著者

Md.Sofiqul ISLAM Noriko HIRAISHI Mohannad NASSAR Ryohei SONO Masayuki OTSUKI Tsutomu TAKATSURA Cynthia YIU Junji TAGAMI

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.31, no.3, pp.362-367, 2012 (Released:2012-05-28)

参考文献数

36

被引用文献数

18 29

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The aims of this study were to investigate the effects of hesperidin, a citrus flavonoid, on human root dentin demineralization and collagen preservation, and compare it with chlorhexidine and grape seed extract. Specimens were assigned to different treatment groups: hesperidin, chlorhexidine and grape seed extract. Specimens were subjected to pH cycling by demineralization for 14 h, incubation in testing solutions for 2 h and remineralization in presence of bacterial-derived collagenase for 8 h, for 8 days. Calcium release was measured by means of an atomic absorption spectrophotometer, and degraded collagen matrix was investigated by hydroxyproline assay. Specimens were assessed longitudinally with transverse micro-radiography to investigate lesion depth and mineral loss. In hesperidin and grape seed extract groups, demineralization was reduced when the collagen matrix was preserved. The hesperidin group showed the lowest value in lesion depth and mineral loss, indicating that hesperidin inhibited demineralization and probably enhanced remineralization even under fluoride-free conditions.

著者

Mohammed M GAD Ahmed RAHOMA Ahmad M Al-THOBITY

出版者

The Japanese Society for Dental Materials and Devices

雑誌

Dental Materials Journal (ISSN:02874547)

巻号頁・発行日

pp.2017-191, (Released:2018-06-20)

参考文献数

42

被引用文献数

21

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The current study evaluated the effects of autoclave polymerization both with and without glass fiber (GF) reinforcement on the surface roughness and hardness of acrylic denture base material. Ninety disc specimens (30×2.5 mm) were prepared from Vertex resin and divided according to polymerization techniques into a water bath, short and long autoclave polymerization groups. Tested groups were divided into three subgroups according to the GF concentration (0, 2.5, and 5 wt%). Profilometer and Vickers hardness tests were performed to measure surface roughness and hardness. ANOVA and Tukey-Kramer multiple comparison tests analyzed the results, and p≤0.05 was considered statistically significant. Autoclave polymerization significantly decreased the surface roughness and increased the hardness of acrylic resin without GF reinforcement (p<0.05). However, 5 wt% GF addition significantly increased surface roughness and decreased hardness of the autoclave polymerized denture base resin (p<0.05). Surface properties of Polymethyl methacrylate (PMMA) denture base material improved with autoclave polymerization and negatively affected with GFs addition.

著者

Mohammed A. ALSHEHRI Jagan Kumar BASKARADOSS Amrita GEEVARGHESE Ravikumar RAMAKRISHNAIAH Dimitris N. TATAKIS

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.2013-317, (Released:2015-01-19)

参考文献数

62

被引用文献数

2 8

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The present in vitro study sought to determine the effects of myrrh-containing solutions on common suture materials used in periodontal surgery. Three commonly used suture materials (silk, polyglactin 910, polytetrafluoroethylene) were immersed in four thermostatically controlled experimental media to simulate daily oral rinsing activity, namely —artificial saliva, normal saline solution with 0.2% Commiphora myrrh, full-concentration (100%) Commiphora myrrh oil, and a myrrh-containing commercial mouthwash. Tensile strength was measured at the end of each day using an Instron tensile testing machine. Silk sutures were susceptible to tensile strength loss when exposed to 0.2% myrrh solution once daily for 5 days. Myrrh-containing commercial mouthwash had no effect on tensile strength, but all three suture materials lost tensile strength when exposed to 100% myrrh oil. For patients that routinely use myrrh mouthwashes postoperatively, findings of this study suggested that silk sutures might not be the optimal material choice.

