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

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
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

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
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

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
Takaaki SATO Rena TAKAHASHI Shin ROZAN Saki UCHIYAMA Yuta BABA Martina VICHEVA Ayaka SATO Masaomi IKEDA Tomohiro TAKAGAKI Toru NIKAIDO 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.40, no.3, pp.719-726, 2021-05-25 (Released:2021-05-29)
参考文献数
34
被引用文献数
1 2

This study evaluated the effect of temporary sealing materials and cleaning protocols on the bond strength of resin cement applied to dentin using resin-coating technique. Scotchbond Universal Adhesive and Filtek Supreme Ultra Flowable were applied to bovine dentin. Forty-five specimens were divided into the following three groups according to the temporary sealing materials: Cav-: CAVITON EX, Vas-: COCOA BUTTER and FIT SEAL, and Sep-: Washable SEP and FIT SEAL. Each material was placed on resin-coated dentin. After 1-week water storage, one of the following three cleaning protocols was performed: -WA: washed with water, -BR: brushed with PRESSAGE, and -AF: cleaned with AIR-FLOW. Microtensile bond strength test and EDS analysis were conducted. Irrespective of the cleaning protocol used, Washable SEP demonstrated less residual debris on resin-coated dentin, resulting in high bond strength. Regardless of the temporary sealing material applied, AIR-FLOW demonstrated less residual debris, resulting in high bond strength.
著者
Wataru Komada Tasuku Inagaki Yoji Ueda Satoshi Omori Keiichi Hosaka Junji Tagami Hiroyuki Miura
出版者
Japan Prosthodontic Society
雑誌
Journal of Prosthodontic Research (ISSN:18831958)
巻号頁・発行日
vol.61, no.1, pp.73-80, 2017 (Released:2017-03-22)
参考文献数
26
被引用文献数
5

Purpose: The purpose of this study was to evaluate the influence of water immersion on the mechanical properties of three kinds of glass fiber posts and the fracture resistance of structures using resin composites with glass fiber posts.Methods: Each post was divided into three groups; a control group and two water immersion groups (30 and 90 days). Flexural strength was determined by three-point bending test. Each structure was divided into two groups; a control group and a water immersion group for 30 days. The fracture strength of structures was determined by a static loading test.Results: In the flexural strength, two kinds of post in water immersion groups showed lower values than control groups. In the fracture strength, two kinds of structures in water immersion group showed lower values than control groups.Conclusion: The prefabricated glass fiber posts and structures using resin composites with glass fiber posts were affected by water immersion.
著者
Toru NIKAIDO Tomohiro TAKAGAKI Takaaki SATO 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
pp.2020-165, (Released:2020-07-04)
参考文献数
40
被引用文献数
3 9

Self-etch adhesive (SEA) systems simplify bonding procedures. It is believed that good mechanical retention and chemical bonding are both important factors to obtain reliable bonding to enamel. The enamel acid-base resistant zone (ABRZ) has been confirmed at the adhesive/enamel interface by scanning electron microscopic observation. However, the formation of enamel ABRZ is influenced by the type and components of adhesive systems. Chemical interactions by a functional monomer with hydroxyapatite strongly support the explanation of the mechanism for enamel ABRZ formation. The ABRZ created by MDP-containing SEA systems has shown good potential to resist acid attack from simulated recurrent caries models. In addition, fluoride release may enhance acid resistance. It has been proposed that such a reinforced enamel be termed “Super Enamel”. The concept of the formation of super enamel may contribute to protecting enamel, and conserve tooth structure leading to improved restoration longevity.
著者
Akifumi TAKAHASHI Tomohiro TAKAGAKI Takahiro WADA Motohiro UO Toru NIKAIDO 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.37, no.5, pp.734-739, 2018-09-27 (Released:2018-09-30)
参考文献数
23
被引用文献数
20

The effects of contamination and cleaning methods on bonding of self-adhesive resin cement to zirconia ceramics were examined. Airborne particle-abraded zirconia (Zpex Smile) specimens were divided into the following four groups: control (con), contaminated with saliva and cleaned with tap water (HS), cleaned with Ivoclean (IC), and cleaned with Multi Etchant (ME). The pretreated specimens were bonded using three self-adhesive resin cements, and tensile bond strengths were measured using a universal testing machine at a crosshead speed of 2 mm/min. Con and IC groups showed significantly higher bond strength than those of HS and ME groups. Separately, the surface chemical composition of the groups was determined using X-ray photoelectron spectroscopy (XPS). XPS revealed that the N/Zr ratio increased in the HS group but decreased in the IC and ME groups. Cleaning agents can improve the adverse effect of saliva contamination on zirconia, but this effect varies depending on the product.