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Öğe Effect of surface wetting resin on the color stability and microhardness of esthetic composites(Univ Costa Rica, Fac Odontologia, 2021) Cangül, Suzan; Erpaçal, Begüm; Adıgüzel, Özkan; Ünal, Mehmet; Günay, AyşeObjective: The aim of this study was to evaluate and compare the effects of the superficial application of two different modeling resins on the surface microhardness and discoloration of composite resins. Material and Methods: The present study used two different composites and modeling resins. The composites were placed in plastic molds. Subsequently, the modeling resins were applied on the surface of the two composite groups. The microhardness and color pertaining to all the groups were evaluated. The current study used the One-Way ANOVA and Kruskal Wallis tests, in order to perform the statistical evaluation (p<0.05). Results: The present study compared the microhardness pertaining to the groups and the highest microhardness values were observed in the Estelite Asteria group (none), whereas the lowest values were observed in the GC Essentia group (Ultradent). Moreover, the current study evaluated the color stability and the greatest discoloration was observed in the control group of the GC Essentia group, whereas the least discoloration was observed in the Estelite Asteria group that included the samples prepared using Ultradent Wetting Resin. Conclusions: The results of the present study demonstrated that the use of modeling resins, which facilitate the placement of composite resins, reduced the microhardness and discoloration of composite resins. The aforementioned effect can be attributed to the variations in the structure of the filling. However, further studies are warranted to support and verify the results of the current study.Öğe The evaluation of effectiveness of adhesive systems on dental amalgam restorations(Uluslararası Diş Araştırmaları Birliği, 2021) Ünal, Mehmet; Atakul, FatmaAim: The purpose of this study was to evaluate the effectiveness of different adhesive systems in amalgam restorations and their effects on microleakage. Methodology: In this study, 105 caries-free extracted human permanent molar teeth were used. Teeth were randomly assigned to five groups (n=21), and class I cavities were created on the surface of each tooth. The first was a control group to which no adhesive system was applied. Amalgam Liner (VOCO GmbH, Cuxhaven Germany) was applied to Group II, Clearfil SE-Bond (Kuraray Europe GmbH, Frankfurt Germany) was applied to Group III, Panavia F 2.0 (Kuraray Europe GmbH, Frankfurt Germany) was applied to Group IV, Amalgambond Plus (Parkell Inc.Edgewood, NY USA) was applied to Group V, and then amalgam (Tytin, Kerr, California USA) restorations were placed. After the polishing process, samples were subjected to thermocycling 1,000 times. Teeth were sectioned buccopalatinally/lingually, and microleakage scores of the occlusal walls were evaluated under a stereomicroscope at 15X magnification by a standardized scale ranging from 0 to 4. One tooth was selected randomly from each group for SEM (Scanning Electron Microscope), and SEM LEO EVO 40 (LEO Ltd., Cambridge UK) photographs of amalgam-tooth hard tissue interfaces were also taken at different magnifications. The results of the microleakage tests were statistically analyzed by both the Kruskal-Wallis Test and the Mann Whitney U Test. Results: In terms of microleakage among groups, the differences that were determined were significant (p<0.05). Microleakage within the control group was determined to be the highest, and statistically important differences were observed between the other groups. Group V (Amalgambond Plus) was determined to have the lowest microleakage scores. Conclusion: In prepared class I cavities, amalgam adhesive systems are effective in preventing occlusal microleakage but do not completely blocked it.