著者

Aye KO KO Naoko MATSUI Ayako NAKAMOTO Masaomi IKEDA Toru NIKAIDO Michael F. BURROW Junji TAGAMI

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.39, no.3, pp.407-414, 2020-05-27 (Released:2020-06-05)

参考文献数

32

被引用文献数

11 16

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The purpose of this study was to evaluate the effects of two different concentrations of silver diammine fluoride (SDF) on dentin bonding performance. Human mid-coronal dentin was treated with either distilled water (control), 3.8%SDF or 38%SDF for 3 min. A two-step self-etch adhesive and resin composite were applied according to manufacturer’s instructions. After thermocycling (TC) at 0, 5,000 and 10,000 cycles, microtensile bond strength (µTBS) testing and morphological assessment of resin-dentin bonding interface were performed. At 0 TC, µTBSs of 3.8% and 38%SDF were significantly reduced (p<0.05). At 5,000 and 10,000 TC, µTBSs of 3.8%SDF were comparable to those of the control group, whereas the µTBSs of 38%SDF were significantly lower (p<0.05). Acid-base resistance zone formation was observed in all groups, however, slope-shaped formation was identified only in the SDF groups. The µTBSs and interfacial morphology were influenced by concentration of SDF and also TC.

著者

有川 裕之 藤井 孝一 蟹江 隆人 上新 和彦 井上 勝一郎 鬼塚 雅 自見 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.1, no.1, pp.67-72, 1982-12-25

被引用文献数

7

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印象材の操作時間,硬化時間を決定するために種々の方法が試みられてきた。そのひとつとしてウィルソン(1964)は硬化時における印象材の粘弾性変化を測定することによって操作時間,硬化時間を決定するための装置レシプロケーティングレオメータを開発した。しかし印象材の操作時間,硬化時間は粘弾性の変化よりもむしろ硬化時の弾性変化から決定するほうが臨床的にみて好ましいと思われる。そこで本研究ではそのための装置としてパルセーティングレオメータを開発した。この装置は試料にくり返し一定ひずみを加え,その弾性回復量を測定することによって操作時間,硬化時間を決定するものである。種々の印象材について測定を行った結果,本装置は操作時間,硬化時間の決定ならびに効果時における印象材のレオロジー的性質をも知ることができるので印象材の比較検討を行う上で有効であることがわかった。

著者

Takashi KAMEDA Kazuo OHKUMA Nozomu ISHII Natsuki SANO Hideo OGURA Kazuto TERADA

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.856-862, 2012-10-02 (Released:2012-10-02)

参考文献数

13

被引用文献数

3 5 4

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Magnetic fields can represent a health problem, especially low frequency electromagnetic fields sometimes induced by electric current in metallic objects worn or used in or on the body (as opposed to high frequency electromagnetic fields that produce heat). Electric toothbrushes are widely used because of their convenience, but the electric motors that power them may produce electromagnetic waves. In this study, we showed that electric toothbrushes generate low frequency (1-2000 Hz) magnetic fields and induce electric current in dental appliances (e. g. orthodontic and prosthetic appliances and dental implants). Current induced by electric toothbrushes might be dependent on the quantity and types of metals used, and the shape of the appliances. Furthermore, these induced currents in dental appliances could impact upon human oral health, producing pain and discomfort.

著者

Motohiro UO Tsukasa AKASAKA Fumio WATARI Yoshinori SATO Kazuyuki TOHJI

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.3, pp.245-263, 2011 (Released:2011-06-02)

参考文献数

106

被引用文献数

49 66

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After the discovery of fullerene and carbon nanotubes, various carbon nanomaterials were discovered or synthesized. The carbon nanomaterials have remarkable properties, different from bulk materials with the same chemical composition, and are therefore useful for industrial applications. However, the toxicity of nanomaterials may also differ from that of the bulk materials; this difference poses a concern. The physical similarity of nanomaterials to asbestos has led to evaluations for toxicity by many researchers using various methods. In this review, we compile and compare the toxicity evaluations of each carbon nanomaterial.

