Yazar "Veli, Ilknur" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Effects of different pre-treatment methods on the shear bond strength of orthodontic brackets to demineralized enamel
    (TAYLOR & FRANCIS LTD, 2016) Veli, Ilknur; Akin, Mehmet; Baka, Zeliha Muge; Uysal, Tancan
    Objective. To compare the effects of different treatment methods used for the enamel damage, on the shear bond strength (SBS) and fracture mode of orthodontic brackets. Materials and methods. Freshly-extracted 140 premolars were randomly allocated to seven groups: Group I was considered as the control of other groups. The remaining groups were exposed to demineralization. In group II, brackets were directly bonded to the demineralized enamel surface. CPP-ACP paste (GC Tooth Mousse), fluoride varnish (Bifluorid 12), microabrasion with a mixture prepared with 18% hydrochloric acid and fine pumice powder, microabrasion with an agent (Opalustre) and resin infiltrant (Icon (R)) were applied in Groups III, IV, V, VI and VII, respectively. The specimens were tested for SBS and bond failures were scored according to the Adhesive Remnant Index (ARI). Analysis of variance and Tukey tests were used to compare the SBS of the groups. ARI scores were compared with G-test. The statistical significance was set at p < 0.05 level. Results. Statistically significant differences were found among seven groups (F = 191.697; p < 0.001). The SBSs of groups I (mean = 18.8 +/- 2.0 MPa) and VII (mean = 19.1 +/- 1.4 MPa) were significantly higher than the other groups. No statistically significant difference was found between groups IV (mean = 11.5 +/- 1.2 MPa) and V (mean = 12.6 perpendicular to 1.5 MPa). The differences in ARI scores of the groups were statistically significant (p < 0.01). Conclusions. All demineralization treatment methods improve bonding to demineralized enamel. Resin infiltrant application after demineralization showed similar bond strength values as intact enamel.
  • Küçük Resim Yok
    Öğe
    Shear bond strength of a self-adhering flowable composite when used for lingual retainer bonding
    (URBAN & VOGEL, 2014) Veli, Ilknur; Akin, Mehmet; Kucukyilmaz, Ebru; Uysal, Tancan
    The goal of this work was to assess the shear bond strength (SBS) and fracture mode of a self-adhering flowable composite when used after thermocycling for lingual retainer bonding. A total of 80 human mandibular incisor teeth were categorized into four equal groups: group 1: Vertise (TM) Flow (VF) without acid etching; group 2: VF with acid etching; group 3: VF with a self-etching bonding agent accompanied by an additional acid etching; group 4: Transbond LR control. Either VF or Transbond LR was applied to the lingual surface of the teeth by packing the material into cylindrical plastic matrices to simulate the lingual retainer bonding area. After all teeth were thermocycled (5000 cycles, 5 and 55 A degrees C), fracture modes were examined under x20 magnification. The SBS data were assessed via analysis of variance (ANOVA) and Tukey's tests. Fracture modes were analyzed by the chi(2) test at a significance level of 0.05. Statistically significant differences in SBS values between groups (p < 0.001) were observed. Group 4 exhibited the highest (14.63 +/- 1.36 MPa) and group 1 the lowest SBS (2.67 +/- 1.35 MPa) values. Statistically significant differences were noted in fracture modes between groups 1, 3, and 4 (p < 0.001). In all the self-adhering flowable composite groups, the adhesive type (tooth-composite interface) fracture occurred more frequently than cohesive and mixed-type fractures. When applied to bond lingual retainers to unetched enamel or with self-etching bonding agent accompanied by an additional acid etching, Vertise (TM) Flow resulted in a significant decrease in bond strength.