著者
Hiroshi NOGAWA Hiroyasu KOIZUMI Osamu SAIKI Haruto HIRABA Mitsuo NAKAMURA Hideo MATSUMURA
出版者
日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
pp.2014-227, (Released:2015-02-24)
参考文献数
34
被引用文献数
2 12

The purpose of this study was to evaluate the shear bond strength and durability of 4-META/MMA-TBB resin to human enamel. A self-etching primer that contained 4-META (Teeth Primer, TP) and 35–45% or 60–65% concentrations of phosphoric acid (K-Etchant Gel, KE, and Super Bond C&B Red Activator, RA) were used as the surface treatment agents. A methyl methacrylate (MMA)-based self-polymerizing resin (Super-Bond C&B) was used as a luting agent. The shear bond strength was determined both pre and post thermocycling. The results were statistically analyzed with a non-parametric procedure. The post-thermocycling shear bond strength of the TP group was significantly higher than that of other groups, and that of the KE group was significantly higher compared with the RA group. These results demonstrated that 4-META was effective. Furthermore, when the degree of tooth demineralization was compared, surface treatment with less demineralization using TP was the most effective treatment.
著者
Yusuke SUZUKI Makoto HAYASHI Takuya YASUKAWA Hiroshi KOBAYASHI Kosuke MAKINO Yoriyuki HIRANO Shozo TAKAGI Laurence C. CHOW Bunnai OGISO
出版者
日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
pp.2014-255, (Released:2015-02-25)
参考文献数
31
被引用文献数
5

Aim of this study was to develop a novel fluorapatite-forming calcium phosphate cement (FA-CPC) with tricalcium silicate (TCS) for endodontic applications and to examine its in vitro and in vivo characteristics. The FA-CPC powder consisted of 62.8% CaHPO4, 30.8% CaCO3, and 6.4% NaF. One part of TCS was combined with 9 parts of FA-CPC powder (FA-CPC with TCS). A 1.5 M phosphate solution was used as cement liquid. Setting time (ST), diametral tensile strength (DTS), phase composition by X-ray diffraction (XRD), and cement alkalinity were analyzed. Cement biocompatibility was assessed using rat subcutaneous model. Cement ST was 10.3±0.6 min and DTS was 3.89±0.76 MPa. XRD patterns showed that highly crystalline apatitic material was the only significant phase present and pH value was approximate 11.0. FA-CPC with TCS demonstrated similar biocompatibility as that of mineral trioxide aggregate control. These results suggest that FA-CPC with TCS may be useful for endodontic applications.
著者
Mayumi KOTAKU Ryosuke MURAYAMA Yutaka SHIMAMURA Fuminori TAKAHASHI Takayuki SUZUKI Hiroyasu KUROKAWA Masashi MIYAZAKI
出版者
日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.33, no.5, pp.648-655, 2014-09-30 (Released:2014-10-01)
参考文献数
33
被引用文献数
11

Effects of a fluoride-releasing varnish containing surface reaction-type prereacted glass ionomer (S-PRG) filler on dentin demineralization were examined using optical coherence tomography. Bovine incisors that were sliced and treated with undersaturated 0.1 M lactic acid buffer solution (DE group). A thin film of varnish-containing S-PRG filler was applied before demineralization (PRG group). Control was maintained in artificial saliva. Using optical coherence tomography of selected locations on the dentin surface, peak intensity (dB) and width (μm) at 1/e2 were obtained and integrated values calculated. Although alterations in integrated values were different in each group, there was a slight but not significant increase in those for the control group and a slight but significant increase for the De group. For the PRG group, integrated values were doubled seven days after experiment initiation, followed by a significant increase. Fluoride-releasing varnish containing S-PRG fillers prevented dentin demineralization as detected by optical coherence tomography.
著者
Futoshi KOMINE Kohei TAGUCHI Ryosuke FUSHIKI Shingo KAMIO Taro IWASAKI Hideo MATSUMURA
出版者
日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.33, no.5, pp.607-613, 2014-09-30 (Released:2014-10-01)
参考文献数
29
被引用文献数
1 16

