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  • 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.
    .

    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.
    .

    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

  • 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

  • The effect of curing conditions on the dentin bond strength of two dual-cure resin cements.
    .

    The effect of curing conditions on the dentin bond strength of two dual-cure resin cements.

    J Prosthodont Res. 2017 Jan 23;:

    Authors: Tagami A, Takahashi R, Nikaido T, Tagami J

    Abstract
    PURPOSE: The purpose of this study was to determine the effect of the curing condition (i.e., the curing mode and restoration thickness) on the tensile bond strength of a dual-cure resin cement applied to dentin.
    METHODS: Indirect composite resin disks (1, 2, and 3mm in thickness) were prepared. The irradiance of a halogen light curing unit through each disk was measured by a curing radiometer. A measurement was also taken for the condition with no disk. Following this, two dual-cure resin cements, Panavia F2.0 and Panavia V5, were polymerized in either dual-cure mode or self-cure mode to bond the composite resin disk to the flat dentin surface. The specimens were sectioned and subjected to a microtensile bond strength (μTBS) test after 24h of water storage. The data were statistically analyzed by two-way ANOVA followed with multiple comparisons by post-hoc Tukey’s test (α=0.05).
    RESULTS: The irradiance values [mW/cm(2)] measured through indirect composite resin disks were 600 (0mm), 200 (1mm), 90 (2mm), and not detected (3mm). Two-way ANOVA indicated that both the curing condition and the type of resin cement affected the μTBS (p<0.001). The μTBS results for Panavia V5 bonded to dentin were significantly higher than those of Panavia F2.0 bonded to dentin (p<0.05).
    CONCLUSIONS: The curing condition affected the tensile bond strength of the dual-cure resin cements to dentin. A newly developed resin cement, Panavia V5, showed higher dentin bonding than Panavia F2.0 in both dual- and self-cure modes.

    (28126243) – as supplied by publisher]

    Bibliography

  • Evaluation of resin infiltration on demineralized root surface: An in vitro study.
    .

    Evaluation of resin infiltration on demineralized root surface: An in vitro study.

    Dent Mater J. 2017 Jan 20;:

    Authors: Zhou Y, Matin K, Shimada Y, Sumi Y, Tagami J

    Abstract
    The aim of this study was to evaluate the effect of resin infiltration on root caries induced by Streptococcus mutans biofilms. Human premolar specimens were divided to 5 groups: negative control (NC), Clearfil SE Bond (SEB), Icon-etch120s+Icon-infiltrant (HA120), Icon-etch10s+Icon-infiltrant (HA10) and K-etchant10s+Icon-infiltrant (PA10). The resin penetration was observed by fluorescent microscope. Biofilm-induced demineralization was conducted again and observed by swept-source optical coherence tomography and confocal laser scanning microscope. The maximum resin penetration depth (PDmax), lesion depth increase (∆LD), frequency of cervical enamel loss and dentinoenamel junction separation length were measured and statistically analyzed. HA120 showed 138.00±49.25 µm PDmax that was significantly larger than PA10 and SEB (p<0.05). SEB created 136.58±64.73 µm coating layers. HA120 and SEB showed significantly lower ∆LD than NC (p<0.05). Resin infiltration with 120s-HCl pretreatment has got a good penetration ability and preventive effect on root caries, however, an additional risk factor of cervical enamel loss was identified.

    (28111390) – as supplied by publisher]

    Bibliography

  • The influence of elastic moduli of core materials on shear stress distributions at the adhesive interface in resin built-up teeth.
    .

    The influence of elastic moduli of core materials on shear stress distributions at the adhesive interface in resin built-up teeth.

    Dent Mater J. 2017 Jan 13;:

    Authors: Chiba A, Hatayama T, Kainose K, Nakajima M, Pashley DH, Wakabayashi N, Tagami J

    Abstract
    This study aimed to investigate shear stress distributions in resin built-up teeth using resin composites of varying elastic moduli (E), with or without fiber posts. Three-dimensional mathematical models of a root-filled mandibular premolar tooth were constructed. Resin post and cores were built-up with resin composites of three different E: 12,000, 18,000 and 24,000 MPa, with or without fiber posts. Finite element linear analysis was performed to calculate shear stress distributions at bonding interface between resin core and dentin. Regardless of fiber post insertion, the shear stress on the cervical surface of resin core decreased as the E of resin composites increased. Insertion of fiber posts increased the shear stress on the post surface of resin core, with increases in the E of resin composites. In conclusion, using resin core materials with higher E decreased the shear stress at cervical interface between resin core and dentin regardless of fiber post insertion.

    (28090032) – as supplied by publisher]

    Bibliography

  • Evaluation of sub-surface penetration and bonding durability of self-etching primer systems to Er:YAG laser treated cervical dentin.
    .

