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8. Symmetry Analysis of Initial and Boundary Value Problems for Fractional Differential Equations in Caputo sense

Author

Iskenderoglu, Gulistan and Kaya, Dogan

Subjects
Mathematics - Analysis of PDEs, Mathematical Physics
Abstract

In this work we study Lie symmetry analysis of initial and boundary value problems for partial differential equations (PDE) with Caputo fractional derivative. We give generalized definition and theorem for the symmetry method for PDE with Caputo fractional derivative, according to Bluman's definition and theorem for the symmetry analysis of PDE system. We investigate the symmetry analysis of initial and boundary value problem for fractional diffusion and the third order fractional partial differential equation (FPDE). Also we give some solutions.

Published
2019
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25. Evaluation of Tensile Strength of Surgically Absorbable Suture Materials Used in Oral Surgery after Immersion in Different Beverages: An In Vitro Study.

Author

Aktı, Ahmet and Kaya, Doğan Ilgaz

Subjects
*ORAL surgery, *TENSILE tests, *SURGICAL site, *ARTIFICIAL saliva, *OPERATIVE surgery
Abstract

Suture materials are natural or synthetic biomaterials used to close tissues together. After surgical procedures in the mouth, the surgical site and the sutures are physically affected by many different factors. This study was conducted to evaluate the effects of frequently consumed beverages on the tensile strength of monofilament PGLA (polyglycolide-co-l-lactide) and multi-filament PGCL (polyglycolide-co-caprolactone) absorbable sutures. In particular, PGLA and PGCL absorbable sutures, which are frequently used in oral surgery, were used to evaluate the change in the strength of suture materials. The suture materials were soaked in tea, coffee, and cola drinks five times a day for 5 min each and the rest of the time in artificial saliva. All suture materials were aged via thermal cycling. Tensile strengths were tested at 0, 3, 7, and 14 days. Mixed ANOVA (four replicates: within-group comparison and two factors: between-group comparison) was performed to evaluate the effects of groups and time on the tension levels of the Tekmon and Vicryl suture materials. Analysis of Variance was used for the within- and between-group comparisons, with the Bonferroni corrected t-test for multiple comparisons. For the PGCL suture material, there were significant decreases in tension levels in artificial saliva, tea, coffee, and cola at time T3 compared to T0, T1, and T2, and at T1 and T2 compared to T0. For the PGLA suture material, there were significant decreases in tension levels in artificial saliva, tea, coffee, and cola at time T3 compared to T0, T1, and T2. There was also a significant decrease in tension level at time T2 in cola compared to T0. The present study demonstrates that beverages significantly decrease the strength of suture materials for 14 days after surgery. In particular, cola decreased the resistance of the PGCL suture material more significantly in the first week when compared to other beverages. [ABSTRACT FROM AUTHOR]

Published
2024
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26. Risk Assessment of Nasal Cavity Perforation in the Maxilla: A Virtual Implant Placement Study Using Cone Beam Computed Tomography.

Author

Kaya, Doğan Ilgaz, Şatır, Samed, Öztaş, Beyza, Yıldırım, Hasan, and Aktı, Ahmet

Subjects
*CONE beam computed tomography, *CHI-squared test, *NASAL cavity, *ARTIFICIAL implants, *MAXILLA surgery
Abstract