This study evaluated fracture load of single-tooth, implant-supported, zirconia-based, porcelain- and indirect composite-layered restorations after artificial aging. Forty-four zirconia-based molar restorations were fabricated on implant abutments and divided into four groups, namely, zirconia-based all-ceramic restorations (ZAC group) and three types of zirconia-based composite-layered restorations (ZIC-P, ZIC-E, and ZIC groups). Before layering an indirect composite material, the zirconia copings in the ZIC-P and ZIC-E groups were primed with Clearfil Photo Bond and Estenia Opaque Primer, respectively. All restorations were cemented on the abutments with glass-ionomer cement and then subjected to thermal cycling and cyclic loading. All specimens survived thermal cycling and cyclic loading. The fracture load of the ZIC-P group (2.72 kN) was not significantly different from that of the ZAC group (3.05 kN). The fracture load of the zirconia-based composite-layered restoration primed with Clearfil Photo Bond (ZIC-P) was comparable to that of the zirconia-based all-ceramic restoration (ZAC) after artificial aging.
著者
Ayako KAWABE Ichiro NAKAGAWA Zuisei KANNO Yusuke TSUTSUMI Takao HANAWA Takashi ONO
出版者
日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.33, no.5, pp.638-647, 2014-09-30 (Released:2014-10-01)
参考文献数
50
被引用文献数
1 12

Titanium (Ti) is widely used for oral cavity biomedical devices. However, because it penetrates the mucosa and exists partially external to the tissue, it sometimes induces tissue inflammation, minor infection, or peri-implantitis due to oral bacteria after implantation and causes serious consequences. We have previously shown that poly(ethylene glycol) (PEG)- electrodeposited Ti inhibits bacterial adhesion and biofilm formation. However, the effect of the PEG coating in body fluid is still unclear. In this study, we investigated bacterial colony morphology and biofilm formation on PEG-electrodeposited Ti in comparison with untreated Ti in the presence of saliva. After 48 h incubation, Streptococcus mutans biofilms adhered on the untreated Ti were rigid and cohesive, while those on the PEG-electrodeposited were loose and were easily washed off. These results indicate electrodeposited-PEG layers inhibit the biofilm formation on Ti in the presence of saliva.
著者
有働 公一 久恒 邦博 安田 克廣 太田 道雄
出版者
一般社団法人日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.3, no.2, pp.253-261, 333, 1984-12-25
被引用文献数
25

パラジウムを含有する市販歯科用14K,16K金合金の等温時効による硬さの変化とその原因機構について,電気抵抗測定,硬さ試験,X線回折,電子顕微鏡直接観察,制限視野電子線回折によって検討した。時効硬化は準安定相であるAuCu I'規則格子の形成に伴う整合ひずみによって生ずる。AuCu I'規則相は反応の進行とともにひずみを解散するため双晶化するが,これによる過時効軟化は顕著ではない。過時効軟化は平衡相AuCu I規則格子とAg-rich α_2相の二相分離が結晶粒界から起こることによって生じ,その原因はこれら二相によって形成されたラメラ構造の界面が非整合になるためであることが解った。
著者
Stefano TETÈ Vincenzo Luca ZIZZARI Bruna BORELLI Marianna DE COLLI Susi ZARA Roberto SORRENTINO Antonio SCARANO Enrico GHERLONE Amelia CATALDI Fernando ZARONE
出版者
日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.33, no.1, pp.7-15, 2014-01-30 (Released:2014-02-01)
参考文献数
34
被引用文献数
5 31

Human gingival fibroblasts (HGFs) were cultured onto CAD/CAM zirconia (Group A), CAD/CAM zirconia after polishing (Group B), CAD/CAM lithium disilicate after polishing (Group C), and feldspathic ceramic (Group D) to evaluate their proliferation and adhesion potential. After 3 h, HGF adhesion was similar in all groups. Later, HGFs closely adhered to surfaces, particularly onto groups B, C and D, acquiring an elongated shape. Proliferation assay showed no differences in cell viability among the groups after 24 h, while significant increase was shown after 72 h in Groups B and C. After 24 h, similar Collagen I levels were found in all groups, while after 72 h Groups B and C revealed a deep reduction in respect to the 24 h level. In vitro, HGF behavior may reflect variability in soft tissue response to different surface materials for prosthetic restorations, and support that polished zirconia is able to achieve a better integration in vivo in respect to the other materials.
著者
Maho SHIOZAWA Hidekazu TAKAHASHI Werner J. FINGER Naohiko IWASAKI
出版者
日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.32, no.1, pp.150-155, 2013-01-31 (Released:2013-02-01)
参考文献数
14
被引用文献数
2 4

