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

Materials ◽  
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.

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

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.

scholarly journals Evaluation of the apical microleakage of MTA Fillapex, AH26, and Endofill sealers

2020 ◽  
Vol 23 (3) ◽  
Author(s):  
Saeedeh Galledar ◽  
Robab Farhang ◽  
Malek Abazari ◽  
Parisa Negahdar
Keyword(s):  
Root Canal ◽  
Test Group ◽  
In Vitro Study ◽  
Negative Control ◽  
Vitro Study ◽  
Control Group ◽  
Dye Penetration ◽  
Gutta Percha ◽  
Significant Difference

Objective: Proper apical seal plays an important role in the success of root canal treatment. The most common cause of failure of root canal therapy is known as the lack of adequate apical seal. The aim of this in vitro study was to compare the apical microleakage of MTA Fillapex, , and Endofill sealers using dye penetration method. Material and Methods: In this in vitro study, 72 single-rooted extracted human teeth were selected. The teeth were randomly divided into three experimental groups of 20 and two positive and negative control groups of 6. The canals were prepared by step-back technique and then filled with gutta-percha and one of the sealers mentioned. In the positive control group, the canals were filled with gutta-percha without sealer, and in the negative control group, the canals were prepared but not filled. The teeth were immersed in 2% methylene blue dye for 72 hours. The teeth were then cut longitudinally and the level of dye penetration was measured under a stereomicroscope. Data were analyzed by SPSS ver. 19 software, ANOVA and Bonferroni post-hoc tests. Results: The mean level of dye penetration in the Endofill test group was significantly higher than that in the  and MTA Fillapex test groups. While, the observed difference between  and MTA Fillapex groups was not statistically significant (p<0.05). Conclusion: The results of this study showed that  and MTA Fillapex sealers did not show any significant difference in apical seal properties. However, their sealing strength was significantly greater than Endofill sealer.KeywordsAH26 sealer; Endofill; MTA Fillapex; Microleakag

scholarly journals Comparison of MTA, CEM Cement, and Biodentine as Coronal Plug during Internal Bleaching: An In Vitro Study

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Paridokht Zarean ◽  
Parichehr Zarean ◽  
Arash Ravaghi ◽  
Maryam Zare Jahromi ◽  
Mitra Sadrameli
Keyword(s):  
Root Resorption ◽  
Mineral Trioxide Aggregate ◽  
In Vitro Study ◽  
Negative Control ◽  
Vitro Study ◽  
Control Group ◽  
Endodontically Treated Teeth ◽  
Cem Cement ◽  
Significant Difference

Background. Internal bleaching is a choice of treatment in discolored endodontically treated teeth. Cervical root resorption is one of the important complications of this treatment. A suggested procedure to prevent this type of resorption is using a coronal barrier under the bleaching materials. The aim of the study was to compare the microleakage of mineral trioxide aggregate (MTA), calcium-enriched mixture (CEM) cement, and Biodentine. Materials and Methods. In this in vitro study, a total of 60 single canal incisors were included. They were randomly divided into three experimental groups (n = 16), one positive control group (n = 6), and one negative control group (n = 6). Coronal portion of the canals in the experimental groups was sealed with 3 mm of MTA, CEM cement, or Biodentine as a coronal barrier. After 3 days, specimens were bleached. A fresh Enterococcus faecalis suspension was added to the samples. The culture tubes were observed for 45 days, and the daily turbidity was recorded. Statistical analysis was accomplished by the Kaplan–Meier test and SPSS 22. Results. All positive samples showed turbidity, whereas none of the negative samples allowed bacterial leakage. Results showed no significant difference between MTA, CEM cement, and Biodentine groups. ( P value = 0.304, 0.695, and 0.217). The bacterial microleakage for the two groups also did not show significant differences. Conclusions. CEM cement and Biodentine showed promising results as coronal plug, and clinical studies are needed to test these materials with MTA for avoiding microleakage in internal bleaching treatment.