Implant surgery in individuals with atrophic maxilla presents challenges, particularly concerning nasal cavity complications such as perforations, implant migration, and airway obstruction. While panoramic radiographs offer diagnostic convenience, their two-dimensional nature limits the evaluation of anatomical structures. Cone beam computed tomography (CBCT) provides a three-dimensional assessment, enhancing surgical planning accuracy and potentially reducing complications. With the aim of understanding the measurement differences between panoramic radiographs and CBCT images, this retrospective study examined CBCT images of patients with severely atrophic maxilla taken between September 2021 and December 2023 at the Ahmet Keleşoğlu Faculty of Dentistry. Virtual implants were placed in various tooth regions using OnDemand3D software. The incidence of nasal cavity perforations and vertical bone height differences between panoramic radiographs and CBCT images were evaluated. For this purpose, vertical bone length measurements in panoramic and CBCT images were compared for the virtual implant placement areas. Statistical analyses, including t-tests and ANOVA, were performed to determine significant differences among quantitative measurements, and a chi square test with Bonferroni corrected z-tests were used for possible associations between ratios. CBCT data from 59 patients, totaling 1888 virtual implants, revealed significant differences in implant depths among tooth regions (F = 9.880, p < 0.001). Canine regions showed higher perforation risks, especially with 12 mm and 14 mm implants. Panoramic radiographs often overestimated vertical bone height in canine and first premolar regions compared to CBCT measurements, which could lead to increased perforation risks. Radiographic evaluations using CBCT prior to implant surgery in atrophic maxilla cases are crucial to prevent nasal cavity complications. Panoramic radiographs may inadequately represent three-dimensional anatomy, underscoring the importance of CBCT for accurate implant placement and surgical planning. Further studies should consider varying implant sizes and brands to generalize findings. [ABSTRACT FROM AUTHOR]

Published
2024
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27. Evaluation of the Relationship between Impacted Maxillary Canine Teeth and Root Resorption in Adjacent Teeth: A Cross-Sectional Cone Beam Computed Tomography Study.

Author

Aktı, Ahmet, Dolunay, Uğur, Kaya, Doğan Ilgaz, Gürses, Gökhan, and Yeşil, Doğucan

Subjects
CONE beam computed tomography, ROOT resorption (Teeth), CUSPIDS, RESORPTION (Physiology), INCISORS
Abstract

Background: This study aims to determine the position of impacted maxillary canines on cone beam computed tomography (CBCT) images, to determine the presence of resorption in adjacent teeth, and to investigate the position and type of resorption of impacted canines if resorption is present. Methods: Patients over 14 years of age with maxillary canine teeth who had CBCT images taken for any dental reason were included in the study. Resorption of teeth adjacent to maxillary canines was analyzed according to transversal, vertical, and buccopalatinal positions on the CBCT. The study evaluated 162 maxillary canine teeth on tomography images of 134 patients. Results: Of the affected adjacent teeth, 32.1% of the central incisor, 58.0% of the lateral incisor, and 19.1% of the first premolars showed mild-to-severe resorption. The relationships between transversal position and resorption in the central and lateral incisor, vertical position and resorption in the central incisor and buccopalatinal position and resorption in the first premolars were found to be significant. Maxillary canine teeth can cause mild-to-severe resorption of adjacent teeth, especially lateral incisors. Conclusion: For this reason, we think that a detailed examination with CBCT is essential in the early diagnosis of resorption of adjacent teeth. [ABSTRACT FROM AUTHOR]

Published
2024
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28. Avoiding Sinus Floor Elevation by Placing a Palatally Angled Implant: A Morphological Study Using Cross-Sectional Analysis Determined by CBCT.

Author

Kaya, Doğan Ilgaz, Şatır, Samed, Öztaş, Beyza, and Yıldırım, Hasan

Subjects
*CONE beam computed tomography, *MOLARS, *CROSS-sectional method, *PARANASAL sinuses, *MAXILLARY sinus
Abstract

Backgrounds: Tooth loss in the posterior maxilla often necessitates dental implant placement, but the maxillary sinus anatomy poses challenges, especially during sinus floor elevation. Mesially angled implants are an alternative for total edentulism, but for single tooth deficiencies, palatally angled implants may offer a solution. This study evaluates the prevalence of avoiding sinus floor elevation by placing palatally angled implants in cases with a single missing tooth. Methods: A retrospective study at Ahmet Keleşoğlu Faculty of Dentistry involved 100 participants with a single missing tooth and prior CBCT scans. Virtual implants were placed using OnDemand3D (version 1.0.7462) software. On CBCT sections, implants were angled palatally to avoid sinus or nasal cavity perforation. Statistical analysis was conducted using R and MedCalc (version 4.3.2) software. Results: Of the participants (60% female, average age 50.45), 76 edentulous regions required sinus elevation. The implant placeability rates varied across zones (second molar: 39.3%, first molar: 63.1%, second premolar: 78.5%). Implant placement at a palatal angle was significantly higher in the second premolar and first molar regions. Statistically significant differences were observed in the implant placeability between regions. Conclusions: This study supports the feasibility of avoiding sinus floor elevation through palatally angled implants in specific cases, reducing the associated complications. [ABSTRACT FROM AUTHOR]

Published
2024
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29. Lie symmetry analysis of Caputo time-fractional K(m,n) model equations with variable coefficients.

