Diş Hekimliğinde Uzmanlık Tezleri

Permanent URI for this collection

https://hdl.handle.net/20.500.12645/23110

Browse

Now showing 1 - 20 of 71

Open Access
Farklı Pürüzlendirme Tekniklerinin Braket Çevresinde Mine Demineralizasyonu Oluşturma Etkilerinin Karşılaştırılması / Comparison of Enamel Demineralization Around Orthodontic Brackets With Different Etching Techniques
(2016-03) AYDIN ÖZÇOBAN, Yasemin; Prof. Dr. Serdar ÜŞÜMEZ
Demineralization areas around the brackets observed during orthodontic treatment are of great interest for the orthodontist as demineralization of enamel adjacent to fixed orthodontic appliances can be an esthetic problem for the patient, as well as a problem for the doctor that overshadows the success of the treatment. A new Er:YAG laser handpiece (X-runner) is unique in its ability to digitally control size, shape and depth of irradiated enamel area. This study evaluated the enamel demineralization around brackets bonded following different etching techniques. In this study, total of 100 premolars were divided into four equal groups and received the following treatments: Group 1 Total Etch, acid etching; Group 2 Self Etch, self-etching; Group 3 Lazer M, manual Er:YAG laser etching; Group 4 Lazer X, Er:YAG laser etching with X-Runner handpiece. After placing the brackets, the teeth were cycled through a demineralization-remineralization procedure for 14 days. The solutions were changed daily in order to simulate the saliva flow in the mouth. The teeth were brushed manually with a soft-bristled toothbrush for 30 seconds between each cycle to simulate mechanical wear. The mineral loss on the enamel surface was assessed using Quantitative Light-Induced Fluorescence (QLF). As a result of analysis of QLF four different parameters including ∆F, ∆F max, ∆Q and Area were obtained. Kruskal Wallis test was used for comparisons of parameters between groups. Mann Whitney U test was used in the determination of the group that caused the differences. According to statistical evaluation of the results of QLF analysis there were significant differences among groups for four different parameters (p<0.01). In acid-etch group enamel demineralization around the brackets was significantly higher compared to other experimental groups (p<0.01). Furthermore, demineralization observed in X-runner group was significantly lower compared to manual Er:YAG laser group (p<0.05). There were no significant differences between other groups (p>0.05). Within the limitations of this study, Er:YAG laser etching with X-runner handpiece was considered to be favorable for prevention of enamel demineralization in vitro.
Open Access
Düşük doz lazer tedavisinin ve fotodinamik tedavinin oral mukozit üzerine etkilerinin karşılaştırılması / Comparison of the efficacy of low level laser therapy and photodynamic therapy on the effect of oral mucositis in rats
(Bezmialem Vakıf University, 2017) BAYER ALINCA, Suzan; Prof. Dr. Nergiz YILMAZ
Oral mucositis (OM) induces severe pain and limits fundamental life behaviors such as eating, drinking and talking for patients receiving chemotherapy or radiotherapy. In addition, through opportunistic microorganisms, OM frequently leads to systemic infection which then leads to prolonged hospitalization. Severe lesions often adversely affect curative effects in cancer cases. Therefore, the control of OM is important for oral health quality of life and prognosis. Low level Laser Therapy (LLLT) may be useful to accelerate wound healing. Indocyanine green can improve LLLT affect. In this study, 24 Sprague Dawley rats were divided into 3 groups as control, laser and laser+indocyanine green groups. All groups received 5-Fluorouracil intraperitonally and trauma to the mouth pouch with a needle. After the formation of OM in the mouth, the control group had no treatment; the laser group was administered laser, and the photodynamic therapy had LLLT after indocyanine green application. Then all groups were sacrificed and histologic and basic fibroblast growth factor (bFGF), transforming growth factor (TGF-β) and platelet-derived growth factor (PDGF-BB) were evaluated in all groups. LLLT with indocyanine green application was determined to be statistically significantly more effective than only laser application on bFGF and PDGF-BB groups. However, in respect of TGF-β, no statistically significant difference was observed between the groups. In conclusion, within the limitations of this study, indocyanine green can accelerate LLLT effect. However further studies on this subject are required.
Open Access
Rezin simanların güncel estetik restoratif cadcam materyallerinin rengi üzerine etkisi
(Bezmialem Vakıf University, 2017) GÜRDAL, Işıl; Yrd. Doç. Dr. Ayşe ATAY
The purpose of this study is to investigate the influence of resin cements on the color of recent CAD/CAM materials used for the production of laminate veneers. 7 different kinds of CAD/CAM materials of A2 HT shade were cut into 0,5 and 1 mm thick samples. The samples were cemented with A2 shaded dual-cure, light-cure resin cements and heated composite. The first color measurement were made via spectrophotometer. The specimens were subjected to thermal cycling (5500 cycles) and then second measurements were made. ∆E values were calculated using ∆E formula and the data were uploaded to SPSS software for statistical analysis. According to the results, highest ∆E values were obtained from leucite ceramics while lowest ∆E values were obtained from zirconia reinforced lithium silicate ceramics, resin nanoceramics and hybrid ceramics. Comparing the luting agents, heated composite showed the highest ∆E values while dual-cure resin cements obtained the lowest values. Also it was concluded that restoration material and luting agent significantly affected the ∆E values while thickness showed no significant effect on ∆E.
