This article has been retracted at the request of the Editor-in-Chief, because the authors plagiarized a previously published paper that had appeared in: Int J Oral Maxillofac Implants, 26 (2011) 101–107. This article presented the same table and figures as the original study, and changed 2 of the tables to figures. This article reflects severe abuse of the scientific publishing system, and has therefore been retracted.
Bacterial Adhesion ; Colon ; Humans ; Titanium

Dental plaque is structurally a kind of biofilm which contains a variety of micro-organisms. The interreaction of oral micro-organisms may affect the nature, forms, and toxicity of the dental plaque biofilm, as well as the localization and field planting of bacteria inside the biofilm. The signal transduction existed between the bacterium has an important effect on the formation and virulence of bacterial biofilm. This reviewing paper focuses on the latest research progress of human oral microbial community and dental plaque biofilm.
Bacteria ; Bacterial Adhesion ; Biofilms ; Dental Plaque ; Humans

As an important protein structure on the surface of bacteria, type Ⅳ pili (TFP) is the sensing and moving organ of bacteria. It plays a variety of roles in bacterial physiology, cell adhesion, host cell invasion, DNA uptake, protein secretion, biofilm formation, cell movement and electron transmission. With the rapid development of research methods, technical equipment and pili visualization tools, increasing number of studies have revealed various functions of pili in cellular activities, which greatly facilitated the microbial single cell research. This review focuses on the pili visualization method and its application in the functional research of TFP, providing ideas for the research and application of TFP in biology, medicine and ecology.
Fimbriae, Bacterial/metabolism* ; Bacterial Proteins/genetics* ; Bacterial Physiological Phenomena ; Bacterial Adhesion/physiology*

OBJECTIVE: To evaluate the process characterization of graphene oxide loaded on pure titanium surface and effect on the biological properties of Staphylococcus aureus and osteoblasts. METHODS: Graphene oxide at four concentrations (20, 50, 80, and 100 µg·mL⁻¹) was loaded on the pure titanium surface via electroplating, and the morphology, properties, and hydrophilic properties were measured with a field emission scanning electron microscope, micro Raman spectrometer, and contact angle tester, respectively. In addition, Staphylococcus aureus and osteoblasts were used as models and cultured with pure titanium-graphene oxide. Then, field-emission scanning electron microscopy and laser confocal microscopy were utilized to observe the changes in the amount of bacteria and osteoblast morphology and structure, respectively. RESULTS: Graphene oxide at the four concentrations was successfully loaded on pure titanium surface via electroplating. It improved the hydrophilic properties of pure titanium surface, which benefitted the adhesion and growth of Staphylococcus aureus and changed the morphology and structure of the osteoblasts. CONCLUSIONS The pure titanium-graphene oxide composite has no antibacterial properties and has good biocompatibility.
Bacterial Adhesion ; Cell Adhesion ; Graphite ; Microscopy, Electron, Scanning ; Osteoblasts ; Oxides ; Surface Properties ; Titanium

PURPOSE: The aim of this study was to compare the number of live and dead bacteria attached to, or within, the stratified squamous epithelium lining the tissue side of the gingival sulcus. MATERIALS AND METHODS: A total of 50 patients was examined and classified into healthy or diseased sites according to inflammatory status of the gingival tissue. The surface of stratified squamous epithelium was removed by gentle scraping of the gingival sulcus with curettes. The cells were processed in the laboratory by density-gradient centrifugation to separate the epithelial cells from the loose bacteria and debris. The LIVE/DEAD(R) BacLight(TM) Bacterial Viability Kit was applied and the specimens were observed by an epifluorescent microscope and the number of bacteria was counted. RESULTS: Live and dead bacteria were stained to green and red, irrespectively. Generally, the number of total bacteria in the diseased sites was significantly higher than in the healthy sites. The mean number of detected bacteria in the diseased sites was 58.6+/-36.0 (red bacteria 10.4+/-9.2 / green bacteria 48.2+/-30.5), while it was 1.5+/-1.7 in the healthy sites (red bacteria 0.1+/-0.3 / green bacteria 1.4+/-1.5). The percentage of red bacteria was 17.5+/-11.2% in the diseased sites and 2.0+/-5.8% in the healthy sites. CONCLUSION: The total number of bacteria in the diseased sites was significantly higher than that of the healthy sites. The ratio and the number of red bacteria were also significantly higher in the diseased sites.
Bacteria ; Bacterial Adhesion ; Centrifugation ; Epithelial Cells ; Epithelium ; Humans ; Microbial Viability

OBJECTIVETo study the effect of concentrations of glucose on the initial adherence of Streptococcus mutans (S. mutans) to saliva-coated hydroxyapatite (SHA), and to compare the initial adherence of S. mutans from caries-active group with that of S. mutans from caries-free group.

