Effect of staining and bleaching on the microhardness, surface roughness and color of different composite resins

Background. There are studies that examined the effect of staining on the surface properties of composite resins, using different solutions and bleaching applications. However, the effect of both staining and bleaching on the same composite specimens is an issue that needs to be investigated. Objectives. The aim of this study was to investigate the surface microhardness, roughness and color changes (Delta E) of 2 different composite resins after staining and bleaching. Material and methods. A microhybrid and a nanohybrid composite were used in the study. One hundred and fifty specimens were prepared from each composite. The specimens were divided into 5 groups and stained for 30 days with tea, coffee, cola, red wine, or distilled water (control). Subsequently, each group was divided into 3 subgroups. Each subgroup received a 14-day application of Opalescence (TM) Boost, Opalescence PF or VivaStyle (R) Paint On Plus bleaching materials. The color as well as surface microhardness and roughness of all specimens were determined at baseline, after staining and after bleaching. Data was analyzed using the repeated-measures analysis of variance (ANOVA) and the Bonferroni method. Results. A statistically significant decrease was observed in the surface microhardness of the microhybrid composite specimens after bleaching (p < 0.05).The highest Delta E values were observed in the red wine groups for both composite resins. Conclusions. Staining and bleaching may affect surface properties and color, depending on the type, filler and matrix content of the composite resin

Effect of different polymerization type on water sorption and solubility of adhesive resın cements

incelenmesidir. Gereç ve yöntem: Mevcut çalışmada 2 farklı self-etch adeziv rezin siman (Duo-Link B, Clearfil Esthetic Cement C) ve 2 farklı self adeziv rezin siman (RelyX U200 Automix R, Maxcem Elite M) test edildi. Her bir adeziv rezin siman için 24 adet örnek hazırlandı ve kullanılan polimerizasyon yöntemine göre 3 farklı gruba ayrıldı; ışıkla polimerizasyon, iki kez ışıkla polimerizasyon ve kimyasal polimerizasyon. Su emilimi ve suda çözünürlük testi ISO 4049:2009 standardına göre yapıldı. Veriler tek yönlü varyans analizi ile analiz edildi ve Tukey testi anlamlı farklılıkları tespit etmek için kullanıldı (α=0.05). Bulgular: Adeziv rezin simanlar arasında su emilimi ve suda çözünürlük değerleri anlamlı olarak farklıydı (p<0.05). M grubu en yüksek su emilimi değerine sahipken (p<0.05), C grubu en düşük değere sahipti (p<0.05). Suda çözünürlük açısından, en fazla kütle kaybı M grubunda belirlendi. B ve R grupları negatif suda çözünürlük değerleri gösterirken, C ve M grupları pozitif çözünürlük değerleri gösterdi. C ve R grupları için polimerizasyon yöntemleri arasında anlamlı farklılıklar belirlendi (p<0.05). Sonuç: M grubu hariç diğer rezin simanların su emilimi ve suda çözünürlük değerleri ISO standartlarıyla uyumluydu. Polimerizasyon yöntemi R grubunun su emilimini, C grubunun ise su emilimini ve suda çözünürlüğünü etkiledi.Aim: The purpose of the present study was to evaluate the effect of different polymerization types on water sorption and solubility of adhesive resin cements. Material and methods: Two self-etch adhesive resin cements (Duo-Link B, Clearfil Esthetic Cement C) and two selfadhesive resin cements (RelyX U200 Automix R, Maxcem Elite M) were tested in the present study. Twenty-four specimens were prepared for each adhesive resin cement and divided into 3 groups according to the polymerization type used: lightcuring, double light-curing, and self-curing. The water sorption and solubility were determined according to ISO 4049:2009. Data were analyzed with a one-way analysis of variance, and the post-hoc Tukey test (α=0.05). Results: The water sorption and solubility were significantly different among the adhesive resin cements (p<0.05). M group had the highest water sorption values (p<0.05), while C group had the lowest values (p<0.05). Concerning the water solubility, the highest mass loss was noted for M group. B and R groups have exhibited negative solubility; C and M groups positive solubility. Significant differences were noted among the polymerization type in the C and R groups (p<0.05). Conclusion: The water sorption and solubility of resin cements were in accordance with ISO requirement, except M group for water sorption. The polymerization type affected water sorption and solubility of C group, and water sorption of R group

Assessment of tensile strength between base-repair materials and porcelain teeth subjected to different surface treatment

