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The Journal of Prosthetic Dentistry Mar 2019The prosthodontic problems faced by a patient with xerostomia are of great concern. To aid in retention, artificial saliva substitutes should exhibit good wettability on...
STATEMENT OF PROBLEM
The prosthodontic problems faced by a patient with xerostomia are of great concern. To aid in retention, artificial saliva substitutes should exhibit good wettability on the denture base.
PURPOSE
The purpose of this in vitro study was to evaluate the wettability of 3 different artificial saliva substitutes on heat-polymerized acrylic resin and to compare these properties with natural saliva and distilled water.
MATERIAL AND METHODS
A total of 150 heat-polymerized acrylic resin specimens were prepared with 25×15×2 mm dimensions. The specimens were divided into 5 groups (n=30): human saliva, distilled water, Aqwet, Mouth Kote, and Stoppers 4. The advancing and receding contact angle values were measured by using a goniometer, and the contact angle hysteresis and equilibrium angle were calculated. One-way ANOVA and the Bonferroni multiple comparisons test were performed to determine the difference between contact angle values among the groups (α=.05).
RESULTS
The means of the 5 groups differed significantly (P<.05). The comparison between human saliva and Aqwet showed no significant difference for advancing contact angle, receding contact angle, contact angle hysteresis, or equilibrium contact angle, while comparison between the remaining groups indicated statistically significant (P<.05) results. All 3 saliva substitutes used in this study (Aqwet, Mouth Kote, and Stoppers 4) had significantly better wetting properties than distilled water.
CONCLUSIONS
Human saliva had the lowest advancing, receding, and equilibrium contact angle values and the highest angle of hysteresis on heat-polymerized acrylic resin. Aqwet had better wetting ability than the other artificial salivary substitutes tested and was comparable to the human saliva on heat-polymerized acrylic resin. All saliva substitutes have better wetting properties than distilled water.
Topics: Acrylic Resins; Denture Bases; Hot Temperature; Humans; Materials Testing; Saliva, Artificial; Wettability
PubMed: 30391058
DOI: 10.1016/j.prosdent.2018.03.037 -
The Journal of Prosthetic Dentistry Jul 2016The mechanical properties of new titanium alloys with an elastic modulus closest to cortical bone have been studied. However, potentially damaging conditions experienced...
STATEMENT OF PROBLEM
The mechanical properties of new titanium alloys with an elastic modulus closest to cortical bone have been studied. However, potentially damaging conditions experienced in the oral cavity, such as fluoride ions, can initiate a localized or crevice process of corrosive degradation in the alloy surfaces.
PURPOSE
The purpose of this in vitro study was to evaluate the effects of long-term immersion in artificial saliva or in fluoride solution on mean roughness (Ra), Vickers hardness, and topography of the new titanium alloy Ti-35Nb-7Zr-5Ta (TNZT) compared with those of cp Ti and Ti-6Al-4V (TAV).
MATERIAL AND METHODS
Disks (N=210) were divided into cp Ti, TAV, and TNZT and subdivided according to the following treatments: no immersion (N(-), control), immersion in artificial saliva (S), and immersion in fluoride (F) during periods equivalent to 5, 10, 15, and 20 years. The Ra and Vickers hardness were measured with a profilometer and a hardness tester. The topography was analyzed by scanning electronic microscopy. Data were compared using the Kruskal-Wallis and Dunn tests (α=.05).
RESULTS
Values of Ra and hardness were significantly different among the metals (Ra: TAV
CONCLUSIONS
Long-term immersion in NaF did not change the roughness of Ti-35Nb-7Zr-5Ta. However, the hardness of the alloys increased with immersion.
