Yazar "Gul, Mehmet" seçeneğine göre listele
Listeleniyor 1 - 9 / 9
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Biomechanical Evaluation of Implant Osseointegration After Guided Bone Regeneration With Different Bone Grafts(Lippincott Williams & Wilkins, 2021) Gunes, Nedim; Gul, Mehmet; Dundar, Serkan; Tekin, Samet; Bozoglan, Alihan; Ozcan, Erhan Cahit; Karasu, NecmettinThe aim of this study was to compare the biomechanical osseointegration of titanium implants after guided bone regeneration (GBR) with a hydroxyapatite graft, deproteinized bovine bone graft, human-derived allograft, and calcium sulfate bone graft. Thirty-two female Sprague Dawley rats were divided into four groups, each containing eight (n = 8) rats: hydroxyapatide (HA), deproteinized bovine bone graft (DPBB), allograft (ALG), and calcium sulfate. Bone defects were created in the tibia of the rats, which were grafted with HA, DPBB, ALG, or CP bone grafts for the purpose of GBR. Ninety days after surgery, machine-surfaced titanium implants were inserted into the area where GBR had been undertaken. After 90 days of the surgical insertion of the implants, the rats were sacrificed, the implants with surrounding bone tissue were removed, and biomechanical osseointegration (N/cm) analysis was performed. No statistically significant differences were found among the groups in osseointegration (N/cm) three months after the GBR procedures (P > 0.05). According to the biomechanical results, none of the grafts used in this study was distinctly superior to any of the others.Öğe Diagnosis of Leptomeningeal Metastases Disease in MRI Images by Using Image Enhancement Methods(Zarka Private Univ, 2017) Gul, Mehmet; Karal, Sadik; Isikdogan, Abdurrahman; Yarar, YusufLeptomeningeal Metastases (LM) disease is the advanced stages of some complicated cancers. It Contaminates in the Cerebrospinal Fluid (CSF). Tumors might be in macroscopic or microscopic sizes. The medical operation is more risky than other cancers. Consequently, diagnosis of leptomeningeal metastases is important. Different methods are used to diagnose LM disease such as CSF examination and imaging systems Magnetic Resonance Imaging (MRI) or Computer Tomography (CT) examination. CSF examination result is more accurate compared to CT or MRI imaging systems. However imaging systems results are taken more early than CSF examination. Some details in MRI images are hidden and if the proper image enhancement method is used, the details will be revealed. Diagnosis of LM disease can be earlier with accurate results at that time. In this study, some image enhancement methods were used. The probability of result of Logarithmic Transformation (LT) method and Power-Law Transformation (PLT) method were almost the same and result was p=0.000 (p<0.001), and statistically high result was obtained. The probability of Contrast Stretching (CS) method was p=0.031 (p<0.05), and this result was statistically significant. The other four methods results were insignificant. These methods are Image Negatives Transformation (INT) method, thresholding transformations method; Gray-Level Slicing (GLS) method and Bit-Plane Slicing (BPS) method.Öğe Dietary arginine silicate inositol complex increased bone healing: histologic and histomorphometric study(Dove Medical Press Ltd, 2016) Yaman, Ferhan; Acikan, Izzet; Dundar, Serkan; Simsek, Sercan; Gul, Mehmet; Ozercan, Ibrahim Hanifi; Komorowski, JamesBackground: Arginine silicate inositol complex (ASI; arginine 49.5%, silicon 8.2%, and inositol 25%) is a novel material that is a bioavailable source of silicon and arginine. ASI offers potential benefits for vascular and bone health. Objective: The aim of this study was to evaluate the potential effects of ASI complex on bone healing of critical-sized defects in rats. Methods: The rats were randomly assigned to two groups of 21 rats each. The control group was fed a standard diet for 12 weeks; after the first 8 weeks, a calvarial critical-sized defect was created, and the rats were sacrificed 7, 14, and 28 days later. The ASI group was fed a diet containing 1.81 g/kg of ASI for 12 weeks; after the first 8 weeks, a calvarial critical-sized defect was created, and the rats were sacrificed 7, 14, and 28 days later. The calvarial bones of all the rats were then harvested for evaluation. Results: Osteoblasts and osteoclasts were detected at higher levels in the ASI group compared with the control group at days 7, 14, and 28 of the calvarial defect (P<0.05). New bone formation was detected at higher levels in the ASI group compared with the controls at day 28 (P<0.05). However, new bone formation was not detected at days 7 and 14 in both the groups (P>0.05). Conclusion: ASI supplementation significantly improved bone tissue healing in rats with critical-sized defects. This study demonstrated that ASI can enhance bone repair and has potential as a therapeutic regimen in humans.