Aim: The purpose of study is to assess the tensile strength between porcelain teeth and two different denture base (polyamide and heat-polymerized acrylic), a repair material (auto-polymerizing acrylic) after different types of surface treatment. Materials and Methods: Total of 63 same form and color mandibular right first molar porcelain denture teeth were used. The first molar porcelain denture teeth were separated into 3 material groups; Group 1: Heat-polymerized (HP), Group 2: Autopolymerizing (AP), and Group 3: Polyamide (PA) (n=21). Then, all material groups were divided into 3 subgroups (n=7) representing different surface treatment method; Control, Airborne abrasion, Er: YAG laser. A universal testing machine was used for determining the tensile bond strength (MPa) of the porcelain denture teeth to surface treated denture base and repair materials. The crosshead speed was set of 0.5 mm/min. Two-way ANOVA and post-hoc Tukey’s HSD was used for statically analyses (?=0.05). The effects of the surface treatment were observed by scanning electron microscopy (SEM). Results: The polyamide (PA) has significantly higher (p0,05). Sonuç: En fazla gerilme kuvveti poliamid kaide materyalinde bulunmuştur. Farklı yüzey uygulamalarının porselen dişlerin gerilme değerlerini etkilemediği görülmüştür

Investigation of the effect of different polishing techniques on the surface roughness of denture base and repair materials

Gundogdu, Mustafa/0000-0003-2527-0392WOS: 000350618500034PubMed: 24853341Statement of problem. the rough surface of denture base materials may cause plaque accumulation and staining. Thus, the effectiveness of polishing techniques should be known. Purpose. the purpose of this study was to compare the effects of chairside polishing kits and conventional laboratory techniques on the surface roughness of denture base and repair materials. Material and methods. Ninety-six specimens, 50 +/- 1 mm in diameter and 0.5 +/- 0.05 thick, were fabricated from heat-polymerized acrylic resin (HP), polyamide resin (PR), and autopolymerizing resin (AP) and submitted to grinding with a tungsten carbide bur. the specimens were divided into 4 groups according to the polishing technique used: control group without polishing, conventional laboratory polishing, polished with Acrylic Polisher HP blue kit, and polished with AcryPoint polishing kit. Surface roughness (R-a) was measured after polishing with a profilometer. Data were analyzed with a 2-way analysis of variance, and the Tukey honestly significant difference (HSD) test was performed to identify significant differences (alpha=.05). Results. the polishing techniques significantly affected the R-a of denture base materials (P.05). Statistically significant differences were found in the R-a between the PR and both the HP and AP (P<.001); PR exhibited the highest R-a values. Conclusions. Conventional laboratory polishing was the most effective polishing technique. A significantly smoother surface than that of the specimens in the control group was produced with chairside silicone polishing kits.Ataturk UniversityAtaturk University [2011/43]This study was supported by Project No. 2011/43 (Ataturk University). Presented at the Inonu University International Dentistry Congress, Malatya, Turkey, April 2012

Farklı yüzey işlemi uygulanan porselen dişler ve kaide-tamir materyalleri arasındaki gerilme kuvvetinin değerlendirilmesi

Aim: The purpose of study is to assess the tensile strength between porcelain teeth and two different denture base (polyamide and heat-polymerized acrylic), a repair material (auto-polymerizing acrylic) after different types of surface treatment. Materials and Methods: Total of 63 same form and color mandibular right first molar porcelain denture teeth were used. The first molar porcelain denture teeth were separated into 3 material groups; Group 1: Heat-polymerized (HP), Group 2: Autopolymerizing (AP), and Group 3: Polyamide (PA) (n=21). Then, all material groups were divided into 3 subgroups (n=7) representing different surface treatment method; Control, Airborne abrasion, Er: YAG laser. A universal testing machine was used for determining the tensile bond strength (MPa) of the porcelain denture teeth to surface treated denture base and repair materials. The crosshead speed was set of 0.5 mm/min. Two-way ANOVA and post-hoc Tukey’s HSD was used for statically analyses (?=0.05). The effects of the surface treatment were observed by scanning electron microscopy (SEM). Results: The polyamide (PA) has significantly higher (p0,05). Sonuç: En fazla gerilme kuvveti poliamid kaide materyalinde bulunmuştur. Farklı yüzey uygulamalarının porselen dişlerin gerilme değerlerini etkilemediği görülmüştür