Topics: Dental Alloys; Dental Materials; Elasticity; Fluorides; Hardness; In Vitro Techniques; Saliva, Artificial; Surface Properties; Titanium
PubMed: 26831918
DOI: 10.1016/j.prosdent.2015.10.024 -
Ion Release and Galvanic Corrosion of Different Orthodontic Brackets and Wires in Artificial Saliva.The Journal of Contemporary Dental... Mar 2017To investigate the galvanic corrosion of brackets manufactured by four different companies coupled with stainless steel (SS) or nickel-titanium (NiTi) wires in an...
INTRODUCTION
To investigate the galvanic corrosion of brackets manufactured by four different companies coupled with stainless steel (SS) or nickel-titanium (NiTi) wires in an artificial saliva solution.
MATERIALS AND METHODS
A total of 24 mandibular central incisor Roth brackets of four different manufacturers (American Orthodontics, Dentaurum, Shinye, ORJ) were used in this experimental study. These brackets were immersed in artificial saliva along with SS or NiTi orthodontic wires (0.016'', round) for 28 days. The electric potential difference of each bracket/ wire coupled with a saturated calomel reference electrode was measured via a voltmeter and recorded constantly. Corrosion rate (CR) was calculated, and release of ions was measured with an atomic absorption spectrometer. Stereomicroscope was used to evaluate all samples. Then, samples with corrosion were further assessed by scanning electron microscope and energy-dispersive X-ray spectroscopy. Two-way analysis of variance was used to analyze data.
RESULTS
Among ions evaluated, release of nickel ions from Shinye brackets was significantly higher than that of other brackets. The mean potential difference was significantly lower in specimens containing a couple of Shinye brackets and SS wire compared with other specimens. No significant difference was observed in the mean CR of various groups (p > 0.05). Microscopic evaluation showed corrosion in two samples only: Shinye bracket coupled with SS wire and American Orthodontics bracket coupled with NiTi wire.
CONCLUSION
Shinye brackets coupled with SS wire showed more susceptibility to galvanic corrosion. There were no significant differences among specimens in terms of the CR or released ions except the release of Ni ions, which was higher in Shinye brackets.
Topics: Alloys; Corrosion; Electrochemistry; Humans; Ions; Orthodontic Brackets; Orthodontic Wires; Saliva, Artificial; Spectrometry, X-Ray Emission; Spectrophotometry, Atomic; Stainless Steel
PubMed: 28258269
DOI: No ID Found -
ACS Sensors Feb 2023The COVID-19 pandemic has caused over 7 million deaths worldwide and over 1 million deaths in the US as of October 15, 2022. Virus testing lags behind the level or...
The COVID-19 pandemic has caused over 7 million deaths worldwide and over 1 million deaths in the US as of October 15, 2022. Virus testing lags behind the level or availability necessary for pandemic events like COVID-19, especially in resource-limited settings. Here, we report a low cost, mix-and-read COVID-19 assay using a synthetic SARS-CoV-2 sensor, imaged and processed using a smartphone. The assay was optimized for saliva and employs 3D-printed micropipette tips with a layer of monoclonal anti-SARS-CoV-2 inside the tip. A polymeric sensor for SARS-CoV-2 spike (S) protein (COVRs) synthesized as a thin film on silica nanoparticles provides 3,3',5-5'-tetramethylbenzidine responsive color detection using streptavidin-poly-horseradish peroxidase (ST-poly-HRP) with 400 HRP labels per molecule. COVRs were engineered with an NHS-PEG-biotin coating to reduce nonspecific binding and provide affinity for ST-poly-HRP labels. COVRs binds to S-proteins with binding strengths and capacities much larger than salivary proteins in 10% artificial saliva-0.01%-Triton X-100 (as virus deactivator). A limit of detection (LOD) of 200 TCID/mL (TCID = tissue culture infectious dose 50%) in artificial saliva was obtained using the Color Grab smartphone app and verified using ImageJ. Viral load values obtained in 10% pooled human saliva spiked with inactivated SARS-COV-2 virus gave excellent correlation with viral loads obtained from qPCR ( = 0.0003, = 0.99).
