著者
Kentaro Okamura Hiroyasu Koizumi Akihisa Kodaira Hiroshi Nogawa Takayuki Yoneyama
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.61, no.2, pp.358-363, 2019 (Released:2019-06-18)
参考文献数
21
被引用文献数
8

The purpose of this study was to evaluate the surface properties and gloss of CAD/CAM composites after toothbrush abrasion testing. Four CAD/CAM composites for molars (Cerasmart 300, Estelite P block, Katana Avencia P block, and KZR-CAD HR3 Gammatheta), one CAD/CAM composite for premolars (Shofu Block HC Hard), and one feldspathic ceramics (Vitablocs Mark II) were assessed. Knoop hardness number, gloss, and surface roughness (Ra, Rz, and Sa) were measured before and after toothbrush abrasion testing. Knoop hardness number values were in the order Vitablocs Mark II > Katana Avencia P block > Estelite P Block > Shofu Block HC Hard > Cerasmart 300 > KZR-CAD HR3 Gammatheta. After testing, the gloss of Estelite P block and KZR-CAD HR3 Gammatheta was greatly decreased and surface roughness was greatly increased. Periodic recall and re-polishing may thus be necessary when these products are used clinically.
著者
Hideyuki Imai Hiroyasu Koizumi Akihisa Kodaira Kentaro Okamura Shunsuke Akahane Hideo Matsumura
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.61, no.1, pp.178-183, 2019 (Released:2019-03-28)
参考文献数
16
被引用文献数
1

This study evaluated the light intensity of light-emitting diode (LED) units and the effects of five laboratory polymerization units on hardness and flexural strength. Two indirect composite materials (Cesead N and Solidex Hardura) were polymerized with five units (α-Light II, Hyper LII, LED Cure Master, Twinkle LED, and α-Light V). The light intensity of the devices was measured with a spectroradiometer. After light exposure, Knoop hardness number, flexural strength, and elastic modulus were determined. Evaluation of light intensity, using a wavelength range of 400 to 500 nm, revealed that the α-Light V and Hyper LII units had the highest light intensity. For the top surface of the two composites, the Knoop hardness number was significantly higher for the α-Light V and Hyper LII. For the two composite materials, flexural strength did not differ among the five polymerizing units. The present results indicate that the Cesead N and Solidex Hardura composites can be adequately polymerized with laboratory LED units.
著者
Osamu Saiki Hiroyasu Koizumi Nobutaka Akazawa Akihisa Kodaira Kentaro Okamura Hideo Matsumura
出版者
日本大学歯学部
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.58, no.1, pp.117-123, 2016 (Released:2016-03-26)
参考文献数
20
被引用文献数
12

This study compared the wear characteristics of a heat-pressed lithium disilicate ceramic material opposed to feldspathic porcelain, a lithium disilicate glass ceramic, and zirconia materials. Ceramic plate specimens were prepared from feldspathic porcelain (EX-3 nA1B), lithium disilicate glass ceramics (e.max CAD MO1/C14), and zirconia (Katana KT 10) and then ground or polished. Rounded rod specimens were fabricated from heat-pressed lithium disilicate glass ceramic (e.max press LT A3) and then glazed or polished. A sliding wear testing apparatus was used for wear testing. Wear of glazed rods was greater than that of polished rods when they were abraded with ground zirconia, ground porcelain, polished porcelain, or polished lithium disilicate ceramics. For both glazed and polished rods, wear was greater when the rods were abraded with ground plates. The findings indicate that application of a polished surface rather than a glazed surface is recommended for single restorations made of heat-pressed lithium disilicate material. In addition, care must be taken when polishing opposing materials, especially those used in occlusal contact areas. (J Oral Sci 58, 117-123, 2016)