10 research outputs found
An unexpected behavior of a patient after a diastema closure treatment
Bir diastema kapatma işlemi sonrasında hastanın beklenmeyen davranışıEstetik görünümden uzak dişlerin çözümünü bulmak ve estetik restorasyonlar yapmak yeni materyaller ve teknikler sayesinde artık çok kolaylaşmıştır. Hastaların en büyük estetik şikayetlerinden biri maksilla orta hat diasteması’dır. Labial frenulumdan konjenital sebeplere kadar pek çok farklı nedenlerden dolayı orta hat diasteması oluşabilir. Orta hat diastema tedavi tekniklerinden biri dişlerin kompozit materyali ile restore edilmesidir. Wax-up model üzerinde silikon anahtar hazırlanarak kompozit materyalle yapılmış diastema kapatma yöntemi pratik, basit, öngörülebilir ve uygun fiyatlı bir minimal invaziv tekniktir. Bu olgu sunumunda; restoratif diş hekimliğinde yaygın bir tedavi şekli olan diastema kapatma işleminin hastanın model üzerinde onayladığı ve bitim sonrasında da beğendiği restorasyonları daha sonrasında yaşadığı kararsızlık sebebiyle 2 gün içinde söktürtmesi anlatılmaktadır. 24 yaşındaki bayan hasta üst ön dişleri arasındaki ~4mm genişliğindeki diastema şikâyeti ile kliniğimize başvurmuştur. Planlanan tedavi hakkında gerekli bilgilendirmeler yapıldıktan sonra hastamız restorasyonları onayladığına dair onam formunu imzalamış ve tedavilere başlanmış ve nanohibrit kompozit materyal ile restorasyonlar tamamlanmıştır. Sonuç olarak, kararsız hastalarda invaziv bir işleme başlamadan önce, hastanın yeni yapılan restorasyonlara alışma süresi de göz önünde bulundurularak, başlangıç tedavisi olarak kompozit lamina veneerleri tercih etmek çok daha yerinde bir tedavi yöntemi olacaktır
Can different polymerization times affect the surface microhardness, water sorption, and water solubility of flowable composite resins?
This in vitro study evaluated and compared the effects of different polymerization times on the surface microhardness, water sorption, and water solubility of flowable composite resins. Three flowable composite resins [Es Flow (ESF), IGOS Flow (IGF), Estelite Flow Quick (EFQ)] were tested in this study. Each flowable composite resin (n = 7) was polymerized in a disc-shaped mould (1x10 mm) with an LED light-curing unit (D Light Pro) for two different times (20 and 40 sec.). The top surfaces of all specimens were polished (Sof-Lex). The surface microhardnesses of the flowable composite resins were measured with a Vickers HMV microhardness tester. Water sorption and water solubility were calculated according to the ISO 4049 standard. One-way ANOVA and post hoc Tamhane, Dunnett, and Tukey tests were used in the statistical analyses. Pearson’s and Spearman’s rho correlation tests were used to assess possible correlations between the different variables. The results were evaluated with a significance of p<0.05. In terms of microhardness, a significant difference was found between materials at the same polymerization times (p<0.05). All materials showed water sorption of less than 40 µg/mm3 and water solubility of less than 7.5 µg/mm3 by following ISO 4049. The correlations among surface microhardness, water sorption, and water solubility showed that the differences were determined by the materials and the polymerization times. The physical properties of all flowable composite resin materials were enhanced after polymerization for twice the time recommended by the manufacturers
The use of a liner under different bulk-fill resin composites: 3D GAP formation analysis by x-ray microcomputed tomography
Gap formation of composite resin restorations is a serious shortcoming in clinical practice. Polymerization shrinkage stress exceeds the tooth-restoration bond strength, and it causes bacterial infiltration within gaps between cavity walls and the restorative material. Thus, an intermediate liner application with a low elastic modulus has been advised to minimize polymerization shrinkage as well as gap formation. Objective: The purpose of this in vitro study was to assess gap formation volume in premolars restored with different bulk-fill composites, with and without a resin-modified glass-ionomer cement (RMGIC) liner, using x-ray micro-computed tomography (micro-CT). Methodology: Sixty extracted human maxillary premolars were divided into six groups according to bucco-palatal dimensions (n=10). Standardized Class II mesio-occluso-distal cavities were prepared. G-Premio Bond (GC Corp., Japan) was applied in the selective-etch mode. Teeth were restored with high-viscosity (Filtek Bulk Fill, 3M ESPE, USA)-FB, sonic-activated (SonicFill 2, Kerr, USA)-SF