Topics: Humans; COVID-19; SARS-CoV-2; Smartphone; Saliva, Artificial; Pandemics; Horseradish Peroxidase; Printing, Three-Dimensional
PubMed: 36689276
DOI: 10.1021/acssensors.2c02516 -
Operative Dentistry Sep 2022The purpose of this study was to evaluate the leaching pattern of different types of polymer computer-aided design and computer-aided manufacturing (CAD-CAM) materials...
PURPOSE
The purpose of this study was to evaluate the leaching pattern of different types of polymer computer-aided design and computer-aided manufacturing (CAD-CAM) materials with a conventional resin composite.
METHODS AND MATERIALS
Specimens of three representatives by type of polymer CAD-CAM blocks and one conventional resin composite were suspended using a silk thread in distilled water and artificial saliva. After one day, seven days, 14 days, 30 days, and 60 days, the analysis of the eluates for the detection of bisphenol A (BPA), urethane dimethacrylate (UDMA), triethylene glycol dimethacrylate (TEGDMA) and bisphenol A-glycidyl dimethacrylate (Bis-GMA) was quantified by utilizing high-performance liquid chromatography (HPLC).
RESULTS
TEGDMA was the main eluted monomer for the polymer CAD-CAM materials for both solutions. However, there was a decreasing pattern throughout the tested period. On the contrary, there was a constant release of monomers from the conventional resin composite. Bisphenol-A was released only by the conventional resin composite and in both solutions chosen.
CONCLUSIONS
Different types of polymer CAD-CAM materials release minimal or no monomers compared to the conventional resin composite material. The methods of fabrication of polymer CAD-CAM materials produces better properties than the conventional resin composite with a dramatic decrease of monomer elution.
Topics: Bisphenol A-Glycidyl Methacrylate; Composite Resins; Computer-Aided Design; Dental Materials; Materials Testing; Polyethylene Glycols; Polymers; Polymethacrylic Acids; Saliva, Artificial; Silk; Water
PubMed: 36026705
DOI: 10.2341/21-079-L -
BMC Oral Health Dec 2023To compare force degradation of elastomeric chains and NiTi coil springs in vivo and in vitro, and evaluate the effects of pre-stretched and reused elastomeric chains in...
OBJECTIVE
To compare force degradation of elastomeric chains and NiTi coil springs in vivo and in vitro, and evaluate the effects of pre-stretched and reused elastomeric chains in the oral cavity during the time.
METHODS
In the in vitro groups, 4-unit elastomeric chains and NiTi coil springs with an initial force of 200 g were placed in dry air and artificial saliva. The volunteers wore clear retainers which were used to hold the sample of 4-unit chains, pre-stretched 4-unit chains, and NiTi coil springs with the initial force of 200 g in the in vivo groups. After the first 4 weeks, 4-unit specimens were stretched to 200 g again for another 4 weeks in vivo. The force value and the percentage of force degradation were recorded at each measurement time interval in the in vivo and in vitro groups.
RESULTS
The force degradation of elastomeric chains was greatest within the initial 4 hours, followed by a more stable phase after 1 week. The average force degradation of 4-unit elastomeric chains after 4 weeks was in vivo (64.8%) > artificial saliva (55.0%) > dry air (46.42%) (P < 0.05). The force degradation of NiTi coil springs in vivo (15.36%) or in artificial saliva (15.8%) was greater than in dry air (7.6%) (P < 0.05). NiTi coil springs presented a gentler force decay than elastomeric chains during the period (P < 0.05). In vivo, the force degradation of pre-stretched and reused elastomeric chains decreased less than the regular style(P < 0.05).
CONCLUSION
The force degradation of the elastomeric chains and NiTi coil springs varied in different environments. NiTi coil springs presented a gentler force decay than elastomeric chains during the period. Orthodontists should consider the force degradation characteristics of orthodontic accessories in clinical practice.