著者

Imran FAROOQ Abdul Samad KHAN Imran Alam MOHEET Emad ALSHWAIMI

出版者

The Japanese Society for Dental Materials and Devices

雑誌

Dental Materials Journal (ISSN:02874547)

巻号頁・発行日

pp.2020-078, (Released:2020-11-19)

参考文献数

24

被引用文献数

7

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The aim was to synthesize a toothpaste and analyze its effect on surface micro-hardness and roughness of enamel. Basic paste was prepared by using basic ingredients. Theobromine (0.2 wt%) and laboratory synthesized fluoridated-bioactive glass (F-BG, 4 wt%) were added to it. Post-demineralization, 36 enamel blocks were divided into six groups that were brushed with their respective toothpaste+artificial saliva (AS): group 1 (control): basic paste; group 2: basic paste+theobromine; group 3: commercial theobromine toothpaste; group 4: commercial BG toothpaste; group 5: basic paste+F-BG; and group 6: basic paste+theobromine+F-BG. On micro-hardness analysis, group 6 performed best, followed by group 4. Surface roughness results showed the maximum decrease in roughness values for group 6, followed by group 5. Treatment with toothpaste composition containing theobromine+F-BG resulted in the enamel’s increased micro-hardness and decreased surface roughness.

著者

Tool SRIAMPORN Niyom THAMRONGANANSKUL Chumphol BUSABOK Sushit POOLTHONG Motohiro UO Junji TAGAMI

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.33, no.1, pp.79-85, 2014-01-30 (Released:2014-02-01)

参考文献数

65

被引用文献数

27 70

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The surface morphology and crystal structure change of dental zirconia after hydrofluoric acid (HF) etching were evaluated. Four groups of sintered zirconia specimens were 1) control group, 2) immersion in 9.5%HF at 25oC for 1, 2, 3, or 24 h, 3) immersion in 9.5%HF at 80oC for 1, 3, 5, or 30 min and 4) immersion in 48%HF at 25oC for 30 or 60 min. The specimens were evaluated under SEM and XRD. The SEM analysis revealed changes in surface topography for all the HF-etched zirconia specimens. The irregularities surface increased with increasingly longer immersion times and higher etching solution temperatures. The XRD analysis of the HFetched zirconia specimens revealed the presence of a crystalline monoclinic phase along with a tetragonal form. It was concluded HF can etch dental zirconia ceramic, creating micro-morphological changes. Tetragonal-to-monoclinic phase transformation was induced on the etched zirconia surface.

著者

Maryam MOSHAVERINIA Ali BORZABADI-FARAHANI Abdi SAMENI Alireza MOSHAVERINIA Sahar ANSARI

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.35, no.5, pp.817-821, 2016-09-29 (Released:2016-10-01)

参考文献数

25

被引用文献数

6 24

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Present study evaluated effects of addition of Nanoparticles fluorapatite (Nano-FA) on microhardness and fluoride release of a Glass Ionomer Cement (GIC, Fuji IX GP Fast). Forty-eight specimens prepared, divided equally into 4 groups (2 with Nano-FA); after 24 h and one week Vickers microhardness (HV) was measured. Nano-FA specimens were made from addition of nano-FA to Fuji IX powder (glass powder/Nano-FA ratio=20:1 wt/wt, 3.6:1 P/L ratio). At 24 h, mean (95% CI) HV for GIC and Nano-FA GIC were 40.59 (39.51–41.66) and 46.89 (45.95–47.82) kg/mm2, and at one week 44.98 (44.23–45.72), 53.29 (52.58–53.99) kg/mm2, respectively. Findings indicated higher HV in Nano-FA specimens (F=221.088, p<0.001). Twenty-eight days weekly cumulative fluoride release in both groups was not different (p>0.05). MTT assay exhibited no inhibition of cell proliferation or reduction in metabolic activity in experimental [84.0 (3.3)] or control groups [85.1 (4.7)] with no difference between groups (p>0.05). New nano-FA GIC was biocompatible and showed improved surface hardness. Future clinical trials can verify the usefulness of Nano-FA GIC.