and low viscosity (Estelite Bulk Fill Flow, Tokuyama, Japan)-EB bulk-fill composites, with and without a liner (Ionoseal, Voco GmbH, Germany)-L. The specimens were subjected to 10,000 thermocycles (5-55°C) and 50,000 simulated chewing cycles (100 N). Gap formation based on the volume of black spaces at the tooth-restoration interface was quantified in mm3 using micro-computed tomography (SkyScan, Belgium), and analyses were performed. Data were analyzed using repeated-measures ANOVA and the Bonferroni correction test (p < 0.05). Results: The gap volume of all tested bulk-fill composites demonstrated that Group SF (1.581±0.773) had significantly higher values than Group EB (0.717±0.679). Regarding the use of a liner, a significant reduction in gap formation volume was observed only in Group SFL (0.927±0.630) compared with Group SF (1.581±0.773). Conclusion: It can be concluded that different types of bulk-fill composite resins affected gap formation volume. Low-viscosity bulk-fill composites exhibited better adaptation to cavity walls and less gap formation than did sonic-activated bulk-fill composites. The use of an RMGIC liner produced a significant reduction in gap formation volume for sonic-activated bulk-fill composites
Evaluating the effects of different beverages with daily consumption habits on the wear of restorative materials
The aim of this study was to investigate the cumulative effects of fruit juices and/or alcoholic beverages on wear track area of the restorative materials by simulating the oral environment in vitro. A microhybrid, a sub-microhybrid, a nanofill resin composite, and a giomer material were used. A daily exposure habits model was created to simulate consumption frequency of acidic and/or alcoholic beverages. Two-body wear tests were carried out using a reciprocating wear tester. ANOVA and Tukey's HSD tests were used for statistical analyses (p < 0.05). When considering experimental groups related to daily exposure habits, statistical difference was found between restorative materials in terms of wear track area (p < 0.01). Joint effect of rmaterial and exposure on wear track area was statistically significant (p < 0.01). Giomer was found to be more affected by acidic and alcoholic beverages. Microhybrid resin composites showed less wear than the other restorative materials. Cumulative effects of alcoholic beverages and fruit juice on wear track area of materials could be related to material's composition and frequency of consumption of acid or ethanol-containing beverages. Daily cumulative effect of acidic and alcoholic beverages was found to be stronger than only acidic fruit juice consumption in terms of wear track area. The plasticizing effect and the concentration of ethanol in the alcoholic beverages provided the basis for the increased wear track area on the restorative materials
The effects of nutritional habits on leucite-based ceramic repaired with nanohybrid composites
The purpose of the present in vitro study was to evaluate the effects of nutritional habits (various liquids) on the color change and early repair bond strength of a leucite-based ceramic repaired with different contents of nanohybrid composite resins currently used by the clinicians. Ninety-six IPS-Empress CAD ceramic samples were obtained with low-speed diamond saw. For all samples same repair method was performed. Samples were divided into groups according to four nanohybrid composite resins used as a repair material: Tetric-N-Ceram Bulk Fill, Filtek Z550, Clearfil-Majesty Esthetic, Bisco-Aelite Aesthetic Enamel (n = 24). Composite resins were applied on ceramic surface and polymerized (40 sec). After waiting for 24 h, samples were divided into three subgroups according to liquid types: pomegranate-flavored mineral water, salad dressing, and distilled water (n = 8). Before and after immersion the samples in the various liquids, color measurements were calculated (24 h). Then, shear bond strength was tested with an universal testing machine.For the statistical analyses two-way ANOVA, Tukey HSD, Spearman's correlation tests were used at a significance of p 0.05). When a composite resin is selected as a repair material, nutritional habits of the patient should be taken into consideration. Although hydrophilic monomer type of a composite material is a more predominant factor associated with color change, filler weight has the same predominant effect on shear-bond strength
Can Fiber Application Affect the Fracture Strength of Endodontically Treated Teeth Restored with a Low Viscosity Bulk-Fill Composite?