Topics: Humans; Saliva, Artificial; Nickel; Titanium; Elasticity; Orthodontic Appliances; Materials Testing; Orthodontic Wires
PubMed: 38097980
DOI: 10.1186/s12903-023-03737-x -
Operative Dentistry Mar 2023This study aimed to evaluate the effect of activated charcoal toothpaste on the color stability of teeth subjected to tooth bleaching and pigmenting agents.
OBJECTIVE
This study aimed to evaluate the effect of activated charcoal toothpaste on the color stability of teeth subjected to tooth bleaching and pigmenting agents.
METHODS
A total of 120 bovine crowns were randomly divided into 12 groups (n=10) according to two study factors: staining solutions (three levels): saliva (control), coffee, and red wine; and toothpaste (four levels): BPC, Bianco Pro Clinical (Bianco Oral Care) (Control); BIW, Black is White (Curaprox); BCA, Bianco Carbon (Bianco Oral Care); and NAT, Natural Suavetex (Suavetex). The samples were subjected to office bleaching with a 35% hydrogen peroxide-based gel (Whiteness HP Blue, FGM), followed by immersion in the solution for 45 minutes per day and daily toothbrushing for 7 days. The color (ΔE) and luminosity changes (ΔL*) were measured using reflectance spectroscopy (Vita EasyShade). The CIE values (L*, a*, b*) were measured at baseline after bleaching (T0) and immediately after immersion in solution each day (Ti1-Ti7) and after all toothbrushing cycles (Tb1-Tb7). ΔE and ΔL were analyzed using a two-way analysis of variance and Tukey's test (α=0.05). The clinically unacceptable level of ΔE > 3.3 was used to evaluate the color change.
RESULTS
The color change was significantly influenced by the staining solutions and toothpastes (p<0.001). The color change (ΔE) was significantly higher when immersed in wine than in coffee, and lower ΔE values were observed for artificial saliva (control), irrespective of the toothpaste used. In artificial saliva, BPC, BIW, and BCA resulted in significantly lower ΔE values than NAT, which presented a clinically unacceptable level of dental color change (ΔE>3.3). Coffee resulted in a lower (L*) reduction than wine, irrespective of the toothpaste used.
CONCLUSION
Charcoal toothpastes resulted in a color change on the surface of the tooth enamel (ΔE). The bleaching effect of the charcoal toothpastes and control evaluated in this study partially reduced the color changes on the surface of the tooth enamel caused by staining solutions but was unable to reestablish the measured values to the baseline. For teeth immersed in artificial saliva, the color change was not noticeable in BCA, BIW, and control-BPC (ΔE≥3.3), except for NAT, which showed a significant color change.
Topics: Animals; Cattle; Charcoal; Coffee; Color; Saliva, Artificial; Tooth Bleaching; Toothpastes
PubMed: 36656320
DOI: 10.2341/21-158-L -
Oral Diseases Sep 2018To investigate whether saliva formulations with reduced calcium (Ca) and inorganic phosphorous (Pi) concentration would affect dental erosion caused by hydrochloric acid...
OBJECTIVES
To investigate whether saliva formulations with reduced calcium (Ca) and inorganic phosphorous (Pi) concentration would affect dental erosion caused by hydrochloric acid (HCl).
METHODS
Enamel and root dentine bovine slabs were embedded, polished, and measured for surface Knoop microhardness (SMH). After reference areas were created, specimens were exposed to HCl solution (0.01 M; pH 2; 120 s) and immersed in artificial salivas (6 hr) containing three different Ca/Pi concentrations (n = 15), which simulate serum conditions of normo-, mild, or severe hypocalcemia. The control group was immersed in Ca/Pi-free saliva. The study protocol was carried out 2×/day for 5 days. Surface loss of enamel and root dentine was assessed using an optical profilometer, and SMH was remeasured for enamel.