Open Access
İnternet ortamındaki ortodontik bilgilerin doğruluğunun farklı ölçüm araçlarıyla değerlendirilmesi / Evaluating the accuracy of information about orthodontics avaible on internet using different measurement instruments
(Bezmialem Vakıf University, 2017-10) AK, Rüstem; YRD. DOÇ. DR. BERZA YILMAZ
Besides it is common use for communication purposes internet is also a comprehensive encyclopedic source of information. Health sites on internet are frequently considered as source of information. However, information pollution on the internet can sometimes mislead users. The aim of this thesis is to compare the websites providing information about orthodontic terms in Turkish and in English in matter of quality, accessibility, and usability, to determine the deficient parts of them and to create a guide of content for the sites to be established in the future. In this study, the specific orthodontic terms in Turkish and in English were searched using the Google (Google Inc., Mountain View, CA, ABD) search engine. These terms include; 'orthodontic treatment', 'orthognathic surgery', 'orthodontic appliances', 'orthodontic braces' and 'orthodontic elastics'. Based on the search results 50 sites (25 in Turkish and 25 in English) were selected for each term. The advertisement sites, duplicate websites and public discussion forums were excluded out of the study. Three different measurement tools were used for data evaluation; DISCERN was used to evaluate the quality of orthodontic information, LIDA was used for evaluating the accessibility, the design and reliability of the websites, and AChecker was used to determine the access errors of the websites. The collected data was evaluated between Turkish and in English term groups using Mann-Whitney U test, also Friedman and Wilcoxon Signed Ranks were used for group in evaluation. As a result, statistically significant differences were observed in terms of the quality of orthodontic information in sites both in Turkish and in English, in terms of reliability only in sites in English and in terms of access errors both in Turkish and in English sites. It has been concluded that most of the sites providing information about orthodontics are below the standards determined by the selected measurement tools.
Open Access
Ortodontik bant ve diş arasında oluşan siman boşluklarının ve farklı bant simanlarının çözünürlüklerinin değerlendirilmesi / Evaluation of gaps beneath orthodontic bands and solubility of different band cements
(Bezmialem Vakıf University, 2017-11) ÇALIK KÖSELER, Berra; YRD. DOÇ. DR. BERZA YILMAZ
The purpose of this in vitro study is to evaluate the surface areas of gaps remaining beneath the orthodontic bands cemented with two different methods and different band cements, and compare the solubility and sorption characteristics of these band cements in oral acids and distilled water. In this study, orthodontic bands were cemented to standard sized ceramic tooth samples with conventional glass ionomer cement (Ketac Cem; 3M Espe, Gmbh, Seefeld, Germany), resin modified glass ionomer cement (Multi-Cure; 3M Unitek, Monrovia, California, USA) and polyacid modified glass ionomer cement (Transbond Plus; 3M Unitek, Monrovia, California, USA). After removing of the bands from the tooth surface, the samples were scanned with a three dimensional dental scanner and the surface areas of the gaps between the band and the tooth were measured with a three dimensional design program (SolidWorks 2016). Assessment of sorption and solubility characteristics of the same materials was performed by recording the weight changes of standard sized discs that were immersed in distilled water, lactic acid and propionic acid on the 1st, 7th and 28th days. The largest gaps were recorded in the samples cemented without the occlusal barriers for all three cements (p<0,05). Regardless of the bonding method, the surface areas of the gaps remained between the band and the tooth surface were found similar for conventional glass ionomer (Ketac Cem), resin modified glass ionomer (Multi-Cure) and polyacid modified glass ionomer (Transbond Plus) band cements (p>0,05). The results of the absorption and solubility tests showed that the highest solubility values were recorded for conventional glass ionomer cements and the lowest solubility values for the polyacid modified resin regardless of the storage media, but these results were not statistically significant (p>0,05). The highest sorption values were recorded for the resin modified cement ionomer cement (p <0.05). The highest solubility values were recorded in samples stored in a lactic acid media.
Metadata only
Çeşitli bitkisel özütlerin dental erozyonu önleyici etkilerinin in vitro olarak değerlendirilmesi
(Bezmialem Vakıf University, 2018) SARIALİOĞLU GÜNGÖR, Ayça; Doç. Dr. Nazmiye DÖNMEZ
The aim of this thesis was to evaluate the effect of some plant extracts with the ability to inhibit MMP activity to dentin erosion in vitro.