Aim of this study was to investigate effects of space thickness and consistency of wash materials on sulcus depth reproduction with silicone impressions, low (L), medium (M), and very high consistency (VH), using two-step putty-wash technique. Impressions were taken from truncated cones with 50-, 100-, or 200-μm-wide sulci, using the combinations L+VH or M+VH and different space thickness for wash materials: 2 mm (ST2), 1 mm (ST1), and approximately 25 μm (ST0.025). Sulcus depth reproduction tended to increase with increasing sulcus width. Sulcus reproduction of ST0.025 was deeper than those of the other groups. At 100- and 200-μm sulcus widths, sulcus reproductions of ST1 and ST2 with L+HV were deeper than with M+HV. Regardless of consistency, the thin spacer produced deep reproduction. Adequate 0.5 mm sulcus reproductions were obtained with 100 and 200 μm wide sulci and 1- and 2-mm spacer widths, combined with low consistency impression material.
著者
Ugur ERDEMIR Esra YILDIZ Meltem Mert EREN Sevda OZEL
出版者
日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.31, no.5, pp.729-736, 2012-10-02 (Released:2012-10-02)
参考文献数
40
被引用文献数
1 28

The purpose of this study was to evaluate the effect of sports and energy drinks on the surface hardness of different restorative materials over a 6-month period. Forty-two disk-shaped specimens were prepared for each of the four restorative materials tested: Compoglass F, Filtek Z250, Filtek Supreme, and Premise. Specimens were immersed for 2 min daily, up to 6 months, in six storage solutions (n=7 per material for each solution): distilled water, Powerade, Gatorade, X-IR, Burn, and Red Bull. Surface hardness was measured at baseline, after 1 week, 1 month, and 6 months. Data were analyzed statistically using repeated measures ANOVA followed by the Bonferroni test for multiple comparisons (α=0.05). Surface hardness of the restorative materials was significantly affected by both immersion solution and immersion period (p<0.001). All tested solutions induced significant reduction in surface hardness of the restorative materials over a 6-month immersion period.
著者
菅原 明喜 西山 實 草間 薫 茂呂 周 西村 敏 工藤 逸郎 CHOW Laurence C. 高木 章三
出版者
一般社団法人日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.11, no.1, pp.11-16, 111, 1992-06-25
被引用文献数
16 63

Calcium Phosphate Cement(CPC)は,水の介在下において常温で短時間のうちにHydroxyapatite(HAp)に転化することが知られており,臨床的な報告もいくつかなられている。今回は,根管充填用に開発された数種のCPCペーストの生体親和性についてラットを用いた組織反応試験を行い,市販根管充填材料と比較することによって検討を行った。 その結果,CPCをベースとした各種試作根管充填材料は,市販のものと比較して極めて良好な生体親和性を示し,HApそのものと比較しても組織反応における明確な違いはなかった。今回使用した市販の根管充填材料は,既に臨床で広く用いられ充分な評価を得ているものばかりなので,本材料も臨床に応用し得るものであることが示唆された。
著者
Duck-Su KIM Sang Hyuk PARK Gi-Woon CHOI Kyoung-Kyu CHOI Sun-Young KIM
出版者
The Japanese Society for Dental Materials and Devices
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.30, no.5, pp.717-722, 2011 (Released:2011-10-08)
参考文献数
26
被引用文献数
12 14

The effect of the ethylenediaminetetraacetic acid (EDTA) treatment on the hybrid layer durability of total-etch dentin adhesives was investigated. A flat dentin surface was exposed and treated with 37% phosphoric acid or 0.1M EDTA. Dentin adhesive was applied and a 4 mm thick composite resin was built-up. Twenty 0.9×0.9 mm2 resin-dentin beams were fabricated in each experimental group. Artificial aging with 10% NaClO was performed in half of the experimental groups for 1 hour. A micro-tensile bond strength (μTBS) test was performed and the bonded interface was analyzed with transmission electron microscopy (TEM). The 37% phosphoric acid-treated group showed a lower μTBS after artificial aging, whereas the 0.1M EDTA-treated group did not. TEM analysis revealed collagen fibrils dissolved in the 37% phosphoric acid-treated group but not in the 0.1M EDTA-treated group. Undissolved minerals were observed in the 0.1M EDTA-treated group. In conclusion, a dentin treatment with 0.1M EDTA is effective in improving the hybrid layer durability.
著者
Kenji ARITA Aimi YAMAMOTO Yukari SHINONAGA Keiko HARADA Yoko ABE Keizo NAKAGAWA Shigeru SUGIYAMA
出版者
The Japanese Society for Dental Materials and Devices
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.30, no.5, pp.672-683, 2011 (Released:2011-10-08)
参考文献数
39
被引用文献数
40 63