ZİÇEV'in tarihçesi ve zihinsel engelli bireylerin Türk toplumundaki yeri

Ankara : İhsan Doğramacı Bilkent Üniversitesi İktisadi, İdari ve Sosyal Bilimler Fakültesi, Tarih Bölümü, 2016.This work is a student project of the The Department of History, Faculty of Economics, Administrative and Social Sciences, İhsan Doğramacı Bilkent University.by Emiroğlu, Kudret

Farklı çinko form ve dozlarının mısırın kuru madde verimi üzerine etkisi

Çinko eksikliğinden kaynaklı bitkisel verimde önemli düşüşlerin olduğu bildirilmiştir. Budüşüşlere karşılık alınabilecek en etkin yöntemlerden bir tanesi Zn gübrelemesidir. Bitkinin Znkullanım etkinliğinde, uygulanan gübrenin Zn dozu ve formunun önemli olduğudüşünülmektedir. Bu amaçla, sera koşullarında artan dozlarda [0 (kontrol), 0.2, 1, 5 mg kg-1]ve farklı formlarda (ZnO, ZnSO4.7H2O, Zn-EDTA, ZnCl2) Zn uygulamalarının mısır bitkisininbüyüme, yeşil aksam SPAD değeri, kuru madde verimi, Zn konsantrasyonu ve Zn içeriğiüzerine etkisi belirlenmiştir. Denemede elde edilen bulgulara göre, Zn noksanlığındankaynaklı verim kayıplarının olduğu buna karşılık Zn uygulamasının söz konusu verimkayıplarının önüne geçtiği saptanmıştır. Çinko uygulamasından kaynaklı verim artışoranlarının %9 ile %191 arasında değiştiği, kontrol uygulamasına göre en belirgin artışların 1ve 5 mg kg-1 Zn uygulamalarında olduğu bulunmuştur. Bu artış oranları üzerine uygulanan Znformunun da önemli olabildiği belirlenmiştir. Özellikle en düşük Zn uygulama dozu olan 0.2mg kg-1’da kontrol uygulamasına göre ZnO’den kaynaklı yeşil aksam kuru madde verim artışı%11 elde edilirken bu değer Zn-EDTA, ZnCl2 ve ZnSO4.7H2O için sırasıyla %139, %101 ve%49 olarak saptanmıştır. Çinko uygulamaları, bitkinin yeşil aksam kuru madde verimindeolduğu gibi yeşil aksam Zn konsantrasyonunu da arttırmıştır. Bu artışlarda, Zn uygulamadozunun önemli olduğu buna karşılık uygulanan gübre formunun önemli bir farklılıkyaratmadığı belirlenmiştir. Benzer bulgular bitki başına Zn alınım miktarında da eldeedilmiştir. Sonuçlar genel olarak değerlendirildiğinde en etkin Zn uygulama dozunun 1mg kg-1 olduğu, bunun dışında Zn formları içinde bitkinin büyümesinde ve Zn kullanımetkinliğinde en etkin formun Zn-EDTA olduğu, bunu sırasıyla ZnCl2, ZnSO4.7H2O ve ZnO’inizlediği görülmüştür

Dentin hassasiyet gidericilerin self-adesiv resin simanın yüzey sertliğine ve makaslama bağlantı dayanıklılığına etkisi