Open Access
Farklı teflon kaplı estetik tellerin fiziksel ve mikrobiyolojik özelliklerinin incelenmesi / Evaluation of the physical and microbiological properties of teflon coated arch wires
(Bezmialem Vakıf University, 2018) AKYILDIZ, Betül
The lack of esthetic appearance of the orthodontic appliances is one of the greatest concerns for orthodontic patients. The negative perception sometimes causes the patient to give up or postpone the treatment process. A number of esthetic approaches have been introduced such as lingual technique or esthetic brackets to minimize the metallic profile of the fixed devices. The esthetic brackets are used in combination with esthetic arch wires often coated with Teflon hiding the polished metallic surface. However, peeling of the coating material over time results in rough surfaces that are suitable sites for plaque accumulation. Plaque accumulation can lead to periodontal diseases, caries and white spot lesions, and the surface roughness of the esthetic arch wires reduce the performance of sliding mechanics, mechanical strength, color stability, friction, and the success of the treatment mechanics. The aim of this study was to evaluate the surface roughness, microbial plaque retention, and discoloration of round and rectangular cross-sectional Teflon coated arch wire from three different manufacturers in the market. Our study was performed in two stages, in vivo and in vitro conditions. The physical and microbiological characteristics of the Teflon coated 0.016-inch and 0.016 x 0.022-inch arch wire of 3 different manufacturers ((EverWhite (American Orthodontics, Sheboygan, USA), Titanol Cosmetic (Forestadent, Pforzheim, Germany), Proflex (G&H Orthodontics, Franklin, USA)) were examined. Initial (T0) and secondary surface roughness and color change data were collected following 28 days of clinical exposure (T1). Biofilm formation and microbiological properties between the groups were evaluated. As received and retrieved samples from each kind of wire were analyzed. Atomic force microscobe (Brand: NT-MDT Model: Netweaver Solaris) was used to analyze surface roughness. The specimens were prepared by cutting 5 mm from the flat ends of the archwire. Surface roughness values of arch wires are calculated using the software supported by the AFM. In each group, surface topography was evaluated using the average surface roughness (Ra) parameter. The average surface roughness values in all study groups are significantly higher than the initial average (p<0,005). All bacteria were removed from the study samples for investigating the effects of the peeling on bacterial adhesion. Wire samples were incubated in in vitro medium conditions and S. mutans was assesed in terms of colony forming unit (cfu). The amount of S. mutans adhesion of 0.016 x 0.022-inch cross-sectional Proflex wires was significantly lower than the initial average (p = 0.002). The amount of S. mutans adhesion of 0.016-inch cross-sectional Titanol Cosmetic wires was statistically significantly higher than the initial average (p = 0.004). There was no statistically significant difference between the initial mean value of S. mutans bacteria adhesion of 0.016-inch section size Proflex, 0.016 X 0.022-inch section size Titanol Cosmetic, 0.016-inch and 0.016 X 0.022-inch section size Everwhite wires (p>0,005). No statistically significant difference was found between the mean surface roughness values of round wires after 28 days use (p = 0.25). Statistically significant difference was found between S. mutans adhesion measurement values (p = 0,002). It has been determined that the significance is caused by the difference between Proflex and EverWhite; The S. mutans adhesion values in EverWhite wires were found to be high at significantly higher levels than Proflex archwires (p=0,001). There was no statistically significant difference between the mean surface roughness values of rectangular wires and S. mutans adhesion values after 28 days use (p = 0,617 and p = 0,051). It has been found that rectangular sectioned EverWhite archwires showed high bacterial adhesion at statistically significant level from Titanol Cosmetic archwires. Color measurement was performed using VITA Easyshade Compact (VITA Zahnfabrik, Bad Sackingen, Germany, Model DEASYC220) spectrophotometer. No statistically significant difference was found between the color measurement values of the groups. According to the NBS values, a clinically noticeable color change was observed in the Titanol Cosmetic and EverWhite wires, whereas a more remarkable color change was observed in the Proflex wires. In conclusion, we found that the surface roughness values measured with the AFM device were not related to the amount of S. mutans adhesion. Point measurements made with the AFM device were considered to be inadequate alone to make a deduction for all surface topography of the arch wires. All the three different brands of archwires showed clinically noticeable color change.
