THE EFFECT OF COMPOSITION CHANGE IN SOL-GEL SYNTHESIZED PSC

2008 ◽  
Vol 20 (01) ◽  
pp. 53-59
Author(s):  
Wen-Hsi Wang ◽  
Yuan-Ling Lee ◽  
Chun-Pin Lin ◽  
Feng-Huei Lin

Modified calcium silicate cement had previously been developed as a dental retrograde filling. It had great sealing ability, good biocompatibility, and anti-bacterial properties. However, its clinical application was limited by a long setting time and poor handling property. In previous study,1, 2 the setting property of PSC was greatly improved due the sol-gel process, without the addition of transition metal element. In this study, different ratio of starting material of PSC was prepared. The composition of each group was also altered with the ratio of the starting materials according to the result of XRD pattern. There is no significant difference in pH variation profile between each group. Even though low C 3 S / C 4 AF ratio (DX631 and DX541 groups) possessed high initial strength at first 24 hours after hydration, there was no increase in strength ever since according to the result of microhardness. However, the groups with high C 3 S / C 4 AF ratio (DX811 and DX721 groups) possessed relatively low initial strength at 24 hours after hydration, but the strength increased rapidly and continuously at least for the next six days of hydration. Moreover, the peak intensity of hydration product (Portlandite) on XRD pattern in DX811 group was much higher than other three groups, and this was also in agreement with the result of microhardness. DX811 group is determined to be the optimal one for the further development in the application as root-end filling materials.

2020 ◽  
Author(s):  
Manisha Nepal ◽  
Snigdha Shubham ◽  
Rupam Tripathi ◽  
Jwolan Khadka ◽  
Deepa Kunwar ◽  
...  

Abstract Background The present study compares the apical microleakage of three different root-end filling materials in which the retrograde cavity is prepared by two different burs. Methods Eighty extracted single rooted maxillary and mandibular premolars were taken. Root canal treatment was completed. Apical 3 mm of all the teeth were resected with diamond disk. The tooth were divided into four groups with two subgroups for each group containing 10 tooth (N= 10) as: Group IA (Negative Control and IB (Positive Control); Group IIA and IIB: Prepared with round carbide bur and round diamond bur respectively, filled with GIC; Group IIIA and IIIB: Prepared with round carbide bur and round diamond bur respectively, filled with MTA; Group IVA and IVB: Prepared with round carbide bur and round diamond bur, filled with Biodentine. After applying two coats of nail varnish leaving apical 3 mm (except for negative control group) all teeth were immersed in 2% methylene blue for 3 days and again in 65% nitric acid for next 3 days for extraction of dye. The obtained solution was then transferred to eppendorf tube and centrifuged in microcentrifuges at 14,000 revolution per minutes (RPM) for 5 minutes. Optical density or absorbance of the supernatant solution was measured with UV spectrophotometer at 550 nm. Results The absorbance of the supernatant solution after dye extraction is decreasing in the order of positive control> GIC> MTA> Biodentine> negative control group. The significant difference was observed between GIC and MTA (p=0.0001) and GIC and Biodentine (p=0.0001) with two different burs but statistically non-significant difference was observed between MTA and Biodentine with Carbide bur (p=0.127) and Diamond bur (p=0.496) respectively. Conclusions Within the limitations of the present study, it can be concluded that Biodentine and MTA showed less microleakage as compared to GIC. There is no significant difference between mean microleakage of MTA and Biodentine. However, the mean OD of the Biodentine was least of all evaluated materials. Preparation of the root-end using round carbide bur as well as round diamond burs showed comparable microleakage for all three filling materials.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
D. Regonini ◽  
A. K. Alves ◽  
F. A. Berutti ◽  
F. Clemens

