Yazar "Yoruç, Afife Binnaz Hazar" seçeneğine göre listele

Listeleniyor 1 - 6 / 6
  • [ X ]
    Öğe
    Development of biomimetic hydroxyapatite containing dental restorative composites
    (Springer, 2022) Aydınoğlu, Aysu; Türkcan, Julide Hazal; Keleşoğlu, Ergün; Yoruç, Afife Binnaz Hazar
    The aim of the study was to evaluate the incorporation effect of biomimetic hydroxyapatite (BHA) particles on the mechanical properties of experimental dental composites. Two experimental composites were produced from the same organic matrix, Si/Zr nanocluster, and SiO2/silane as main inorganic reinforcing fillers. 7wt% BHA was added to one of the groups to evaluate its effect on mechanical properties. The BHA was also modified with 3-MPTMS to improve chemical bonding. Chemical structures and physical properties of the fillers were identified by XRD, FTIR, XPS, TGA, SEM, BET, and Zeta-Sizer. According to ISO 4049 and DIN 50,133 the mechanical properties, and to ISO 10993-5:2009 the biocompatibility was investigated. Analysis of variance (ANOVA) was used for the statistical analysis of acquired data. The BHA was synthesized by the biomimetic method in simulated body media (SBF). The SEM images of BHA/Silane particles demonstrated rod-like shapes and similar dimensions with natural hydroxyapatite present in tooth enamel. The modification by using 3-MPTMS was decreased the mean particle size of the fillers due to a lower agglomeration tendency. Moreover, the addition of small mass fractions of the BHA into the dental resins can substantially meet the ISO 4049 requirements. Consequently, the BHA was not adversely decreasing the mechanical properties of the dental composites. Also, the biocompatibility of the BHA-containing composites was found better than the samples without BHA-containing composites. The incorporation of the BHA can meet the mechanical requirements of dental resins and composites. Additionally, it may show regenerative properties against small lesions.
  • Küçük Resim
    Öğe
    Effect of repolishing on the surface roughness and color stability of air-abraded resin composites
    (Original ArticleInternational Dental Research, 2022) Sağır, Kadir; Altaş, Nurcan; Aydınoğlu, Aydın; Çil, Burcu Gözeteci; Keleşoğlu, Ergün; Yoruç, Afife Binnaz Hazar
    Aim:Air powder polishing (APP) can cause roughness on composite surfaces, and consequently the color change that occurs over time affects the aesthetic negatively. Here, we aim to investigate the effect of repolishing on the roughness and discoloration of resin composites after APP to avoid its negative effects for the first time.Methodology:A total of 39 composite discs were randomly allocated into three groups: Group I: Control (n = 13), Group II: Air Powder Polished (n = 13), and Group III: Air Powder Polished + Re-polished (n = 13). Color and surface roughness of the discs were measured before and after immersion in coffee for 1 week. Color was measured using a colorimeter (CR-400, Konica Minolta, Osaka, Japan), and roughness was measured using a surface roughness analyzer (SJ-400, Mitutoyo, Japan).Results:All specimens in the groups, except those in Group III, showed significant changes in roughness, and all materials showed significant color changes after immersion in the coffee relative to the baseline. There was no statistically significant difference between the groups in terms of roughness and color.Conclusion:In this study, we showed that repolishing after APP does not significantly improve the color stability and roughness of the composite restorations.
  • [ X ]
    Öğe
    Effect of water absorption and hydroxyapatite addition on mechanical and microstructural properties of dental luting cements
    (Walter de Gruyter, 2022) Elibol, Çağatay; Atalay, Ender Gökşen; Sağır, Kadir; Yoruç, Afife Binnaz Hazar
    In recent years, dental cements have gained more and more importance due to the increasing clinical expectations. They are used as restorative materials and as materials providing critical functions such as chemical and physical adhesion in restorations and protective lining in the cavity. In this work, the effect of water absorption on the mechanical and microstructural properties of different commercial dental cements is systematically investigated. Furthermore, the effect of addition of biocompatible hydroxyapatite on the mechanical and microstructural properties of the cements is characterized. The results show that Voco Meron containing glass ionomer provides the highest values in water absorption and volume change tests. Ketac Cem Radiopaque (209 HV) containing glass ionomer exhibits the highest hardness increase after immersion for 28 days in water, whereas the highest water uptake value is observed in Adhesor Carbofine cement containing zinc polycarboxylate. The hardness of Adhesor ZincPhospate increases with increasing content of hydroxyapatite, whereas in Ketac Cem Radiopaque, the hardness decreases with increasing content of hydroxyapatite significantly. Test results are verified by microstructural analysis of different types of dental cements using scanning electron microscopy and the effect of particle size/distribution on the properties that are of crucial clinical importance is characterized in detail.
