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  • Comparison of resin-based and glass ionomer sealants with regard to fluoriderelease and anti-demineralization efficacy on adjacent unsealed enamel.
    .

    Comparison of resin-based and glass ionomer sealants with regard to fluoriderelease and anti-demineralization efficacy on adjacent unsealed enamel.

    Dent Mater J. 2017 Sep 28;:

    Authors: Ei TZ, Shimada Y, Nakashima S, Romero MJRH, Sumi Y, Tagami J

    Abstract
    This study compared resin-based and glass ionomer sealants with regard to their fluoride-release behavior and anti-demineralization potential on adjacent unsealed enamel surfaces. Sealant cavities prepared on bovine enamel blocks were filled with fluoride-containing resin sealants [TeethmateF-1 (TF), Clinpro(TM) (CP)], and glass ionomer sealant [Fuji VII (FVII)]. Specimens were then incubated in artificial saliva for 14 days to measure fluoride. Thereafter, demineralization was performed for 10 days, and the anti-demineralization efficacy was assessed by Swept Source Optical Coherence Tomography (SS-OCT), and cross-sectional nanohardness. All data were statistically analyzed by using ANOVA. FVII exhibited the highest fluoride release. SS-OCT and nanohardness findings indicated that anti-demineralization efficacy of TF was the greatest, whereas FVII was not significantly different from that of CP. Resin sealants released a lower amount of fluoride but exhibited anti-demineralization effects on the adjacent unsealed enamel surfaces that were comparable to that of a glass ionomer sealant.

    (28954939) – as supplied by publisher]

    Bibliography

  • Microtensile Bond Strength of Resin-Modified Glass Ionomer Cement to Sound and Artificial Caries-Affected Root Dentin With Different Conditioning.

    Microtensile Bond Strength of Resin-Modified Glass Ionomer Cement to Sound and Artificial Caries-Affected Root Dentin With Different Conditioning.

    Oper Dent. 2017 Aug 31;:

    Authors: Saad A, Inoue G, Nikaido T, Ikeda M, Burrow MF, Tagami J

    Abstract
    In this laboratory study, the microtensile bond strengths (μTBS) of resin-modified glass ionomer cement (RM-GIC) to sound and artificial caries-affected bovine root dentin (ACAD) using three different conditioning agents were evaluated after 24 hours and three months. The fractured interface was examined with a scanning electron microscope (SEM). Specimens were created on bovine root dentin that was embedded in epoxy resin. For the ACAD specimens, artificial carious lesions were created. The RM-GIC (Fuji II LC) was applied either directly (no treatment), after application of self conditioner, cavity conditioner, or 17% ethylenediamine tetraacetic acid (EDTA) applied for 60 seconds, on sound dentin and ACAD, then light cured. They were stored in artificial saliva for 24 hours or three months. Following this, the specimens were cut into sticks for the μTBS test, and the failure mode of the debonded specimens was examined by using SEM. Pretest failures were excluded from the statistical analysis of the μTBS values because of their high incidence in some groups. Results showed that the μTBS values were significantly affected by the dentin substrate as well as the conditioning agent. Self conditioner provided the highest and most stable μTBS values, while cavity conditioner showed stable μTBS values on sound dentin. Both self conditioner and cavity conditioner had significantly higher μTBS values than the no treatment groups. EDTA conditioning reduced the μTBS after three months to sound dentin, while it showed 100% pretest failure with ACAD for both storage periods.

    (28857710) – as supplied by publisher]

    Bibliography

  • Microtensile Bond Strength of Resin-Modified Glass Ionomer Cement to Sound and Artificial Caries-Affected Root Dentin With Different Conditioning.

    Microtensile Bond Strength of Resin-Modified Glass Ionomer Cement to Sound and Artificial Caries-Affected Root Dentin With Different Conditioning.

    Oper Dent. 2017 Aug 31;:

    Authors: Saad A, Inoue G, Nikaido T, Ikeda M, Burrow MF, Tagami J

    Abstract
    In this laboratory study, the microtensile bond strengths (μTBS) of resin-modified glass ionomer cement (RM-GIC) to sound and artificial caries-affected bovine root dentin (ACAD) using three different conditioning agents were evaluated after 24 hours and three months. The fractured interface was examined with a scanning electron microscope (SEM). Specimens were created on bovine root dentin that was embedded in epoxy resin. For the ACAD specimens, artificial carious lesions were created. The RM-GIC (Fuji II LC) was applied either directly (no treatment), after application of self conditioner, cavity conditioner, or 17% ethylenediamine tetraacetic acid (EDTA) applied for 60 seconds, on sound dentin and ACAD, then light cured. They were stored in artificial saliva for 24 hours or three months. Following this, the specimens were cut into sticks for the μTBS test, and the failure mode of the debonded specimens was examined by using SEM. Pretest failures were excluded from the statistical analysis of the μTBS values because of their high incidence in some groups. Results showed that the μTBS values were significantly affected by the dentin substrate as well as the conditioning agent. Self conditioner provided the highest and most stable μTBS values, while cavity conditioner showed stable μTBS values on sound dentin. Both self conditioner and cavity conditioner had significantly higher μTBS values than the no treatment groups. EDTA conditioning reduced the μTBS after three months to sound dentin, while it showed 100% pretest failure with ACAD for both storage periods.

    (28857710) – as supplied by publisher]

    Bibliography

  • Adhesion Evaluation of Dentin Sealing, Micropermeability, and Bond Strength of Current HEMA-free Adhesives to Dentin.
    .

    Adhesion Evaluation of Dentin Sealing, Micropermeability, and Bond Strength of Current HEMA-free Adhesives to Dentin.

    J Adhes Dent. 2017 Aug 28;:1-8

    Authors: Bacelar-Sá R, Sauro S, Abuna G, Vitti R, Nikaido T, Tagami J, Ambrosano GMB, Giannini M

    Abstract
    PURPOSE: To evaluate dentin sealing (DS), micropermeability (MP), and dentin bond strength (BS) of HEMA-free adhesives after 24 h and one year of artificial saliva storage.
    MATERIALS AND METHODS: Two HEMA-free (G-ænial Bond and BeautiBond) and All-Bond 3 (the bottle of resin is HEMAfree) adhesives were tested. Adper Single Bond 2, a HEMA-containing adhesive, served as the control. All adhesives were applied according to the manufacturers’ instructions and teeth were prepared for DS (n = 5), MP (n = 5), and BS testing (n = 10). DS under a pulpal pressure of 10 psi was performed at 4 time points (when smear layer was present, after EDTA treatment, after adhesive application, and after 1 year). MP was assessed using pulpal pressure of a 20-cm aqueous dye-solution column and confocal laser scanning microscopy. DS, MP, and BS were performed after 24 h or one-year storage. BS and DS data were statistically analyzed using two-way ANOVA, the Tukey-Kramer test (for BS) and Tukey’s post-hoc test (for DS) (a = 0.05). A qualitative MP assessment was performed by comparing the accumulation of yellow dye within the resin-dentin interface.
    RESULTS: Adper Single Bond 2 and All-Bond 3 completely sealed the dentin at 24 h and one year. G-ænial Bond showed statistically significant DS reduction of approximately 15% after one year. BeautiBond showed no DS reduction after one year. The resin-dentin interface created using Adper Single Bond 2 and GA showed dye accumulation primarily after one year. The mean BS of All-Bond 3 was statistically significantly higher than that of other adhesives, while G-ænial Bond and BeautiBond showed statistically significantly lower mean bond strengths than did Adper Single Bond 2 and All-Bond 3. After one-year storage, the mean BS was statistically significantly lower only for G-ænial Bond.
    CONCLUSION: DS, MP, and BS were not influenced by the absence of HEMA in the tested adhesives.

    (28849795) – as supplied by publisher]

    Bibliography

  • µCT-3D visualization analysis of resin composite polymerization and dye penetration test of composite adaptation.
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    µCT-3D visualization analysis of resin composite polymerization and dye penetration test of composite adaptation.

    Dent Mater J. 2017 Aug 25;:

    Authors: Yoshikawa T, Sadr A, Tagami J

    Abstract
    This study evaluated the effects of the light curing methods and resin composite composition on composite polymerization contraction behavior and resin composite adaptation to the cavity wall using μCT-3D visualization analysis and dye penetration test. Cylindrical cavities were restored using Clearfil tri-S Bond ND Quick adhesive and filled with Clearfil AP-X or Clearfil Photo Bright composite. The composites were cured using the conventional or the slow-start curing method. The light-cured resin composite, which had increased contrast ratio during polymerization, improved adaptation to the cavity wall using the slow-start curing method. In the μCT-3D visualization method, the slow-start curing method reduced polymerization shrinkage volume of resin composite restoration to half of that produced by the conventional curing method in the cavity with adhesive for both composites. Moreover, μCT-3D visualization method can be used to detect and analyze resin composite polymerization contraction behavior and shrinkage volume as 3D image in the cavity.