The aims of this study were to improve the mechanical and chemical properties of conventional restorative glass ionomer cement (GIC) by adding hydroxyapatite (HAp) preparations with different characteristics, and to investigate the underlying reaction mechanisms. Fuji IX GP® was used as the control GIC. The experimental GICs consisted of four HAp-particles with different characteristics added at 8 mass% to Fuji IX-powder. All cements were prepared by mixing with Fuji IX-liquid (P/L=3.6). Four HAp-particles were analyzed, and then the mechanical strengths and the fluoride-ion- release-recharge-behaviors of five GIC groups were evaluated. The results of this study demonstrate that the addition of HAp particles with highly reactive properties such as high specific surface area can enhance the flexural strength and fluoride ion release properties of conventional restorative GIC. Our results further indicate that HAp functions as an adsorbent and an ion exchangeable agent, resulting in improved mechanical and chemical properties of GIC.
著者
藤井 孝一
出版者
一般社団法人日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.8, no.2, pp.243-259, 288, 1989-12-25
被引用文献数
6 28

義歯床用材料(PMMA)に関して,曲げ疲労試験及び引張疲労試験を行った。さらに引張疲労試験に伴う粘弾性と引張特性の変化を調べた。 その結果,疲労試験後の破面の比較では,曲げ疲労による破面は,引張側の表面からクラックが開始し,その後のクラックの進行を表わすstriationが観察され,破壊にいたるという様相を示す。一方,引張疲労の場合にも類似の傾向が認められる。 疲労に伴う粘弾性の変化については,疲労が進むと貯蔵弾性率(E')は,測定されたすべての温度領域で低下する。一方,損失弾性率(E''),損失正接(tanδ)はわずかづつ増加する傾向を示した。また,弾性率,引張強さ,靭性などは,10^4回の繰り返し数で,すでに低下を示していた。これらの結果は,疲労に伴うクラックの発生が材料の劣化を招いたものと考えられる。 義歯床用材料として使用されている4種類の市販品の疲労特性を調べた。流し込み型レジンの疲れ強さは加熱重合型より小さく,材料間で大きくことなる。このばらつきの一因として,材料組成の違い,未反応物質の量の違いなどが考えられる。
著者
千木良 尚志 真鍋 厚史 伊藤 和雄 和久本 貞雄 早川 徹
出版者
一般社団法人日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.8, no.2, pp.194-199, 286, 1989-12-25
被引用文献数
34 33

Glyceryl methacrylate水溶液の,dentin primerとしての効果を象牙質円柱窩洞内での,可視光線重合型コンポジットレジンのコントラクションギャップの計測と象牙質平面に対する引っ張り接着強さの計測によって評価した。被着象牙質面は,pH7.4に調整された0.5M濃度のEDTAによって歯面清掃を行った後,5%から45%までのGlyceryl methacrylate水溶液を塗布し,その後市販のリン酸エステル系ボンディング材を併用して市販の光重合型コンポジットレジンを填塞または接着させた。また,コントロールとして35%HEMA水溶液と5%glutaraldehydeを含む35%HEMA水溶液をprimerとして用い,同様の計測を行った。 その結果,25%と35%の濃度のGlyceryl methacrylate水溶液をdentin primerとして用いた場合に,全試片でギャップが全く認められず,完全な窩洞適合性が得られた。また,24時間後には,25%および35%水溶液で,それぞれ平均19.6および18.7MPaの平均接着力が得られた。
著者
平野 進 平沢 忠
出版者
一般社団法人日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.8, no.1, pp.93-99, 124-125, 1989-06-25
被引用文献数
5

コンポジットレジンの圧縮クリープを4種の異なる応力(圧縮応力0∼3.5 kg/mm^2)で水中浸漬下で500時間にわたり行なった。得られた4種のクリープ曲線から,一定時間経過したときの各クリープひずみと圧縮応力との間には一次回帰式が成立した。そのためコンポジットレジンの500時間後の吸水飽和状態になったときのクリープひずみは圧縮応力が分かれば予測可能となった。またこの回帰式を使い,各時間における吸水膨張応力を求めた。最大吸水膨張応力はコンポジットレジンが吸水飽和したときに得られ,その値は0.74 kg/mm^2であった。各応力下で得られたクリープ曲線をひずみ一対数時間曲線で表すと,初期の数十時間は直線となった。
著者
SHIMURA Rena NIKAIDO Toru YAMAUTI Monica IKEDA Masaomi TAGAMI Junji
出版者
一般社団法人日本歯科理工学会
雑誌
Dental materials journal (ISSN:02874547)
巻号頁・発行日
vol.24, no.1, pp.70-75, 2005-03
被引用文献数
8 33