Öğe The effects of high-fat diet on implant osseointegration: an experimental study(Korean Acad Oral & Maxillofacial Surgery, 2016) Dundar, Serkan; Yaman, Ferhan; Ozupek, Muhammed Fatih; Saybak, Arif; Gul, Mehmet; Asutay, Fatih; Kirtay, MustafaObjectives: In this study, we investigated whether a high-fat diet (HFD) affected the bone implant connection (BIC) in peri-implant bone. Materials and Methods: Four male rabbits were used in this study. Dental implant surgery was introduced into each tibia, and four implants were integrated into each animal. In both the normal diet (ND) group (n=2) and HFD group (n=2), 8 implants were integrated, for a total of 16 integrated implants. The animals continued with their respective diets for 12 weeks post-surgery. Afterward, the rabbits were sacrificed, and the BIC was assessed histomorphometrically. Results: Histologic and histomorphometric analyses demonstrated that BIC was not impaired in the HFD group compared to the ND group. Conclusion: Within the limitations of this study, we found that HFD did not decrease the BIC in rabbit tibias.Öğe Effects of Systemic Propranolol Application on the New Bone Formation in Periimplant Guided Bone Regeneration(Uab Stilus Optimus, 2021) Gunes, Nedim; Gul, Mehmet; Dundar, Serkan; Artas, Gokhan; Kobat, Mehmet Ali; Tekin, Samet; Bozoglan, AlihanObjectives: The aim of this experimental animal study was to evaluate the effects of systemic propranolol on new bone formation in peri-implant bone defects. Material and Methods: Implant slots were created 4 mm long and 2.5 mm wide. After the titanium implants were placed in the sockets, 2 mm defects were created in the neck of the implants. Bone grafts were placed in these defects. Then the rats were randomly divided into three equal groups: control (n = 8), propranolol dose-1 (PRP-1) (n = 8), and propranolol dose-2 (PRP-2) (n = 8) groups. In the control group, the rats received no further treatment during the eight-week experimental period after the surgery. The rats in the PRP-1 and PRP-2 groups were given 5 mg/kg and 10 mg/kg propranolol, respectively, every three days for the eight-week experimental period after the surgery. At the end of the experimental period, the rats were euthanized. Blood serum was collected for biochemical analysis, and the implants and surrounding bone tissues were used for the histological analysis. Results: There were no significant differences in the histological analysis results and the biochemical parameters (alkaline phosphatase, calcium, creatinine and phosphorus) of the groups (P > 0.05). Also, in the test groups, there was numerically but not statistically more new bone formation detected compared with the controls. Conclusions: Within the limitations of this study, propranolol did not affect the new bone formation in peri-implant defects.Öğe Electron Microscopic and Histological Evaluation of the Levator Muscle in Patients with Congenital Blepharoptosis(Sci Printers & Publ Inc, 2016) Soker, Sevda; Cakmak, Sevin; Nergiz, Yusuf; Deveci, Engin; Gul, Mehmet; Soker, Murat; Akkus, MuratOBJECTIVE: To examine the levator muscle in patients with congenital blepharoptosis and to investigate the relationship between those findings and age, gender, and degree of blepharoptosis. STUDY DESIGN: The levator muscles of 13 congenital ptosis patients who had undergone levator muscle resection were examined by light and electron microscopy. During the preoperative period the ptosis amount, levator function, tear function, Bell's phenomenon, and jaw-wink phenomenon were evaluated. RESULTS: There were 9 (69.2%) male and 4 (30.8%) female cases, with an average age of 10.61 +/- 4.77 years (range, 4-19). The quality and quantity of the levator muscle fibrils were assessed by histological examination. There was no relationship detected between histological features of levator palpebralis superior muscle and patients' age and gender (p < 0.05). Patients with a weak levator palpebralis superior muscle had fatty degeneration histologically. Higher levator palpebralis superior muscle function correlated with decreased fatty degeneration and increased skeletal muscle fibrils, but these findings were not statistically significant. There was a reduction in the diameter of muscle fibers and nucleus deformation when muscle function was examined in patients under low-magnification electron microscope. There were lipid droplets of various sizes in some sections, and the mitochondria were seen in mitochondrial crystalline structure depending on cytopathies. In some sections of this group there was large mitochondria and edema formation due to an increase in the mitochondrial matrix. CONCLUSION: More ultrastructural studies in larger populations are needed to support the relationship between structure and function of levator palpebralis superior muscle in patients with congenital blepharoptosis.Öğe Epidemiology of atrial fibrillation in Turkey: preliminary results of the multicenter AFTER* study(Turkish Soc Cardiology, 2013) Ertas, Faruk; Kaya, Hasan; Kaya, Zekeriya; Bulur, Serkan; Kose, Nuri; Gul, Mehmet; Eren, Nihan KahyaObjectives: Although atrial fibrillation (AF) is one of the most common rhythm disorders observed in clinical practice, a multicenter epidemiological study has not been conducted in our country. This study aimed to assess our clinical approach to AF based upon the records of the first multicenter prospective Atrial Fibrillation in Turkey: Epidemiologic Registry (AFTER) study. Study design: Taking into consideration the distribution of the population in our country, 2242 consecutive patients with at least one AF attack determined by electrocardiographic examination in 17 different tertiary health care centers were included in the study. Inpatients and patients that were admitted to emergency departments were excluded from the study. Epidemiological data of the patients and the treatment administered were