    (28845034) – as supplied by publisher]

    Bibliography

  • Effect of a calcium phosphate and fluoride paste on prevention of enamel demineralization.
    .

    Effect of a calcium phosphate and fluoride paste on prevention of enamel demineralization.

    Dent Mater J. 2017 Aug 24;:

    Authors: Nakata T, Kitasako Y, Sadr A, Nakashima S, Tagami J

    Abstract
    This study aimed to examine the anti-demineralization capacities of (a) tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA) and 950 ppm fluoride paste, (b) casein phosphopeptide amorphous calcium phosphate paste and (c) 950 ppm fluoride solution using optical coherence tomography (OCT). Enamel blocks were cut from the bovine incisors and treated using one of the above-mentioned three materials or deionized water as control (n=10). All samples were subjected to a demineralization gel for 1 h followed by a remineralization solution for 23 h. This experimental cycle was repeated for 28 days. The specimens were imaged using OCT at baseline and at four stages and measured lesion depth using image analysis software (ImageJ). Repeated measures ANOVA revealed that demineralization time, material and their interaction significantly affected the optical lesion depth (p<0.001). TTCP and DCPA and 950 ppm fluoride paste and 950 ppm fluoride solution showed significantly lower lesion progress compare to other groups (p<0.05).

    (28835599) – as supplied by publisher]

    Bibliography

  • Effect of a calcium phosphate and fluoride paste on prevention of enamel demineralization.
    .

    Effect of a calcium phosphate and fluoride paste on prevention of enamel demineralization.

    Dent Mater J. 2017 Aug 24;:

    Authors: Nakata T, Kitasako Y, Sadr A, Nakashima S, Tagami J

    Abstract
    This study aimed to examine the anti-demineralization capacities of (a) tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA) and 950 ppm fluoride paste, (b) casein phosphopeptide amorphous calcium phosphate paste and (c) 950 ppm fluoride solution using optical coherence tomography (OCT). Enamel blocks were cut from the bovine incisors and treated using one of the above-mentioned three materials or deionized water as control (n=10). All samples were subjected to a demineralization gel for 1 h followed by a remineralization solution for 23 h. This experimental cycle was repeated for 28 days. The specimens were imaged using OCT at baseline and at four stages and measured lesion depth using image analysis software (ImageJ). Repeated measures ANOVA revealed that demineralization time, material and their interaction significantly affected the optical lesion depth (p<0.001). TTCP and DCPA and 950 ppm fluoride paste and 950 ppm fluoride solution showed significantly lower lesion progress compare to other groups (p<0.05).

    (28835599) – as supplied by publisher]

    Bibliography

  • Erosive Tooth Wear Among Different Tooth Types and Surfaces in Japanese Adults 15 to 89 Years Old.
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    Erosive Tooth Wear Among Different Tooth Types and Surfaces in Japanese Adults 15 to 89 Years Old.

    Oral Health Prev Dent. 2017 Jul 25;:357-364

    Authors: Kitasako Y, Sasaki Y, Takagaki T, Sadr A, Tagami J

    Abstract
    PURPOSE: To evaluate the prevalence of erosive tooth wear on buccal, incisal/occlusal and palatal/lingual surfaces in a wide age range of Japanese adults.
    MATERIALS AND METHODS: The study included a total of 1108 adults aged 15 to 89 years in Tokyo, Japan. The subjects were asked to complete a self-administered nutrition-related questionnaire. Two examiners evaluated tooth wear on the buccal, occlusal/incisal and palatal/lingual surfaces in a full-mouth recording, using a modified Smith and Knight tooth-wear index. Subjects who frequently consumed acidic beverages or food, or had gastric reflux and at least one tooth with an initial enamel smooth-surface wear facet were placed in an erosion-positive group, and the rest of subjects were placed in the erosion-negative group.
    RESULTS: 26.1% of the participants were placed in the erosion-positive group. For buccal surfaces, advanced wear progression was predominantly observed on maxillary and mandibular anterior teeth, especially in the youngest age group (15-39 years). On incisal/occlusal surfaces, early dentin exposure was observed in the middle age group (40-49 years) in the erosion-positive group. For palatal/lingual surfaces, wear progression was mainly observed on maxillary anterior teeth among 30- to 39-year olds and 50- to 59-year-old in the erosion-positive group, but that prevalence was lower than for the other tooth surfaces.
    CONCLUSIONS: For all age groups of Japanese adults, the prevalence of erosive tooth wear depended on tooth types and surfaces.

    (28748234) – as supplied by publisher]

    Bibliography

  • The effect of five kinds of surface treatment agents on the bond strength to various ceramics with thermocycle aging.
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    The effect of five kinds of surface treatment agents on the bond strength to various ceramics with thermocycle aging.