    Evaluation of sub-surface penetration and bonding durability of self-etching primer systems to Er:YAG laser treated cervical dentin.

    Dent Mater J. 2017 Jan 13;:

    Authors: He Z, Chen L, Shimada Y, Tagami J, Ruan S

    Abstract
    This study aimed to investigate self-etching bonding systems penetrating in sub-surface dentin layer after Er:YAG laser irradiation and micro-shear bonding durability over a period of 1 year. Dentin slices obtained from extracted human third molars were prepared. Two self-etching adhesive systems were evaluated: Clearfil SE Bond and Clearfil Tri-S Bond. Specimens were tested for micro-shear bond strength with one of the following treatments: Er:YAG laser irradiation and 600-grit silicon paper polishing at 24 h, 7 days, 6 months and 1 year. The adhesive interfaces between bonding agents and lased cervical dentin were studied. No hybrid layer could be observed for lased dentin. The slim resin tags could be seen penetrating through the lased subsurface layer. Bond strength to lased dentin after 6 months and 1 year were significantly decreased. (p<0.05).

    (28090034) – as supplied by publisher]

    Bibliography

  • Evaluation of sub-surface penetration and bonding durability of self-etching primer systems to Er:YAG laser treated cervical dentin.
    .

    Evaluation of sub-surface penetration and bonding durability of self-etching primer systems to Er:YAG laser treated cervical dentin.

    Dent Mater J. 2017 Jan 13;:

    Authors: He Z, Chen L, Shimada Y, Tagami J, Ruan S

    Abstract
    This study aimed to investigate self-etching bonding systems penetrating in sub-surface dentin layer after Er:YAG laser irradiation and micro-shear bonding durability over a period of 1 year. Dentin slices obtained from extracted human third molars were prepared. Two self-etching adhesive systems were evaluated: Clearfil SE Bond and Clearfil Tri-S Bond. Specimens were tested for micro-shear bond strength with one of the following treatments: Er:YAG laser irradiation and 600-grit silicon paper polishing at 24 h, 7 days, 6 months and 1 year. The adhesive interfaces between bonding agents and lased cervical dentin were studied. No hybrid layer could be observed for lased dentin. The slim resin tags could be seen penetrating through the lased subsurface layer. Bond strength to lased dentin after 6 months and 1 year were significantly decreased. (p<0.05).

    (28090034) – as supplied by publisher]

    Bibliography

  • The influence of elastic moduli of core materials on shear stress distributions at the adhesive interface in resin built-up teeth.
    .

    The influence of elastic moduli of core materials on shear stress distributions at the adhesive interface in resin built-up teeth.

    Dent Mater J. 2017 Jan 13;:

    Authors: Chiba A, Hatayama T, Kainose K, Nakajima M, Pashley DH, Wakabayashi N, Tagami J

    Abstract
    This study aimed to investigate shear stress distributions in resin built-up teeth using resin composites of varying elastic moduli (E), with or without fiber posts. Three-dimensional mathematical models of a root-filled mandibular premolar tooth were constructed. Resin post and cores were built-up with resin composites of three different E: 12,000, 18,000 and 24,000 MPa, with or without fiber posts. Finite element linear analysis was performed to calculate shear stress distributions at bonding interface between resin core and dentin. Regardless of fiber post insertion, the shear stress on the cervical surface of resin core decreased as the E of resin composites increased. Insertion of fiber posts increased the shear stress on the post surface of resin core, with increases in the E of resin composites. In conclusion, using resin core materials with higher E decreased the shear stress at cervical interface between resin core and dentin regardless of fiber post insertion.

    (28090032) – as supplied by publisher]

    Bibliography

  • A pilot study to assess the morphology and progression of non-carious cervical lesions.
    .

    A pilot study to assess the morphology and progression of non-carious cervical lesions.

    J Dent. 2016 Dec 09;:

    Authors: Sugita I, Nakashima S, Ikeda A, Burrow MF, Nikaido T, Kubo S, Tagami J, Sumi Y

