Comparisons of nanoindentation, 3-point bending, and tension tests for orthodontic wires

Iijima, Masahiro; Muguruma, Takeshi; Brantley, William A.; Mizoguchi, Itaru

doi:10.1016/j.ajodo.2009.11.015

Cited by 47 publications

(53 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…There is a strong correlation (0.84<r 2 <0.92) between the microhardness of enamel and the mineral content, as determined by transverse microradiography of carious lesions 19,21) . Although conventional microhardness testing generally results in large indentations (i.e., an indentation length equivalent to a width of 5-20 enamel prisms) and is influenced by the substrate 19) , recent advances in nanoindentation techniques have enabled measurement of the mechanical properties of extremely small volumes of material, and both the hardness and elastic modulus can be determined simultaneously based on load-displacement data at the submicron scale [28][29][30] . Changes in the elastic modulus of enamel may be associated with the brittleness of the structure; thus, investigating the elastic modulus of enamel provides valuable data.…”

Section: Discussionmentioning

confidence: 99%

The effects of single application of pastes containing ion-releasing particles on enamel demineralization

et al. 2017

Self Cite

View full text Add to dashboard Cite

We investigated single application of pastes containing a surface reaction-type pre-reacted glass-ionomer (S-PRG) filler on enamel demineralization. Human enamel blocks were polished using pastes containing S-PRG filler (0, 5, and 30%) and immersed in demineralizing solution for 5 days with daily change of solutions. The pH measurement and nanoindentation testing was carried out during the immersion period, and the enamel surfaces were examined using scanning electron microscopy and atomic force microscopy. A non-fluoride paste and a hydroxyapatite-containing paste were used for comparison. The specimens polished with the S-PRG filler-containing paste exhibited acid-neutralizing properties, which became stronger with an increasing S-PRG filler content. Following immersion in the demineralizing solution, specimens polished with the S-PRG filler-containing paste exhibited significantly greater hardness and elastic modulus values than those polished with the other pastes and exhibited a smoother surface than did the other specimens. Pastes containing S-PRG filler inhibits the demineralization of enamel.

show abstract

Section: Discussionmentioning

confidence: 99%

The effects of single application of pastes containing ion-releasing particles on enamel demineralization

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…The traditional Knoop microhardness test generally produces a large indentation (indentation length equivalent to a width of 5-20 enamel prisms) and is also influenced by the substrate 23) . However, recent advances in nanoindentation tests now allow the measurement of mechanical properties of extremely small volumes of material, and the hardness and elastic modulus can be determined simultaneously [25][26][27][28][29] . In the present study, a depth-dependent analysis of the enamel surface region was performed with an isotropic voxel size of 3.6 µm in µCT scanning images and with a 5-µm interval for indentations in nanoindentation testing.…”

Section: Discussionmentioning

confidence: 99%

Effects of CO<sub>2</sub> laser irradiation combined with fluoride application on the demineralization, mechanical properties, structure, and composition of enamel

et al. 2015

Self Cite

View full text Add to dashboard Cite

We investigated the effects of CO2 laser irradiation combined with acidulated phosphate fluoride (APF) application on the demineralization of enamel. APF gel was applied to the buccal enamel of human premolars and CO2 laser was applied. After the specimens were immersed in demineralization solution for 72 h, they were subjected to depth-dependent micro-CT and nanoindentation analyses. Micro-X-ray diffraction and X-ray photoelectron spectroscopy were performed to analyze the surfaces. Some surface regions of the enamel in specimens that were laser-irradiated with low output and APF-treated showed significantly higher values of MD and hardness than specimens treated with APF alone. A higher fluoride concentration in the enamel surface was observed in specimens treated with CO2 laser irradiation plus APF gel application. In conclusion, CO2 laser irradiation with low output is preferable to improve acid resistance.

show abstract

“…1000 nm depth analysis (n = 10). Linear extrapolation methods (ISO Standard 14577) were used for the unloading curve between 95% and 70% of the maximum test force to calculate the elastic modulus [30][31][32][33]. The hardness and elastic modulus of the buccal enamel surfaces were calculated using the software bundled with the nano-indentation apparatus.…”

Section: Mechanical Properties Of the Coatingsmentioning

confidence: 99%

Electrophoretic Deposition as a New Bioactive Glass Coating Process for Orthodontic Stainless Steel

et al. 2017

Self Cite

View full text Add to dashboard Cite

This study investigated the surface modification of orthodontic stainless steel using electrophoretic deposition (EPD) of bioactive glass (BG). The BG coatings were characterized by spectrophotometry, scanning electron microscopy with energy dispersive X-ray spectrometry, and X-ray diffraction. The frictional properties were investigated using a progressive load scratch test. The remineralization ability of the etched dental enamel was studied according to the time-dependent mechanical properties of the enamel using a nano-indentation test. The EPD process using alternating current produced higher values in both reflectance and lightness. Additionally, the BG coating was thinner than that prepared using direct current, and was completely amorphous. All of the BG coatings displayed good interfacial adhesion, and Si and O were the major components. Most BG-coated specimens produced slightly higher frictional forces compared with non-coated specimens. The hardness and elastic modulus of etched enamel specimens immersed with most BG-coated specimens recovered significantly with increasing immersion time compared with the non-coated specimen, and significant acid-neutralization was observed for the BG-coated specimens. The surface modification technique using EPD and BG coating on orthodontic stainless steel may assist the development of new non-cytotoxic orthodontic metallic appliances having satisfactory appearance and remineralization ability.

show abstract

Comparisons of nanoindentation, 3-point bending, and tension tests for orthodontic wires

Cited by 47 publications

References 19 publications

The effects of single application of pastes containing ion-releasing particles on enamel demineralization

The effects of single application of pastes containing ion-releasing particles on enamel demineralization

Effects of CO<sub>2</sub> laser irradiation combined with fluoride application on the demineralization, mechanical properties, structure, and composition of enamel

Electrophoretic Deposition as a New Bioactive Glass Coating Process for Orthodontic Stainless Steel

Contact Info

Product

Resources

About