    Dent Mater J. 2017 Jul 12;:

    Authors: Noda Y, Nakajima M, Takahashi M, Mamanee T, Hosaka K, Takagaki T, Ikeda M, Foxton RM, Tagami J

    Abstract
    This study evaluated the effects of ceramic surface treatment agents on shear bond strengths to ceramic materials with and without thermocycling. Ceramic plates were prepared from feldspathic ceramic; AAA, lithium disilicate ceramic material; IPS e.max Press, zirconia ceramic; Lava. Ceramic surfaces were pretreated with one of five surface treatment agents (Clearfil PhotoBond mixed with Porcelainbond activator (PB), Clearfil SE One mixed with Porcelainbond activator (SO), Ceramic Primer (CP), Universal Primer (UP), Scotchbond Universal (SU)), and then a resin cement (Clapearl DC) was filled. After 0, 5,000, and 10,000 thermocycles, micro-shear bond strengths between ceramic-cement interfaces were determined. SU exhibited significantly lower initial bond strength to AAA and e.max than PB, SO, CP, and UP. For Lava, PB, SO, CP and SU exhibited higher initial bond strengths than UP. Thermocycles reduced bond strengths to all the ceramic materials with any surface treatment.

    (28701640) – as supplied by publisher]

    Bibliography

  • Mechanical properties and molecular structure analysis of subsurface dentin after Er:YAG laser irradiation.

    Mechanical properties and molecular structure analysis of subsurface dentin after Er:YAG laser irradiation.

    J Mech Behav Biomed Mater. 2017 Jun 03;74:274-282

    Authors: He Z, Chen L, Hu X, Shimada Y, Otsuki M, Tagami J, Ruan S

    Abstract
    The purpose of this study was to evaluate the chemical and mechanical modifications in subsurface dentin layer after Er: YAG (Erbium-Yttrium Aluminium Garnet) laser irradiation, as the guidance of new dental restorative materials specific for laser irradiated dentin.
    MATERIALS AND METHODS: Dentin disks obtained from extracted human molars were prepared and exposed to a single pulse Er:YAG laser irradiation at 80mJ/pulse. After laser irradiation the mechanical and chemical characteristics of intertubular dentin in subsurface layer were studied using nanoindentation tester and micro-Raman spectromy (μ-RS). The dentin 5-50µm depth beneath the lased surface was determined as testing area. Two-way analysis of variance (ANOVA) were used to compare the mechanical values between lased and untreated subsurface dentin (P = 0.05).
    RESULTS: A laser affected subsurface dentin layer after Er:YAG laser treatment is present. The laser irradiation is considered to decrease the mechanical properties in the superficial subsurface layer (<15µm deep). There was no significant difference in nanohardness and Young’s modulus between lased subsurface dentin and untreated dentin (p > 0.05) under the depth of 15µm. However, the dentin at 5µm and 10µm depth beneath the lased surface exhibited significantly lower (~ 47.8% and ~ 33.6% respectively) hardness (p < 0.05). Er:YAG laser irradiation affected both mineral and organic components in subsurface dentin layer, a higher degree of crystallinity and reduced organic compounds occurred in the lased subsurface dentin.
    CONCLUSION: Under the tested laser parameters, Er:YAG laser irradiation causes lower mechanical values and reduction of organic components in subsurface dentin, which has deleterious effects on resin adhesion to this area.

    (28646753) – as supplied by publisher]

    Bibliography

  • Bonding Durability of a Self-etch Adhesive to Normal Versus Smear-layer Deproteinized Dentin: Effect of a Reducing Agent and Plant-extract Antioxidant.

    Bonding Durability of a Self-etch Adhesive to Normal Versus Smear-layer Deproteinized Dentin: Effect of a Reducing Agent and Plant-extract Antioxidant.

