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Öğe Artificial neural networks(Ortadogu Ad Pres & Publ Co, 2007) Yazici, Ayse Canan; Oegues, Ersin; Ankarali, Seyit; Canan, Sinan; Ankarali, Handan; Akkus, ZekiArtificial neural networks (ANNs) are computer softwares that were developed by simulating the working mechanism of human brain to accomplish the basic functions of the brain. ANNs have capability to learn, remember and then generalize the data to produce new information, and to detect the relationships between variables. There are considerable relations between the statistical methods and the neural networks. In the present study, biological neural network and neurons of the human brain and the general structure of ANNs were introduced. Then ANNs' relations with the statistical methods were investigated. ANNs' advantages and disadvantages as statistical methods were discussed. Many neural networks methods are considered generalizations of some of the classical statistical techniques. Generally, in statistics ANNs are used as flexible, nonlinear regression and classification models. Many neural network architectures have close links with the nonparametric statistical methods. Results may be obtained by training the feed forward ANNs algorithms with the nonlinear models of many statistical techniques.Öğe Assessment of Bone Conduction Thresholds After Surgical Treatment in Patients with Labyrinthine Fistula(Galenos Yayincilik, 2018) Baylan, Muzeyyen Yildirim; Yilmaz, Umit; Akkus, Zeki; Topcu, IsmailObjective: This study aimed to analyze the bone conduction thresholds before and after surgery in chronic otitis media patients with cholesteatoma who had labyrinthine fistula and whose cholesteatoma matrix had been completely cleaned. Methods: The study was performed between 2013 to 2017 with 23 chronic otitis media patients who had labyrinthine fistula with cholesteatoma and who were operated at the Department of Otorhinolaryngology of Dicle University School of Medicine. Patients were assessed by anamnesis and examination and when necessary, by temporal computerized tomography and diffusion magnetic resonance imaging. Bone conduction thresholds at frequencies of 500, 1000, 2000, and 4000 Hz were determined by audiometric examination and they were compared before and after surgery. Results: Of the 23 patients, 12 were female and 11 were male; their age range was 10-55 (26.04 +/- 14.13) years. In the post-operative period, it was possible to conduct audiological follow-up on 20 patients. In these follow-ups, 16 patients showed no change in bone conduction thresholds, two patients showed worsening, and two showed improvement. When pre-and post-operative bone conduction thresholds at each frequency were compared separately, no significant difference was found (p=0.937). No statistically significant difference was found between the pre-and post-operative means at the four frequencies (p=0.712). Conclusion: In this study, we found that to reduce complications relating to cholesteatoma, it might be necessary to completely remove the matrix especially in the case of type 1 and 2 labyrinthine fistulas.Öğe Can the Density of Mineralized Dental Tissues (Dentin and Enamel) Be Measured and Compared with 3D Cone Beam Computed Tomography in Cases of Ectodermal Dysplasia?(Int Scientific Information, Inc, 2022) Yavuz, Yasemin; Akleyin, Ebru; Dogan, Mehmet Sinan; Goncharuk-Khomyn, Myroslav; Akkus, ZekiBackground: Since 3-dimensional cone beam computed tomography (CBCT) started to be used in dentistry, mineral density can now be examined with computer software from the data on the images obtained. Detailed and clear im-ages at different slice intervals can be obtained with CBCT, and mineral density can be measured from the im-age data on a computer with a Hounsfield unit (HU) scale. In addition to the broad opportunities presented by CBCT, this feature has presented a wider perspective to researchers. Material/Methods: In this study, the CBCT images obtained from patients with the genetic disorder of ectodermal dysplasia were compared with the images of a control group to determine differences in mineralization of the teeth and to show that these could be compared by measuring the mineral density of dentin and enamel tissues using the HU scale on data from CBCT images. This opens new opportunities for cognitive and implementation research. Results: In the study, CBCT images of 14 ectodermal dysplasia and 14 control group cases previously obtained for vari-ous reasons were used. Mineral density measurements were made from 4 different regions of the teeth of the ectodermal dysplasia and control groups (incisor edge of the crown, the center buccal, cervicale line, and apex of the teeth), and the groups were compared. Conclusions: The aim of this study was to provide a new overview of the feasibility and suitability of mineralization mea-surement of dentin and enamel dental tissues with CBCT in ectodermal dysplasia and control groups.