Leukocyte removal efficiency of cell-washed and unwashed whole blood: an in vitro study

Perfusion ◽  
2005 ◽  
Vol 20 (6) ◽  
pp. 335-341 ◽  
Author(s):  
M J ten Brinke ◽  
P W Weerwind ◽  
S Teerenstra ◽  
J CM Feron ◽  
W van der Meer ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Plasma Volume ◽  
Removal Rate ◽  
In Vitro Study ◽  
Vitro Study ◽  
Control Group ◽  
Leukocyte Depletion ◽  
Porcine Blood ◽  
Significant Difference

Leukocyte filtration of the cardiopulmonary bypass (CPB) perfusate after cardiac surgery has evolved as an important technique to prevent effector functions mediated by activated leukocytes. However, little is known about the filtration efficiency. Therefore, an in vitro study was conducted to define the leukocyte removal rate of a transfusion leukocyte-depletion filter, using cell-washed and unwashed whole porcine blood. In addition, the influence of different cell-washing protocols on the elimination rate of blood cells (leukocytes and platelets) was investigated. Fresh, diluted, pooled, heparinized, porcine blood was processed using either a high-flow (HF, n-5) or quality-wash (QW, n-5) protocol on a continuous auto-transfusion system, or was left unprocessed (control n-5). Thereafter, all samples were filtered using a transfusion leukocyte-depletion filter. Blood samples for measurement of hematocrit, white blood cell count, including leukocyte differentiation and platelet count, were taken before and after filtration. To compare the experimental groups, the removal rate was presented as the fraction of leukocytes or platelets removed per plasma volume. Cell washing significantly altered the fraction of leukocytes removed per plasma volume when compared to unprocessed blood (2.07 and 2.36 in the HF and QW groups, respectively, versus 1.34 in the control group, p-0.008 for both). No statistically significant difference in leukocyte removal rate was observed between the different cell-washing protocols. The leukocyte differential count showed that, during all experiments, the neutrophils were removed most efficiently (99.7%). Overall, significantly more platelets were depleted after cell washing compared to the control group (1.47 and 1.60 in the HF and QW groups, respectively, versus 1.12 in the control group, p-0.008 and 0.032, respectively). Furthermore, the amount of blood that could be filtered using a single pass technique did not significantly differ between the experimental groups. However, a larger variation in the total amount of filtered blood was observed in the unprocessed group (5709/398 mL) compared to the cell-washed groups (3609/42 and 4309/97 mL in the HF and QW groups, respectively). In conclusion, blood processing with an auto-transfusion system significantly enhances the leukocyte and platelet removal efficiency of the transfusion leukocyte-depletion filter that was studied. In particular, neutrophils were efficiently removed.

Comparison of Fracture Strengths among different Commonly Placed Anterior Esthetic Restorations for Primary Dentition: An in vitro study

2021 ◽  
Vol 45 (3) ◽  
pp. 171-176
Author(s):  
Brent Lin ◽  
Amit Khatri ◽  
Michael Hong
Keyword(s):  
Fracture Strength ◽  
Testing Machine ◽  
In Vitro Study ◽  
Vitro Study ◽  
Anterior Teeth ◽  
Study Results ◽  
Luting Cement ◽  
Significant Difference ◽  
All Ceramic

The purpose of this study was to determine and compare the shear force (N) required to fracture or dislodge an all-ceramic zirconia-based crown using different luting cement with those of polycarbonate crown and strip crown for the primary anterior teeth in vitro. Study design: Four groups of esthetic restoration for primary anterior teeth were tested for fracture strength: 1) Fifteen all-ceramic zirconia-based crowns cemented with glass ionomer cement, 2) Fifteen all-ceramic zirconia-based crowns bonded with a self-adhesive resin cement, 3) Fifteen polycarbonate crowns cemented with a polymer reinforced zinc-oxide eugenol and 4) Fifteen resin strip crowns. All restorations were placed and cemented on reproductions of dies in an independent laboratory at Delhi, India. All samples underwent loading until fracture or dislodgement with the Universal Testing Machine. The force in Newton (N) required to produce failure was recorded for each sample and the type of failures was also noted and characterized. One-way analysis of variance (ANOVA) test and the Tukey and Scheffe’s post hoc comparisons were used for statistical analyses. Results: In this invitro study, results were measured in Newtons (N). Group 1 (410.9±79.5 N) and Group 2 (420.5±57.8 N) had higher fracture strength than Group 3 (330.3±85.6 N) and Group 4 (268.4±28.2 N). These differences were statistically significant at P≤.05 among the sample groups. No significant difference was found between groups 1 and 2 (P = 0.984) nor between groups 3 and 4 (P =0.104). Among type of failures, majority of restoration fractures for zirconia-based crowns and resin strip crowns were due to cohesive failures and polycarbonate crowns had predominantly mixed failures. Conclusions: Under the limitations of this in vitro study, it could be concluded that all-ceramic zirconia-based crowns attained the highest fracture strength among all restorative samples tested regardless of the type of luting agent employed (P&lt;.01). Cohesive failures were commonly observed in the zirconia crowns and resin strip crowns, whereas polycarbonate crowns revealed predominately mixed failures.

scholarly journals Adjunct use of mouth rinses with a sonic toothbrush accelerates the detachment of a Streptococcus mutans biofilm: an in vitro study