著者

Cem SAHIN Zafer C. CEHRELI Muhittin YENIGUL Bulent DAYANGAC

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.3, pp.401-408, 2012 (Released:2012-05-28)

参考文献数

32

被引用文献数

4 15

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To investigate the permeability of deep dentin following immediate sealing with different etch-and-rinse and self-etch adhesives (Single Bond 2, Adper Prompt L-Pop, Clearfil Protect Bond, Clearfil S3 Bond, G-Bond) and a dentin desensitizer (Gluma). Fluid-transport model was used to measure fluid conductance during and after application of adhesives. Polyvinylsiloxane impressions of bonded dentin were taken to monitor fluid transudation from the surface of the adhesives. The area and number of dentinal fluid droplets and/or blisters were calculated using image analysis. None of the adhesives were able to block fluid conductance completely. The fluid conductance values of the adhesives displayed the following statistical ranking (p<0.05): G-Bond≤Clearfil Protect Bond<Smear-layer-covered dentin<S3 Bond≤Single Bond 2≤Adper Prompt L-Pop<Gluma Desensitizer<Acid-etched dentin. Highly significant correlation was observed between the permeability of the tested adhesives and the area fraction of fluid droplets/blisters on the adhesive surfaces (r=0.99, p<0.01).

著者

INOUE Go NIKAIDO Toru SADR Alireza TAGAMI Junji

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.2, pp.232-238, 2012-03-01

参考文献数

27

被引用文献数

1 9

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This study investigated the influence of the composition of self-etching primer adhesive systems on the morphology of acid-base resistant zones (ABRZs). One-step self-etching primer systems (Clearfil Tri-S Bond, G-Bond, and One-Up Bond F Plus) and two-step self-etching primer systems (Clearfil SE Bond, Clearfil Protect Bond, UniFil Bond, and Mac Bond II) were used in this study. Each adhesive was applied on prepared dentin disk surfaces, and a resin composite was placed between two dentin disks. All resin-bonded specimens were subjected to acid-base challenge. Observation under a scanning electron microscope (SEM) revealed the creation of an ABRZ adjacent to the hybrid layer for all the self-etch primer adhesive systems, even when non-fluoride releasing adhesives were used. The presence of fluoride in two-step self-etching adhesive significantly increased the thickness of ABRZ created. Results suggested that an ABRZ was created with the use of self-etching primer adhesive systems, but its morphology differed between one-and two-step self-etching primer adhesive systems and was influenced by fluoride release activity.

著者

Yukiko IWASAKI Hisako HIRAGUCHI Eriko IWASAKI Takayuki YONEYAMA

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.35, no.1, pp.45-50, 2016-01-29 (Released:2016-01-31)

参考文献数

20

被引用文献数

10

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This study investigated the effects of disinfection of agar-alginate combined impressions on the surface properties of the resulting stone casts. Two brands of cartridge-form agar impression material and one alginate impression material were used. Agar-alginate combined impressions of smooth glass plates were prepared. The impressions were immersed in 0.55% ortho-phthalaldehyde solution or 0.5% sodium hypochlorite solution for 1, 3, 5 and 10 min. A stone cast made with an impression that had not been immersed was prepared as a control. The surface roughness (Ra) of the stone casts was measured, and the cast surfaces were observed by SEM. Immersion of agar-alginate combined impressions in 0.5% sodium hypochlorite solution for up to 10 min had no serious adverse effects on the surface properties of the stone casts. In contrast, even 1 min of immersion in 0.55% ortho-phthalaldehyde solution caused deterioration of the cast surface properties.

