Physical Properties Of Dental Materials Research Articles

Evaluation of mechanical properties of fluoride-releasing dental materials after multiple fluoride recharge/discharge application

This study aimed to determine the mechanical properties of fluoride-releasing dental materials after an accelerated fluoride recharge/discharge procedure. Two fluoride-releasing glass ionomer types of cement (Ketac Molar Easymix and IonoStar Molar), a resin-modified glass ionomer (Photac Fil Quick Aplicap), and two compomers (Compoglass F and Glasiosite) were used in this study. A total of 30 rectangular specimens and 30 disk specimens of each material were prepared and placed in distilled/deionized water (n = 5). The amount of fluoride released was analyzed from the materials for 7-day discharge, 1st recharge, 7-day discharge, 2nd recharge, and 7-day discharge, and 3rd recharge. The de/pre- and post-recharge fluoride release were measured using an ion chromatography for 24 days. The flexural strength and microhardness of each group were evaluated. The microhardness of all restorative materials showed no significant change (p > 0.05) over the experimental period. The flexural strength properties of the restorative materials did not change within the time of the study. The study showed that the fluoride release/uptake causes no effect on the mechanical and physical properties of dental materials.

Experimental synthesis of size-controlled TiO2 nanofillers and their possible use as composites in restorative dentistry

The aim of this work was to obtain an efficient protocol with a green, fast and facile way to synthesize TiO2 NPs and its application as fillers for enhancement of desired dental properties of light curing dental composites.A comparative study comprised the fabrication of light curing restorative composite materials with incorporating different fillers with varying wt%, varying resin material composition, to determine optimal dental restoration by focusing on the physical properties of dental materials. It was observed that the as-prepared green synthesized TiO2 nanohybrid particles contributed to the improvement in physical properties, thus promoting the green and rapid synthesis of nanohybrid fillers. In addition, mechanical values for experimental cured resin materials with bare and surface modified fillers were obtained. The experimental light curing nanocomposites with 5 wt% (wt%) nanohybrid surface modified filler particles with BisGMA (60 wt%), TEGDMA (20 wt%) and UDMA (20 wt%) resin composition provided increased physical strength and durability with higher compressive stress 195.56 MPa and flexural stress 83.30 MPa. Furthermore, the dental property, such as polymerization shrinkage (PS) obtained from volumetric method was decreased up to 3.4% by the addition of nano-hybrid fillers. In addition to this, the biocompatible and antimicrobial nature of TiO2 and its aesthetics properties such as tooth-like color makes TiO2 favorable to use as fillers.This study presents a green and facile method for the synthesis of TiO2 nanohybrid particles that can be successfully used as fillers in an experimental light curing resin matrix for enhancing its dental properties. This describes the potential of the green synthesized TiO2 nanohybrid particles to use as fillers in restorative dentistry.

ORAL MUCOSA DAMAGE BECAUSE OF HYPOCHLORITE ACCIDENT – A CASE REPORT AND LITERATURE REVIEW

Background Hypochlorite solution is widely used in dental practice during root canal treatment. Although it is generally regarded as being very safe, potentially severe complications can occur when it comes into contact with soft tissue especially due to its cytotoxic features. Objective The aim of our paper is to present a case of damage of oral mucosa because of leakage of 3% hypochlorite through rubber dam during endodontic treatment. Material and methods We present a 31 years old female with necrosis of buccal mucosa during the endodontic treatment of 46. Results Three days after the procedure the patient was referred to our department for consultation and treatment. Antiseptic lavage was performed and oral antibiotic was administrated. After 5 days intraoral examination showed signs of almost full recovery. Conclusion The need for proper tooth isolation during restorative procedures is obvious. Anything that obscures the operative field negatively impacts operator efficiency and effectiveness. Visibility, patient/operator safety, infection control and the physical properties of dental materials are all compromised when proper isolation is lacking.

Effects of Different Temperatures and Storage Time on the Degree of Conversion and Microhardness of Resin-based Composites.

Dental materials are often made at room temperature, whereas clinically they are made in the mouth. This study evaluated the effects of temperature on the degree of conversion (DC) and Knoop microhardness (KHN). Two types of resin-based composites (RBCs) were light-cured using a light-emitting diode (LED) light-curing unit. The resin specimens were centered on an Attenuated Total Reflectance Fourier transform infrared (FT-IR) plate heated to 23°C or 33°C. The DC of the resin was calculated after 120 seconds, the specimens were removed, and the KHN was tested at the bottom of the specimens both immediately, after 24 hours, and after 7 days storage in distilled water in complete darkness at 37°C. The effects of different temperatures on the DC and KHN with their storage time were compared by analysis of variance and Fisher's protected least significant difference post hoc multiple comparison tests (p < 0.05). Increasing the temperature had a significant and positive effect on the DC and KHN for immediate values of the RBCs. Greater conversion and hardness occurred when the curing temperature was increased from 23°C to 33°C. The KHN increased significantly after 24 hours of storage. There was a linear relationship between DC and KHN (R(2) = 0.86) within the range of DC and KHN studied. The physical properties of dental materials can be expected to be better when made in the mouth than when they are made in a laboratory at room temperature.

