The influence of the implant-abutment complex on marginal bone and peri-implant conditions: A retrospective study

Tokgoz, Selen Ergin,Bilhan, Hakan The Korean Academy of Prosthodonitics 2021 The Journal of Advanced Prosthodontics Vol.13 No.1

Purpose. The design of the implant-abutment complex is thought to be responsible for marginal bone loss (MBL) and might affect the condition of the peri-implant tissues. This the present study aimed to evaluate the influence of the implant-abutment complex on MBL and the peri-implant tissues in partially edentulous patients treated with dental implants and determine the most advantageous design. Materials and Methods. A total of ninety-one endosseous implants with different designs of implant-abutment complex [tissue level-TL (n = 30), platform switch-PS (n = 18), and platform match-PM (n = 43)] were reviewed for MBL, Probing Pocket Depth (PPD) and Bleeding on Probing (BoP). MBL was calculated for first year of the insertion and the following years. Results. The median MBL for the PM implants (2.66 ± 1.67 mm; n = 43) in the first year was significantly higher than those for the other types (P=.033). The lowest rate of MBL (0.61 ± 0.44 mm; n = 18) was observed with PS implants (P=.000). The position of the crown-abutment border showed a statistically significant influence (P=.019) and a negative correlation (r=-0.395) on MBL. BoP was found significantly higher in PM implants (P=.006). The lowest BoP scores were detected in PS implants, but the difference was not significant (P=.523). The relation between PPD and connection type revealed no statistically significant influence (P>.05). Conclusion. Within the limitations of the present study, it may be concluded that PS implants seem to show better peri-implant soft tissue conditions and cause less MBL.

A Neuro-Behçet's Case Operated with the Intracranial Mass Misdiagnosis

Tokgoz, Osman Serhat,Akpinar, Zehra,Guney, Figen,Seyithanoglu, Abdullah The Korean Neurosurgical Society 2012 Journal of Korean neurosurgical society Vol.52 No.5

Behçet's disease (BD) is an inflammatory systemic disorder with oral and genital ulcers, as well as ophthalmologic and cutaneous symptoms. Neurological manifestations in BD represent between 2.2% to 50% of the cases. The 25-year-old male patient, diagnosed with BD three years earlier, was admitted to our clinic with complaints of recurrent headaches. Tumor-like-parenchimal involvement was detected on a cranial magnetic resonance imaging. The lesion was removed surgically and then he suffered from right hemiparesis and epilepsy. Pathological examination of the lesion noted a demyelinating non-tumoural etiology. A neuro-Beh$\check{g}$et's case with parenchymal involvement has been examined in light of the literature, in terms of a tumor and a demyelinating disease differential diagnosis.

Experimental tests on biaxially loaded concrete-encased composite columns

Serkan Tokgoz,Cengiz Dundar 국제구조공학회 2008 Steel and Composite Structures, An International J Vol.8 No.5

This paper reports an experimental investigation of the behaviour of concrete-encased composite columns subjected to short-term axial load and biaxial bending. In the study, six square and four L-shaped cross section of both short and slender composite column specimens were constructed and tested to examine the load-deflection behaviour and to obtain load carrying capacities. The main variables in the tests were considered as eccentricity of applied axial load, concrete compressive strength, cross section, and slenderness effect. A theoretical procedure considering the nonlinear behaviour of the materials is proposed for determination of the behaviour of eccentrically loaded short and slender composite columns. Two approaches are taken into account to describe the flexural rigidity (EI) used in the analysis of slender composite columns. Observed failure mode and experimental and theoretical load-deflection behaviour of the specimens are presented in the paper. The composite column specimens and also some composite columns available in the literature have been analysed and found to be in good agreement with the test results.

Are Spinal or Paraspinal Anatomic Markers Helpful for Vertebral Numbering and Diagnosing Lumbosacral Transitional Vertebrae?

Nil Tokgoz,Murat Ucar,Aylin Billur Erdogan,Koray Kilic,Cahide Ozcan 대한영상의학회 2014 Korean Journal of Radiology Vol.15 No.2

Objective: To evaluate the value of spinal and paraspinal anatomic markers in both the diagnosis of lumbosacral transitional vertebrae (LSTVs) and identification of vertebral levels on lumbar MRI. Materials and Methods: Lumbar MRI from 1049 adult patients were studied. By comparing with the whole-spine localizer, the diagnostic errors in numbering vertebral segments on lumbar MRI were evaluated. The morphology of S1–2 disc, L5 and S1 body, and lumbar spinous processes (SPs) were evaluated by using sagittal MRI. The positions of right renal artery (RRA), superior mesenteric artery, aortic bifurcation (AB) and conus medullaris (CM) were described. Results: The diagnostic error for evaluation of vertebral segmentation on lumbar MRI alone was 14.1%. In lumbarization, all patients revealed a well-formed S1–2 disc with squared S1 body. A rhombus-shaped L5 body in sacralization and a rectangular-shaped S1 body in lumbarization were found. The L3 had the longest SP. The most common sites of spinal andparaspinal structures were: RRA at L1 body (53.6%) and L1–2 disc (34.1%), superior mesenteric artery at L1 body (55.1%) and T12–L1 disc (31.6%), and AB at L4 body (71.1%). CM had variable locations, changing from the T12–L1 disc to L2 body. They were located at higher sacralization and lower lumbarization. Conclusion: The spinal morphologic features and locations of the spinal and paraspinal structures on lumbar MRI are not completely reliable for the diagnosis of LSTVs and identification on the vertebral levels.