This work has focused on the investigation of a non-aqueous based sol-gel process to produce TiO2based photoelectrodes for solar water splitting. In particular, the effect of the aging time of the sol and TiO2film thickness on the photoelectrochemical properties of the photoanodes has been investigated. In order to achieve optimal performances (i.e., photocurrent density up to 570 µA/cm2and IPCE of 26% at 300 nm), the sol needs to be aged for 3 to 6 h, before being dip-coated to produce the photoanodes. The importance of the aging time can also be appreciated from the optical properties of the TiO2films; the absorbance threshold of the sol-gel aged for 3–6 h is slightly shifted towards longer wavelenghts in comparison to 0 h aging. Aging is necessary to build up a well-interconnected sol-gel network which finally leads to a photoelectrode with optimized light absorption and electron collection properties. This is also confirmed by the higher IPCE signal of aged photoelectrodes, especially below 340 nm. Among thicknesses considered, there is no apparent significant difference in the photoresponse (photocurrent density and IPCE) of the TiO2sol-gel films.


2020 ◽  
Author(s):  
Manisha Nepal ◽  
Snigdha Shubham ◽  
Rupam Tripathi ◽  
Jwolan Khadka ◽  
Deepa Kunwar ◽  
...  

Abstract Background The present study compares the apical microleakage of three different root-end filling materials in which the retrograde cavity is prepared by two different burs.Methods Eighty extracted single rooted maxillary and mandibular premolars were taken. Root canal treatment was completed. Apical 3 mm of all the teeth were resected with diamond disk. The tooth were divided into four groups with two subgroups for each group containing 10 tooth (N= 10) as: Group IA (Negative Control and IB (Positive Control); Group IIA and IIB: Prepared with round carbide bur and round diamond bur respectively, filled with GIC; Group IIIA and IIIB: Prepared with round carbide bur and round diamond bur respectively, filled with MTA; Group IVA and IVB: Prepared with round carbide bur and round diamond bur, filled with Biodentine. After applying two coats of nail varnish leaving apical 3 mm (except for negative control group) all teeth were immersed in 2% methylene blue for 3 days and again in 65% nitric acid for next 3 days for extraction of dye. The obtained solution was then transferred to eppendorf tube and centrifuged in microcentrifuges at 14,000 revolution per minutes (RPM) for 5 minutes. Optical density or absorbance of the supernatant solution was measured with UV spectrophotometer at 550 nm.esults The absorbance of the supernatant solution after dye extraction is decreasing in the order of positive control> GIC> MTA> Biodentine> negative control group. The significant difference was observed between GIC and MTA (p=0.0001) and GIC and Biodentine (p=0.0001) with two different burs but statistically non-significant difference was observed between MTA and Biodentine with Carbide bur (p=0.127) and Diamond bur (p=0.496) respectively.Conclusions Within the limitations of the present study, it can be concluded that Biodentine and MTA showed less microleakage as compared to GIC. There is no significant difference between mean microleakage of MTA and Biodentine. However, the mean OD of the Biodentine was least of all evaluated materials. Preparation of the root-end using round carbide bur as well as round diamond burs showed comparable microleakage for all three filling materials.


2016 ◽  
Vol 27 (2) ◽  
pp. 196-201 ◽  
Author(s):  
Raquel Assed Bezerra Segato ◽  
Carolina Maschietto Pucinelli ◽  
Danielly Cunha Araújo Ferreira ◽  
Andiara De Rossi Daldegan ◽  
Roberto S. da Silva ◽  
...  

Abstract This study evaluated physiochemical proprieties of a calcium hydroxide-based paste (Calen(r)) combined with a zinc oxide cement at different ratios (1:0.5, 1:0.65, 1:0.8 and 1:1). Materials were compared regarding setting time, pH variation, radiopacity, solubility, dimensional changes, flow and release of chemical elements. Data were analyzed statistically by ANOVA and Tukey's test (α=0.05). Longer setting time and higher dimensional changes and solubility values were exhibited by 1:0.65 and 1:0.5 ratios (p<0.05). The 1:0.5 and 1:0.65 ratios exhibited the highest pH values at all time points. All materials exhibited high radiopacity values. Significant differences were found only between 1:0.5 and 1:1 ratios for calcium and zinc release (p<0.05), whereas the amount of zirconium was similar among all groups (p>0.05). Considering the evaluated proprieties, combinations of Calen(r) paste with ZO at 1:0.5 and 1:0.65 ratios had the best results as root canal filling materials for use in primary teeth.