Open Access
Biyoaktif cam nanopartikülleri ile modifiye edilmiş biodentine materyalinin sitotoksik özelliklerinin değerlendirilmesi/ The cytotoxicity of biodentine modified with nanosized bioactive glass particles
(Bezmialem Vakıf University, 2018) ÖZTÜRK YUCA, Tuğçe; DOÇ. DR. MEHMET BURAK GÜNEŞER
The aim of this study was to evaluate the biocompatibility of Biodentine (Septodont, France) mixed with bioactive glass nanoparticles at 1 wt % and 2 wt %. Bioactive glass nanoparticles was produced by sol-gel technique. The materials was assigned to 3 groups as Biodentine (control group) and Biodentine which modified with bioactive glass nanoparticles %1 wt and %2 wt. After preparation of material discs, groups were divided into 3 subgroups according to setting times (1, 3 and 7 days) (n=20). Before cytotoxicity tests, samples assigned to 2 more subgroups according to incubation time with cells. (24 and 48 hours) (n=10). Following assignation part, cytotoxic properties of the materials were evaluated by MTT method. Data were statistically analyzed by using Kruskall Wallis test and Mann Whitney- U test (p=0,05). No statistical differences were observed between cytotoxicity levels of different material groups (p<0.05). One-day old samples were more cytotoxic than 3-days and 7-days old samples in all test groups (p<0.05). Regardless type of materials, significantly higher cytotoxicity levels were detected at 24 hours incubation time more than 48 hours at 1-day and 3-days old samples (p>0.05). This in vitro study demonstrated that the addition of bioactive glass nanoparticles to Biodentine does not alter its cytotoxicity. Moreover, it is possible to mention that Biodentine and modified Biodentine have initial cytotoxicity.
Open Access
Gümüş eklenmiş çeşitli simanların antibakteriyel etkinliklerinin ve materyal bağlanma dayanımının invitro olarak incelenmesi / Evaluation of the antibacterial effectiveness and the bonding strength of various silveradded cement materials in vitro
(Bezmialem Vakıf University, 2018-04) YILDIRIM, Zeynep Beyza
The aim of this in-vitro work is to examine the physical and antibacterial properties of the orthodontic tapes by adding lyophilized Ag nanoparticles (silver) to the conventional glass ionomer, resin-modified glass ionomer adhesive cement and polyacid modified composite resin materials used for the cementation of orthodontic tapes. In our study, the orthodontic bands were composed of conventional glass ionomer (Ketac Cem), resin modified glass ionomer (Multi-Cure) and polyacid modified composite resin (Transbond Plus) band cements and a total of 138 teeth were formed by the addition of 0.1% lyophilized Ag nanoparticles. The six month aging procedure was applied to the specimens to be subjected to the mechanical test. The desynthesizing of the bands with the 'Instron device (TSTM 02500, Elista, Turkey) was carried out by applying tensile force. The maximum force exerted on the break was measured with the aid of a fixed force gauge attached to the upper part of the instrument and recorded in N (Newton) with the computer connected to the instrument. The values obtained in Newtonian terms were then converted to megapask using the equation Mpa = N / mm², and the statistical analyzes were evaluated as MPa (megapascal). Multi Cure cement without Ag nanoparticle showed the highest tensile strength values; The difference between all groups except the Multi-Cure cement containing Ag nanoparticle was found to be statistically significant (p<0,05). Ketac Cem cement containing Ag nanoparticle; Although higher tensile strength than the Transbond Plus groups and Ag nanoparticle-free the Ketac Cem group without Ag nanoparticles, the only statistically significant difference was seen with the Ag nanoparticles containing Transbond Plus cement (p <0.05). The Ketac Cem feldspar containing Ag nanoparticles is followed by the Transbond Plus groups which do not contain Ag nanoparticles and Ketac Cem and Ag nanoparticles with respectively. Statistically significant difference for both cements was obtained with Multi Cure groups (p <0.05). The lowest tensile strength values were recorded for the Transbond Plus cement containing Ag nanoparticles. At the same time, there was showed a statistically significant difference between the Multi Cure groups and the Ketac Cem groups containing Ag nanoparticles (p<0,05). When the intrinsic tensile strength values were examined, it was seen that the addition of Ag nanoparticle to cement materials did not significantly affect the in-group tensile strength values in the statistically significant level. The cementum residue remaining on the surface of the tooth after the desaturation was visually inspected and scored according to the residual adhesive index (ARI) used by Artun and Bergland. According to the results of the ARI score evaluation, the band cementation break was observed mostly in the Ketac Cem group with and without Ag nanoparticles. It was also seen that the band cement breakage was high in the glass ionomer groups with and without Ag nanoparticles. The highest tensile strengths are found in the adhesive over 50% of the tooth, and the lowest tensile strength is measured in samples that do not have any adhesive on the tooth. Disc diffusion method, liquid medium culture and biofilm formation methods were used for antibacterial evaluation. Discs were produced with the help of Teflon discs with a diameter of 2 mm and a diameter of 9 mm. Antimicrobial properties of all materials were examined by disk diffusion method and Ag nanoparticle was added and examined without addition and no inhibition zone was observed. No difference was observed in CIS as it appeared to reduce the St mutans colonization by RMCIS supplemented with Ag nanoparticles and PMKR added to the liquid medium. Most of the biofilm formation was observed with conventional glass ionomer, Ag nanoparticle-added conventional glass ionomer and component simulator, compared to the absorbance readings measured at 550 nm wavelength in the ELISA reader.