2020 ◽  
Author(s):  
Tatsuya Ohsumi ◽  
Shoji Takenaka ◽  
Yuuki Sakaue ◽  
Yuki Suzuki ◽  
Ryoko Nagata ◽  
...  
Keyword(s):  
Streptococcus Mutans ◽  
In Vitro Study ◽  
Vitro Study ◽  
Combination Group ◽  
Control Group ◽  
Mouth Rinse ◽  
Biofilm Thickness ◽  
Log Reduction ◽  
Significant Difference

Abstract Background : The aim of this in vitro study was to examine the possible enhancement of the biofilm peeling effect of a sonic toothbrush following the use of an antimicrobial mouth rinse. Methods: The biofilm at a noncontact site in the interdental area was treated by sound wave convection with the test solution or by immersion in the solution. The biofilm peeling effect was evaluated by determining the bacterial counts and performing morphological observations. A Streptococcus mutans biofilm was allowed to develop on composite resin discs by cultivation with stirring at 50 rpm for 72 hours. The specimens were then placed in recesses located between plastic teeth and divided into an immersion group and a combination group. The immersion group was treated with phosphate buffer or Listerine ® mouth rinse. The combination group was treated with Listerine ® and a sonic toothbrush. Results: The biofilm thickness was reduced by approximately one-half compared with the control group. The combination treatment produced a 1 log reduction in the number of bacteria compared to the Listerine ® immersion treatment. No significant difference was observed in the biofilm peeling effect of the immersion group compared to the control group. Conclusions: The combined use of a sonic toothbrush and a mouth rinse enhanced the peeling of the biofilm that proliferates in places that are difficult to reach using mechanical stress.

scholarly journals INFLUENCE OF DIFFERENT BLEACHING SYSTEMS ON THE BOND STRENGTH OF LAMINATE VENEER TO ENAMEL

2018 ◽  
Vol 4 (2) ◽  
pp. 1-6
Author(s):  
Ozgun Yusuf Ozyilmaz ◽  
Filiz Aykent ◽  
Ali Riza Tuncdemir ◽  
Haluk Baris Kara
Keyword(s):  
Bond Strength ◽  
Diode Laser ◽  
In Vitro Study ◽  
Unit Group ◽  
Tooth Surface ◽  
Control Group ◽  
Significant Difference ◽  
And Control ◽  
One Way Anova

Purpose: The objective of this in-vitro study was to examine the microtensile bond strength of a porcelain laminate veneer (PLV)  to tooth surface bleached with photoactivation by blue light-emitting diode (LED) or diode laser. Methods: Eigthteen extracted human central incisors were randomly divided into three groups. Two sticks were obtained from each tooth (n=12). Before surface treatments; teeth were prepared to provide space for PLVs. The first group teeth were bleached with Whiteness HP  which is contain 35% hydrogen peroxide (HP) and then photoactivated with  a LED for 20 seconds. The second  group were bleached with Laserwhite 20  which is contain 46% HP and  photoactivated with a diode laser for 30 seconds. The third group received no surface treatment and served as the control group. IPS Esthetic ceramic veneers were luted with Variolink II veneer cement . The teeth were sectioned to obtain porcelain-resin-enamel/dentin sticks and submitted to a MTB testing device. The maximum load at fracture  was recorded. Data were analyzed using one-way ANOVA followed by the Tukey HSD post-hoc test at a preset  α of  0.05. Results: One-way ANOVA revealed that there was significant difference between LED unit group and control group (p<.05) but  no statistical differences were observed with diode laser group (p>.05)  The LED unit group presented significantly lower bond strength value (6.49±2.3 MPa) than diode laser (8.49±3.1 MPa) and control groups (9.53±2.7 MPa). Conclusion: The results suggested that bleaching therapy with activation by LED or diode laser reduced the bond strength of IPS Esthetic ceramic veneers to tooth surfaces.Keywords: Teeth Bleaching; Photoactivation; Semiconductor lasers; Diode laser; Microtensile.

scholarly journals Adjunct use of mouth rinses with a sonic toothbrush accelerates the detachment of a Streptococcus mutans biofilm: an in vitro study

2020 ◽  
Author(s):  
Tatsuya Ohsumi ◽  
Shoji Takenaka ◽  
Yuuki Sakaue ◽  
Yuki Suzuki ◽  
Ryoko Nagata ◽  
...  
Keyword(s):  
Streptococcus Mutans ◽  
In Vitro Study ◽  
Vitro Study ◽  
Combination Group ◽  
Control Group ◽  
Mouth Rinse ◽  
Biofilm Thickness ◽  
Log Reduction ◽  
Significant Difference