    J Adhes Dent. 2017 Jun 02;:1-6

    Authors: Prasansuttiporn T, Thanatvarakorn O, Tagami J, Foxton RM, Nakajima M

    Abstract
    PURPOSE: To evaluate the effect of a reducing agent and plant-extract antioxidant on the bonding durability of a selfetch adhesive to normal and NaOCl-treated, smear-layer-deproteinized dentin.
    MATERIALS AND METHODS: Flat smear-layer-covered dentin surfaces from 60 extracted human molars were prepared by removing the occlusal enamel. The teeth were divided into two groups with or without NaOCl-deproteinizing treatment for 30 s, and further divided into three subgroups as follows: no application of antioxidant, application of Accel (p-toluenesulfinic acid sodium salt solution) for 5 s, or application of rosmarinic acid solution for 5 s. All treated dentin surfaces were bonded with a two-step self-etch adhesive (Clearfil SE Bond) and restored with composite (Clearfil AP-X). The bonded teeth were sectioned into a hourglass-shaped sticks with a composite-dentin bonded interface area of 1.0 mm2. After storage in artificial saliva for 24 h or 1 year, the specimens were subjected to the microtensile bond strength test (n = 15). Data were statistically analyzed with three-way ANOVA, Tukey’s post-hoc test, and the t-test (p < 0.05).
    RESULTS: Without an antioxidant, 1-year storage significantly reduced the bond strengths of the self-etch adhesive to normal and smear-layer-deproteinized dentin compared with those after 24-h storage (p < 0.05). Application of Accel and rosmarinic acid restored the compromised initial bond strengths to smear-layer-deproteinized dentin (p < 0.05), and prevented long-term deterioration of bond strengths to both normal and smear-layer-deproteinized dentin (p > 0.05).
    CONCLUSION: Application of Accel and rosmarinic acid improved bonding durability of the self-etch adhesive to both normal and smear-layer-deproteinized dentin.

    (28580461) – as supplied by publisher]

    Bibliography

  • Bonding Durability of a Self-etch Adhesive to Normal Versus Smear-layer Deproteinized Dentin: Effect of a Reducing Agent and Plant-extract Antioxidant.

    Bonding Durability of a Self-etch Adhesive to Normal Versus Smear-layer Deproteinized Dentin: Effect of a Reducing Agent and Plant-extract Antioxidant.

    J Adhes Dent. 2017 Jun 02;:1-6

    Authors: Prasansuttiporn T, Thanatvarakorn O, Tagami J, Foxton RM, Nakajima M

    Abstract
    PURPOSE: To evaluate the effect of a reducing agent and plant-extract antioxidant on the bonding durability of a selfetch adhesive to normal and NaOCl-treated, smear-layer-deproteinized dentin.
    MATERIALS AND METHODS: Flat smear-layer-covered dentin surfaces from 60 extracted human molars were prepared by removing the occlusal enamel. The teeth were divided into two groups with or without NaOCl-deproteinizing treatment for 30 s, and further divided into three subgroups as follows: no application of antioxidant, application of Accel (p-toluenesulfinic acid sodium salt solution) for 5 s, or application of rosmarinic acid solution for 5 s. All treated dentin surfaces were bonded with a two-step self-etch adhesive (Clearfil SE Bond) and restored with composite (Clearfil AP-X). The bonded teeth were sectioned into a hourglass-shaped sticks with a composite-dentin bonded interface area of 1.0 mm2. After storage in artificial saliva for 24 h or 1 year, the specimens were subjected to the microtensile bond strength test (n = 15). Data were statistically analyzed with three-way ANOVA, Tukey’s post-hoc test, and the t-test (p < 0.05).
    RESULTS: Without an antioxidant, 1-year storage significantly reduced the bond strengths of the self-etch adhesive to normal and smear-layer-deproteinized dentin compared with those after 24-h storage (p < 0.05). Application of Accel and rosmarinic acid restored the compromised initial bond strengths to smear-layer-deproteinized dentin (p < 0.05), and prevented long-term deterioration of bond strengths to both normal and smear-layer-deproteinized dentin (p > 0.05).
    CONCLUSION: Application of Accel and rosmarinic acid improved bonding durability of the self-etch adhesive to both normal and smear-layer-deproteinized dentin.

    (28580461) – as supplied by publisher]

    Bibliography

  • Morphological evaluation of artificial caries-affected dentin after applying FCP-COMPLEX.
    .

    Morphological evaluation of artificial caries-affected dentin after applying FCP-COMPLEX.

    J Oral Sci. 2017 May 19;:

    Authors: Mashiko R, Inoue G, Nikaido T, Tagami J

    Abstract
    FCP-COMPLEX is a newly-developed solution that contains fluoride, calcium, and phosphoric acid. It has the potential to reinforce caries-affected dentin. The purpose of this study was to evaluate the effect of FCP-COMPLEX on the morphology of bovine artificial caries-affected dentin (ACAD). FCP-COMPLEX, 2% sodium fluoride solution, and distilled water were applied to bovine ACAD and the effect on acid-induced damage was observed. Scanning electron microscopy was used to evaluate morphology after acid application. Energy dispersive X-ray spectroscopy was used for mapping and quantitative analyses of the dentin surface, and for line analysis of dentin-adhesive interface. The FCP-COMPLEX precipitated on the dentin surface and fluoride, calcium, and phosphorus were detected at a higher level in the FCP-COMPLEX group. The area of acid damage in caries-affected dentin was reduced by FCP-COMPLEX. In conclusion, FCP-COMPLEX significantly increased the deposition of fluoride onto bovine ACAD and inhibited demineralization.