Euro BioMat 2011

Dear Readers of Advanced Biomaterials, On 13th and 14th of April 2011, the first Euro BioMat European Symposium on Biomaterials and Related Areas took place in Jena, Germany. With a new format, the symposium Euro BioMat 2011 addressed the growing interest of colleagues from science and industry in the different aspects of biomaterials including the creation, characterization, testing and application of biomaterials, and closely related areas, such as biomimetics, biomineralization, and biopolymers. The organizers and the Deutsche Gesellschaft für Materialkunde (DGM) felt a need to serve the European Biomaterials community beyond existing European and world biomaterials congresses with a compact two-day meeting. Jena is the ideal setting for the Euro Biomat, not only because of its geographic site in the very heart of Europe but also because it is a recognized location for biomedical engineering. The Euro BioMat started with plenary lectures from Marga Lensen (TU Berlin, Germany) and Thomas J. Webster (Brown University, USA) addressing micro- and nanotechnology at biointerfaces and for regenerative medicine, respectively. Since Tom Webster could not be at symposium in person, we witnessed a premiere at the Euro BioMat: Tom gave an excellent and inspiring keynote lecture from Providence in the US to Jena via mobile phone. On the second day of the Euro BioMat, Ivan Martin (University Hospital Basel) presented a plenary lecture about 3D-tissue engineering followed by a second plenary lecture from Willem J. van der Giessen (Erasmus University Medical Center, Netherlands) about latest developments in bioresorbable stents. The topics of the Euro BioMat 2011 included bioinspired materials, bio-nanomaterials, biointerfaces, dental materials, biomaterials/clinical applications, bio-based polymers, tissue engineering/regenerative medicine, antimicrobial biomaterials. A bit of statistics from the Euro BioMat 2011 symposium: 134 orals presentations and 75 posters were presented. 270 delegates from 33 countries participated in the symposium, among these a large number of early stage researchers. With one review, eight full papers, and one rapid communication this special issue of Advanced Biomaterials is a good cross-section of the work presented at the Euro BioMat 2011. Subjects covered in this special issue include the topographical influence on cell adhesion, fibroblasts-engineered spider silk protein interaction, modeling of wound healing processes, new injectable hydrogels for drug delivery, anisotropic physical properties of dental materials, and bio-sintering/bio-fusion of silica. The Euro BioMat 2011 would not have been possible without the support of the Deutsche Forschungsgemeinschaft (DFG) in Bonn, Germany and the excellent organizational support of the DGM, especially Mrs. Anja Mangold. We are grateful to both organizations. The next Euro BioMat will be held in Jena in April 2013 and we are looking forward to welcome you at this symposium. I do hope you enjoy reading this issue of Advanced Biomaterials. Yours faithfully Klaus D. Jandt

The role of torque, torsion, and bending in prosthodontic failures

The effects of torque, torsion, and bending on teeth and the supporting structures were analyzed. The physical properties of dental materials and structures determine the success or failure of dental restorations. All dental structures and materials must be used within their proportional limits of elasticity. Unless the principles of mechanics acceptable to engineering practice are observed in applying and resisting loads on dental fabrications, failure of the foundation is likely. The kinematics of dental restorations determines cavity preparation. Important principles of cavity preparation stem from this study. Unless advantage is taken of this knowledge, failure of the abutments is likely.

Fluid Exchange at the Margins of Dental Restorations

of a thesis presented by Robert B. Wolcott in partial fulfillment of the requirements of the graduate school, Georgetown University, Washington, D. C., for the degree of Master of Science. Publication approved by the Council on Dental Re­ search. Presented before the twenty-ninth general meet­ ing of the International Association for Dental Research, French Lick, Ind., March 17, 1951. The opinions or assertions contained in this article are the private ones of the writer and are not to be construed as official or reflecting the views of the Navy Department or the naval service at large. •Research associate of the American Dental Associa­ tion at the National Bureau of Standards. fCommander. DC, USN, Naval Dental School, N a­ tional Naval Medical Center, Bethesda, Md., stationed at the National Bureau of Standards. 1. Souder, Wilmer, and Paffenbarger, G. C. Physical properties of dental materials. Circular 433 of the Na­ tional Bureau of Standards, Washington, D. C., Govern­ ment Printing Office, 1942, p. 13. 2. Salisbury, G. B. Present status of direct acrylic restorations. D. Digest 56:202 (May) 1950. 3. Meyer, H. t. Matrix retention in Class II I and Class IV acrylic restorations. D. Digest 56:394 (Sept.)

Physical Properties of Dental Materials

Physical Properties of Dental Materials

Changes of Materials and the Technic of Casting With Regard to Accurate Compensation

Changes of Materials and the Technic of Casting With Regard to Accurate Compensation

Physical Properties of Dental Materials (Some Laboratory Experiments for the Dental School)

Physical Properties of Dental Materials (Some Laboratory Experiments for the Dental School)

Physical properties of dental materials (Gold alloys and accessory materials)

Physical properties of dental materials (Gold alloys and accessory materials)

齒科材料ノ物理的性状

齒科材料ノ物理的性状

Physical Properties of Dental Materials

Physical Properties of Dental Materials

Physical Properties of Dental Materials II*

Physical Properties of Dental Materials II*

An investigation of the physical properties of dental materials

An investigation of the physical properties of dental materials