This study evaluated the influence of curing method and storage condition on the microhardness of dual-cure resin cements : Panavia F 2.0 (PF) and Nexus 2 (NX). The specimens were either light-cured (LC) or chemically cured in darkness (CC). After 24 hours of storage in dry chamber (Dry) or distilled water (DW), the specimens were sectioned and polished. The microhardness of resin cement matrix was measured using a nanoindentation tester (ENT-1100). The data (n=6) were statistically analyzed with t-test, two-way ANOVA (p<0.05), and Tukey HSD test (α=.05). It was found that the factors of curing method and storage condition had significant effect on microhardness. For both PF and NX, LC presented higher microhardness than CC, while DW showed higher microhardness than Dry. In conclusion, dual-cure resin cements could achieve high degree of cure when light-cured. In addition, the microhardness of the resin cements evaluated did not decrease when kept in water.
著者
KANNO Tama OGATA Miwako FOXTON Richard Mark NAKAJIMA Masatoshi TAGAMI Junji MIURA Hiroyuki
出版者
一般社団法人日本歯科理工学会
雑誌
Dental materials journal (ISSN:02874547)
巻号頁・発行日
vol.23, no.4, pp.550-556, 2004-12
被引用文献数
13 14

The purpose of this study was to measure the bond strength of dual-cure resin cement at different regions of root canal dentin using three kinds of curing method. Thirty-six extracted bovine teeth were used. Each root was sectioned vertically into halves. Their pulpal dentin walls were polished flat and then applied with two dual-cure resin cements (Bistite II, Panavia F), and divided into three curing strategy groups : multi-direction light, one-direction light and no-light. The bonded specimens were sectioned perpendicularly to the long axis of the root into approximately 0.7 mm thick slabs within two-third of the root from the coronal end, and prepared for microtensile bond strength (μTBS) test. Knoop hardness of the cements was also measured. Within each curing strategy for both dual-cure resin cements, there were no significant differences between the μTBS values at the coronal third and mid third regions. The effect of curing method on bond strength and KHN was found to be dependent on the material.
著者
宮崎 光治 高田 十志和 遠藤 剛 稲永 昭彦
出版者
一般社団法人日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.13, no.1, pp.9-18, 123, 1994-06-25
被引用文献数
1 13

スピロオルトエステルを側鎖に持つアクリレート(ASOE)およびメタクリレート(MASOR)を合成し,その重合と得られた重合体の性質について検討した.スピロオルトエステルはイオン重合開始剤(BSS, HPSS)による加熱重合によって良く開環重合した.しかし,得られた重合体には少量の未反応の二重結合が見られた.また,ラジカル重合開始剤(BPO, AIBN, DTBおよびCQ)による重合ではビニール基の重合のみならず開環重合も低調であった.BSS ,AIBNおよびBPO/BSSによる加熱重合によって得られたMASOE重合体はプラスチックス状であった.ASOEおよびMASOEのイオン重合開始剤による加熱重合や紫外線重合における重合収縮は汎用のモノメタクリレートに比べて有意に小さかった.
著者
松家 茂樹 松家 洋子 山本 泰 山根 正次
出版者
一般社団法人日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
vol.3, no.2, pp.210-219, 332, 1984-12-25
被引用文献数
10 38

酢酸,乳酸,クエン酸および塩酸中におけるグラスアイオノマーセメントの侵食過程を化学分析,SEM観察および赤外吸光分析により検討した。各酸の陰イオンとAl又はCaとの錯体の安定度定数が大きい程あるいは,酸溶液のpHが低い程,Al,Ca,Na,SiおよびFの溶出量が多くなった。SEM観察により,0.01Mクエン酸および塩酸中ではセメントマトリックスが溶解することが分かった。0.01Mクエン酸および塩酸中では,セメント浸漬後に白色沈殿が生成した。その沈殿は,水和ケイ酸質ゲルであることがIRスペクトルによりわかった。