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Öğe Clindamycin phosphate and bone morphogenetic protein-7 loaded combined nanoparticle-graft and nanoparticle-film formulations for alveolar bone regeneration – An in vitro and in vivo evaluation(Elsevier B.V., 2023) Ilhan, Miray; Kilicarslan, Muge; Alcigir, Mehmet Eray; Bagis, Nilsun; Ekim, Okan; Orhan, KaanCommonly utilized techniques for healing alveolar bone destruction such as the use of growth factors, suffering from short half-life, application difficulties, and the ability to achieve bioactivity only in the presence of high doses of growth factor. The sustained release of growth factors through a scaffold-based delivery system offers a promising and innovative tool in dentistry. Furthermore, it is suggested to guide the host response by using antimicrobials together with growth factors to prevent recovery and achieve ideal regeneration. Herein, the aim was to prepare and an in vitro - in vivo evaluation of bone morphogenetic protein 7 (BMP-7) and clindamycin phosphate (CDP) loaded polymeric nanoparticles, and their loading into the alginate-chitosan polyelectrolyte complex film or alloplastic graft to accelerate hard tissue regeneration. PLGA nanoparticles containing CDP and BMP-7, separately or together, were prepared using the double emulsion solvent evaporation technique. Through in vitro assays, it was revealed that spherical particles were homogeneously distributed in the combination formulations, and sustained release could be achieved for >12 weeks with all formulations. Also, results from the micro-CT and histopathological analyses indicated that CDP and BMP-7 loaded nanoparticle-film formulations were more effective in treatment than the nanoparticle loaded grafts. © 2023 Elsevier B.V.Öğe Clindamycin phosphate and bone morphogenetic protein-7 loaded combined nanoparticle-graft and nanoparticle-film formulations for alveolar bone regeneration-An in vitro and in vivo evaluation(Elsevier, 2023) Ilhan, Miray; Kilicarslan, Muge; Alcigir, Mehmet Eray; Bagis, Nilsun; Ekim, Okan; Orhan, KaanCommonly utilized techniques for healing alveolar bone destruction such as the use of growth factors, suffering from short half-life, application difficulties, and the ability to achieve bioactivity only in the presence of high doses of growth factor. The sustained release of growth factors through a scaffold-based delivery system offers a promising and innovative tool in dentistry. Furthermore, it is suggested to guide the host response by using antimicrobials together with growth factors to prevent recovery and achieve ideal regeneration. Herein, the aim was to prepare and an in vitro -in vivo evaluation of bone morphogenetic protein 7 (BMP-7) and clindamycin phosphate (CDP) loaded polymeric nanoparticles, and their loading into the alginate-chitosan polyelectrolyte complex film or alloplastic graft to accelerate hard tissue regeneration. PLGA nanoparticles containing CDP and BMP-7, separately or together, were prepared using the double emulsion solvent evaporation technique. Through in vitro assays, it was revealed that spherical particles were homogeneously distributed in the combination formulations, and sustained release could be achieved for >12 weeks with all formulations. Also, results from the micro-CT and histopathological analyses indicated that CDP and BMP-7 loaded nanoparticle-film formulations were more effective in treatment than the nanoparticle loaded grafts.Öğe Effect of Systemic Oxytocin Administration on New Bone Formation and Distraction Rate in Rabbit Mandible(W B SAUNDERS CO-ELSEVIER INC, 2020) Altay, Berkan; Dede, Eda Ciftci; Ozgul, Ozkan; Atil, Fethi; Kocyigit, Ismail Doruk; Orhan, Kaan; Tekin, UmutPurpose: The main disadvantage of distraction osteogenesis is the prolonged treatment protocol. Recently, oxytocin (OT) has been found to have anabolic effects on bone metabolism. In this experimental study, the effects of OT on the mandibular distraction gap in rabbits at 2 different distraction rates were evaluated. Materials and Methods: This experimental study was conducted on 28 male New Zealand white rabbits. The animals were divided into 3 experimental groups and 1 control group. Group A (control group, n = 7) consisted of animals with distraction at a rate of 1 mm/day, and group B (n = 7) consisted of animals with a distraction rate of 2 mm/day; groups A and B received postoperative saline solution injection. Group C (n = 7) consisted of animals with distraction at a rate of 1 mm/day, and group D (n = 7) consisted of animals with a distraction rate of 2 mm/day; postoperative OT injection was performed in groups C and D. Results: Both histomorphologic and micro-computed tomography evaluations showed increased bone healing in the OT-treated groups. Conclusions: On the basis of the evaluation of both the histomorphometric and micro-computed tomographic data, systemic OT administration was found to increase new bone formation and bone healing with distraction osteogenesis. (C) 2020 American Association of Oral and Maxillofacial SurgeonsÖğe Evaluation of Perimandibular Neurovascularization With Accessory Mental Foramina Using Cone-Beam Computed Tomography in Children(Lippincott Williams & Wilkins, 2013) Orhan, Ayse Isil; Orhan, Kaan; Aksoy, Secil; Ozgul, Ozka; Horasan, Sinan; Arslan, Ahmet; Kocyigit, DorukObjectives: The purpose of this study was to clarify the perimandibular