METHODSEach 10 clinical isolates of S. mutans from caries-active and caries-free subjects were used in this study. And S. mutans UA159 was also included in this experiment. SHA was used to simulate tooth surface in oral cavity. S. mutans clinical isolates and strain UA159 were cultured in TPY liquid medium containing 3H-TdR in the same radioactive concentration and glucose in 0.2%, 1.0%, 5.0% concentration. Then grown cells were harvested to produce a suspension. SHA and radiolabelled bacterial suspension (A550(nm) = 0.52) were mixed for 90 minutes, samples were assayed by using liquid scintillation counter, and binding abilities of strains were evaluated by the count per minute (CPM).

RESULTSThe initial adherence ability of S. mutans from caries-active group was higher than that of S. mutans from caries-free group (P < 0.05). And the initial adherence ability of S. mutans cultured in different concentration of glucose was also significantly different (P < 0.05), 5.0% glucose group had the highest adherence ability, and 0.2% glucose group had the lowest adherenceability.

CONCLUSION(1)Difference of the initial adherence of S. mutans might relate to difference of carious experiences; (2) Glucose may play an important role in S. mutans initial adherence, to some extent, S. mutans cultured in the higher concentration of glucose has the higher initial adherence property.

OBJECTIVETrying to find out the mechanism of microstructure influencing bacterial adhesion, we prepared different microstructures to compare the adsorptive behavior of graphite powder and adhesive behavior of oral microbe.

METHODSWe used polydimethylsiloxane (PDMS) to copy 23 microstructures of hydroxyapatite (HA) chip, and cultured them with different sizes graphite powder and oral microbes respectively, to observe and compare their behavior on microstructures.

RESULTSThe adsorption of 30-50 microm powder on different microstructures was insignificant, while 10-20 microm powder had maximum adsorption on 10 microm and 20 microm microstructures. Saccharomyces albicans was most likely to adhere to 5 microm microstructures which was equivalent to its own size. However, microstructures had little effect on adhesion of Streptococcus mutans which grew in a chain.

CONCLUSIONThe size of microstructure was the most effective factor that affects the adsorption of non-living powder, and it also had the same effect on the microbial adhesion; but some special bacteria, such as Streptococcus mutans which grew in a chain, was not affected by the sizes or shapes of microstructures.

OBJECTIVEThe aim of this study was to observe the change of bacterial adhesion on pure titanium coated with nitrogen-diamond like carbon (N-DLC) films and to guide the clinical application.

METHODSN-DLC was deposited on titanium using ion plating machine, TiN film, anodic oxide film and non-deposition were used as control, then made specimens adhering on the surface of resin denture base for 6 months. The adhesion of Saccharomyces albicans on the titanium surface was observed using scanning electron microscope, and the roughness was tested by roughness detector.

RESULTSThe number of Saccharomyces albicans adhering on diamond-like carbon film was significantly less than on the other groups (P < 0.05), and the growth of bacterial cell was inhibited and in a poor state. The largest number of adhesion and cell strains grew well on anodic oxide film group and non-deposition control group. The change of surface roughness of N-DLC film was less than other group (P < 0.05).

CONCLUSIONPure titanium coated with N-DLC film reduced the adhesion of Saccharomyces albicans after clinical application, thereby reduced the risk of denture stomatitis.

OBJECTIVETo evaluate the effect of an arginine-containing antihypersensitivity polishing paste on Streptococcus mutans (S. mutans) adhesion to treated dentin.

METHODSDentin discs were treated with acid to expose dentin tubules, and then polished with either pumice or a polishing paste containing arginine. The surface roughness of the treated dentin was measured. The effects of dentin treatment on S. mutans adhesion and glucosyltransferase (GTFs) gene expression were also evaluated.

RESULTSThe surface roughness decreased after polishing with both pumice and arginine-containing polishing paste. Moreover, the polishing paste affected gtfB and gtfC expressions.

CONCLUSIONThe arginine-containing polishing paste affects S. mutans adhesion, as well as gtfB and gtfC expressions. The polishing paste may be used to prevent caries in exposed dentin areas.

OBJECTIVETo observe the surface of Enterococcus faecalis and the dynamic forming process of those biofilms using atomic force microscopy (AFM) in air condition.

METHODSThe surface of Enterococcus faecalis which were dried in air were observed with AFM. We used the cellulose nitrate film to construct the Enterococcus faecalis biofilms model in vitro, and then placed the biofilms under AFM to observe the surface changes of biofilms' development.

RESULTSThe cell surfaces of strain Enterococcus faecalis were not regular because of the presence of the amorphous substance on the colony surface, which congregated globular, fibrous structure. Gradually determined that at 6 h the initial biofilm formed and at 24 h the biofilms maintained the steady-state. AFM height images showed topographical changes due to biofilms' development, which were used to characterize several aspects of the bacterial surface, such as the presence of extracellular polymeric substance, and the biofilms' development stage.

CONCLUSIONApplication of AFM in physiological conditions could be useful in observing Enterococcus faecalis surface ultrastructure and dynamic process of biofilms formation.