RESULTS
One-way analysis of variance (p < .001) and Tukey's test showed that enamel loss in groups subjected to artificial salivas that simulated mild or severe hypocalcemia did not differ from that resembling normocalcemia. %SMH was lower when saliva was mildly and normally concentrated in Ca/Pi (p < .001). Root dentine loss was higher in saliva simulating severe hypocalcemia than in those referring to mild, hypo-, and normocalcemia.
CONCLUSIONS
Depending on the dental substrate, salivary formulations resembling serum hypocalcemia affected surface loss due to erosion and rehardening thereof.
Topics: Animals; Calcium; Cattle; Dental Enamel; Dentin; Hydrochloric Acid; Phosphorus; Saliva, Artificial; Tooth Erosion
PubMed: 29423930
DOI: 10.1111/odi.12843 -
African Health Sciences Sep 2014Dry mouth is usually caused by a reduced salivary flow or by changes in the biochemical composition of saliva. (Review)
Review
BACKGROUND
Dry mouth is usually caused by a reduced salivary flow or by changes in the biochemical composition of saliva.
OBJECTIVE
The aim of this paper is a review of the update literature of dry mouth.
METHODS
We search in pubmed in the past 10 years using the words «dry mouth», «causes», «symptoms», «treatment» and «dentistry». A large number of papers have been identified. Papers not relevant to the issue were removed reducing the entries to 56 only.
RESULTS
There are no clearly established protocols for the treatment of dry mouth in the literature. Most of identified papers were systematic reviews, non-systematic reviews, and observational studies. The most studied patients were Sjögren's syndrome and the irradiated patients. Treatments are focused on the etiology, prevention, symptomatic, local salivary stimulation and systemic treatments.
CONCLUSION
It can be concluded that there is no clear evidence for the causes and treatment of dry mouth, therefore the majority of the general dental practitioners refer most of the cases to appropriate specialist. Treatment must be individualized, salivary substitutes and mechanical stimulation techniques can be applied.
Topics: Dentists; Health Knowledge, Attitudes, Practice; Humans; Practice Guidelines as Topic; Saliva, Artificial; Salivation; Sjogren's Syndrome; Xerostomia
PubMed: 25352896
DOI: 10.4314/ahs.v14i3.33 -
Skin Research and Technology : Official... Nov 2018The purpose of this research is to characterize the effects of mouthwash solutions on oral friction and moisture using a quantitative in vitro approach.
BACKGROUND
The purpose of this research is to characterize the effects of mouthwash solutions on oral friction and moisture using a quantitative in vitro approach.
MATERIALS AND METHODS
The frictional coefficient of in vitro porcine tongue samples was measured using a magnetic levitation haptic device equipped with a custom tactor designed to mimic human skin. A commercially available moisture meter was used to measure moisture content of the samples. Tongue samples were first tested before treatment, then after application of saliva (either human or artificial), and again after application of 1 of 11 different mouthwash solutions.
RESULTS
The data indicate that the samples treated with artificial saliva vs real saliva have comparable friction coefficient and moisture content. Furthermore, the moisture and friction coefficient remain relatively constant for up to 60 minutes after exposure to ambient conditions. Samples treated with artificial saliva have an average friction coefficient in the range of 0.70-0.80. Application of mouthwash solutions produced an average friction coefficient of 0.39-0.49 but retained the high moisture content of the artificial salivary layer. Several mouthwash solutions resulted in statistically significant differences in the friction coefficient relative to each other.
CONCLUSION
The results of this study demonstrate that a magnetic levitation device can be an effective tool for in vitro oral tribology and that artificial saliva is an effective substitute for real saliva in extended in vitro experiments. The application of mouthwash generally reduces the coefficient of friction of the tongue samples while preserving a relatively high moisture level, and some mouthwashes reduce friction significantly more than others.
Topics: Animals; Friction; In Vitro Techniques; Mouthwashes; Saliva; Saliva, Artificial; Swine; Tongue
PubMed: 29736996
DOI: 10.1111/srt.12579