Öğe Comparison of logistic regression model and classification tree: An application to postpartum depression data(Pergamon-Elsevier Science Ltd, 2007) Camdeviren, Handan Ankarali; Yazici, Ayse Canan; Akkus, Zeki; Bugdayci, Resul; Sungur, Mehmet AliIn this study, it is aimed that comparing logistic regression model with classification tree method in determining social-demographic risk factors which have effected depression status of 1447 women in separate postpartum periods. In determination of risk factors, data obtained from prevalence study of postpartum depression were used. Cut-off value of postpartum depression scores that calculated was taken as 13. Social and demographic risk factors were brought up by helping of the classification tree and logistic regression model. According to optimal classification tree total of six risk factors were determined, but in logistic regression model 3 of their effect, were found significantly. In addition, during the relations among risk factors in tree structure were being evaluated, in logistic regression model corrected main effects belong to risk factors were calculated. In spite of, classification success of maximal tree was found better than both optimal tree and logistic regression model, it is seen that using this tree structure in practice is very difficult. But we say that the logistic regression model and optimal tree had the lower sensitivity, possibly due to the fact that numbers of the individuals in both two groups were not equal and clinical risk factors were not considered in this study. Classification tree method gives more information with detail on diagnosis by evaluating a lot of risk factors together than logistic regression model. But making correct selection through constructed tree structures is very important to increase the success of results and to reach information which can provide appropriate explanations. (C) 2006 Elsevier Ltd. All rights reserved.Öğe Comparison of Vertical C/D Ratio Obtained by Assistant of Ophthalmology with Results of Optical Cohorence Tomography(Turkish Ophthalmological Soc, 2008) Sakalar, Yildirim Bayezit; Unlu, Kaan; Keklikci, Selahattin Ugur; Caca, Ihsan; Ari, Seyhmus; Balsak, Selahattin; Akkus, ZekiPurpose: To compare vertical C/D ratio that measured with ophthalmoscopic examination of second, third and fourth year assistant of ophthalmology with vertical C/D ratio obtained by optical cohorence tomography. Materials and Methods: One hundred and ten eyes of 72 glaucoma patients which are followed in glaucoma unit were included to study. Each assistant examined vertical C/D ratio by Goldman tree mirror lens and results were recorded independently from results of the other assistants. The measurements of vertical C/D ratio were obtained by optic nerve head analyses of Stratus Optical Cohorence Tomography after pupillary dilatation and vertical C/D ratio were enlisted. All measurements of vertical C/D ratio were compared each other. Results: Thirty patients were male and 42 patients were female, mean age was 51.43 +/- 19.2. Mean vertical C/D ratio measured by second year asisstant was 0.556 +/- 0.246, mean vertical C/D ratio measured by third year assistant was 0.534 +/- 0.251, mean vertical C/D ratio measured by fourth year assistant was 0.529 +/- 0.250. Mean vertical C/D ratio obtained by optical cohorence tomography was 0.651 +/- 0.223. There was no statistically signicant differences among vertical C/D ratio measured by assistants (p>0.05). The mean vertical C/D ratio that measured by each assistant was statistically lower than obtained by optical cohorence tomography (p<0.05). Conclusions: The vertical C/D ratio that measured with ophthalmoscopic examination by assistant of ophthalmology will be different from vertical C/D ratio obtained by optic nerve head analyses of optical cohorence tomography.