    (28529278) – as supplied by publisher]

    Bibliography

  • Morphological evaluation of artificial caries-affected dentin after applying FCP-COMPLEX.
    .

    Morphological evaluation of artificial caries-affected dentin after applying FCP-COMPLEX.

    J Oral Sci. 2017 May 19;:

    Authors: Mashiko R, Inoue G, Nikaido T, Tagami J

    Abstract
    FCP-COMPLEX is a newly-developed solution that contains fluoride, calcium, and phosphoric acid. It has the potential to reinforce caries-affected dentin. The purpose of this study was to evaluate the effect of FCP-COMPLEX on the morphology of bovine artificial caries-affected dentin (ACAD). FCP-COMPLEX, 2% sodium fluoride solution, and distilled water were applied to bovine ACAD and the effect on acid-induced damage was observed. Scanning electron microscopy was used to evaluate morphology after acid application. Energy dispersive X-ray spectroscopy was used for mapping and quantitative analyses of the dentin surface, and for line analysis of dentin-adhesive interface. The FCP-COMPLEX precipitated on the dentin surface and fluoride, calcium, and phosphorus were detected at a higher level in the FCP-COMPLEX group. The area of acid damage in caries-affected dentin was reduced by FCP-COMPLEX. In conclusion, FCP-COMPLEX significantly increased the deposition of fluoride onto bovine ACAD and inhibited demineralization.

    (28529278) – as supplied by publisher]

    Bibliography

  • Real-Time Imaging of Gap Progress during and after Composite Polymerization.
    .

    Real-Time Imaging of Gap Progress during and after Composite Polymerization.

    J Dent Res. 2017 May 01;:22034517709005

    Authors: Hayashi J, Shimada Y, Tagami J, Sumi Y, Sadr A

    Abstract
    The aims of this study were to observe the behavior of composite and formation of gaps during and immediately after light polymerization using swept source optical coherence tomography (OCT) and to compare the interfacial integrity of adhesives in cavities through 3-dimensional (3D) image analysis. Forty tapered cylindrical cavities (4-mm diameter, 2-mm depth) were prepared in bovine incisors and restored using Bond Force (BF), Scotchbond Universal Adhesive (SBU), OptiBond XTR (XTR), or Clearfil SE Bond 2 (SE2), followed by Estelite Flow Quick flowable composite. Real-time imaging was performed at the center of restoration by the OCT system (laser center wavelength: 1,330 nm; frequency: 30 KHz) during and up to 10 min after light curing. The 3D scanning was performed 0, 1, 3, 5, and 10 min after light curing. The percentages of sealed enamel and dentin interface area (E%, D%) were calculated using Amira software. In real-time videos, the initial gaps appeared as a bright scattered area mainly on dentin floor and rapidly progressed along the cavity floor. The timing, rate, and extent of gap formation were different among the specimens. From 3D visualization, gap progress could be seen on both enamel and dentin even after irradiation; furthermore, typical toroidal gap patterns appeared at the dentin floor of BF and SBU. XTR and SE2 showed nearly perfect sealing performance on the dentin floor up to the 10 min that images were recorded. From quantitative analysis, SE2 and XTR showed significantly higher E% and D% than other groups. SBU showed the smallest E% and BF showed a significantly smaller D% than other groups ( P < 0.05). In conclusion, real-time observation of composite placement and 3D quantification of interfacial gaps were implemented within the experimental limitations. Interfacial gap formation during polymerization of the composite depended on the adhesive system used. The formed gaps continued to propagate after composite light curing finished.

    (28521113) – as supplied by publisher]

    Bibliography

  • Real-Time Imaging of Gap Progress during and after Composite Polymerization.
    .

    Real-Time Imaging of Gap Progress during and after Composite Polymerization.