    Abstract
    OBJECTIVE: This longitudinal pilot study aimed to morphologically and quantitatively investigate the progress of non-carious cervical lesions (NCCLs) by using swept-source optical coherence tomography (SS-OCT).
    METHODS: The samples examined comprised sets of NCCL epoxy resin replicas obtained from 10 lesions in 6 patients who attended annual dental visits over 4 or 5 years. SS-OCT images of the replicas were analyzed in terms of the maximum depth (Dmax) and corresponding vertical width (VW) – using an image analyzer to estimate progression of the NCCLs over time.
    RESULTS: It was found that differences between wedge- and saucer-shaped lesions were morphologically distinguished well by the OCT images. There were significant differences in dimensions among Dmax, VW and horizontal width (HW). HW was the largest and Dmax was the smallest. Although no significant differences in absolute values of annual progression rates were found among Dmax, VW and HW, the percentage increase in Dmax was significantly greater compared to VW and HW. The ratios of Dmax to corresponding VW ranged from 0.49 to 1.01 for the wedge-shaped lesions and from 0.13 to 0.44 for saucer-shaped lesions, respectively.
    CONCLUSIONS: The dimensional analysis demonstrated notable progression with large variations. The wedge-shaped lesions appeared to show greater Dmax values compared to the saucer-shaped lesions.
    CLINICAL SIGNIFICANCE: With respect to the depth, the wedge-shaped lesions may progress at a greater rate compared to the saucer-shaped lesions.

    (27956017) – as supplied by publisher]

    Bibliography

  • Three-Dimensional Analysis of Enamel Crack Behavior Using Optical Coherence Tomography.
    .

    Three-Dimensional Analysis of Enamel Crack Behavior Using Optical Coherence Tomography.

    J Dent Res. 2016 Nov 21;:

    Authors: Segarra MS, Shimada Y, Sadr A, Sumi Y, Tagami J

    Abstract
    The aim of this study was to nondestructively analyze enamel crack behavior on different areas of teeth using 3D swept source-optical coherence tomography (SS-OCT). Ten freshly extracted human teeth of each type on each arch (n = 80 teeth) were inspected for enamel crack patterns on functional, contact and nonfunctional, or noncontact areas using 3D SS-OCT. The predominant crack pattern for each location on each specimen was noted and analyzed. The OCT observations were validated by direct observations of sectioned specimens under confocal laser scanning microscopy (CLSM). Cracks appeared as bright lines with SS-OCT, with 3 crack patterns identified: Type I – superficial horizontal cracks; Type II – vertically (occluso-gingival) oriented cracks; and Type III – hybrid or complicated cracks, a combination of a Type I and Type III cracks, which may or may not be confluent with each other. Type II cracks were predominant on noncontacting surfaces of incisors and canines and nonfunctional cusps of posterior teeth. Type I and III cracks were predominant on the contacting surfaces of incisors, cusps of canines, and functional cusps of posterior teeth. Cracks originating from the dental-enamel junction and enamel tufts, crack deflections, and the initiation of new cracks within the enamel (internal cracks) were observed as bright areas. CLSM observations corroborated the SS-OCT findings. We found that crack pattern, tooth type, and the location of the crack on the tooth exhibited a strong correlation. We show that the use of 3D SS-OCT permits for the nondestructive 3D imaging and analysis of enamel crack behavior in whole human teeth in vitro. 3D SS-OCT possesses potential for use in clinical studies for the analysis of enamel crack behavior.

    (27872333) – as supplied by publisher]

    Bibliography

  • Effect of phytic acid etchant on resin-dentin bonding: Monomer penetration and stability of dentin collagen.
    .

    Effect of phytic acid etchant on resin-dentin bonding: Monomer penetration and stability of dentin collagen.

    J Prosthodont Res. 2016 Oct 21;:

    Authors: Kong K, Hiraishi N, Nassar M, Otsuki M, Yiu CK, Tagami J

    Abstract
    PURPOSE: Phytic acid (IP6) works well as an etchant in dentin bonding to remove the smear layer due to its acidity and chelating effect. This study compared the etching effect of IP6 with phosphoric acid (PA) and ethylenediaminetetraacetic acid (EDTA) on resin-dentin bond strength, micromorphology of the etched dentin surface and nanoleakage formation along resin-dentin interfaces and compared the protecting effect against collagen degradation.
    METHODS: Dentin disks and flat dentin surfaces were obtained from extracted human teeth. Specimens were etched with 35% PA (15s), 0.5M EDTA (30s) or 1% IP6 (30s). The surfaces and longitudinal sections of the etched dentin disks were observed using field emission scanning electron microscope (FE-SEM). An etch-and-rinse adhesive was used to create composite build up-specimens for microtensile bond strength (μTBS) testing and nanoleakage observation. To evaluate the effect on collagen degradation, demineralized bovine root dentin blocks were challenged with bacterial collagenase and then observed under light microscope.
    RESULTS: PA- and EDTA- treated groups showed significantly lower μTBS when compared to IP6-treated group. PA showed distinct nanoleakage and severe collagen degradation. Only slight nanoleakage was detected in IP6 group. IP6 showed better effect than EDTA in preventing collagen degradation induced by bacterial collagenase.
    CONCLUSIONS: IP6 effectively removed the smear layer and etched dentin, providing high bond strength values and causing minimal nanoleakage and slight collagen degradation.

    (27777071) – as supplied by publisher]

    Bibliography