著者

Mohammed A. ALFARSI Stephen M. HAMLET Saso IVANOVSKI

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.2013-221, (Released:2014-10-11)

参考文献数

45

被引用文献数

4 27

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Titanium implant surface modification is a key strategy used to enhance osseointegration. Platelets are the first cells that interact with the implant surface whereupon they release a wide array of proteins that influence the subsequent healing process. This study therefore investigated the effect of titanium surface modification on the attachment and activation of human platelets. The surface characteristics of three titanium surfaces: smooth (SMO), micro-rough (SLA) and hydrophilic micro-rough (SLActive) and the subsequent attachment and activation of platelets following exposure to these surfaces were determined. The SLActive surface showed the presence of significant nanoscale topographical features. While attached platelets appeared to be morphologically similar, significantly fewer platelets attached to the SLActive surface compared to both the SMO and SLA surfaces. The SLActive surface however induced the release of the higher levels of chemokines β-thromboglobulin and platelet factor 4 from platelets. This study shows that titanium surface topography and chemistry have a significant effect on platelet activation and chemokine release.

著者

Jiale FU Feng PAN Shinichi KAKUDA Sharanbir K SIDHU Takatsumi IKEDA Yasuko NAKAOKI Denis SELIMOVIC Hidehiko SANO

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.6, pp.1075-1081, 2012-11-30 (Released:2012-12-01)

参考文献数

22

被引用文献数

2 13

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The purpose of this study was to evaluate the effect of air-blowing duration on the bonding performance of all-in-one systems using the same pressure (0.25 MPa). Three all-in-one systems were: EB (Easy Bond, 3M ESPE, USA), BB (BeautiBond, Shofu Inc., Japan) and GBp (G-Bond plus, GC Corporation, Japan). After adhesive application, the 3 systems were air-blown thereafter using 7 different durations (5 s, 10 s, 15 s, 20 s, 25 s, 30 s and 35 s). Bond strengths to dentin were determined using µTBS test after 24 h water storage. In addition, evaluation of both the resin-dentin interface and the fractured surface on the dentin side were performed by SEM. The maximum µTBS for each system, BB (40.4±14.8 MPa), EB (79.8±16.5 MPa), and GBp (47.3±17.6 MPa), were recorded with 15 s, 15 s and 25 s air-blowing duration respectively. Under the same air-pressure, the air-blowing duration could affect evaporation and the thickness of the adhesive layer, which contributed to the different bond strengths.

著者

Makoto NODA Yuji OKUDA Jiro TSURUKI Yoshito MINESAKI Yasumi TAKENOUCHI Seiji BAN

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.29, no.5, pp.536-541, 2010 (Released:2010-10-14)

参考文献数

21

被引用文献数

58 50

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The purpose of this study was to characterize the surface damages of zirconia by Nd:YAG dental laser irradiation through a systematic evaluation of the associated microstructural changes. Disk specimens of yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) and ceria-stabilized zirconia/alumina nanocomposite (Ce-TZP/Al2O3 nanocomposite) were irradiated by Nd:YAG dental laser. The specimens were characterized using scanning electron microscopy, X-ray diffractometry, and wavelength dispersive X-ray spectroscopy. Every single irradiated spot was indicated by a circular black pit surrounded by a circular raised rim with a sunken depression at the center. On surface changes, many cracks were formed inside each irradiated pit. On changes in elemental composition, the concentration of oxygen decreased while that of zirconium increased. After heating in air, the assembly of circular black pits turned white, although the depression and raised rim remained. This study showed that Nd:YAG dental laser irradiation induced cracking and reduced oxygen content on the surface of zirconia. Consequently, these phenomena reduced the mechanical strength of zirconia. Therefore, Nd:YAG dental laser welding should not be performed on tetragonal zirconia.

