Effect of 5% Calcium Hypochlorite on Mechanical Properties of Root Dentin: An in vitro Study

ABSTRACT Introduction The aim of this study was to compare in vitro the effect of 5% calcium hypochlorite [Ca(OCl)2] and 5% sodium hypochlorite (NaOCl) on flexural strength and modulus of elasticity of root dentin. Materials and methods The available chlorine concentration of each solution was determined using iodometric titration. Standardized planoparallel dentin bars (n= 20) were divided into two test groups and one control group. The control, group 1, consisted of dentin bars stored in normal saline. The dentin bars in the two test groups were treated by exposure to following solutions: Group 2 to 5% Ca(OCl)2; and group 3 to 5% NaOCl. All the three test solutions were changed once in 15 minutes for 30 minutes. The dentin bars were then loaded to failure using three-point bend test. Results Available chlorine concentration was 64% in both the test solutions. There was a significant reduction in the flexural strength of 5% NaOCl group compared to 5% Ca(OCl)2-treated ones. A significant difference in modulus of elasticity was observed between the test groups and the control groups and also between the 5% Ca(OCl)2 and 5% NaOCl groups. Conclusion Within the limitations of this study, 5% NaOCl reduced the flexural strength and modulus of elasticity of root dentin bars more when compared to 5% Ca(OCl)2. How to cite this article Reddy P, Balla S, Raghu SS, Velmurugan N, Gupta GT, Sahoo HS. Effect of 5% Calcium Hypochlorite on Mechanical Properties of Root Dentin: An in vitro Study. J Oper Dent Endod 2016;1(2):56-59.

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Flexural strength and modulus of elasticity of different types of resin-based composites

Brazilian Oral Research ◽

10.1590/s1806-83242007000100003 ◽

2007 ◽

Vol 21 (1) ◽

pp. 16-21 ◽

Cited By ~ 70

Author(s):

Sinval Adalberto Rodrigues Junior ◽

Cesar Henrique Zanchi ◽

Rodrigo Varella de Carvalho ◽

Flávio Fernando Demarco

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Modulus Of Elasticity ◽

Filler Content ◽

Hybrid Composites ◽

In Vitro Study ◽

Bending Test ◽

Test Machine ◽

Weight Content

The aim of the study was to test whether the filler composition of resin composites influences their flexural strength and modulus of elasticity. Flexural strength and modulus of elasticity were obtained through a three-point bending test. Twelve bar shaped specimens of 5 commercially available composites - Supreme (3M/ESPE), a universal nanofilled composite; Esthet-X (Dentsply), Z-250 (3M/ESPE), Charisma (Heraeus Kulzer), universal hybrid composites; and Helio Fill (Vigodent), a microfine composite - were confectioned according to the ISO 4049/2000 specifications. The test was performed after a 7-days storage time using a universal test machine with a crosshead speed of 1 mm/min. The filler weight content was determined by the ashing technique. The data obtained on the mechanical properties were submitted to ANOVA and Tukey test (p < 0.05). Pearson's correlation test was used to determine the correlation between the filler content and the mechanical properties. A weak but significant correlation between the mechanical properties evaluated and the filler weight content was observed (p < 0.000). The microfine composite presented the lowest filler weight and the lowest mechanical properties. Statistically different flexural strength and modulus of elasticity results were observed among the universal hybrid composites. The nanofilled composite presented intermediary results. Within the limitations of this in vitro study, it could be concluded that the filler content significantly interfered in the flexural strength and modulus of elasticity of the composites tested.

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Effect of chemical and natural irrigant solutions on microhardness of root dentin – an in vitro study

Brazilian Journal of Oral Sciences ◽

10.20396/bjos.v17i0.8654060 ◽

2018 ◽

Vol 17 ◽

pp. e18409

Author(s):

Caren Taffarel ◽

Fernanda Duda Bonatto ◽

Filipe do Carmo Bonfante ◽

Huriel Scartazzini Palhano ◽

Cristina de Mattos Pimenta Vidal ◽

...