Open Access
Dişeti fenotipini kalınlaştırmak amacıyla ınjectable-platelet-rich-fibrin'in (I-PRF) kullanılması / Using the injectable-platelet-rich-fibrin (I-PRF)for enhancing the gingival phenotype
(Bezmialem Vakıf University, 2018-12) ÖZSAĞIR, Zeliha Betül
A thin gingival biotype is important predisposing factor for gingival recessions. There is still no way to improve the gingival thickness predictably. Platelet rich fibrin (PRF) was developed as a second generation autologous platelet concentrate without the use of anticoagulants or other additives. A liquid injectable-platelet-rich fibrin (I-PRF) was developed by modifying spin centrifugation forces and centrifugation time and utilizing non-glass centrifugation tubes. Wound healing which starts on holes as a result of a lot of microneedling to the tissue ends up with new collagen formation. The holes exist after microneedling increase penetration and efficacy of the applied substances. This randomized controlled clinical trial attempts to evaluate the effect to gingival thickness using I-PRF alone and with microneedle (MN) in individuals with thin gingival thickness. In this split mouth study, 33 systemically healthy patients with thin gingival biotype were randomly treated with MN+I-PRF, and I-PRF. I-PRF was injected on the one side and MN+I-PRF was performed on the other side of the same patient. Plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), gingival thickness (GT), and keratinized tissue width (KTW) were assessed before the treatment and every month for six months after the final injections. After evaluation of the GT between the groups, statistically significant difference was found in the MN+I-PRF group at the sixth month after the final injection. In the intra-group comparisons, a statistically significant increase in GT was observed within both I-PRF [GT increased from 0.43mm±0.14 to 0.62mm±0.11 (p<0.001)] and MN+I-PRF [GT increased from 0,4mm±0,14 to 0,66mm±0,12 (p<0.001)] groups at the sixth month after the final injection. In the intra-group comparisons, a statistically significant increase in KTW was observed within MN+I-PRF group [KTW increased from 2.94mm±1.21 to 2.99mm±0,22 (p<0.001)] at the sixth month after the final injection. In individuals with thin gingival phenotype, I-PRF alone and with MN increased gingival thickness. I-PRF with MN may play a role in increasing the keratinized gingival width.
Metadata only
Güncel diş renkli restoratif dolgu materyallerine farklı uygulama prosedüründeki ev tipi beyazlatma ajanları uygulandıktan sonra fiziksel özelliklerinin in vitro olarak incelenmesi / In vitro investigation of tooth colored restorative materials' physical properties after different application procedures of home bleaching agents
(Bezmialem Vakıf University, 2019) DÖNMEZ KIRAN, Gökçe
The purpose of this in vitro study was to examine the physical properties of tooth colored restorative materials after different application procedures of home bleaching agents procedures in vitro situation. One hundred twenty samples of Ormocer nano-hybrid universal composite resin (Admira Fusion, Voco, Germany); Glass carbomer filler (GCP Glass carbomer, GCP Dental, Netherlands); high viscosity glass ionomer filling (Equia Forte, GC Dental, Japan) and TCD matrix based composite resin (Topaz, Kulzer, Japan) (n:30) were prepared in a metal mold (10x2 mm) according to the manufacturer's instructions. Samples of Admira Fusion and Topaz were polymerized with a LED light curing unit (Valo Cordless, Ultradent, USA) for 20 seconds. 400, 600, 800 and 1000 grit of silicon carbide abrasives were used to pre-flatten the samples under water cooling using the polishing device (Minitech 233, Presi, France), respectively. Then all samples were polished under water cooling with a polishing rubber (Dimanto, Voco, Germany) which contains diamond particles. Resin based surface covering (Equia Forte Coat, GC Dental, Japan) was applied to Equia Forte and polymerized for 20 seconds with a LED light curing unit. After the application of the finishing material (GCP glass, GCP Dental, The Netherlands) on glass carbomer, samples were polymerized with GCP CarboLED light curing unit (GCP Dental, The Netherlands) for 90 seconds. Afterwards, all samples were subjected to thermal aging process (10.000 cycles) with artificial saliva (SD Mechatronic Thermocycler, SD Mechatronic, Germany). For the color measurements a spectrophotometer (Vita Easy Shade Advance 4.0, Vita Zahnfabric, Germany); for the surface roughness a profilometer (MarSurf M 300 C, Mahr Gmbh, Germany) were used. Microhardness measurements were evaluated with a microhardness device (Shimadzu Microhardness Tester HMV-2 Series, Shimadzu, Japan) and the avarage of the measurements were recorded. Then the samples were divided into three groups randomly (n = 10). The first group was a control group and no bleaching procedure was applied on the samples. In the second group 10% carbamide peroxide (CP) agent (Opalescence PF 10%, Ultradent, USA) was applied on the samples for 8 hours per day (14 days) and on the last group 45% CP agent (Opalescence Quick PF 45%, Ultradent, USA) was performed for 30 minutes per day (14 days)s according to the manufacturer's instructions. During the bleaching procedure, all samples were stored in a 37ºC incubator with an artificial saliva solution. After the bleaching procedures were completed (control groups were only kept in the oven), surface roughness and microhardness measurements, color analysis were repeated. Statistical analyses of the data were carried out using SPSS (SPSS Inc., Chicago, Illinois, USA) 15.0 version package programme for Windows. Parametric one-way analysis of variance (ANOVA), Dunnet, Bonferroni tests and Student t test were used for the statistical analyses at a significance level of p <0.05. In this study it was found that, different bleaching procedures did not affect surface microhardness (VMH), total color change (ΔE) and surface roughness values (Ra) of Admira Fusion. VMH and Ra values did not change after 10% CP application to GCP glass carbomer; but ΔE value increased more than the clinically accepted values. It was observed that after 45% CP application all of the parameters were adversely affected and more than the clinically accepted values were investigated. After 10% CP application to Equia Forte; no change were found at VMH and Ra values but ΔE values increased more than the clinically accepted values. After 45% CP application, no change was examined at ΔE and Ra values but increased values were found at VMH values. After 10% CP was applied to Topaz, surface VMH values were decreased but Ra values were not affected. After 45% CP application no statistically significant difference was found between Ra and ΔE values, VHM values showed a decrease. As a conclusion; Old restorations with Admira Fusion may not need to be replaced when both 10% and 45% CP agent containing home bleaching procedures were applied. On the other hand, since the other materials' at least one parameter were negatively affected from bleaching applications, it can be adviced to replace the existing restorations after 10% and 45% CP agent containing home bleaching procedures.