Öğe Cone-beam dental computerize tomography for evaluating changes of aging in the dimensions central superior incisor root canals(Medicina Oral S L, 2011) Kaya, Sadullah; Adiguzel, Ozkan; Yavuz, Izzet; Tumen, Emin-Caner; Akkus, ZekiObjectives: Cone-beam dental computerize tomography (CBCT), a noninvasive imaging method, was used to image the pulp-dentin complex. Pulp changes histologically with aging. While many studies have investigated the histological changes in pulp, few studies have focused on the changes in the shape of the root canals. This study evaluated the changes in the root canals with aging of central superior teeth using CBCT. Study Design: The study examined 100 non-carious maxillary central teeth. These teeth were divided into five groups according to the age of the patients: Group A: 15-24, Group B: 25-34, Group C: 35-44, Group D: 45-54 and Group E: 55 years and older. CBCT was used to determine root length, and pulp width at the cervical, apical 1/2, and apical 1/3. Results: On comparing the groups using one-way analysis of variance (ANOVA), the root length did not differ (P > 0.05), while the pulp width at the cervical, apical 1/2, and apical 1/3 differed between the groups (P < 0.001). Conclusions: The pulp length did not change with aging, while the pulp width did change. CBCT can be used to determine the precise root length and width, to prevent iatrogenic exposure of the apex, complementing existing methods. This will improve the prediction of the prognosis of root canal treatment.Öğe Effect of electromagnetic fields and antioxidants on the trace element content of rat teeth(Dove Medical Press Ltd, 2017) Dogan, Mehmet Sinan; Yavas, Mehmet Cihan; Yavuz, Yasemin; Erdogan, Sait; Yener, Ismail; Simsek, Ibrahim; Akkus, ZekiThe purpose of this study was to examine the possible effect of extremely low-frequency electromagnetic fields (ELF-EMFs), from a high-voltage source, on rat teeth in terms of changes in trace elements (TEs) and the effect of antioxidants (melatonin [MLT] and Ganoderma lucidum [GL]) in counteracting these effects. We used adult male Wistar albino rats with a mean weight of 250-300 g and divided the rats into eight groups. The groups were subjected to an ELF- EMF that was applied with a high- voltage line for 8 hours/day for 26 days (Groups I, II, and III) or 52 days (Groups V, VI, and VII). Groups IV and VIII were the 26- and 52- day control/sham groups, respectively. Groups II and VI were treated with GL, and Groups III and VII were treated with MLT. MLT and GL were administered daily based on the weight of the animals and appropriate standards. At the end of the study, the rats were euthanized, and their anterior teeth were extracted. The teeth were preserved in pure water before evaluating the major TEs. At the end of the study, TE concentrations (in mg/kg) were assessed in the control and test groups. Compared with Group V, statistically significant differences in the concentrations of zinc (Zn) and strontium (Sr) were found for Group VII (ELF- EMF + MLT) (P< 0.05). Therefore, ELF- EMF exposure can change the content of certain TEs in teeth and, after administering MLT and GL, the values of some of the TEs return to normal.Öğe Effectiveness of ethylenediaminetetraacetic acid (EDTA) and MTAD on debris and smear layer removal using a self-adjusting file(Mosby-Elsevier, 2011) Adiguzel, Ozkan; Yigit-Ozer, Senem; Kaya, Sadullah; Uysal, Ibrahim; Ganidagli-Ayaz, Selengul; Akkus, ZekiObjective. The aim of this study was to investigate the cleaning ability of a self-adjusting file (SAF) system regarding debris and smear layer removal using ethylenediaminetetraacetic acid (EDTA) or MTAD. Study design. In total, 45 maxillary incisor teeth were randomly divided into 2 different irrigation groups of 20 canals each and a negative control group of 5 canals. The canals in each of the irrigation groups were irrigated using sodium hypochlorite (1.3%) as an initial irrigant during the first 2 minutes of operation, followed by 2 minutes continuous irrigation with either 17% EDTA or MTAD in a closed system. The negative control group was irrigated using 1.3% sodium hypochlorite. The roots were split longitudinally and subjected to scanning electron microscopy (SEM). The presence of debris and smear layer in the coronal, middle, and apical thirds of the canal was evaluated using a 5-grade scoring system with x200 and x2,000 magnification, respectively. Results. The SAF operation with 2-minute continuous irrigation using MTAD resulted in root canal walls that were free of smear layer in 85%, 70%, and 60% and of debris in 95%, 90%, and 95% of the coronal, middle, and apical thirds of the root canals, respectively. The SAF operation with continuous irrigation using EDTA resulted in root canal walls that were free of smear layer in 85%, 60%, and 50% and of debris in 95%, 90%, and 85% of the coronal, middle, and apical thirds of the root canals, respectively. Teeth in the negative control group were totally covered with debris. Evaluation by SEM showed no significant difference between the tested irrigants in removing the smear layer and debris among the different regions of the root canal. Both groups were significantly different from the negative control group. Conclusions. When using the SAF, the protocols used in this study were effective for debridement for all regions of the root canal even for the apical thirds. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011;112:803-808)Öğe An Evaluation of Preoperative Computed Tomography on Patients with Chronic Otitis Media(Springer, 2012) Yildirim-Baylan, Muzeyyen; Ozmen, Cihan Akgul; Gun, Ramazan; Yorgancilar, Ediz; Akkus, Zeki; Topcu, IsmailThis study aimed to compare the veracity of computed tomography findings on patients undergoing surgery for chronic otitis media (COM) with the surgical findings, and to determine to what extent the preoperative computerized tomography (CT) findings are useful to the surgeon. A series of 56 patients with COM undergoing preoperative CT scanning followed by surgical exploration of the middle ear and mastoid. Operative notes were recorded and data collected on the nature of soft tissue masses, the status of the ossicles, presence or absence of facial canal dehiscence and semicircular canal (SCC) dehiscence and the presence or absence of dural plate erosion, and sigmoid sinus thrombosis. Fifty-six patients were recruited in the study, 30 males and 26 females. The age range was from 16 to 67 years with a mean of 26.51 +/- A 1.4 years. The preoperative CT scan imaging in cases of cholesteatoma, ossicular chain erosion and SCC dehiscence have good correlation with the intraoperative findings. The specificity of preoperative CT scan in detecting facial canal dehiscence, dural plate erosion and sigmoid sinus thrombosis in patient of COM were weak. Preoperative computed tomography evaluation is fairly useful especially in cases of cholesteatoma. According to the results of this study, CT is of value particularly in the definition of cholesteatoma, and in determining ossicular chain erosion and semicircular canal fistula.Öğe Evaluation of the Singh index and Femur Geometry in Osteoporotic Women(Sciendo, 2010) Karabulut, Ozlen; Tuncer, Mehmet Cudi; Karabulut, Zulfu; Hatipoglu, Eyup Savas; Nazaroglu, Hasan; Akkus, ZekiWe aimed to compare the Singh index with bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA), body mass index (BMI) and femur geometry in the right proximal femur of osteoporotic women, using different statistical tests. Radiographs of each patient were assessed to determine the Singh index by five observers. The observers consisted of a consultant radiologist, physical therapist and anatomists who studied the series of radiographs. They were asked to apply the Singh index by comparing the trabecular bone pattern in the proximal right femur with the reference scale published by Singh et al. [1]. This has a six point scale from grade VI to grade I. We evaluated 47 osteoporotic women in this study. The subjects' mean age, weigth, and height were 63,21 +/- 10,106, 66,72 +/- 12.523, 154,94 +/- 7,026 respectively. We found a significant relationship between the Singh index and BMD. The Singh index correlated significantly with hip axis length, femoral neck diamater and trochanteric width. And, BMD correlated significantly with femoral head and neck diameter, femoral neck cortex width, medial calcar femoral cortex width and femoral shaft cortex width. The evaluation of the Singh index grades in its self, there was a significant relation among them.Öğe Extremely Low-Frequency Magnetic Field Decreased Calcium, Zinc and Magnesium Levels in Costa of Rat(Humana Press Inc, 2011) Ulku, Refik; Akdag, Mehmet Zulkuf; Erdogan, Sait; Akkus, Zeki; Dasdag, SuleymanElectromagnetic field (EMF) can affect cells due to biochemical change followed by a change in level of ions trafficking through membrane. We aimed to investigate possible changes in some elements in costa of rats exposed to long-term extremely low-frequency magnetic field (ELF-MF). Rats were exposed to 100 and 500 mu T ELF-MF, which are the safety standards of public and occupational exposure for 2 h/day during 10 months. At the end of the exposure period, the samples of costa were taken from the rats exposed to ELF-MF and sham. The levels of elements were measured by using atomic absorption spectrophotometry (AAS) and ultraviolet (UV) spectrophotometry. Ca levels decreased in the ELF-500 exposure group in comparison to sham group (p < 0.05). Statistically significant decrease was found in Mg levels in the ELF-500 exposure group in comparison to sham and ELF-100 exposure groups (p < 0.05). Zn levels were found to be lower in the ELF-500 exposure group than those in the sham and ELF-100 exposure groups (p < 0.05). No significant differences were determined between groups in terms of the levels of P, Cu and Fe. In conclusion, it can be maintained that long-term ELF-MF exposure can affect the chemical structure and metabolism of bone by changing the levels of some important elements such as Ca, Zn and Mg in rats.