Keyword(s):

Root Canal ◽

In Vitro Study ◽

Acrylic Resin ◽

Grape Seed ◽

Control Group ◽

Calcium Hypochlorite ◽

Significance Level ◽

Root Canal Irrigants ◽

Root Dentin

Introduction: Modifications in the mechanical properties of dentin may reduce the fracture resistance of tooth, especially after endodontic treatment. The aim of present study was to evaluate the effect of the irrigation with different root canal irrigants on the microhardness of root dentin. Methods: The coronal portion of 60 single-rooted bovine incisors was sectioned and the pulpal tissue removed using endodontic K-files. The roots were cut transversely to obtain 2 fragments, which were embedded in acrylic resin and randomly distributed into six groups (n=20) according to the irrigation protocol: distilled water (DW) (control); 2% chlorhexidine solution (CHX); 6% sodium hypochlorite (NaOCl); 6% calcium hypochlorite (Ca[OCl]2); QMix; and 6.5% grape seed extract solution (GSE). The solutions were kept in contact with the root dentin specimens for 30 min. After that, irrigation with 5 mL of DW was performed. The Vickers microhardness was determined by performing three indentations in all specimens, using 300-g load and 20-second dwell time. The first indentation was made 1.000 µm from the root canal entrance, and two other indentations were made at a distance of 200 µm from each other. The microhardness value for each specimen was obtained as the average of the results for the three indentations. Data were statistically analyzed using one-way ANOVA with 5% significance level. Results: All the tested irrigant solutions maintained the same microhardness level of the root dentin when compared to the control group, with no statistically significant differences between them (p<0.05) Conclusion: The tested irrigant solutions did not present ability to modify the microhardness of root dentin.

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Comparative Study to Evaluate the Surface Detail Reproduction of Dental Stone after Immersion in Various Different Disinfectant Solutions, Under Stereomicroscope 10 X Magnification –An In-Vitro Study

International Journal of Pharmaceutical and Clinical Research ◽

10.25258/ijpcr.v9i3.8316 ◽

2017 ◽

Vol 9 (3) ◽

Author(s):

Rathika Rai ◽

M. A. Easwaran ◽

K. T. Dhivya

Keyword(s):

Sodium Hypochlorite ◽

In Vitro Study ◽

Control Group ◽

Immersion Method ◽

Significant Difference ◽

Surface Irregularities ◽

Disinfectant Solution ◽

Surface Detail ◽

Group B

Aim: To evaluate the surface detail reproduction of dental stone this is immersed in different disinfectant solution and studied under stereomicroscope. Methodology: Total number of 30 specimens of dental stone (Type III) were made with measurements of 1.5cm diameter and 1cm height .This samples are divided in to 3 groups group A,B,C. were A is immersed in Distilled water which was taken as control group ;B is immersed in 2% Glutaraldehyde and C is immersed in 5%sodium hypochlorite. Each specimen were immersed in the disinfectant solution for 15 minutes and dried under room temperature for 24 hrs. After 24 hrs each specimens are studied under stereomicroscope for surface details. Result: The results showed no significant difference in the surface irregularities and porosities for a group 1 and group 2 except group 3 which showed significant increase in the porosities, surface irregularities and erosions after disinfection with 5% NaHOCl by immersion method. Conclusion: The surface detail reproduction capacity of die stone was adversely affected when 5% Sodium hypochlorite was used as disinfectant solution when compare d to control group and 2% Glutaraldehyde

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In vitro study of human osteoblast proliferation and morphology on orthodontic mini-implants

The Angle Orthodontist ◽

10.2319/100714-717.1 ◽

2015 ◽

Vol 85 (6) ◽

pp. 920-926 ◽

Cited By ~ 2

Author(s):

Ricardo Carvalho Bueno ◽

Roberta Tarkany Basting

Keyword(s):