assessed. Results: The mean age of the patients was determined as 66.8+/-12.3 years with female patients representing 60% of the study population. While the most common AF type in the Turkish population was non-valvular AF (78%), persistent/permanent AF was determined in 81% of all patients. Hypertension (% 67) was the most common comorbidity in patients with AF. While a stroke or transient ischemic attack or history of systemic thromboembolism was detected in 15.3% of the patients, bleeding history was recorded in 11.2%. Also, 50% of the patients were on warfarin treatment and 53% were on aspirin treatment at the time of the study. The effective INR level was detected in 41.3% of the patients. The most frequent cause of not receiving anticoagulant therapy was physician neglect. Conclusion: These results demonstrate the necessity for improved quality of physician care of patients with AF, especially with regards to antithrombotic therapy.Öğe Evaluation of Effects of Topical Melatonin Application on Osseointegration of Dental Implant: An Experimental Study(Allen Press Inc, 2016) Dundar, Serkan; Yaman, Ferhan; Saybak, Arif; Ozupek, M. Fatih; Toy, Vesile Elif; Gul, Mehmet; Ozercan, I. HanifiThe aim of the present study was to evaluate the effect of local melatonin application during surgery on bone implant connection (BIC) in rabbit tibiae. Six 0.8- to 1-year-old male New Zealand rabbits were divided into 3 groups: (1) a control group (CG) in which rabbits were not treated with additive materials and only implant integration was executed; (2) a melatonin dose 1 (MLT D-1) group in which rabbits were treated with 1.2 mg of melatonin locally before implant placement into the rabbits' tibiae; and (3) a melatonin dose 2 (MLT D-2) group in which rabbits were treated with 3 mg melatonin locally before implant placement into the rabbits' tibiae. Four weeks after the procedure, the rabbits were euthanized; their tibiae were dissected from muscles and soft tissues, fixed with formaldehyde, and later embedded in methacrylate. Histologic and histomorphometric analyses were then performed under light microscopy. Following this, BIC was detected histomorphometrically, and P<.05 was considered statistically significant. Results showed that the highest BIC percentage was detected in MLT D-2, with a mean value of 39.46% +/- 0.78, as compared with a mean value of 33.89% +/- 0.92 in group MLT D-1 and 27.42% +/- 0.89 in CG. Similarly, the mean BIC percentage of the MLT D-2 group was the highest among the three, with the mean BIC percentage of the MLT D-1 still registering as higher than CG. Within the limitations of this rabbit study, it appears that local melatonin application during implant surgery may improve BIC.Öğe Investigation of the effect of combined use of alloplastic-based tricakium phosphate bone graft and antihemorrhagic plant extract (ABS) on bone regeneration in surgically induced bone defects in nondiabetic rats: an experimental animal study(Tubitak Scientific & Technological Research Council Turkey, 2018) Tanik, Abdulsamet; Guler Dogru, Arzum; Akpolat, Veysi; Acun Kaya, Filiz; Saribas, Ebru; Gul, Mehmet; Irtegun Kandemir, SevgiBackground/aim: In this experimental study, we aimed to evaluate the late period effects of the combination of Ankaferd Blood Stopper (ABS), which has bone wound healing effects, and beta-tricalcium phosphate (TCP) on the regeneration of bone tissue through histopathological, immunohistochemical, and radiological (dual energy X-ray absorptiometry - DEXA) methods in nondiabetic rats. Materials and methods: Sixty-four Wistar albino male rats were used. In the calvaria of the rats, a bone defect 7.0 mm in diameter was created. These rats were divided into 4 different groups. Group 1 was the control group without any treatment, a 0.125 mL B-TCP graft was applied to Group 2, a 0.125 mL ABS was applied to Group 3, and a 0.125 mL (beta-TCP + ABS) mixture was applied to group 4. Half of the rats were sacrificed on day 28 and the other half on day 56. Histopathological, irnmunohistochemical, and DEXA analyses of the specimens were performed after the experiment. Results: As a result of the histopathological analysis, osteoblastic activity and new bone formation were found to be significantly higher in Group 2, Group 3, and Group 4 than the control group on day 28 (P < 0.05). However, inflammatory cell infiltration and vascular dilatation and hemorrhage decreased significantly compared to the control group (P < 0.05). The histopathological analysis in rats on day 56 showed that osteoblastic activity in Group 2 and Group 4 was significantly higher than in the control group, but there was a statistically significant decrease in inflammatory cell infiltration and vascular dilatation and hemorrhage compared to the control group (P < 0.05). New bone formation in Group 2, Group 3, and Group 4 was significantly higher than in the control group. Western blotting findings revealed that the ostconectin and osteopontin expression on day 28 was increased significantly in Group 2 and Group 4. DEXA analyses revealed that BMC values in Group 2 and Group 4 on day 28 were significantly higher than in the control group (P < 0.05). There was no significant difference in bone mineral density values on the 28th and 56th days (P > 0.05). Conclusion: The use of both beta-TCP + ABS and only ABS had positive effects on wound healing and bone formation in nondiabetic rats.