Test and analysis of concrete-filled double steel and double skin tubular columns having outer stainless steel tube

Serkan Tokgoz,Sedat Karaahmetli,Cengiz Dundar 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.45 No.1

This paper presents experimental and analytical studies of eccentrically loaded concrete-filled double steel (CFDST) and concrete-filled double skin tube (DCFST) columns having outer stainless steel tube. Eighteen CFDST and DCFST column specimens were manufactured and tested to examine the strength and load-deflection responses. In the study, the main parameters were concrete strength, load eccentricity, cross section and slenderness. The strengths, load-deflection diagrams and failure patterns of the columns were observed. In addition, the tested CFDST and DCFST columns were analyzed to attain the capacity and load versus lateral deflection responses. The obtained theoretical results were compared with the test results. A parametric study was also performed to research the effects of the ratio of eccentricity (e/Ho) slenderness ratio (L/r), Ho/to ratio, Hi/ti ratio and the concrete compressive strength on the behavior of columns. In this work, the obtained results indicated that the ductility and capacity of columns were affected by cross section, concrete strength, steel strength, loading eccentricity and slenderness.

Strength of biaxially loaded high strength reinforced concrete columns

Dundar, Cengiz,Tokgoz, Serkan Techno-Press 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.44 No.5

An experimental research was conducted to investigate the strength of biaxially loaded short and slender reinforced concrete columns with high strength concrete. In the study, square and L-shaped section reinforced concrete columns were constructed and tested to obtain the load-deformation behaviour and strength of columns. The test results of column specimens were analysed with a theoretical method based on the fiber element technique. The theoretical ultimate strength capacities and the test results of column specimens have been compared and discussed in the paper. Besides this, observed failure mode and experimental and theoretical load-lateral deflection behaviour of the column specimens are presented.

A study on load-deflection behavior of two-span continuous concrete beams reinforced with GFRP and steel bars

Unsal, Ismail,Tokgoz, Serkan,Cagatay, Ismail H.,Dundar, Cengiz Techno-Press 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.63 No.5

Continuous concrete beams are commonly used as structural members in the reinforced concrete constructions. The use of fiber reinforced polymer (FRP) bars provide attractive solutions for these structures particularly for gaining corrosion resistance. This paper presents experimental results of eight two-span continuous concrete beams; two of them reinforced with pure glass fiber reinforced polymer (GFRP) bars and six of them reinforced with combinations of GFRP and steel bars. The continuous beams were tested under monotonically applied loading condition. The experimental load-deflection behavior and failure mode of the continuous beams were examined. In addition, the continuous beams were analyzed with a numerical method to predict the load-deflection curves and to compare them with the experimental results. Results show that there is a good agreement between the experimental and the theoretical load-deflection curves of continuous beams reinforced with pure GFRP bars and combinations of GFRP and steel bars.

A study on load-deflection behavior of two-span continuous concrete beams reinforced with GFRP and steel bars

Ismail Unsal,Serkan Tokgoz,Ismail H. Cagatay,Cengiz Dundar 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.63 No.5

Continuous concrete beams are commonly used as structural members in the reinforced concrete constructions. The use of fiber reinforced polymer (FRP) bars provide attractive solutions for these structures particularly for gaining corrosion resistance. This paper presents experimental results of eight two-span continuous concrete beams; two of them reinforced with pure glass fiber reinforced polymer (GFRP) bars and six of them reinforced with combinations of GFRP and steel bars. The continuous beams were tested under monotonically applied loading condition. The experimental load-deflection behavior and failure mode of the continuous beams were examined. In addition, the continuous beams were analyzed with a numerical method to predict the load-deflection curves and to compare them with the experimental results. Results show that there is a good agreement between the experimental and the theoretical load-deflection curves of continuous beams reinforced with pure GFRP bars and combinations of GFRP and steel bars.

Strength of biaxially loaded high strength reinforced concrete columns

Cengiz Dundar,Serkan Tokgoz 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.44 No.5

An experimental research was conducted to investigate the strength of biaxially loaded short and slender reinforced concrete columns with high strength concrete. In the study, square and L-shaped section reinforced concrete columns were constructed and tested to obtain the load-deformation behaviour and strength of columns. The test results of column specimens were analysed with a theoretical method based on the fiber element technique. The theoretical ultimate strength capacities and the test results of column specimens have been compared and discussed in the paper. Besides this, observed failure mode and experimental and theoretical load-lateral deflection behaviour of the column specimens are presented.

A Case of Pneumothorax after Phrenic Nerve Block with Guidance of a Nerve Stimulator

Beyaz, Serbulent Gokhan,Tufek, Adnan,Tokgoz, Orhan,Karaman, Haktan The Korean Pain Society 2011 The Korean Journal of Pain Vol.24 No.2

Hiccups have more than 100 etiologies. The most common etiology has gastrointestinal origins, related mainly to gastric distention and gastroesophageal reflux disease. Intractable hiccups are rare but may present as a severe symptom of various diseases. Hiccups are mostly treated with non-invasive or pharmacological therapies. If these therapies fail, invasive methods should be used. Here, we present a patient on whom we performed a blockage of the phrenic nerve with the guidance of a nerve stimulator. The patient also had pneumothorax as a complication. Three hours after intervention, a tube thoracostomy was performed. One week later, the patient was cured and discharged from the hospital. In conclusion, a stimulator provides the benefit of localizing the phrenic nerve, which leads to diaphragmatic contractions. Patients with thin necks have more risk of pneumothorax during phrenic nerve location.