In vitro study of vitellogenesis in the blue crab (Callinectes sapidus): Site and control of vitellin synthesis

The purpose of this in vitro study was to evaluate the effect of different surface treatments on the shear bond strength of a resin-based cement to porcelain. Sixty pairs of 50% aluminous porcelain discs were fabricated. In each pair, one disc measured 6 mm in diameter X 3 mm thickness (A) and the other measured 3 mm in diameter X 3mm thickness (B). The specimens were randomly assigned to 6 groups (n=10 pairs of discs), according to the surface treatment: etching with 10% hydrofluoric acid for 2 or 4min (G1 and G2); 50-µm particle aluminum oxide sandblasting for 5 s (G3); sandblasting followed by etching for 2 or 4min (G4 and G5) and control - no treatment (G6). A silane agent was applied to the treated surface of both discs of each pair. Bistite II DC dual-cure resin cement was applied and the B discs were bonded to their respective A discs. Specimens were stored in distilled water at 37ºC for 24 h and were tested in shear strength at a crosshead speed of 2 mm/min. Means in MPa were: G1: 14.21 ± 4.68; G2: 8.92 ± 3.02; G3: 10.04 ± 2.37; G4: 12.74 ± 5.15; G5: 10.99 ± 3.35; G6: 6.09 ± 1.84. Data were compared by one-way ANOVA and Tukey's test at 5% significance level. Bond strength recorded after 2-min acid etching was significantly higher than 4-min etching (p<0.05) and control (p<0.05), but did not differ significantlyfrom sandblasting alone (p>0.05) or followed by etching for 2 or 4 min (p>0.05). Within the limitations of an in vitro study, it may be concluded that 2-min hydrofluoric acid etching produced a favorable micromechanical retention that enhanced resin cement bond strength to porcelain.

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Comparative evaluation of force decay pattern in orthodontic active tiebacks exposed to five different mouth rinses: An in vitro Study

Journal of Dental Research Dental Clinics Dental Prospects ◽

10.34172/joddd.2020.048 ◽

2020 ◽

Vol 14 (4) ◽

pp. 244-249

Author(s):

Amir Hossein Mirhashemi ◽

Atefe Saffar Shahroudi ◽

Keyvan Shahpoorzadeh ◽

Niloofar Habibi Khameneh

Keyword(s):

In Vitro Study ◽

Vitro Study ◽

Control Group ◽

Mouth Rinses ◽

Force Decay ◽

Force Relaxation ◽

Decay Pattern ◽

Initial Force ◽

And Control

Background. This study compared the force decay pattern of two different orthodontic active tiebacks (ATBs) exposed to five different commercially available mouth rinses. Methods. In this in vitro study, 90 transparent ATBs and 90 gray ATBs were divided into six groups; one was the control group, and the others were exposed to one of these mouth rinses twice a day for 60 seconds: Listerine, chlorhexidine, Orthokin, Persica, and fluoride. The initial force of each ATB was 250 g at a 24-mm extension. The force of ATBs was measured on days 1, 7, 14, and 28 using a digital gauge. Results. The highest percentage of force loss was observed between days 14 and 28 (P<0.05). At the end of the study, the Persica group exhibited the highest force degradation in both ATB types. In the transparent ATBs, it was followed by Orthokin, Listerine, fluoride, chlorhexidine, and control groups, respectively. In the gray ATBs, Orthokin, chlorhexidine, control, Listerine, and fluoride groups exhibited the highest force decay in descending order. In some groups, the differences between transparent and gray ATBs were significant. In the control group, the force of transparent ATB was significantly higher than gray ones on days 7 and 14 but not significantly after four weeks. Conclusion. ATBs’ force degradation could be exacerbated by the use of some mouth rinses. There were some differences between force relaxation patterns of transparent and gray ATBs. The data could be beneficial in choosing appropriate O-rings for making ATBs.

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Stannous Fluoride Preventive Effect on Enamel Erosion: An In Vitro Study

Journal of Clinical Medicine ◽

10.3390/jcm9092755 ◽

2020 ◽

Vol 9 (9) ◽

pp. 2755

Author(s):

Alessandra Lucchese ◽

Angelica Bertacci ◽

Antonino Lo Giudice ◽

Elisabetta Polizzi ◽

Enrico Gherlone ◽

...

Keyword(s):

Lactic Acid ◽

Single Dose ◽

In Vitro Study ◽

Vitro Study ◽

Preventive Effect ◽

Acid Attack ◽

Significance Level ◽

Stannous Fluoride ◽

And Control

The aim of this in vitro study was to evaluate the effects of a single dose application of two daily toothpastes on enamel exposed to acid attack. The research was conducted on human molars enamel fragments (n = 72). The two different toothpastes active ingredients were sodium fluoride (NaF) and stannous fluoride (SnF2). They were compared in protecting the surface of the enamel exposed to three acids: citric acid, lactic acid and hydrochloric acid. A spectrophotometer was used to measure the calcium ions and phosphate released in the solutions by the enamel specimens. Afterward, ionic concentrations were analyzed through the t-Student test, in order to estimate the significance level (p < 0.05) of the solubility differences obtained between the treatment and control groups. Finally, sample surfaces were analyzed with scanning electron microscopy and X-ray energy dispersive spectroscopy (SEM/EDX). The two analyzed toothpastes did not reveal any statistically significant variation in the release of calcium and phosphate (p > 0.05). Nevertheless, acid-resistant deposits were detected in samples treated with stannous fluoride and exposed to lactic acid, though the presence of tin ion deposits on samples treated with stannous fluoride was not shown. A single dose of a fluoride-based toothpaste before different acids attack, in simulated oral cavity conditions, did not show a significant preventive effect.