Chemical Composition ◽

In Vitro Study ◽

Chemical Components ◽

Control Group ◽

Osteoblast Proliferation ◽

Mini Implants ◽

Significant Difference ◽

Implant Anchorage ◽

Positive Effect

ABSTRACT Objective: To evaluate the proliferation and morphology of human osteoblasts cultured on two brands of mini-implants after 24, 48, and 72 hours, in addition to the chemical composition found on their surface. Materials and Methods: Two brands of mini-implant (Morelli and Neodent) were evaluated; polystyrene was used as a control group (n = 3). Osteoblasts were cultured on the surface of sterilized mini-implants in a CO2 incubator at different time periods (24, 48, and 72 hours). Osteoblast proliferation was quantified by scanning electron microscopy using up to 5000× magnification, and cell morphology was analyzed by a single observer. For the chemical analysis, spectroscopy X-ray fluorescence was used to identify and quantify chemical components on the surface of the mini-implants. Results: Two-way ANOVA showed no significant interaction between the factors studied (P = 0.686). A Tukey test revealed no significant difference in osteoblast proliferation between the mini-implants at all studied periods; however, a difference in cell proliferation was detected between the Neodent and the control group (P = .025). For all groups, time had a direct and positive effect on osteoblast proliferation (P < .001). The significant elements present in both brands of mini-implants were titanium, aluminum, vanadium, and iron. Conclusions: Osteoblast proliferation was present on the mini-implants studied, which increased over time; however, no significant difference between brands was observed. No difference was seen between the mini-implants evaluated in terms of chemical composition. Cell adhesion after 72 hours suggests that areas of bone remodeling can be achieved, thus initiating the process of mini-implant anchorage.

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The Effect of the Bioactive Glass and the Er:YAG Laser on the Remineralization of the Affected Dentin: A Comparative In Vitro Study

Journal of lasers in medical sciences ◽

10.34172/jlms.2020.27 ◽

2020 ◽

Vol 11 (2) ◽

pp. 160-166

Author(s):

Mohammad Javad Moghaddas ◽

Horieh Moosavi ◽

Sara Yaghoubirad ◽

Nasim Chiniforush

Keyword(s):

Bioactive Glass ◽

In Vitro Study ◽

Control Group ◽

Dentinal Tubule ◽

Glass Ionomer ◽

Significant Difference ◽

Post Hoc ◽

Caries Lesions ◽

Cavity Floor

Introduction: The purpose of this study was to compare the effect of the bioactive glass, the glass ionomer, and the Erbium YAG laser as liners on the remineralization of the affected dentin. Methods: The present study was conducted on 64 healthy extracted human molars divided into 4 groups, 1 control group and 3 experimental groups. After artificially inducing dentinal caries lesions, each of the experimental groups was applied to the cavity floor and then restored with a composite. The samples were stored after thermocycling in an incubator for two months. Finally, the hardness of the cavity floor was measured at 3 depths of 20, 50 and 100 μm by the Vickers microhardness tester. The dentin conditions underneath the liners were also evaluated with FESEM. Statistical analysis was performed by two-way ANOVA and the post-hoc Games-Howell test (P<0.05). Results: Among the groups, the lowest microhardness value was in the control group (P<0.05) except at a depth of 100 μm; therefore, there was no significant difference between the control group and the bioactive glass (P>0.05). The laser group had the highest microhardness value, which was significantly different from the control group (P<0.05). There was a significant difference between the laser and bioactive glass (P<0.05), except at a depth of 20 μm. The laser and glass ionomer had only a significant difference at a depth of 100 μm (P<0.05). The microhardness value induced by glass ionomer was higher than bioactive glass, which in no depth was significant (P>0.05). Partial dentinal tubule occlusion was observed with FESEM in each of the experimental groups as compared to the control group. Conclusion: The microhardness values were higher in all groups than in the control group. The laser might be more successful in remineralization than the other ones.

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Milled versus moulded mock-ups based on the superimposition of 3D meshes from digital oral impressions: a comparative in vitro study in the aesthetic area

BMC Oral Health ◽

10.1186/s12903-019-0922-2 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 14

Author(s):

Francesca Cattoni ◽

Giulia Teté ◽

Alessandro Mauro Calloni ◽

Fabio Manazza ◽

Giorgio Gastaldi ◽

...