著者

Koji HAYASHI Ryo ISHII Tosihiki TAKAMIZAWA Shunichi SUDA Ryota AOKI Kana HAYASHI Atsushi KAMIMOTO Masashi MIYAZAKI

出版者

The Japanese Society for Dental Materials and Devices

雑誌

Dental Materials Journal (ISSN:02874547)

巻号頁・発行日

pp.2023-073, (Released:2023-11-23)

参考文献数

29

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This study aimed to evaluate the influence of surface pretreatment on the shear bond strength of resin luting cement to saliva-contaminated resin core foundation. The surface free energy (γS) of the adherent surfaces was examined. The two-way analysis of variance revealed that the surface pretreatment and storage conditions had a significant effect on the strength of the bond to resin core foundation. The γS values of the saliva-contaminated group were significantly lower than those of the other groups, and they tended to improve after surface pretreatment. The tendency of improvement in γS values differed depending on the type of pretreatment agents. Surface treatment with solutions containing functional monomers is effective in removing saliva contaminants from the resin core foundation surfaces and in creating an effective bonding surface for the resin luting cement.

著者

Hiroyasu KOIZUMI Haruto HIRABA Takayuki YONEYAMA Akihiro KUROIWA

出版者

The Japanese Society for Dental Materials and Devices

雑誌

Dental Materials Journal (ISSN:02874547)

巻号頁・発行日

pp.2023-113, (Released:2023-08-22)

参考文献数

63

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This review describes individual studies of removable dental prostheses, evaluated their performance and clinical applicability for the proposal to expand health insurance coverage of titanium and its alloys to removable dental prostheses. Titanium and its alloys have become clinically applicable as prosthetic materials by improving dental casting systems. They have high biosafety and good mechanical properties, are excellent substitutes for the silver-palladium-gold alloys for casting, and are highly useful for removable dental prostheses. Therefore, the introduction of health insurance coverage for removable dental prostheses made of titanium and its alloys is worthy of consideration.

著者

Kana HAYASHI Hiroyasu KUROKAWA Makoto SAEGUSA Ryota AOKI Toshiki TAKAMIZAWA Atsushi KAMIMOTO Masashi MIYAZAKI

出版者

The Japanese Society for Dental Materials and Devices

雑誌

Dental Materials Journal (ISSN:02874547)

巻号頁・発行日

pp.2023-007, (Released:2023-07-15)

参考文献数

29

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This study aimed to determine the influence of surface roughness of the color adjustment potential restoration of universal resin composites. A structural colored resin composite (Omnichroma, OC) and a pigment-employed universal shade resin composite (Beautifil Unishade, BU) were used. Each resin composite was placed in a cavity to determine its ability to match the color of artificial teeth. The surface of the resin composites was polished with #800- or #2000-grit SiC paper before performing color measurements. One-way analysis of variance and Tukey post hoc tests were performed (α=0.05). The color difference (ΔE*ab) ranged from 2.5–3.9 for OC and 1.8–8.7 for BU. OC has a more stable color adjustment than BU. The color adjustment potential of universal resin composites was affected by the surface roughness of the restorations.

著者

Abdullah KAMEL Toshiki YAMAZAKI Natsuko MURAKAMI Huaxin LYU Kohei KOMINE Amr BADR Gehan FEKRY Hidekazu TAKAHASHI Noriyuki WAKABAYASHI

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.42, no.3, pp.336-342, 2023-05-25 (Released:2023-05-30)

参考文献数

35

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This study aimed to evaluate the retentive force of polyetheretherketone (PEEK) and zirconia secondary crowns on ready-made titanium implant abutments (with height, diameter, and taper as 5.5 mm, 4.5 mm, and 6°, respectively) as the primary crown. PEEK, zirconia, and titanium secondary crowns were fabricated using a CAD/CAM system. Insertion and removal tests of secondary crowns on the primary crown were conducted for 2,000 cycles. The initial retentive forces recorded at the 100th cycle for PEEK, zirconia, and titanium were 13.0±7.9, 2.9±2.6, and 27.6±1.7 N, respectively. The retentive forces of PEEK and zirconia showed no significant difference among all cycles. However, the retentive force of the titanium used as a control decreased (20.3±2.8 N) significantly at the 2,000th cycle. Although the retentive force of PEEK was lower than that of titanium, it was within the range that can provide a suitable retentive force of 5 N for removable dental prostheses.