Effect of air-polishing on properties of nanocomposite submitted to coffee, red wine and cigarette smoke

AIM: The aim of this study was to evaluate the surface roughness and the color stability of nanocomposite exposed to the sodium bicarbonate air-polishing (SBAP) followed by red wine, coffee and cigarette smoke exposure. MATERIALS AND METHODS: 64 nanocomposite specimens were prepared and allocated in 8 groups: G1 (SBAP + distilled water), G2 (SBAP + coffee), G3 (SBAP + red wine), G4 (SBAP + cigarette smoke), G5 (distilled water), G6 (coffee), G7 (red wine) and G8 (cigarette smoke). The surface roughness was evaluated in three periods: before and after SBAP and after exposuring to agents tested. The color was evaluated according to CIEL*a*b* parameters using reflection spectrophotometer in two moments: initial and 30 days after the exposure to staining agents. Data were subjected to three-way repeated measures ANOVA and Tukey’s test (5%). RESULTS: The results showed a higher surface roughness of the nanocomposite submitted only to the SBAP and those exposed to the SBAP followed by exposure to the coffee or wine solution. The previous application of SBAP followed by cigarette smoke exposure did not increase the roughness of nanocomposite. The SBAP procedure just increased the staining for cigarette smoke group. CONCLUSION: The SBAP increases resin surface roughness, which worsens when there is exposure to coffee and red wine solution. In addition, SBAP may also provide increased staining of nanocomposites exposed to cigarette smoke.

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The effect of drinks on color stability and surface roughness of nanocomposites

European Journal of Dentistry ◽

10.4103/1305-7456.137640 ◽

2014 ◽

Vol 08 (03) ◽

pp. 330-336 ◽

Cited By ~ 19

Author(s):

Maria Luísa de Alencar e Silva Leite ◽

Fábia Danielle Sales da Cunha Medeiros e Silva ◽

Sônia Saeger Meireles ◽

Rosângela Marques Duarte ◽

Ana Karina Maciel Andrade

Keyword(s):

Surface Roughness ◽

Red Wine ◽

Color Change ◽

Grape Juice ◽

Color Stability ◽

Distilled Water ◽

Initial Surface ◽

Storage Solution

ABSTRACT Objective: The aim was to evaluate the color and surface roughness of nanoparticle (C1) and nanohybrid (C2) composites after immersion in distilled water, acai juice, grape juice and red wine and repolishing. Materials and Methods: After recording the initial surface roughness and color, the specimens were divided into four groups according to the storage solution. The specimens were reassessed after immersion for 1, 2, 4, 8, and 12 weeks and after repolishing. Results: The results showed that after 2 weeks, there were statistically significant changes in color of both resins in all groups, with the exception of the specimens stored in distilled water (P > 0.05). Only 12 weeks of immersion in red wine changed the roughness of composite C1 (P = 0.009). Conclusions: Red wine produced the greatest color change in nanocomposites, followed by grape juice. Acai juice made the color unacceptable clinically only after 12 weeks. Repolishing reduced the color change in all groups.

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Excess mucus viscosity and airway dehydration impact COPD airway clearance

European Respiratory Journal ◽

10.1183/13993003.00419-2019 ◽

2019 ◽

Vol 55 (1) ◽

pp. 1900419 ◽

Cited By ~ 4

Author(s):

Vivian Y. Lin ◽

Niroop Kaza ◽

Susan E. Birket ◽

Harrison Kim ◽

Lloyd J. Edwards ◽

...

Keyword(s):

Cigarette Smoke ◽

Repeated Measures ◽

Mucociliary Clearance ◽

Beat Frequency ◽

Airway Epithelial Cells ◽

Smoke Exposure ◽

Cigarette Smoke Exposure ◽

Chronic Obstructive ◽

Mucus Clearance

The mechanisms by which cigarette smoking impairs airway mucus clearance are not well understood. We recently established a ferret model of cigarette smoke-induced chronic obstructive pulmonary disease (COPD) exhibiting chronic bronchitis. We investigated the effects of cigarette smoke on mucociliary transport (MCT).Adult ferrets were exposed to cigarette smoke for 6 months, with in vivo mucociliary clearance measured by technetium-labelled DTPA retention. Excised tracheae were imaged with micro-optical coherence tomography. Mucus changes in primary human airway epithelial cells and ex vivo ferret airways were assessed by histology and particle tracking microrheology. Linear mixed models for repeated measures identified key determinants of MCT.Compared to air controls, cigarette smoke-exposed ferrets exhibited mucus hypersecretion, delayed mucociliary clearance (−89.0%, p<0.01) and impaired tracheal MCT (−29.4%, p<0.05). Cholinergic stimulus augmented airway surface liquid (ASL) depth (5.8±0.3 to 7.3±0.6 µm, p<0.0001) and restored MCT (6.8±0.8 to 12.9±1.2 mm·min−1, p<0.0001). Mixed model analysis controlling for covariates indicated smoking exposure, mucus hydration (ASL) and ciliary beat frequency were important predictors of MCT. Ferret mucus was hyperviscous following smoke exposure in vivo or in vitro, and contributed to diminished MCT. Primary cells from smokers with and without COPD recapitulated these findings, which persisted despite the absence of continued smoke exposure.Cigarette smoke impairs MCT by inducing airway dehydration and increased mucus viscosity, and can be partially abrogated by cholinergic secretion of fluid secretion. These data elucidate the detrimental effects of cigarette smoke exposure on mucus clearance and suggest additional avenues for therapeutic intervention.

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