2021 ◽  
Vol 25 (3) ◽  
pp. 159-165
Author(s):  
Merve Mutluay ◽  
Abidin Talha Mutluay

Summary Background/Aim: This in-vitro study evaluated the apical-sealing ability of MTA, MTA+10% CaCl2, Biodentine™ and RMGIC when used as retrograde material. Material and Methods: A total of 80 single-rooted bovine incisors were decoronated, instrumented, and divided into 4 groups according to retrograde material, as follows: Group 1: MTA (ProRoot MTA, Dentsply); Group 2: MTA (ProRoot MTA, Dentsply) + 10% CaCl2; Group 3: Biodentine (Biodentine®, Septodont); Group 4: RMGIC (Nova Glass -LC, Imicryl). Root surfaces were isolated with nail polish, and teeth were immersed in 2% methylene blue dye at 37°C for 48 h. The extent of dye penetration (mm) was measured under a stereomicroscope. Results: RMGIC had the highest mean-rank dye penetration score (MP=49.05), followed by MTA (MP=43.65), Biodentine (35.95) and MTA+CaCl2 (MP=33.35). The results of paired comparison tests found the mean microleakage value of MTA+10% CaCl2 and Biodentine (Group 3) to be significantly lower than that of RMGIC (respectively; p=0,020, p=0,019). No significant difference was found in the other group comparisons (p> 0.05). Conclusions: These results suggest that the addition of an accelerator to MTA may reduce microleakage following endodontic surgery. Biodentine can be used as an alternative to MTA on retrograde obturation.


2019 ◽  
Author(s):  
Manisha Nepal ◽  
Snigdha Shubham ◽  
Rupam Tripathi ◽  
Jwolan Khadka ◽  
Deepa Kunwar

Abstract Background The present study compares the apical microleakage of three different root-end filling materials in which the retrograde cavity is prepared by two different burs.Methods Eighty extracted single rooted maxillary and mandibular premolars were taken. Root canal treatment was completed. Apical 3 mm of all the teeth were resected with diamond disk. The tooth were divided into four groups with two subgroups for each group containing 10 tooth (N= 10) as: Group IA (Negative Control and IB (Positive Control); Group IIA and IIB: Prepared with round carbide bur and round diamond bur respectively, filled with GIC; Group IIIA and IIIB: Prepared with round carbide bur and round diamond bur respectively, filled with MTA; Group IVA and IVB: Prepared with round carbide bur and round diamond bur, filled with Biodentine. After applying two coats of nail varnish leaving apical 3 mm (except for negative control group) all teeth were immersed in 2% methylene blue for 3 days and again in 65% nitric acid for next 3 days for extraction of dye. The obtained solution was then transferred to eppendorf tube and centrifuged in microcentrifuges at 14,000 revolution per minutes (RPM) for 5 minutes. Optical density or absorbance of the supernatant solution was measured with UV spectrophotometer at 550 nm.Results The absorbance of the supernatant solution after dye extraction is decreasing in the order of positive control> GIC> MTA> Biodentine> negative control group. The significant difference was observed between GIC and MTA (p=0.0001) and GIC and Biodentine (p=0.0001) with two different burs but statistically non-significant difference was observed between MTA and Biodentine with Carbide bur (p=0.127) and Diamond bur (p=0.496) respectively.Conclusions Within the limitations of the present study, it can be concluded that Biodentine and MTA showed less microleakage as compared to GIC. There is no significant difference between mean microleakage of MTA and Biodentine. However, the mean OD of the Biodentine was least of all evaluated materials. Preparation of the root-end using round carbide bur as well as round diamond burs showed comparable microleakage for all three filling materials.