  • Küçük Resim
    Öğe
    In vitro bioactivity of laser surface-treated Ti6Al4V alloy
    (Springer, 2019) Yoruç, Afife Binnaz Hazar; Keleşoğlu, Ergün; Ekşioğlu Yıldız, Harika
    The effects of lasing parameters on the precipitation of hydroxyapatite (HA) on the commercial Ti6Al4Valloy in simulated body fluid (SBF) were investigated. Ti6Al4V plates were polished and ultrasonically cleaned in acetone and ethyl alcohol, respectively. The specimen surfaces were treated with Er:YAG laser using super short pulse (SSP, 50 ?s) and very short pulse (VSP, 100 ?s) modes. Surface roughness was measured before and after laser treatment. The specimens were immersed in simulated body fluid (SBF) for 1, 3, and 7 days and, then the amount of Ca and P precipitation on specimens was determined using SEM/ EDS analysis. An average roughness varying between 0.19 and 0.81 ?m in surface roughness was detected in all laser-treated specimens depending on the lasing parameters. The highest surface roughness and Ca precipitation were found in VSP group (20 Hz and 5 W). Laser treatment of specimen surfaces has dramatically increased the HA precipitation due to the increasing surface roughness. It is also concluded that the immersion time was effective on the HA precipitation as well.
  • Küçük Resim
    Öğe
    Influence of different irrigation solutions on the push-out bond strength of fiber posts to root dentin and root canal dentin microhardness: methodological study
    (Türkiye Klinikleri Diş Hekimliği Bilimleri Dergisi, 2023) Hepşenoğlu, Yelda Erdem; Erşahan, Şeyda; Yılmaz, Burcu; Aydınoğlu, Aysu; Sağır, Kadir; Yoruç, Afife Binnaz Hazar
    This study aimed to compare the effect of sodium hypochlorite (NaOCl), chlorhexidine (CHX), ethylene diamine tetra acetic acid (EDTA) and etidronic acid (HEBP) solutions and their combinations on a push-out bond strength of fiber posts to root canal dentin and on root dentin microhardness. Material and Methods: Sixty human maxillary central incisors were sectioned below the cementoenamel junction, the roots were endodontically treated and were divided into 6 groups (n=10) according to the final irrigation protocol: (1) Distilled water, (2) CHX, (3) HEBP-NaOCl combination, (4) HEBP, (5) 2.5 % NaOCl, (6) 17% EDTA. The fiber posts were then cemented with self-etching resin cement. Bonded specimens were cut (1-mm-thick), the first slice of the coronal 3rd was used for dentin microhardness analysis, and other slices were used for the push-out bond strength test. The data were statistically analyzed by using Shapiro-Wilk, Oneway ANOVA, and the Games-Howell test. Results: The lowest microhardness was observed in HEBP-NaOCl and NaOCl (p<0.05). CHX, HEBP, and EDTA resulted in less reduction in microhardness as compared to other groups (p<0.05). HEBP-NaOCl and NaOCl showed significantly higher mean bond strength to root dentin in the cervical thirds than in other groups (p<0.05). Conclusion: With regard to the push-out bond strength of the fiber post to dentin, NaOCl and HEBP-NaOCl increased bond strength compared to other groups. NaOCl and HEBP-NaOCl have lower microhardness of dentin. Compared to HEBP, EDTA increases microhardness and does not make a significant difference in push-out bond strength. Therefore, it is recommended to use HEBP alone.
  • Küçük Resim
    Öğe
    Nanoflower hydroxyapatite's effect on the properties of resin-based dental composite
    (Journal of Applied Polymer Science, 2024) Sağır, Kadir; Aydınoğlu, Aysu; Yoruç, Afife Binnaz Hazar
    To investigate the reinforcing effect of nanoflower-like hydroxyapatite (NFHA) inresin-based dental composites, we synthesized a novel NFHA using microwaveirradiation (MW), hydrothermal treatment (HT), and sonochemical synthesis (SS).Silanized NFHA was then used as the reinforcing filler in dental resin composites.We characterized the structure and morphology of various HA nanostructuresusing x-ray diffraction, scanning electron microscope, and TEM. The mechanicalperformance of dental resin compositesreinforced with silanized NFHA was mea-sured using a universal testing machine. Spherical HA, synthesized throughchemical precipitation (CP), served as the control group. One-way analysis of vari-ance was employed for the statistical analysis of the acquired data. The resultsdemonstrate that the nanoflower morphology significantly was improved mechan-ical and physical properties. After conducting trials, the NFHA synthesized usingMW and HT showed a substantial enhancement in mechanical and physicalproperties compared to the other structures. Therefore, it can be concluded thatNFHA can serve as a novel reinforcing HA filler, providing regenerative proper-ties to resin composites with sufficient mechanical strength.