Keyword(s):

Statistical Analysis ◽

Test Group ◽

In Vitro Study ◽

Mean Value ◽

Digital Impression ◽

Control Group ◽

Minimal Invasiveness ◽

Significant Difference ◽

The Aesthetic

Abstract Background Aesthetic porcelain veneers proved to be a long-term reliable prosthetic solution, ensuring minimal invasiveness. The use of veneers requires an adhesive cementation technique, so maintaining as much enamel as possible is to ensure lasting success. A diagnostic mock-up is a key tool that allows a preview of the outcome of the aesthetic restoration: it is obtainable both in an analog and digital way. With the recent developments in impression technology and the ever so fast growing use of CAD-CAM technologies it is useful to understand the pros and cons of either one of these techniques (analog and digital) in order to identify the easier and more convenient workflow in aesthetic dentistry. Methods After taking pictures and impressions of the dental arcs of a patient in need of aesthetic rehabilitation, 52 resin models were produced and a digital drawing of the smile was outlined. Both an analog and a digital wax-up were obtained from two of the 52 models: the latter was obtained using digital impressions and a dedicated software. The analog wax-up was then used to produce 25 matrices that have later been used to mould 25 resin mock-ups using a traditional moulding protocol (Control Group - CG). The digital wax-up was used to mill 25 PMMA mock-ups. Each mock-up, both milled and moulded (total 50), was then laid on the other 50 resin models as a digital impression of it was taken. The STL. files of the milled mock-ups were compared with the 3D CAD wax-up made using a specific software. The STL. files of the analog printed mock-ups were compared with the traditional wax-up design. A statistical analysis was carried out to evaluate the difference between the groups. Results The statistical analysis showed a significant difference (P > 0.01) between the mean value of the distance between the points of the overlapping STL. meshes in GC (0.0468 mm) and in TG (Test Group - TG) (0,0109 mm). Conclusions The study showed a difference in accuracy between traditional moulded and milled mock-ups compared to their original wax-up. The data analysis reports that the digital method allows for greater accuracy. Within the limitations of this study, a fully digital workflow is to considered more reliable when it come to creating an esthetic mockup: the digital procedure has been shown to be more accurate than the one made manually which is much more operator dependent and it brings an increase to the chance of error, and that could ultimately affect the final result.

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Effect of Gamma Radiation and Endodontic Treatment on Mechanical Properties of Human and Bovine Root Dentin

Brazilian Dental Journal ◽

10.1590/0103-6440201601267 ◽

2016 ◽

Vol 27 (6) ◽

pp. 670-674 ◽

Cited By ~ 6

Author(s):

Veridiana Resende Novais ◽

Priscilla Barbosa Ferreira Soares ◽

Carlla Martins Guimarães ◽

Laís Rani Sales Oliveira Schliebe ◽

Stella Sueli Lourenço Braga ◽

...

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Gamma Radiation ◽

Hardness Test ◽

Knoop Hardness ◽

Endodontic Treatment ◽

Bending Test ◽

Human Teeth ◽

Significant Difference ◽

Root Dentin

Abstract This study evaluated the effect of gamma radiation and endodontic treatment on the microhardness and flexural strength of human and bovine root dentin. Forty single-rooted human teeth and forty bovine incisor teeth were collected, cleaned and stored in distilled water at 4 °C. The human and bovine teeth were divided into 4 groups (n=10) resulting from the combination of two study factors: first, regarding the endodontic treatment in 2 levels: with or without endodontic treatment; and second, radiotherapy in two levels: with or without radiotherapy by 60 Gy of Co-60 gamma radiation fractioned into 2 Gy daily doses five days per week. Each tooth was longitudinally sectioned in two parts; one-half was used for the three-point bending test and the other for the Knoop hardness test (KHN). Data were analyzed by 3-way ANOVA and Tukey HSD test (α=0.05). No significant difference was found for flexural strength values. The human dentin had significantly higher KHN than the bovine. The endodontic treatment and radiotherapy resulted in significantly lower KHN irrespective of tooth origin. The results indicated that the radiotherapy had deleterious effects on the microhardness of human and bovine dentin and this effect is increased by the interaction with endodontic therapy. The endodontic treatment adds additional negative effect on the mechanical properties of radiated tooth dentin; the restorative protocols should be designed taking into account this effect.

