Yazar "Culhaoglu, Ahmet" seçeneğine göre listele

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    Oral rehabilitation with implant-supported fixed dental prostheses of a patient with cleidocranial dysplasia
    (Mosby-Elsevier, 2018) Atil, Fethi; Culhaoglu, Ahmet; Kocyigit, Ismail Doruk; Adisen, Zahit; Misirlioglu, Melda; Yilmaz, Burak
    This clinical report describes the oral rehabilitation with implant-supported fixed dental prostheses in the maxilla and mandible of a patient with cleidocranial dysplasia. Cone-beam computed tomography and a tilted implant protocol in the mandible helped to establish a conservative approach for bone preservation, prevent surgical complications, enable proper implant positioning to avoid anatomic structures, and support the fixed dental prostheses.
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    Segmentation of Teeth Region via Machine Learning in Panoramic X-Ray Dental Images
    (IEEE, 2020) Guven, Ali; Yetik, Imam Samil; Culhaoglu, Ahmet; Orhan, Kaan; Kilicarslan, Mehmet Kilicarslan
    Segmentation of teeth region from the dental panoramic X-Ray images is an important task in determining various diseases. The main goal of this article is to be able to automatically segment the region of teeth in panoramic x-ray images. First, the center point of the teeth area in the images was determined automatically. Then, a feature set was developed including intensity values of pixels, x-coordinate relative to this center point, y-coordinate relative to this point, and the pixel values obtained by subtraction of maximum and minimum values in 3x3 window. CatBoost algorithm was used for machine learning. When creating the machine learning model, k-fold cross validation of training data set and grid search optimization of hyper parameters, were applied to avoid over fitting of data set. The results were analyzed using the learning curve, F1, accuracy, recall, and precision scores.
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    Surface roughness and adaptation of different materials to secure implant attachment housings
    (Mosby-Elsevier, 2017) Ozkir, Serhat Emre; Yilmaz, Burak; Kurkcuoglu, Isin; Culhaoglu, Ahmet; Unal, Server Mutluay
    Statement of problem. Various materials are available to secure implant attachment housings in overdentures. Surface roughness and the adaptation of these materials to the denture base and the housings may increase the microcracks and bacterial adhesion at the interfaces in the long term. The surface characteristics of the interface between the denture base orientation material and the attachment housing have not been extensively studied. Purpose. The purpose of this in vitro study was to evaluate the surface roughness and the adaptation of 5 different housing orientation materials to the housings and the denture base. Material and methods. Fifty-five poly(methyl methacrylate) (PMMA) specimens (15 mm in diameter and 4 mm in height) were prepared with a clearance inside to allow the insertion of over denture housings. Five different materials were used for housing orientation (Quick Up, Ufi Gel Hard, Tokuyama Rebase II Fast, Meliodent, and Paladent). The specimens were thermocycled 5000 times between 5 degrees C and 55 degrees C. The surface roughness (Ra values) of the specimens was measured with a noncontact profilometer. Scanning electron images were made in order to inspect the PMMA-orientation material-housing interfaces. The Kruskal-Wallis test was used to investigate the differences between the surface roughness values of the orientation materials, and the Iman-Conover test was used for pairwise comparisons (alpha=.05). Results. The surface roughness values significantly differed between Quick up and Ufi Gel orientation materials only, and Quick up had smaller surface roughness values than Ufi Gel (P=.009). Microcracks were observed among the groups only at the junction of the orientation material and the housing after thermocycling. Conclusions. Ufi Gel Hard showed the roughest surfaces around the overdenture attachment housings. The adaptation between the orientation material and the housing may deteriorate, and increased surface roughness and microcrack formation may be seen around the housings.