Öğe Evaluation of shear bond strength of amalgam restorations repaired with composite resin by different surface treatments(Uluslararası Diş Araştırmaları Birliği, 2019) Cangül, Suzan; Adıgüzel, Özkan; Erpaçal, Begüm; Ünal, Mehmet; Acartürk, Musa; Satıcı, ÖmerAim: Repairing amalgam restorations with composite resins is a clinicalpractice with many advantages. An effective adhesion is achievedbetween amalgam and composite by applied different surface treatmenton amalgam surface. In this study, the effect of adhesive systems appliedon amalgam surface on composite-amalgam connection was investigated.Methodology: Standard cavities were opened in 70 acrylic molds thathad completed their polymerization and amalgams were placed in thesecavities. Seven groups were randomly assigned to different surfacetreatments on amalgam. In group 1 only roughening with diamond bur, ingroup 2 acid etch, in group 3 acid application after roughening withdiamond bur, in group 4 roughening with diamond bur and silane, in group5 acid etch and silane, in group 6 roughening with diamond bur and AlloyPrimer and finally 7. acid etch and Alloy Primer was applied in thesamples. After the application of clearfil universal bond to all groups,composite resins were placed and polymerized. Shear bond strengthswere tested with a Universal testing machine. Obtained data wereevaluated by one way ANOVA and Tukey B tests.Results: In the statistical evaluation of the groups, the highest shearbond strength between amalgam-composite was seen in the 3rd groupwhere both roughening with diamond bur and acid were applied together,and the lowest shear bond strength was seen in the first group with onlyroughening with diamond bur. The differences between the groups werestatistically significant (p<0.05).Conclusions: The roughening of the amalgam surface affects the shearbond strength between amalgam and composite resin. These resultsobtained in vitro conditions should be supported with clinical studies.Öğe Koruyucu restoratif tedavilerde kullanılan farklı materyallerin etkinliklerinin araştırması(2015) Ünal, MehmetAmaç: Bu araştırmanın amacı; koruyucu restoratif tedavilerde uygulanan amalgam restorasyonların adeziv sistemlerle beraber etkinliklerini mikrosızıntı açısından in-vitro koşullarda değerlendirmektir. Gereç ve yöntem: Araştırmada değişik nedenlerden dolayı (cerrahi, ortodontik) çekilmiş 100 adet çürüksüz molar diş kullanıldı. Çekim sonrasında dişler üzerindeki yumuşak dokular ve artıklar bir kretuar, pomza ve fırça yardımıyla uzaklaştırıldı. Tüm dişlerin okluzal yüzeylerine su soğutması altında silindirik elmas frezle standart sınıf-I kaviteler hazırlandı. Her kavite mezio-distal genişliği 4 mm, bukkal-lingual genişliği 2 mm ve derinliği 2 mm olarak hazırlandı. Ardından her bir grupta 20 adet olacak şekilde dişler rastgele beş gruba ayrıldı. 1. Grup kontrol grubu olarak hiçbir adeziv sistem uygulanmadan amalgam retorasyonu (Tytin, Kerr, California, USA) yapıldı. 2. Gruba Amalgam Liner (VOCO GmbH, Cuxhaven, Germany), 3. Gruba Clearfil SE-Bond (Kuraray Europe GmbH, Frankfurt, Germany), 4. Gruba Panavia F 2.0 (Kuraray Europe GmbH, Frankfurt, Germany), 5. Gruba Amalgambond Plus (Parkell Inc., Edgewood, NY, USA) üretici firmalarının önerileri doğrultusunda uygulanarak amalgam restorasyonları yapıldı. Kavite preperasyonları yapılan dişler 24 saat 37 oC’de etüvde (Nüve Incubator EN 500, Ankara, Türkiye) bekletildi. 24 saatlik sertleşmesi tamamlanan amalgamların cila işlemleri polisaj lastikleri ile su soğutması altında yapıldı. Cila işlemi biten örnekler termal siklus işlemine tabi tutuldu. Termal siklus işlemi su banyosunda (Memmert GmbH, Schwabach, Germany) 15 sn bekleme süresi olmak üzere 5±2 oC ve 55±2 oC’ler arasında 1.000 kez uygulandı. Dişlere kavite sınırlarının 1mm dışından geçecek şekilde 2 kat tırnak cilası sürülüp sertleşmesi beklendi. Dişler 24 saat 37 oC’deki %0,5’lik bazik fuksin solüsyonunda bekletildikten sonra musluk suyu altında yıkanarak fazla boyanın uzaklaşması sağlandı. Elde edilen kesit yüzeylerindeki okluzal sızıntı değerleri binoküler stereooptik mikroskopta 15X büyütmede, dişler, standart bir skala ile 0-4 arasında skorlandı. Elde edilen sonuçlar istatistiksel olarak Kruskal-Wallis ve Mann Whitney-U testleri ile değerlendirildi. Ayrıca, her gruptan rastgele birer örnek seçildi ve amalgam-diş sert dokusu ara yüzeyi LEO EVO 40 (LEO Ltd., Cambridge, UK) SEM cihazı altında farklı büyütmelerde incelenip fotoğraflandı.