Open Access
ER:Yag lazerin laminate veneer ile diş yüzeyi arasındaki bağlantı dayanımına etkisi The effect of ER:Yag laser on bond strength between the laminate veneer and the tooth surface
(Bezmialem Vakıf University, 2019) ÇETİN, Yeşim; DR. ÖĞR. ÜYESİ IŞIL TURP ; DR. ÖĞR. ÜYESİ ÖZGÜN YUSUF ÖZYILMAZ
The purpose of the current study is to evaluate the effect of Er:YAG laser on the shear bond strengths of porcelain laminate veneer materials with different thickness and compositions. 96 non-carious extracted bovine permanent incisors were used. The teeth were randomly divided into eight groups (n=12). Ceramic discs having thicknesses of 0,5 mm and 1 mm and a diameter of 5 mm were fabricated from feldspathic ceramic and leucite-reinforced ceramic blocks. 96 ceramic discs were prepared for 8 groups consisting of 4 control ((feldspathic ceramic-0.5 mm (FK-0,5), feldspathic ceramic -1mm (FK-1), leucite-reinforced ceramic-0.5 mm (LK-0,5), leucite-reinforced ceramic (LK-1)) and 4 experimental groups ((feldspathic ceramic-0.5 mm (FL-0,5), feldspathic ceramic -1mm (FL-1), leucite-reinforced ceramic-0.5 mm (LL-0,5), leucite-reinforced ceramic (LL-1)). Ceramic disks were bonded to the tooth surfaces following the instructions of the manufacturer. Er:YAG laser was applied to the experimental groups with a power of 4.2 Watt (140 mJ x 30 Hz) for 6 s with scanning method. Shear strength test was performed 1 s after the laser application with a crosshead speed of 1 mm/min at universal testing machine. Failure mode was qualified as adhesive, cohesive or adhesive+cohesive by the aid of a stereomicroscope. The debonded tooth and ceramic surfaces of one sample from each group was analysed with scanning electron microscope (SEM). The data were subjected to statistical analysis by One-way Anova and Tukey HSD post hoc tests. p-value < 0,05 was considered significant. The results revealed statistically significant differences (p≤0.05) between the mean shear bond strength of the control groups and the laser groups. When the different porcelain veneer materials having the same thickness were compared, the difference between groups was not statistically significant (p>0.05). Similarly, there was no statistically significant difference between the groups with different thicknesses of same porcelain veneer materials (p>0.05). The Er:YAG laser application significantly reduces the shear bond strength between the porcelain laminate veneer and the tooth required for debonding. However, ceramic thickness and composition did not have any significant effect on the shear bond strength between the porcelain laminate veneer and the tooth after laser application.