Aim: The aim of study is to evaluate the effects of desensitizing agents on the shear bond strengths (SBS) and Vickers surface hardness (HV) of self-adhesive resin cement. Materials and Methods: One-hundred twenty human molars were sectioned parallel to the occlusal plane, polished and randomly divided into 6 groups: Control (CO); Teethmate (TM); Bifluorid (BF); Gluma (GL); Smartprotect (SP); Bisblock (BB). Self-adhesive cement was applied into cylinder mold (3mm×3mm) (N=10). SBS was measured using a Universal testing machine at a 0.5mm/min. Statistical analysis was performed using one-way ANOVA and Tukey’s test (?=0.05). The tooth surface was examined by scanning electron microscopy (SEM). To evaluate HV, self-adhesive cement was applied into cylinder mold (3mm×100µm) (n=10). HV values at the dentin side of cement were evaluated at four times. A load of 200 g was applied for 15 s, and vertical and horizontal indentation diagonals were measured under microscope. All measurements were converted to the Vickers surface hardness (HV) value by using Vickers hardness formula. Data were analyzed by one-way ANOVA and Tukey’s tests (?=0.05). Results: SP group showed the greatest MPa (4.05±1.34 MPa) followed by BB (2.71±1.39 MPa), CO (2.12±0.76 MPa), GL (1.96±1.23 MPa), TM (1.80±0.66 MPa) and BF (1.30±0.57 MPa). BF group showed the lowest HV (11.34±2.24 HV) followed by SP (14.27±3.65 HV), GL (15.58±1.77 HV), BB (16.06±5.73 HV), CO (18.04±3.05 HV), and TM (19.22±2.10 HV). BF desensitizer showed lowest the MPa and HV value. BF desensitizer shows the lowest SBS desensitizer, but this effect is not statically important (p>.05). Conclusions: SP and BB desensitizers have a positive effect on the SBS of self-adhesive cement. For Vickers surface hardness, BF and SP desensitizers showed statically decrease in surface hardness of resin cement (p,05). Sonuçlar: SP ve BB hassasiyet gidericiler self-adesiv resin simanların makaslama bağlanma dayanıklılığına olumlu etkisi bulunmuştur. Yüzey sertliği açısından değerlendirildiğinde BF ve SP hassasiyet gidericiler resin simanın yüzey sertliğinde istatistiksel olarak azalmaya neden olduğu görülmüştür (p<,05)

ADEZİV REZİN SİMANLARIN SU EMİLİMİ VE SUDA ÇÖZÜNÜRLÜĞÜ ÜZERİNE FARKLI POLİMERİZASYON YÖNTEMLERİNİN ETKİSİ

incelenmesidir. Gereç ve yöntem: Mevcut çalışmada 2 farklı self-etch adeziv rezin siman (Duo-Link B, Clearfil Esthetic Cement C) ve 2 farklı self adeziv rezin siman (RelyX U200 Automix R, Maxcem Elite M) test edildi. Her bir adeziv rezin siman için 24 adet örnek hazırlandı ve kullanılan polimerizasyon yöntemine göre 3 farklı gruba ayrıldı; ışıkla polimerizasyon, iki kez ışıkla polimerizasyon ve kimyasal polimerizasyon. Su emilimi ve suda çözünürlük testi ISO 4049:2009 standardına göre yapıldı. Veriler tek yönlü varyans analizi ile analiz edildi ve Tukey testi anlamlı farklılıkları tespit etmek için kullanıldı (α=0.05). Bulgular: Adeziv rezin simanlar arasında su emilimi ve suda çözünürlük değerleri anlamlı olarak farklıydı (p<0.05). M grubu en yüksek su emilimi değerine sahipken (p<0.05), C grubu en düşük değere sahipti (p<0.05). Suda çözünürlük açısından, en fazla kütle kaybı M grubunda belirlendi. B ve R grupları negatif suda çözünürlük değerleri gösterirken, C ve M grupları pozitif çözünürlük değerleri gösterdi. C ve R grupları için polimerizasyon yöntemleri arasında anlamlı farklılıklar belirlendi (p<0.05). Sonuç: M grubu hariç diğer rezin simanların su emilimi ve suda çözünürlük değerleri ISO standartlarıyla uyumluydu. Polimerizasyon yöntemi R grubunun su emilimini, C grubunun ise su emilimini ve suda çözünürlüğünü etkiledi.Aim: The purpose of the present study was to evaluate the effect of different polymerization types on water sorption and solubility of adhesive resin cements. Material and methods: Two self-etch adhesive resin cements (Duo-Link B, Clearfil Esthetic Cement C) and two selfadhesive resin cements (RelyX U200 Automix R, Maxcem Elite M) were tested in the present study. Twenty-four specimens were prepared for each adhesive resin cement and divided into 3 groups according to the polymerization type used: lightcuring, double light-curing, and self-curing. The water sorption and solubility were determined according to ISO 4049:2009. Data were analyzed with a one-way analysis of variance, and the post-hoc Tukey test (α=0.05). Results: The water sorption and solubility were significantly different among the adhesive resin cements (p<0.05). M group had the highest water sorption values (p<0.05), while C group had the lowest values (p<0.05). Concerning the water solubility, the highest mass loss was noted for M group. B and R groups have exhibited negative solubility; C and M groups positive solubility. Significant differences were noted among the polymerization type in the C and R groups (p<0.05). Conclusion: The water sorption and solubility of resin cements were in accordance with ISO requirement, except M group for water sorption. The polymerization type affected water sorption and solubility of C group, and water sorption of R group