Öğe HISTOPATHOLOGIC EFFECTS OF GLASS IONOMER BONE CEMENTS APPLICATION TO MAXILLOFACIAL AREA: AN EXPERIMENTAL STUDY IN RABBITS(Diagnosis Press Ltd, 2012) Yorgancilar, Ediz; Firat, Ugur; Gun, Ramazan; Bakir, Salih; Dasdag, Suleyman; Akkus, Zeki; Gokalp, OsmanReconstruction of the maxillofacial bone defects and fractures poses a challenge to the surgeons. Various alternatives and materials have been described for these defects and fractures. Glass ionomer bone cements (GICs) have been used extensively in dentistry but recently they have also been utilized in otolaryngology. We hypothesized that GIC can be an alternative material for maxillofacial reconstruction. However, their biocompatibility is of primary importance because this material will be in direct contact with the tissue for a prolonged tune and might affect it. Therefore the aim of this study was to investigate the tissue responses to GIG in the maxillofacial area in rabbits. The study was carried out on 16 New Zealand White rabbits, which were divided into study (n: 8) and control (n: 8) groups. Experimental defects and fractures were created in the nasal bone, maxilla and zygoma in both the study and the control group. The experimental fractures and defects were reconstructed by GIG in the study group. However, the rabbits in the control group were left to natural healing process. The inflammatory reaction and fibrosis in the rabbits of both the study and the control group were compared by using descriptive histopathological analysis 180 days after application. The tissue reactions were graded. GIG showed a slight inflammatory and fibrous reaction in the rabbit of the study group. Nevertheless, statistical difference between the groups was not observed in terms of inflammatory reaction and fibrosis (P>0.05). The results of this study indicated that GIG is a well tolerated material in maxillofacial reconstruction.Öğe Influences of extremely low frequency magnetic fields on mineral and trace elements content of rat teeth(Academic Journals, 2008) Yavuz, Izzet; Akdag, M. Zulkuf; Dasdag, Suleyman; Ulku, Sabiha Zelal; Akkus, ZekiExposure to extremely low frequency magnetic fields (ELF-MF) emanating from the generation, distribution, and utilization of electricity is widespread. The major debate in recent years has focused on the possibility that exposure to ELF-MF may result in adverse health consequences. The present study was carried out to investigate the effects of ELF-MF on the mineral content in rat teeth. 27 male Sprague-Dawley rats were divided into three groups: two experimental (each, n=10), one control sham (n=7). After ELF-MF and sham exposure, some mineral levels (Ca, Mg, Zn, and P) were determined with Atomic Absorbtion Spectrophotometry (AAS). It was determined that Ca levels increased in the two experimental groups as compared to the sham group (p<.05). The levels of Ca, Mg, Zn, and P in second experimental group rats were also higher than sham group (p<.05). The results demonstrate that ELF-MF can have significant effects on teeth mineral content. Future observations and epidemiological studies of ELF-MF effects should be accompanied by laboratory experiments to evaluate oral and dental effects.Öğe IS IT NECESSARY TO PLACE URETERAL STENTING AFTER UNCOMPLICATED URETEROSCOPIC LITHOTRIPSY?(Aves, 2006) Atug, Fatih; Akay, Ferruh; Akkus, Zeki; Orgen, Sait; Alar, Salih; Sahin, HayrettinIntroduction: The routine placement of ureteral stents after ureteroscopic lithotripsy procedure is controversial. The main aim of placing a ureteral stent is to prevent ureteral obstruction and renal colic which may develop as a result of uretral edema. Additionally, stents are thought to assist the passage of residual fragments after lithotripsy through passive ureteral dilatation. However, the placement of a ureteral stent is associated with complications including stent migration, breakage, encrustation, stone formation, urinary tract infections and patient discomfort. Therefore numerous studies have been questioned the routine use of ureteral stents after uncomplicated uretroscopic lithotripsy. In this study we compared the results and stone free rates of patients with and without ureteral stenting after uncomplicated