Abstract Background : The aim of this in vitro study was to examine the possible enhancement of the biofilm peeling effect of a sonic toothbrush following the use of an antimicrobial mouth rinse. Methods: The biofilm at a noncontact site in the interdental area was treated by sound wave convection with the test solution or by immersion in the solution. The biofilm peeling effect was evaluated by determining the bacterial counts and performing morphological observations. A Streptococcus mutans biofilm was allowed to develop on composite resin discs by cultivation with stirring at 50 rpm for 72 hours. The specimens were then placed in recesses located between plastic teeth and divided into an immersion group and a combination group. The immersion group was treated with phosphate buffer, Peridex™ mouth rinse or Listerine ® mouth rinse. The combination group was treated with Peridex™ or Listerine ® and a sonic toothbrush. Results: The biofilm thickness was reduced by approximately one-half compared with the control group. The combination treatment produced a 1 log reduction in the number of bacteria compared to the Listerine ® immersion treatment. No significant difference was observed in the biofilm peeling effect of the immersion group compared to the control group. Conclusions: The combined use of a sonic toothbrush and a mouth rinse enhanced the peeling of the biofilm that proliferates in places that are difficult to reach using mechanical stress.

Effect of Prolonged Thermal Cycling on Microleakage around Class V Cavities Restored with Glass-Ceramic Inserts with Different Coefficients of Thermal Expansion. An In Vitro Study

2006 ◽  
Vol os13 (4) ◽  
pp. 147-153
Author(s):  
Ario Santini ◽  
Vladimir Ivanovic ◽  
Chuei Luan Tan ◽  
Richard Ibbetson
Keyword(s):  
Thermal Expansion ◽  
Thermal Cycling ◽  
Glass Ceramic ◽  
Coefficient Of Thermal Expansion ◽  
In Vitro Study ◽  
Vitro Study ◽  
Control Group ◽  
Class V ◽  
Significant Difference

Purpose The purpose of this in vitro study was to evaluate microleakage around Class V glass-ceramic restorations of different coefficients of thermal expansion after prolonged thermal cycling. Materials and Methods One hundred and twenty non-carious extracted human premolars (patient age range 12–20 years) were randomly assigned to three groups. Standard Class V preparations were cut in the buccal surface using customised Cerana burs, size no. 3. Glass-ceramic inserts from two manufacturers (Cerana, Nordiska Dental AB, Helsingborg, Sweden; Beta-Quartz, Hager & Werken GmbH, Duisburg, Germany) were used to restore the cavities and were luted with a hybrid, high-viscous composite (Tetric Ceram, Ivoclar Vivadent, Schaan, Liechtenstein) and a bonding agent (Excite, Ivoclar Vivadent, Schaan, Liechtenstein). A control group, without inserts, was bulk-filled with the same composite used as the luting agent. In accordance with American Dental Association guidelines, half of the preparation was in enamel, half in dentine/cementum and had a mesio-distal width of 3 mm, an occluso-gingival height of 3 mm, and a depth of 2 mm. All margins had butt joints. Sixty teeth, selected at random, were not thermal cycled; the remaining 60 teeth were thermal cycled 4000 times between water baths held at 5°C and 55°C and the specimens prepared and examined for microleakage using 2.0% Procion Red® (ICI, Slough, UK) dye, buffered at pH7, as a marker. The results were analysed using the Kruskal-Wallis test (ANOVA) at a 95% significance level. Results At the occlusal margins there was no significant difference in microleakage between the three groups (P>0.5) without thermal cycling. After thermal cycling, microleakage at the occlusal margins was significantly less around cavities restored with Cerana glass-ceramic inserts versus Beta-Quartz and Tetric Ceram (P<0.05 in both cases). At the gingival margins, there was no significant difference in microleakge between the groups before thermal cycling (P>0.5). After thermal cycling, there was significantly less microleakage between Cerana inserts and Tetric Ceram (P<0.05). Comparisons between non-thermal cycled and thermal cycled groups showed there was no significant difference with the Cerana inserts (P=0.5590). Clinical Implications The results indicate that, after thermal cycling, restorations restored with Cerana glass-ceramic inserts, which have a coefficient of thermal expansion approximating to that of enamel, show a decrease in marginal microleakage, compared with Beta-Quartz glass-ceramic inserts and Tetric Ceram resin-based composite material. Restorative materials, which have a coefficient of thermal expansion approximating to that of enamel, would seem to be the materials of choice in reducing the problem of marginal microleakege.

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

2016 ◽  
Vol 04 (02) ◽  
pp. 113-116 ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document