neurovascularization with mandibular accessory mental foramina in a children population using cone-beam computed tomography (CBCT) to avoid complications during anesthetic and surgical procedures. Methods: This retrospective study evaluated cone-beam CT images for bifid mandibular canals in the mandibles of 63 children (35 girls, 28 boys; age range, 7-16 years; mean age, 12.3 years). Both right and left sides were examined from CT images (n = 126), including axial, sagittal, cross-sectional, and panoramic views as well as reconstructed three-dimensional images, as necessary. The course, length, and superior and inferior angles between canals were classified and measured. Results: Bifid mandibular canals were observed in 34 (27%) of the 126 sides examined. The most frequently encountered type of bifid canal was the retromolar canal (11.1%), followed by the forward (7.14%), buccolingual (6.35%), and dental canal (2.4%). Mean lengths of bifid canals were 10.2 mm on the right side and 10.6 mm on the left side. Mean superior angles were 131 degrees on the right side and 147 degrees on the left side, whereas mean inferior angles were 47 degrees on the right side and 34 degrees on the left side. No statistically significant differences were found in the lengths or angles between the right and left sides or between boys and girls (P < 0.05). The most common position for the mental foramen was between the first and second premolars, and an accessory mental foramen was observed in 4 children (6.34%). Conclusions: This study utilized CBCT images to identify bifid mandibular canals and accessory mental foramina in children. Cone-beam CT was found to be a useful technique for detecting secondary canals. However, despite the fact that CBCT uses less ionizing radiation than other types of three-dimensional imaging, unless the diagnostic information provided through CBCT improves treatment results, CBCT should not be recommended for use in children or adolescents.Öğe Evaluation of Preoperative Model Surgery and the Use of a Maxillary Sinus Surgical Template in Sinus Floor Augmentation Surgery(Lippincott Williams & Wilkins, 2013) Kocyigit, Ismail Doruk; Coskunses, Fatih Mehmet; Ozgul, Ozkan; Tuz, Hakan Hifzi; Kartal, Yasemin; Polat, Muhlis; Orhan, KaanMaxillary sinus augmentation is an accepted technique for dental implant placement in presence of insufficient maxillary bone. There are various techniques in the literature, either by crestal or lateral approach in maxillary sinus augmentation that have high percentage of success, while all have complications. Schneiderian membrane perforation is the most common complication encountered during surgery. The aim of this study was to evaluate the benefits of preoperative model surgery and the ease of use of a maxillary sinus surgical template (MSST) during maxillary sinus augmentation surgery with a lateral approach. Ten patients included in the study needed rehabilitation of a partially or totally edentulous maxilla with an implant-supported fixed prosthesis and requiring sinus augmentation. A questionnaire was asked to performing surgeons, and study results showed the use of an MSST was found to be effective in terms of adaptation (62.5%), window preparation (87.5%), ease of elevation (95.9%), ease of grafting (95.9%), reduction of perforation risk (91.7%), and achieving immobility during the procedure (62.5%); however, the use of an MSST was also found to prolong the surgical procedure (100%) and restrict the view of the surgical area (79.2%). Maxillary sinus augmentation appears to be a useful tool for locating an appropriate entrance to the sinus cavity, allowing for safe elevation of the sinus membrane and effectively grafting the sinus floor.Öğe Influence of Cone-Beam Computed Tomography Voxel Sizes in the Detection of Chemically Induced External Root Resorptions(Int Scientific Information, Inc, 2022) Kolsuz, Mehmet Eray; Eren, Hakan; Celikten, Berkan; Evli, Perihan Dalgali; Kocasarac, Husniye Demirturk; Orhan, KaanBackground: External root resorption usually does not present a clinical sign or symptom, and, therefore, diagnosis is mainly based on radiographic examination. Many studies confirmed the advantage and accuracy of cone-beam computed tomography (CBCT) in evaluating root resorptions. We aimed to evaluate the diagnostic accuracy of CBCT images of chemically induced external root resorptions on extracted human teeth taken in different vox el sizes. Material/Methods: In this in vitro study, 36 maxillary and 36 mandibular human incisor teeth, extracted owing to periodontal disease, were used. External resorption cavities were created on the buccal and proximal surfaces by using 10% hydrochloric acid with different application periods of 10, 30, and 60 min. Resorption cavities in different depths were induced to simulate different levels of external resorption. CBCT images were taken with Planmeca Promax 3D Max CBCT (Planmeca, Helsinki, Finland) in 4 different voxel sizes: 400, 200, 150, and 100 mu m. Results: There was no statistically significant difference between interobserver and intraobserver reliability. Higher observer agreement was obtained for 100-mu m and 150-mu m voxel sizes. For detection of external root resorption defects, interobserver agreement was highest for the 100-mu m voxel size and when defects were located on the proximal side of the samples. The highest k values were obtained for samples kept in hydrochloric acid for 60 min. Conclusions: Chemically induced resorption cavities should be used for experimental studies to better imitate clinical conditions. CBCT requirement is still ambiguous for detection of external resorptions, and more experimental and clinical studies are needed.