2016 ◽  
Vol 683 ◽  
pp. 318-324 ◽  
Author(s):  
Anna Nikolaevna Grishina ◽  
Evgeniy Valerjevich Korolev

The present work is devoted to the examination of new radiation-protective binder for special-purpose composite materials. The mixture for such advanced binder is developed. The mixture includes portland cement together with special component – barium hydrosilicates. The latter are micro-sized mineral admixtures which are synthesized by means of low-temperature sol-gel process. The parameters of early structure forming process (including normal density and setting time) are studied. Mechanical properties of the developed binders are determined. It has been shown that admixture of barium hydrosilicates leads to an increase of normal density. Both low and high setting times are reducing for composite binder with barium hydrosilicates. Values of compressive strength are significantly higher (up to 75%) if compared with traditional binder for radiation-protective building materials. It is also revealed during examination of protective properties that for X-ray photons with energy Eγ = 0.1 MeV linear coefficient of attenuation increases by 80%.


Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1693
Author(s):  
Tae-Yun Kang ◽  
Ji-Won Choi ◽  
Kyoung-Jin Seo ◽  
Kwang-Mahn Kim ◽  
Jae-Sung Kwon

Commercial mineral trioxide aggregate (MTA) materials such as Endocem MTA (EC), Dia-Root Bio MTA (DR), RetroMTA (RM), and ProRoot MTA (PR) are increasingly used as root-end filling materials. The aim of this study was to assess and compare the physicochemical and mechanical properties and cytotoxicity of these MTAs. The film thicknesses of EC and DR were considerably less than that of PR; however, RM’s film thickness was greater than that of PR. In addition, the setting times of EC, DR, and RM were shorter than that of PR (p < 0.05). The solubility was not significantly different among all groups. The three relatively new MTA groups (EC, DR, and RM) exhibited a significant difference in pH variation and calcium ion release relative to the PR group (p < 0.05). The radiopacity of the three new MTAs was considerably less than that of PR. The mechanical strength of RM was not significantly different from that of PR (p > 0.05); however, the EC and DR groups were not as strong as PR (p < 0.05). All MTA groups revealed cytocompatibility. In conclusion, the results of this study confirmed that EC, RM, DR, and PR exhibit clinically acceptable physicochemical and mechanical properties and cell cytotoxicity.


Author(s):  
J.M. Schwartz ◽  
L.F. Francis ◽  
L.D. Schmidt ◽  
P.S. Schabes-Retchkiman

Ceramic thin films and coatings are of interest for electrical, optical, magnetic and thermal barrier applications. Critical for improved properties in thin films is the development of specific microstructures during processing. To this end, the sol-gel method is advantageous as a versatile processing route. The sol-gel process involves depositing a solution containing metalorganic or colloidal ceramic precursors onto a substrate and heating the deposited layer to form a crystalline or non-crystalline ceramic coating. This route has several advantages, including the ability to create tailored microstructures and properties, to coat large or small areas, simple or complex shapes, and to more easily prepare multicomponent ceramics. Sol-gel derived coatings are amorphous in the as-deposited state and develop their crystalline structure and microstructure during heat-treatment. We are particularly interested in studying the amorphous to crystalline transformation, because many key features of the microstructure such as grain size and grain size distribution may be linked to this transformation.


1999 ◽  
Vol 606 ◽  
Author(s):  
Keishi Nishio ◽  
Jirawat Thongrueng ◽  
Yuichi Watanabe ◽  
Toshio Tsuchiya

AbstructWe succeeded in the preparation of strontium-barium niobate (Sr0.3Ba0.7Nb2O6 : SBN30)that have a tetragonal tungsten bronze type structure thin films on SrTiO3 (100), STO, or La doped SrTiO3 (100), LSTO, single crystal substrates by a spin coating process. LSTO substrate can be used for electrode. A homogeneous coating solution was prepared with Sr and Ba acetates and Nb(OEt)5 as raw materials, and acetic acid and diethylene glycol monomethyl ether as solvents. The coating thin films were sintered at temperature from 700 to 1000°C for 10 min in air. It was confirmed that the thin films on STO substrate sintered above 700°C were in the epitaxial growth because the 16 diffraction spots were observed on the pole figure using (121) reflection. The <130> and <310> direction of the thin film on STO were oriented with the c-axis in parallel to the substrate surface. However, the diffraction spots of thin film on LSTO substrate sintered at 700°C were corresponds to the expected pattern for (110).


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