Open Access
Alt yirmi yaş dişlerinin proksimal kontak sıkılığına, ark boyutlarına ve alt keser çapraşıklığına etkisinin değerlendirilmesi / Influence of impacted mandibular third molar teeth onproximal contact tightness, mandibular archperimeters and lower anterior crowding
(Bezmialem Vakıf University, 2019) BİLSEL, Hakan; DR. ÖĞR. ÜYESİ BERZA YILMAZ
The lower incisors crowding, present in the early period of life more or less, is worsening with aging and this situation is considered as a common clinical problem. The etiological factors assumed to affect the late mandibular incisors crowding are stated in the literature as follow; skeletal morphology, growth pattern and late mandibular growth, soft tissue maturation, periodontal forces, anterior component of the occlusal forces, occlusal factors and presence of mandibular third molars. Many clinicians still consider that anterior crowding increases by the mesially directed force resulting from the third molar's eruption. The aim of this study was to investigate the effects of impacted mandibular third molar teeth on the proximal contact tightness on lower posterior segments, mandibular arch perimeters and lower anterior crowding. 60 volunteer dental school students were included in our study in accordance with the selection criteria. The participants were divided into three groups according to presence or absence of their third molar teeth: Bilateral agenesis of lower third molars (Group 1), bilateral impacted lower third molars (Group 2) and bilateral extraction of impacted lower third molars (Group 3). Initial records (T0) included lower study models, cephalometric and panoramic X-rays. Study casts and cephalometric X-rays were taken at 6th month follow up (T2). Interproximal force measurements were carried out at the beginning (T0) and at 6th month follow up (T2) for Groups 1 and 2. Additional interproximal force measurements were performed following the impacted third molar extractions for the Group 3. The data were analyzed by using SPSS (Statistical Package for Social Sciences) for Windows 22.0. There are no significant intergroup differences for interproximal tightness force, arch length, intermolar dimension, inclination and position of incisors parameters at the beginning. However, in Group 3, initial inter-canine dimension and initial irregularity index were significantly less than the other groups. Initial inter-premolar dimension in Group 1 was wider than the others. The interproximal tightness force measurements recorded after extraction and those recorded at the 6th month follow up in Group 3 were found to be significantly lower compared to the initial measurements. There were no significant differences between the initial and 6th month follow up interproximal tightness measurements in Groups 1 and 2. The arch perimeters, irregularity index, inclination and position of incisors and mandibular length were found stable in all groups during the study. There are no significant differences on the position of the lower incisors and on the interproximal tightness forces according to the position of the lower third molars. The inclination of lower incisors is significantly higher on mesioangular and Class C lower third molars. The presence or absence of the lower third molars were found not affecting the initial mandibular arch perimeters, the inclination and position of the lower incisors. However, it was observed that the interproximal tightness values measured from posterior teeth were decreasing immediately after the extraction of the lower third molar teeth, then there was a statistically insignificant increase in these forces during the follow-up period.
Open Access
Dişeti çekilmelerinin tedavisinde titanyum trombositten zengin fibrin (T-PRF) ve bağ dokusu greftinin etkinliklerinin karşılaştırılması / Comparison of the efficacy of the titanium plateletrich fibrin (T-PRF) and connecti̇ve tissue graft in thetreatment of gingival recessions
(Bezmialem Vakıf University, 2019) ÖZTÜRK, Osman
Esthetics, dental hypersensitivity and the prevention of caries and non-carious cervical lesions are considered the main reasons of gingival recession treatment. Subepithelial connective tissue graft (SCTG) is considered the gold standard, although many surgical methods are available for the treatment of gingival recessions. Titanium platelet rich fibrin (T-PRF); it is a platelet concentrate developed in titanium tubes based on the hypothesis that the glass content may be affected by silica during activation of the platelet-rich fibrin (L-PRF) obtained in the glass-covered tubes. The use of titanium causes the fibrin network to become tighter, prolong the resorption time, and a more controlled and prolonged release of growth factors De-epithelized connective tissue graft (DCTG) is obtained by taking the epithelium on the graft extraorally after it is taken with the epithelium. DCTG is a better-performing connective tissue graft thanks to the protection of the more rigid and stable lamina propria located close to the epithelium than SCTG.To date, there is no clinical study that the more stable and organized T-PRF than PRF and the de-epithelial connective tissue graft (DCTG), which is more stable than subepithelial connective tissue graft (SCTG), which is the gold standard in root-surface closure, can be used for predicting the efficacy and predictability of the use of tunnel technique. The aim of this randomized clinical trial was to compare the clinical results of different autogenous graft materials (T-PRF & DBDG) in the treatment of Miller Class I / II gingival recessions. The treatment of 27 patients with Miller Class I / II gingival recession in 80 teeth was completed. Gingival recessions were randomly treated with T-PRF (40 teeth) or DCTG (40 teeth) modified tunnel technique. Clinical measurements were recorded at baseline, 3 months and 6 months after the operation. VAS (Visual Analog Scale), healing index was evaluated and material thickness was recorded. The first gingival recession depth was 3.02 ± 1.15 mm in the T-PRF group and 2.81 ± 0.86 mm in the DCTG group. After 6 months, the mean root closure rate was 78.33% in the T-PRF group and 85.28 in the DBDG group, while the complete root surface mean was 62.5% in the T-PRF group and 70% in the DCTG group. There was no statistically significant difference between the groups for both values. At the end of the treatment, both graft materials were increased the keratinised tissue width and gingival thickness statistically significantly in both groups. Within the limits of this study, it was shown that autogenous T-PRF membrane provide reliable and effective results in the treatment of Miller I / II gingival recession defects. T-PRF can be used as an important alternative to DCTG.