Author

İSKENDEROĞLU, Gülistan and KAYA, Doğan

Subjects
*CAPUTO fractional derivatives, *CONSERVATION laws (Mathematics), *LIE groups, *EQUATIONS, *SYMMETRY groups, *SYMMETRY
Abstract

In this study, we consider model equations K(m,n) with fractional Caputo time derivatives. By applying the Lie group symmetry method, we determine all symmetries for these equations and present the reduced symmetric equations for the equation K(m,n) with fractional Caputo time derivatives. Furthermore, we obtain the exact solution for K(1,1) with the fractional Caputo time derivative and provide graphs depicting the behavior at different orders of the fractional time derivative. Additionally, by considering the symmetries of the equation, we establish the conservation laws for K(m,m) with the fractional Caputo time derivative. [ABSTRACT FROM AUTHOR]

Published
2024
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36. Application of some nonclassical methods for p-defocusing complex Klein–Gordon equation

Author

Yokuş, Asif, İskenderoğlu, Gülistan, Kaya, Doğan, and Fakülteler, İnsan ve Toplum Bilimleri Fakültesi, Matematik Bölümü

Subjects
Electrical and Electronic Engineering, 1 / G′ method, Klein–Gordon equation, Kudryashov transformation, Partial differential equation, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials
Abstract

This research studies the high-energy Klein–Gordon equation, related to the relativistic Schrödinger wave equation. Solutions are produced using the Kudryashov transform and conventional wave transform. The study’s most significant finding is the examination of the physical and mathematical differences in the traveling wave solutions, derived using two alternative transformations. The graphs of the intensity of the wave function and the conclusions at various velocity levels are also examined. The stability analysis of the moving waves, which coincides with Graham’s diffusion law, of the relationship between wave velocity and density is examined and its relationship with the propagation equation is investigated.

Published
2023

41. The attitude of dentists towards Covid-19 vaccination in Turkey: A survey study

Author

Kaya, Doğan Ilgaz, Demirel, Mehmet Gökberk Kaan, and Kaya, Doğan Ilgaz

Subjects
Dentists, Vaccination, Viral Aşılar, Önleme ve Kontrol, Viral Vaccines, Prevention and Control, Diş Hekimleri, Aşılama, Covid-19
Abstract