Öğe Quantitative assessment of image artifacts from zygoma implants on CBCT scans using different exposure parameters(Sage Publications Ltd, 2023) Orhan, Kaan; Kocyigit, Doruk; Firincioglulari, Mujgan; Adisen, Mehmet Zahit; Kocyigit, SedaThis study was aimed at quantifying artifacts from zygoma implants in cone-beam computed tomography (CBCT) images using different exposure parameters. Two cadaver heads, one with two zygoma implants on each side and the other for control, were scanned using 18 different exposure parameters. Quantitative analysis was performed to evaluate the hypodense and hyperdense artifact percentages calculated as the percentage of the area. Hyperdense artifacts and hypodense artifacts were detected, followed by the calculation of the hyperdense and hypodense artifact percentages in the image. In the qualitative analysis of the artifacts, the scores used were as follows: absence (0), moderate presence (1), or high presence (2) for hypodense halos, thin hypodense lines, and hyperdense lines. Artifact analysis was performed qualitatively and quantitatively using the post-hoc Tukey and Two-way ANOVA tests. As a result, in the qualitative analyses, zygoma implants showed a significant difference compared to the control group with regard to hyperdense and hypodense artifacts (p < 0.05). There was a significant difference between the means according to the FOV size arithmetic averages (p < 0.05). In terms of voxel size, the difference was found to be significant, where 400 microns showed the highest hypodense artifact while 200 microns showed the lowest hypodense artifact. In conclusion, hypodense and hyperdense artifacts were significantly higher in cadavers with zygoma implants than in controls. As FOV and voxel size increase, more hypodense artifacts are produced by zygoma implants so smaller FOV and voxel sizes should be used to prevent poor image quality of adjacent teeth.Öğe 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 KilicarslanSegmentation 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.Öğe Semi-Supervised Method for Determining the Maxillary and Mandibular Boundaries on Panoramic Radiographs(Ieee, 2018) Ulku, Berkay Kagan; Yetik, Imam Samil; Culhaoglu, Ahmet Kursad; Orhan, Kaan; Kilicarslan, Mehmet AliX-ray imaging plays an important role in the detection and diagnosis of dental disorders that can not be detected with the eye. Examination, evaluation and accurate diagnosis of panoramic radiography images used in anomaly detection is a process requiring serious experience and expertise. In order to simplify this process and to increase accuracy, some studies have been carried out on both the imaging techniques and the development of the computer aided diagnosis systems by transferring these images to the digital medium. One of these studies is segmentation of various structures in dental X-ray images. In this study, instead of using random masks as initial inputs, we developed a special mask identification method for each image and gave the mask which is the output of this method as initial input to the segmentation algorithm to obtain more suitable elliptical forms closer to the actual(ground truth) results and to the maxillary and mandibular structures.Öğe Using artificial intelligence models to evaluate envisaged points initially: A pilot study(Sage Publications Ltd, 2023) Amasya, Hakan; Aydogan, Turgay; Cesur, Emre; Kemaloglu Alagoz, Nazan; Ugurlu, Mehmet; Bayrakdar, Ibrahim Sevki; Orhan, KaanThe morphology of the finger bones in hand-wrist radiographs (HWRs) can be considered as a radiological skeletal maturity indicator, along with the other indicators. This study aims to validate the anatomical landmarks envisaged to be used for classification of the morphology of the phalanges, by developing classical neural network (NN) classifiers based on a sub-dataset of 136 HWRs. A web-based tool was developed and 22 anatomical landmarks were labeled on four region of interests (proximal (PP3), medial (MP3), distal (DP3) phalanges of the third and medial phalanx (MP5) of the fifth finger) and the epiphysis-diaphysis relationships were saved as narrow,'' equal,'' capping'' or fusion'' by three observers. In each region, 18 ratios and 15 angles were extracted using anatomical points. The data set is analyzed by developing two NN classifiers, without (NN-1) and with (NN-2) the 5-fold cross-validation. The performance of the models was evaluated with percentage of agreement, Cohen's (c kappa) and Weighted (w kappa) Kappa coefficients, precision, recall, F1-score and accuracy (statistically significance: p < 0.05). Method error was found to be in the range of ck: 0.7-1. Overall classification performance of the models was changed between 82.14% and 89.29%. On average, performance of the NN-1 and NN-2 models were found to be 85.71% and 85.52%, respectively. The ck and wk of the NN-1 model were changed between 20.08 (p > 0.05) and 0.91 among regions. The average performance was found to be promising except the regions without adequate samples and the anatomical points are validated to be used in the future studies, initially.