Metadata only
Diode lazer kullanımının E.faecalis biyofilm üzerindeki etkisinin değerlendirilmesi
(2020) BENEZRA, Mira Kebudi
{{abstract}}
Metadata only
Er:YAG lazerin, laminate veneer/diş yüzeyi arasındaki bağlantı dayanımına etkisi
(Bezmialem Vakıf University, 2020) GÜVENER, Nazlı Hilal
{{abstract}}
Open Access
CAD/CAM materyallerine uygulanan farklı polisaj metotlarının streptococcus mutans adezyonuna etkisi Effect of different polishing methods on streptococcus mutans adhesion of CAD/CAM materials
(Bezmialem Vakıf University, 2020) GÜVENER, Nazlı Hilal; DOÇ. DR. ÖZLEM KARA
CEREC Blocs with feldspathic porcelain, IPS e.max CAD with lithium disilicate glass-ceramic, IPS Empress CAD with leucite-reinforced glass- ceramic and CAD/CAM blocks of Vita Suprinity and zirconia reinforced lithium silicate glass ceramic content were used. Enamel sections were used as control group. Ceramic groups (n=20) and natural teeth (n=10) were prepared (5x5x1 mm). The ceramic materials were randomly divided into 2 subgroups (n=10). One group of each material was prepared for glase treatment, the other group was polished with hand tools. Surface roughness for all specimens was measured with a profilometer. The samples were coated with musin containing artificial saliva for 1 hour to form pellicle layer on the surface. After 24 hours of incubation with Streptococcus mutans strain, colonies were counted to determine the retention of microorganisms. SEM images were taken to examine the surface topography. With respect to surface roughness, glazed groups were significantly smoother than enamel section and manual polished groups (p<0.05). The highest mean surface roughness was obtained in the enamel sections. The lowest bacterial density was found in enamel in the groups compared for bacterial adhesion. Glazed CEREC Blocs and manual polished IPS e.max CAD showed the lowest bacterial adhesion after enamel group. Positive correlation without statistically significant between roughness and bacterial adhesion was found (p>0,05). It is concluded that glaze treatment is a more effective method for forming a smooth surface in restorations. The absence of a strong correlation between bacterial adhesion and surface roughness suggests that physicochemical properties are also effective in adhesion.
Metadata only
Farklı Jenerasyon LED Işık Cihazları ile Polimerize Edilen Güncel Dual Cure Bulk Fill Kompozit Materyallerinin Hücre Canlılığı ve Hücre Morfolojisi Üzerine Sitotoksik Etkilerinin İncelenmesi: In Vitro Hücre Kültürü Çalışması/ Investigation of the Cytotoxic Effects on Cell Viability and Cell Morphology of Current Dual Cured Bulk Fill Resin Composites Polymerized With Different Generation Led Light Curing Units: An In Vitro Cell Culture Study
(Bezmialem Vakıf University, 2020-02) KÖYMEN, Safiye Selin; Doc. Dr. Nazmiye DÖNMEZ
The aim of this in vitro cell culture study was to investigate the cytotoxic effects of three different bulk fill composite resin materials in current use and the cytotoxic effects of three different LED light curing units used in the polymerization of these materials on L929 mouse fibroblast cells on vaibility and morphology.
Metadata only
cerrahi destekli hızlı maksiller genişletme sonrası nazal havayolu hacmi ve nazal hava akımındaki değişikliklerin akustik rinometri, rinomanometri ve dental volumetrik tomografi ile karşılaştırmalı olarak değerlendirilmesi
(Bezmialem Vakıf University, 2020-05) ALAGÖZ, Elifhan
Our stduy consists of 13 adult individuals who completed skeletal development ages between 15 and 26, include 3 males and 10 females. In our study, Dental Volumetric Tomograpy image was obtained at 2 different times preoperation and 3 moths after the expansion was completed. Acoustic Rhinometry and Rhinomanometry measurements were made, VAS and NOSE surveys were scored at preoperation and 3 months after the expansion was completed. Nasopharyngeal-oropharyngeal airway volume and areas were calculated by using Romexis 3.8.3. R and Nemotec V2019 software programs. While evaluating the findings of the study, IBM SPSS Statistics 22 program was used for statistical analysis.
Metadata only
Farklı endodontik simanlar ile tamir edilen dış servikal kök rezorpsiyonlu dişlerin vertikal kök kırığı dirençlerinin in vitro değerlendirilmesi/ Ex Vivo Evaluation of Root Fracture Resistance of Teeth With External Cervical Root Resorption Repaired With Different Endodontic Cements
(Bezmialem Vakıf University, 2020-06) MAMMADOVA, Günay; Doc. Dr. Mehmet Burak GÜNEŞER
This study was aimed to assess the fracture resistance of upper human incisor teeth which restored with three different endodontic repair materials after external cervical root resorption was created under ex vivo conditions.

Browse

Browsing Diş Hekimliğinde Uzmanlık Tezleri by Issue Date

Results Per Page

Sort Options