Objective. The aim of this study is to evaluate the effects of different fiber insertion techniques and thermomechanical aging on the fracture resistance of endodontically treated mandibular premolar teeth restored using bulk-fill composites. Materials and Methods. Eighty human mandibular premolar teeth were randomly divided into eight groups: Group IN, Group BF, Group PRF1, Group PRF2, Group IN-TMA, Group BF-TMA, Group PRF1-TMA ,and Group PRF2-TMA. Group IN (intact) and Group IN-TMA (intact but subjected to thermomechanical aging) served as control groups. In the other six groups, endodontic treatment was performed and standardized mesio-occluso-distal (MOD) cavities were prepared. In BF, PRF1, and PRF2, the cavities were restored with bulk-fill composite only, bulk-fill/Ribbond, and bulk-fill/additional Ribbond, respectively. In BF-TMA, PRF1-TMA, and PRF2-TMA, the teeth were subjected to thermomechanical aging after the restorations. All of the teeth were fractured on the universal testing machine. Fracture surfaces were analyzed with a stereomicroscope. Results. Control groups showed significantly higher fracture strengths than tested groups (P0.05). Most of the favorable fractures were seen in PRF1, PRF2, and PRF2-TMA. Most of the unfavorable fractures were seen in BF-TMA. Conclusions. Although fiber insertion with different techniques did not increase the fracture strength of teeth restored with bulk-fill composites, it increased the favorable fracture modes. Thermomechanical aging did not change the fracture strength of the groups
Can Fiber Application Affect the Fracture Strength of Endodontically Treated Teeth Restored with a Low Viscosity Bulk-Fill Composite?
Objective. The aim of this study is to evaluate the effects of different
fiber insertion techniques and thermomechanical aging on the fracture
resistance of endodontically treated mandibular premolar teeth restored
using bulk-fill composites. Materials and Methods. Eighty human
mandibular premolar teeth were randomly divided into eight groups: Group
IN, Group BF, Group PRF1, Group PRF2, Group IN-TMA, Group BF-TMA, Group
PRF1-TMA ,and Group PRF2-TMA. Group IN (intact) and Group IN-TMA (intact
but subjected to thermomechanical aging) served as control groups. In
the other six groups, endodontic treatment was performed and
standardized mesio-occluso-distal (MOD) cavities were prepared. In BF,
PRF1, and PRF2, the cavities were restored with bulk-fill composite
only, bulk-fill/Ribbond, and bulk-fill/additional Ribbond, respectively.
In BF-TMA, PRF1-TMA, and PRF2-TMA, the teeth were subjected to
thermomechanical aging after the restorations. All of the teeth were
fractured on the universal testing machine. Fracture surfaces were
analyzed with a stereomicroscope. Results. Control groups showed
significantly higher fracture strengths than tested groups (P<0.05). No
statistically significant difference was observed among the tested
groups (P>0.05). Most of the favorable fractures were seen in PRF1,
PRF2, and PRF2-TMA. Most of the unfavorable fractures were seen in
BF-TMA. Conclusions. Although fiber insertion with different techniques
did not increase the fracture strength of teeth restored with bulk-fill
composites, it increased the favorable fracture modes. Thermomechanical
aging did not change the fracture strength of the groups