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Repeatability of Intraoral Scanners for Complete Arch Scan of Partially Edentulous Dentitions: An In Vitro Study

Journal of Clinical Medicine ◽

10.3390/jcm8081187 ◽

2019 ◽

Vol 8 (8) ◽

pp. 1187 ◽

Cited By ~ 4

Author(s):

Jae-Hyun Lee ◽

Je-Hyeon Yun ◽

Jung-Suk Han ◽

In-Sung Luke Yeo ◽

Hyung-In Yoon

Keyword(s):

Root Mean Square ◽

In Vitro Study ◽

Vitro Study ◽

Mean Square ◽

Missing Teeth ◽

Rms Error ◽

Scan Data ◽

Edentulous Patients ◽

And Control

Research on whether the number or location of missing teeth affects the accuracy of intraoral scanners in partial edentulous patients is scarce. This study aimed to evaluate the precision of complete-arch scan data of various partial edentulous arches acquired by intraoral scanners. Five different maxillary models were scanned using Carestream CS3600 and Medit i500 scanners. The models employed here were control: Fully dentate; Case 1: Missing a right second premolar and a first molar; Case 2: Missing a right second premolar, a first molar, both left premolars, and a left first molar; Case 3: Missing four incisors and a right canine; and Case 4: Missing four incisors, a left second premolar, and a first molar. Six scans per group were performed and the resulting two datasets were paired to analyze the precision of each group (n = 15). Two-way ANOVA was performed (α = 0.05). The root mean square (RMS) error values in Cases 2, 3, and 4 were significantly higher than those in Case 1 and control. The RMS values of the two intraoral scanners were not significantly different. Scanning precision was significantly lower for both devices when used for scanning dental arches with ≥5 missing teeth.

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Influence of Dentine Pre-Treatment by Sandblasting with Aluminum Oxide in Adhesive Restorations. An In Vitro Study

Materials ◽

10.3390/ma13133026 ◽

2020 ◽

Vol 13 (13) ◽

pp. 3026

Author(s):

Bruna Sinjari ◽

Manlio Santilli ◽

Gianmaria D’Addazio ◽

Imena Rexhepi ◽

Alessia Gigante ◽

...

Keyword(s):

Tensile Stress ◽

Aluminum Oxide ◽

Fracture Strength ◽

In Vitro Study ◽

Vitro Study ◽

Control Group ◽

Mechanical Resistance ◽

Significant Difference ◽

And Control

Dentine pretreatment through sandblasting procedures has been widely studied but no curve test results are currently available. Thus, the aim herein was to in vitro compare the adhesive strength in sandblasted or not samples using a universal testing machine. Thirty -two bovine teeth were divided into two groups, namely test (n = 16 bars), sandblasting with aluminum oxide particles (50 µm) was performed before the adhesion procedures), and control (n = 16 bars), where no sandblasting procedure was performed. A bi-material curve test was used to evaluate the characteristics of the dentine pretreatment in terms of tensile stress and fracture strength. A scanning electron microscope (SEM) was used to analyze the fracture topography in the composite, bonding, dentin, and at the relative interfaces. The results demonstrated a statistically significant difference between the two groups in terms of tensile stress at maximum load showing values of 84.300 ± 51.342 MPa and 35.071 ± 16.609 MPa, respectively for test and control groups (p = 0.033). Moreover, a fracture strength test showed values of 18.543 ± 8.145 MPa for test and 8.186 ± 2.833 MPa for control group (p = 0.008). In conclusion, the sandblasting treatment of the dentine significantly influenced the mechanical resistance of the adhesion in this in vitro study.

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Comparative Evaluation of protective Potential of Toothmin and Novamin Containing Toothpastes on Enamel Surface Under Confocal Microscope: An In Vitro Study

Dental Journal of Advance Studies ◽

10.1055/s-0038-1672055 ◽

2016 ◽

Vol 04 (02) ◽

pp. 113-116 ◽

Cited By ~ 1

Author(s):

Anurag Aggarwal ◽

Shalu Gupta ◽

Kanwarpreet Singh ◽

Simran Bindra

Keyword(s):

In Vitro Study ◽

Vitro Study ◽

Enamel Surface ◽

Control Group ◽

Protective Potential ◽

Study Materials ◽

Prior Application ◽

And Control ◽

Sucrose Phosphate

Abstract Aim: To evaluate the protective potential of calcium sucrose phosphate and novamin containing toothpaste on enamel surface. Settings and Design: In vitro-study. Materials and Methods: This study consisted of 30 samples embedded in orthodontic resin with either buccal or lingual surface exposed. The samples were assigned to either calcium sucrose phosphate containing paste; novamine toothpaste; or control group. The groups were then subjected to cycling in a demineralizing solution and a remineralizing solution. Groups II and III received prior application of calcium sucrose phosphate paste and novamine toothpaste respectively followed by cycling in a demineralizing solution and a remineralizing solution. Following 14 days of cycling, the samples were sectioned and examined using confocal microscopy. The depths of lesions were evaluated. Statistical Analysis: Image Proplus software was used to analyze the images. The values were statistically evaluated using one – way ANOVA and Scheffe's Test. Results and Conclusion: Within the limitations of study it was concluded that enamel surfaces treated with calcium sucrose phosphate paste exhibited the least lesion depths followed by enamel surfaces treated with the novamin tooth paste and control group respectively.

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