    J Dent Res. 2017 May 01;:22034517709005

    Authors: Hayashi J, Shimada Y, Tagami J, Sumi Y, Sadr A

    Abstract
    The aims of this study were to observe the behavior of composite and formation of gaps during and immediately after light polymerization using swept source optical coherence tomography (OCT) and to compare the interfacial integrity of adhesives in cavities through 3-dimensional (3D) image analysis. Forty tapered cylindrical cavities (4-mm diameter, 2-mm depth) were prepared in bovine incisors and restored using Bond Force (BF), Scotchbond Universal Adhesive (SBU), OptiBond XTR (XTR), or Clearfil SE Bond 2 (SE2), followed by Estelite Flow Quick flowable composite. Real-time imaging was performed at the center of restoration by the OCT system (laser center wavelength: 1,330 nm; frequency: 30 KHz) during and up to 10 min after light curing. The 3D scanning was performed 0, 1, 3, 5, and 10 min after light curing. The percentages of sealed enamel and dentin interface area (E%, D%) were calculated using Amira software. In real-time videos, the initial gaps appeared as a bright scattered area mainly on dentin floor and rapidly progressed along the cavity floor. The timing, rate, and extent of gap formation were different among the specimens. From 3D visualization, gap progress could be seen on both enamel and dentin even after irradiation; furthermore, typical toroidal gap patterns appeared at the dentin floor of BF and SBU. XTR and SE2 showed nearly perfect sealing performance on the dentin floor up to the 10 min that images were recorded. From quantitative analysis, SE2 and XTR showed significantly higher E% and D% than other groups. SBU showed the smallest E% and BF showed a significantly smaller D% than other groups ( P < 0.05). In conclusion, real-time observation of composite placement and 3D quantification of interfacial gaps were implemented within the experimental limitations. Interfacial gap formation during polymerization of the composite depended on the adhesive system used. The formed gaps continued to propagate after composite light curing finished.

    (28521113) – as supplied by publisher]

    Bibliography

  • Assessment of enamel cracks at adhesive cavosurface margin using three-dimensional swept-source optical coherence tomography.
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    Assessment of enamel cracks at adhesive cavosurface margin using three-dimensional swept-source optical coherence tomography.

    J Dent. 2017 Apr 19;:

    Authors: Tabata T, Shimada Y, Sadr A, Tagami J, Sumi Y

    Abstract
    OBJECTIVES: Swept-source optical coherence tomography (SS-OCT) can construct cross-sectional images of internal biological structures. The aim of this study was to evaluate enamel cracks at the cavosurface margin of composite restorations using SS-OCT.
    METHODS: Bowl-shaped cavities were prepared at two locations (mid-coronal and cervical regions) on the enamel surface of 60 bovine teeth. Half of the cavities (30) were treated with phosphoric acid gel. A two-step self-etch adhesive (Clearfil SE Bond) was applied to all cavities and a flowable composite was placed in bulk. After 7days in water at 37°C, three-dimensional (3D) images of the specimens were obtained using SS-OCT, and cross-sectional views of the cavosurface margin were examined. Presence and extent of enamel cracks along the cavosurface margin circumference were evaluated using a 5-point scale. The results were statistically compared with Wilcoxon rank sum test with Bonferroni correction.
    RESULTS: 3D SS-OCT could detect enamel cracks at the cavosurface margin of composite restorations. Cervical regions caused more enamel cracking than mid-coronal regions. Phosphoric acid etching increased the incidence of enamel cracks compared with the preparations without etching.
    CONCLUSION: SS-OCT can be used to detect enamel cracks at the margins of composite restorations noninvasively. Presence and extent of enamel cracks depended on the enamel region and bonding protocol.
    CLINICAL SIGNIFICANCE: SS-OCT can be used to detect enamel cracks at the margins of composite restorations noninvasively. Selective phosphoric acid etching of the enamel significantly increased the incidence of marginal cracks, especially in cervical preparation.

    (28433536) – as supplied by publisher]

    Bibliography

  • Effects of experimental pastes containing surface pre-reacted glass ionomer fillers on inhibition of enamel demineralization.
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    Effects of experimental pastes containing surface pre-reacted glass ionomer fillers on inhibition of enamel demineralization.

    Dent Mater J. 2017 Mar 29;:

    Authors: Nakamura K, Hamba H, Nakashima S, Sadr A, Nikaido T, Oikawa M, Uo M, Tagami J

    Abstract
    This study aimed to evaluate the inhibitory effect of experimental pastes containing surface pre-reacted glass ionomer (S-PRG) fillers on enamel demineralization. Bovine blocks were treated twice a day for 4 days by 7 groups; experimental pastes containing 0-30 wt% S-PRG filler (S00, S01, S05, S10, and S30), deionized water (DW) as negative control, and NaF paste (MP) as positive control. The surfaces were demineralized by acetic acid for 3 days. Mineral loss (ML) was calculated by micro-computed X-ray tomography. The treated surface was finally investigated with scanning electron microscope (SEM) and micro-focused particle induced X-ray emission (micro-PIXE). S05, S10 and S30 demonstrated significantly lower ML than S00, S01 and DW (p<0.05). S10 showed the greatest inhibitory effect, which was significantly greater than MP. The S-PRG filler containing experimental pastes demonstrated a potential to inhibit enamel demineralization. Sr ion incorporation was confirmed on the enamel surface with the experimental pastes.

