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van der Mei HC White D Cox E Geertsema-Doornbusch G Busscher H 《The Journal of clinical dentistry》2002,13(1):44-49
This study compared the detachment by supernates of nine different dentifrices of four oral bacterial strains adhering to a salivary pellicle in a parallel plate flow chamber. Ultra-thin bovine enamel slabs were coated for 1.5 h with human whole saliva. Following buffer rinsing, a bacterial suspension of Streptococcus oralis, Streptococcus sanguis, Streptococcus mutans or Actinomyces naeslundii was perfused through the flow chamber at a shear rate of 30 s-1 for four hours, and the number of adhering bacteria n4h was enumerated by image analysis after buffer rinsing at the same shear rate. Then, a 25 wt%-dentifrice/water supernate was perfused through the flow chamber for four minutes, followed by eight minutes of buffer rinsing and another enumeration of the number of bacteria that had remained adhering nad. Finally, an air-bubble was passed through the flow chamber to mimic the occasionally high detachment forces occurring in the oral cavity, and the adhering bacteria nab were counted again. On average, S. sanguis was the easiest to detach (73% averaged over all dentifrice supernates), while A. naeslundii was the most difficult (22% on average). The combined detachment of bacteria by dentifrice supernates and air-bubble ranged from a low of 16% to a high of 80%. Dentifrices containing pyrophosphate and polymeric polyphosphate (hexametaphosphate) surface active ingredients appeared to produce the most consistent and strongest desorption effects on plaque bacteria. Factors apparently important to bacterial detachment from pellicle-covered tooth surfaces by dentifrice formulations include the nature of adhesion of bacterial strains and chemical composition of the dentifrice formulations, including pH, surfactant system and the effect of added ingredients (dispersants, metal ions, peroxides, baking soda). 相似文献
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van der Mei HC White DJ Atema-Smit J Geertsema-Doornbusch GI Busscher HJ 《Clinical oral investigations》2012,16(1):109-115
Salivary conditioning films (SCFs) form on all surfaces exposed to the oral cavity and control diverse oral surface phenomena.
Oral chemotherapeutics and dietary components present perturbations to SCFs. Here we determine the surface energetics of SCFs
through contact angle measurements with various liquids on SCFs following perturbations with a variety of chemotherapeutics
as well as after renewed SCF formation. Sixteen-hour SCFs on polished enamel surfaces were treated with a variety of chemotherapeutics,
including toothpastes and mouthrinses. After treatment with chemotherapeutics, a SCF was applied again for 3 h. Contact angles
with four different liquids on untreated and treated SCF-coated enamel surfaces were measured and surface free energies were
calculated. Perturbations either caused the SCF to become more polar or more apolar, but in all cases, renewed SCF formation
compensated these changes. Thus, a polar SCF attracts different salivary proteins or adsorbs proteins in a different conformation
to create a more apolar SCF surface after renewed SCF formation and vice versa for apolar SCFs. This polar–apolar layering
in SCF formation presents a powerful mechanism in the oral cavity to maintain surface thermodynamic homeostasis—defining oral
surface properties within a narrow, biological range and influencing chemotherapeutic strategies. Surface chemical changes
brought about by dietary or chemotherapeutic perturbations to SCFs make it more polar or apolar, but new SCFs are rapidly
formed compensating for changes in surface energetics. 相似文献
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Van Hoogmoed CG Geertsema-Doornbusch GI Teughels W Quirynen M Busscher HJ Van der Mei HC 《Oral microbiology and immunology》2008,23(1):43-48
INTRODUCTION: Periodontitis results from a shift in the subgingival microflora into a more pathogenic direction with Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans considered as periodontopathogens. In many cases, treatment procures only a temporary shift towards a less pathogenic microflora. An alternative treatment could be the deliberate colonization of pockets with antagonistic microorganisms to control the adhesion of periodontopathogens. The aim of this study was to identify bacterial strains that reduce adhesion of periodontopathogens to surfaces. METHODS: Streptococcus sanguinis, Streptococcus crista, Streptococcus salivarius, Streptococcus mitis, Actinomyces naeslundii, and Haemophilus parainfluenzae were evaluated as potential antagonists against P. gingivalis ATCC 33277, P. intermedia ATCC 49046, and A. actinomycetemcomitans ATCC 43718 as periodontopathogens. Adhesion of periodontopathogens to the bottom plate of a parallel plate flow chamber was studied in the absence (control) and the presence of pre-adhering antagonistic strains up to a surface coverage of 5%. RESULTS: The largest reduction caused by antagonistic strains was observed for P. gingivalis. All antagonistic strains except S. crista ATCC 49999 inhibited the adhesion of P. gingivalis by at least 1.6 cells per adhering antagonist, with the largest significant reduction observed for A. naeslundii ATCC 51655 (3.8 cells per adhering antagonist). Adhering antagonists had a minimal effect on the adhesion of A. actinomycetemcomitans ATCC 43718. Intermediate but significant reductions were perceived for P. intermedia, most notably caused by S. mitis BMS. CONCLUSION: The adhesion of P. gingivalis was inhibited best by antagonistic strains, while S. mitis BMS appeared to be the most successful antagonist. 相似文献
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Busscher HJ White DJ Atema-Smit J Geertsema-Doornbusch G de Vries J van der Mei HC 《Journal of clinical periodontology》2008,35(6):547-554
Aim: To compare effects of three cetylpyridinium chloride (CPC) formulations with and without alcohol and Tween80 on physico‐chemical properties of salivary pellicles, bacterial detachment in vitro and bacterial killing in vivo. Material and Methods: Adsorption of CPC to salivary pellicles in vitro was studied using X‐ray photoelectron spectroscopy and water contact angle measurements. Adhesion and detachment of a co‐adhering bacterial pair was determined in vitro using a flow chamber. Killing was evaluated after live/dead staining after acute single use in vivo on 24‐ and 72‐h‐old plaques after 2‐week continuous use. Results: The most pronounced effects on pellicle surface chemistry and hydrophobicity were observed after treatment with the alcohol‐free formulation, while the pellicle thickness was not affected by any of the formulations. All CPC formulations detached up to 33% of the co‐adhering pair from pellicle surfaces. Bacterial aggregate sizes during de novo deposition were enhanced after treatment with the alcohol‐free formulation. Immediate and sustained killing in 24 and 72 h plaques after in vivo, acute single use as well as after 2‐week continuous use were highest for the alcohol‐free formulation. Conclusions: CPC bioavailability in a formulation without alcohol and Tween80 could be demonstrated through measures of pellicle surface properties and bacterial interactions in vitro as well as bacteriocidal actions on oral biofilms in vivo. 相似文献
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