Coronavirus disease-2019 (COVID-19) was announced as a global epidemic by the World Health Organization in March 2020. The vaccination program against the epidemic in Turkey started on January 13, 2021. Dentists can easily be exposed to viral spread due to their working conditions. However, the uncertainties in the course of the epidemic and the combination of social trends suggest that hesitation will increase against COVID-19 vaccines. We aimed to determine COVID-19 vaccine acceptance rate in dentists. Material and Methods: A new survey was created for dentists after the COVID-19 vaccination program. For the survey, 11 questions about COVID-19 were determined. The survey was conducted between April 1 and April 15, 2021. Results: Of the 467 individuals participating in the study, 293 (63.0%) were female and 172 (37.0%) were male. Among respondents, 421 (90.1%) subjects were vaccinated, 46 (9.9%) subjects refused to be vaccinated for some reasons. No statistically significant relationship was found between vaccination and age (p=0.138) and gender (p=0.322). It seems that there is no relationship between the vaccination status of the physicians and the place they work. Conslusion: Our study shows that dentists in Turkey participate heavily in vaccination. In order to prevent health services from interrupting and to control the epidemic, campaigns and programs should be made to inform the public. Koronavirüs hastalığı-2019 [coronavirus disease-2019 (COVID-19)], Mart 2020 yılında Dünya Sağlık Örgütü tarafından küresel bir salgın olarak ilan edildi. Türkiye'de salgına karşı aşılama programı 13 Ocak 2021 tarihinde başladı. Diş hekimleri, çalışma koşulları nedeniyle kolaylıkla viral yayılıma maruz kalabilirler. Ancak salgının seyrindeki belirsizlikler ve toplumsal eğilimlerin bir araya gelmesi, COVID-19 aşılarına karşı tereddütlerin artacağını gösteriyor. Bu çalışmada, diş hekimlerinde COVID-19 aşısı kabul oranını belirlemeyi amaçladık. Gereç ve Yöntemler: COVID-19 aşılama programının ardından, diş hekimleri için yeni bir anket oluşturuldu. Anket için COVID-19 ile ilgili 11 soru belirlendi. Anket 1 Nisan-15 Nisan 2021 tarihleri arasında gerçekleştirilmiştir. Bulgular: Çalışmaya katılan 467 kişiden; 293'ü (%63,0) kadın, 172'si (%37,0) erkek idi. Ankete katılanların 421'i (%90,1) aşılanmış, 46'sı (%9,9) bazı nedenlerle aşı olmayı reddetmiştir. Aşı ile yaş (p=0,138) ve cinsiyet (p=0,322) arasında istatistiksel olarak anlamlı bir ilişki bulunamadı. Hekimlerin aşı durumları ile çalıştıkları yer arasında bir ilişki olmadığı görülmektedir. Sonuç: Çalışmamız, Türkiye'de diş hekimlerinin aşı çalışmalarına yoğun olarak katıldığını göstermektedir. Sağlık hizmetlerinin kesintiye uğramaması ve salgının kontrol altına alınması için kamuoyunu bilgilendirmeye yönelik kampanyalar ve programlar yapılmalıdır.

Published
2022

45. YouTube™'da Yer Alan Bruksizm İçin Ağız İçi Cihazlar Hakkındaki Videoların Değerlendirilmesi

Author

Kaya, Doğan Ilgaz, Najafi, Fuad, Selçuk Üniversitesi, Diş Hekimliği Fakültesi, Temel Bilimler Bölümü, Aktı, Ahmet, and Karakaya, Kadir

Subjects
Night Guard, Youtube, Gece Plağı, Bruxism, Intraoral Devices, Ağız İçi Aygıtlar, Bruksizm
Abstract