    (28367910) – as supplied by publisher]

    Bibliography

  • Dentin Bonding Durability of Two-step Self-etch Adhesives with Improved of Degree of Conversion of Adhesive Resins.

    Dentin Bonding Durability of Two-step Self-etch Adhesives with Improved of Degree of Conversion of Adhesive Resins.

    J Adhes Dent. 2017 Feb 10;:

    Authors: Sato K, Hosaka K, Takahashi M, Ikeda M, Tian F, Komada W, Nakajima M, Foxton R, Nishitani Y, Pashley DH, Tagami J

    Abstract
    PURPOSE: To evaluate (1) the initial and long-term microtensile bond strengths of two-step self-etch adhesives with different degrees of conversion (DC); (2) the elastic modulus of the respective adhesive resins; (3) the water sorption of the respective adhesive resins.
    MATERIALS AND METHODS: Two two-step self-etch adhesives, Clearfil SE Bond (CSE) and Clearfil SE Bond 2 (CSE2) were used in this study. The DC was determined using ATR/FT-IR with a time-based spectrum analysis. Midcoronal flat dentin surfaces of 24 human molars were prepared with 600-grit SiC paper for microtensile bond strength (μTBS) testing. CSE and CSE2 were applied to the dentin surfaces according to the manufacturer’s instructions, followed by composite buildups. The μTBS was measured after water storage for 24 h, 6 months, and 1 year. The elastic modulus (before and after 1 month of water immersion) was determined by the three-point flexural bending test and water sorption values by the water sorption test.
    RESULTS: CSE2 showed significantly higher DC than CSE. The μTBS of CSE2 was significantly higher than that of CSE in all water storage periods. One-year water storage decreased the μTBS of CSE; however, it did not decrease that of CSE2. Regarding the polymerized adhesive resins, the elastic modulus of CSE2 was significantly higher than that of CSE before and after water immersion (p < 0.001), and the water sorption of CSE was higher than that of CSE2.
    CONCLUSIONS: The higher DC of adhesive resins of two-step self-etch adhesives resists water aging and improves the initial bond strengths and durability of the resin-dentin bond.

    (28195277) – as supplied by publisher]

    Bibliography

  • Multifactorial logistic regression analysis of factors associated with the incidence of erosive tooth wear among adults at different ages in Tokyo.
    .

    Multifactorial logistic regression analysis of factors associated with the incidence of erosive tooth wear among adults at different ages in Tokyo.

    Clin Oral Investig. 2017 Feb 07;:

    Authors: Kitasako Y, Sasaki Y, Takagaki T, Sadr A, Tagami J

    Abstract
    OBJECTIVES: The aim of this study was to evaluate factors associated with the incidence of erosive tooth wear (ETW) among adults at different ages in Tokyo using multifactorial logistic regression analysis.
    MATERIALS AND METHODS: The study sample consisted of a total of 1108 subjects aged 15 to 89 years in Tokyo, Japan. Two examiners evaluated ETW in a full-mouth recording. The subjects were asked to complete a self-administered daily diet, habit, and health condition questionnaire. Subjects who had frequent acid consumption or gastric reflux and at least one tooth with initial enamel wear were placed in the ETW-positive group, and the remainder of the subjects was placed in the ETW-negative group. Logistic regression analyses were carried out to identify factors collectively associated with ETW.
    RESULTS: Logistic regression analysis showed that greater frequencies of carbonated or sports drink consumption were associated with higher incidence of ETW for all age groups except for 70-89 years. Adults in the 30-39-year group who reported suffering from heartburn were about 22.3 times more likely to develop ETW, while 40-49-year adults who had repeated vomiting were about 33.5 times more likely to exhibit ETW compared with those who did not experience vomiting.
    CONCLUSION: Age-specific dietary habits were clearly observed among adults at different ages in Tokyo, and there were significant differences in intrinsic and extrinsic factors between ETW-positive and ETW-negative groups for each age group.
    CLINICAL RELEVANCE: Both greater frequency of carbonated and sports drink consumption were associated with higher incidence of ETW among adults at different ages in Tokyo.

    (28176000) – as supplied by publisher]

    Bibliography