Brazil.
P M
PM
Senna
Piracicaba Dental School, University of Campinas, Department of Periodontology and Prosthodontics, Limeira Avenue, 901, Piracicaba, São Paulo, Brazil. Electronic address: altcury@fop.unicamp.br.
A A
AA
Del Bel Cury
D018441:Biofilms; D044622:Dental Pellicle / Q000737:chemistry* / Q000382:microbiology*; D018625:Microscopy, Atomic Force; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D056951:Photoelectron Spectroscopy; D058626:Plasma Gases; D012471:Salivary Proteins and Peptides / Q000737:chemistry; D012984:Software; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
D058626:Plasma Gases; D012471:Salivary Proteins and Peptides; D014025:Titanium
Biofilm; Proteome; Saliva; Surface; Titanium