Background: Stabilization splints can prevent unwanted effects of bruxism. As online healthcare information becomes more popular, YouTube™ has become the first source for users to consult about their health problems. The aim of this study is to evaluate the quality, reliability, and content of the YouTube™ videos about intraoral devices to evaluate whether there is a reliable and useful source for bruxism patients. Methods: In this study, the term “Night Guard” was searched on YouTube™. Sixty videos on the subject were evaluated in terms of content, quality, and reliability. The included videos were analyzed for views, duration, time since video upload, likes/dislikes, number of comments, and source. Each video was classified according to the quality of information content as “useful information”, “misleading information”, “useful user view” and “misleading user view”. The Kruskal-Wallis test, The Mann-Whitney Chi-square test correlation analyses were performed. Results: 18 videos (30%) were uploaded by healthcare professionals, 22 videos (37%) by users, 14 videos (23%) by product suppliers, and 6 videos (10%) by TV / Magazine publishers. In examining the Global Quality Scales (GQS), healthcare professionals have higher scores than others. Reliability scores of the videos uploaded by healthcare professionals are significantly higher than the other groups. (p: 0.003) Also, 17 (%28.3) of the 60 videos are in the misleading video category. Conclusion: YouTube™ can be a platform with the potential for misleading in the use of intraoral devices. Health-related issues should not be tried to be resolved without professional support., Amaç: Stabilizasyon splintleri kas aktivitesini azaltarak bruksizmin istenmeyen etkilerini önleyebilir. Çevrimiçi sağlık hizmetleri bilgileri daha popüler hale geldikçe, YouTube™, kullanıcıların sağlıkla ilgili sorunları hakkında danışmaları için ilk kaynak haline gelmiştir. Bu çalışmanın amacı, bruksizm hastaları için güvenilir ve yararlı bir bilgi kaynağı olup olmadığını değerlendirmek için ağız içi cihazlar hakkında en çok izlenen YouTube™ videolarının kalitesini, güvenilirliğini ve içeriğini değerlendirmektir. Gereç ve Yöntemler: Bu çalışmada, "Gece Plağı" terimi YouTube™ 'da aranmıştır. Konuyla ilgili 60 video içerik, kalite ve güvenilirlik açısından 2 bağımsız araştırmacı tarafından değerlendirilmiştir. Anlaşmazlıklar üçüncü bir araştırmacı tarafından çözülmüştür. Çalışmaya dahil edilen videolar; görüntülemeler, süre, video yüklemesinden bu yana geçen süre, beğenme / beğenmeme, yorum sayısı ve kaynak açısından analiz edildi. Her video, bilgi içeriğinin kalitesine göre “faydalı bilgiler”, “yanıltıcı bilgiler”, “faydalı kullanıcı görüşü” ve “yanıltıcı kullanıcı görüşü” olarak sınıflandırılmıştır. Kruskal-Wallis testi, Mann-Whitney Ki-kare testi korelasyon analizleri yapılmıştır. Bulgular: Sağlık uzmanları tarafından 18 video (% 30), kullanıcılar tarafından 22 video (% 37), ürün tedarikçileri tarafından 14 video (% 23) ve TV / Dergi yayıncıları tarafından 6 video (% 10) yüklendiği görülmüştür. Videoların Global Kalite Ölçekleri (GKÖ) incelendiğinde, sağlık profesyonelleri tarafından yüklenen videoların GKS puanlarının, kullanıcıların, ürün tedarikçilerinin ve TV / Dergi yükleyicilerin puanlarından daha yüksek olduğu anlaşılmaktadır. Videolar yüklendikleri kaynak olarak gruplandırıldığında sağlık mesleği mensupları tarafından yüklenen videoların güvenilirlik puanlarının diğer gruplara göre anlamlı derecede yüksek olduğu anlaşılmaktadır. (p: 0.003) Ayrıca 60 videodan 17'si (% 28.3) yanıltıcı video kategorisindedir. Sonuç: YouTube™, ağız içi cihazların kullanımında yanıltıcı potansiyele sahip bir platform olabilir. Sağlıkla ilgili sorunlar profesyonel destek olmadan çözülmeye çalışılmamalıdır.

Published
2022

49. STRUCTURAL AND SURFACE PROPERTIES OF GLASS POWDER COATED Cr STEELS

Author

ACAR, Ayşe Nur, KAYA, Doğan, EKŞİ, Abdul Kadir, and EKİCİBİL, Ahmet

Subjects
Engineering, Mechanical, Cr steel,glass powder,heat treatment,structural property,surface property, Mühendislik, Makine
Abstract

The most common used glasses are soda-lime-silica glasses, which contain alkaline and alkaline earth oxide materials, such as silicon, sodium, aluminum oxides, etc., and these soda-lime-silica glasses are used in different applications such as windows, bottles, etc. Glass powder is acquired by grinding of waste glass cracks and applied as an additive in structural materials due to its compositions. In this study, the effect of glass powder on the surface and structural properties of Cr steel sheets has been investigated. Cr steels coated with dehydrated glass powder have been annealed at 950 °C temperature in the furnace for various hours and cooled to room temperature in the furnace. The surface and structural properties of these coated steel sheets have been investigated by optical microscopy images, Scanning electron microscopy images, Energy dispersive x-ray spectroscopy data. The crystal structures of these sheet samples have been recorded with x-ray diffraction patterns. As a result, glass powder on the surfaces of Cr steel sheets has not melted homogeneously and surface appearances of these steel sheets have been obtained as waved textures.

Published
2021

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