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

Brazilian Dental Science ◽

10.14295/bds.2020.v23i3.1895 ◽

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

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Influence of Exposing Root Canal Dentin to Calcium Hydroxide on Its Flexural Strength

The Indonesian Journal of Dental Research ◽

10.22146/theindjdentres.10063 ◽

2015 ◽

Vol 1 (3) ◽

pp. 143

Author(s):

Diatri Nari Ratih

Keyword(s):

Flexural Strength ◽

Calcium Hydroxide ◽

Root Canal ◽

Artificial Saliva ◽

Testing Machine ◽

In Vitro Study ◽

Control Group ◽

Sterile Saline ◽

Root Canal Dentin

Calcium hydroxide has been used extensively in endodontic treatments, for instance as an intra-canal dressing; however, the exposure of root canal dentin to calcium hydroxide may affect its flexural strength and could have important clinical implications for endodontic treatment. The purpose of this in vitro study was to investigate the influence of calcium hydroxide on the flexural strength of root canal dentin.Seventy-two extracted single-rooted human mandibular premolars were used in this study. Each tooth was instrumented using crown-down technique and was irrigated using sterile saline. The teeth were assigned into three groups of 24 each. The prepared root canal system of each tooth was filled with calcium hydroxide mixed with sterile saline (group 1), a calcium hydroxide commercially available product (UltraCal®) (group 2) or saline solution (group 3, as control). The apices and access opening were sealed using composite resin, and the teeth were immersed in artificial saliva. After 7, 14 and 30 days of immersion, the inner root canal dentin of 8 teeth respectively from each group were sectioned to create dentin bars (1 X 1 mm, with 7 mm in length). Each dentin bar then was subjected to a three-point bending flexural test using MTS (Universal Testing Machine). Data gathered were then analyzed using two-way ANOVA, followed by Tukey’s test with the level of significance of 95%. The results showed that exposure to calcium hydroxide either using calcium hydroxide mixed with sterile saline or UltraCal® for 14 and 30 days can reduce flexural strength of root canal dentin compared to control group (p<0.05). In contrast, after 7 days exposure, there was no significantly different of flexural strength between three groups (p>0.05). It can be concluded that calcium hydroxide reduced the flexural strength of root canal dentin. The longer the exposure to calcium hydroxide would produce a greater effect on flexural strength of root canal dentin.

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Comparative Evaluation of Physical and Mechanical Properties of Different Brands of Primary Molar Stainless-Steel Crowns: An In Vitro Study

Open Access Macedonian Journal of Medical Sciences ◽

10.3889/oamjms.2019.861 ◽

2019 ◽

Vol 7 (23) ◽

pp. 4120-4126

Author(s):

Zhaleh Bamdadian ◽

Nilgoon Pasdar ◽

Abdolhamid Alhavaz ◽

Shahram Ghasemi ◽

Ali Bijani

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Fatigue Strength ◽

Galvanic Corrosion ◽

Physical And Mechanical Properties ◽

In Vitro Study ◽

Vitro Study ◽

Primary Molar ◽

Significant Difference

BACKGROUND: There is some cases of perforation and undesirable properties of some primary molars stainless steel crowns. AIM: The aim of this study was to compare the physical and mechanical properties of different commercial brands of these crowns. METHODS: In an in vitro study, a total of 10 stainless steel tooth crowns of the second primary mandibular molars size 6 of 4 different commercial brands (a total of 280 crowns) were evaluated. These crowns were included KTR Pre-trimmed and Crimped Nichro Stainless Steel Primary Molar Crowns (KTR, China); 3M Stainless Steel Primary Molar Crowns (ESPE, St paul; USA); NuSmile SSC Pre-contoured (Inc, Houstone, TX; USA) and Kids crown (Shinghung, Seoul; Korea). Corrosion and galvanic corrosion, wear, microhardness, compressive strength, fatigue strength of crowns and weight percent of elements were investigated. RESULTS: The highest rate of microhardness, compressive and Fatigue strength of the crowns were made by Nu Smile > 3M > Kids Crown > KTR respectively. The highest rate of corrosion potential in corrosion and Galvanic corrosion tests was in KTR > Kids crowns > 3M > Nu smile respectively. The order of crown wear was KTR > Kids Crown > 3M > Nu Smile respectively. The highest amount of nickel element was found in the Nu Smile crown and the highest amount of chrome in the 3M crown with a significant difference with others (p < 0.001). The KTR and Kids crowns lacked molybdenum. CONCLUSION: The results showed that Nu Smile crown has better physical and mechanical properties than other evaluated crowns in this study.

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