ureteroscopic lithotripsy. Materials and Methods: In this study, 367 patients who underwent ureteroscopic lithotripsy between 1996 and 2004 were evaluated retrospectively. Patients were divided into two groups. The first group consisted of 236 stented patients and the second group consisted of 132 non-stented patients. In both groups, patients were evaluated for results and stone free rates. Only uncomplicated ureteroscopy patients were included to the study. Patients with solitary kidney, history of renal failure, transplant kidney and a significant perforation or injury to ureter, high grade hydronephrosis, urinary tract infections and patients with impacted stones were excluded from the study. Additionally, patients with retrogarde stone migration were excluded from the study. The operation was performed under general anesthesia with 8.5 F rigid ureteroscope and stones were fragmented with pneumatic lithotriptor. In stented patients a double-J stent was placed in the treated ureter under fluoroscopic monitoring. In the non-stented group the safety wire was removed from the ureter and then the procedure was terminated. In stented patients, stents were removed cystoscopically under local or general anesthesia. Results: The mean age of patients was 40.1 years (range 22 to 76) in the stented group and 37.8 (range 19 to 65) in the non-stented group. The mean stone size was 9.1 mm (range 4 to 21) and 7.8 mm (range 3 to 17) in the in the stented and nonstented patients, respectively. There was no statistical difference between stone free rates in both groups. The stone free rate was %92.4 in stented group and %90.8 in the non-stented group (p>0.05). However, there was statistically significant difference for operative times between the two groups. The mean operative time was 51.4 min (range 30 to 110) in the stented group and 40.2 min. in the non-stented group (range 25 to 70) (p<0.05). The mean operative times increased 28% in the stented group. The symptoms of urinary frequency, flank pain, urgency and dysuria were more common and severe in the stented group. Additionally, hematuria was more severe and prolonged in stented patients when compared to non-stented patients. Conclusion: Our results demonstrate that it is not necessary to place uretral stent after uncomplicated ureteroscopic pneumatic lithotripsy. There was no difference between nonstented and stented patients with respect to stone free status. Ureteral stent placement following uncomplicated lithotripsy augments the operation time, surgical cost and increases patient morbidity.Öğe Measuring Bone Density in Healing Periapical Lesions by Using Cone Beam Computed Tomography: A Clinical Investigation(Elsevier Science Inc, 2012) Kaya, Sadullah; Yavuz, Izzet; Uysal, Ibrahim; Akkus, ZekiIntroduction: Differences in bone density before and after endodontic treatment were examined in teeth with periapical lesions in Hounsfield units (HUs) by using cone beam computed tomography (CBCT). Methods: Sixteen patients requiring endodontic treatment for periapical lesions underwent CBCT scan before and after treatment. Their bone densities were calculated in HUs. The study included 16 lesions measuring 8-10 mm in diameter. HU measurements were taken from an area of 2.25 mm(2) on the CBCT images where the bone density was lowest, before and after treatment. Results: The initial and final measurements were compared statistically by using paired samples statistics at the 5% significance level. Conclusions: The results of this study support the use of CBCT to measure bone density before and after endodontic treatment. (J Endod 2012;38:28-31)Öğe Patient-specific factors in the proximity of the inferior alveolar nerve to the tooth apex(Medicina Oral S L, 2012) Adiguzel, Ozkan; Yigit-Ozer, Senem; Kaya, Sadullah; Akkus, ZekiObjectives: To evaluate whether age and gender differences are predictive factors for inferior alveolar nerve position with respect to mandibular first molar roots. Study Design: Cone-beam computed tomography scans [0.2-mm(3) voxel size; n = 200 (100 males, 100 females)] of patients aged 15-65 years showing mandibular first and second molars were included in this study. Patients with pathoses that might affect inferior alveolar nerve position, including second molar and/or first premolar extraction, were excluded. Fourteen measurements (mm) were taken from the inferior alveolar nerve to the mesial and distal root apices. Subjects were grouped by age and gender. Data were analysed using two-way analyses of variance with post hoc Bonferroni corrections. Results: The distance from the inferior alveolar nerve to the root apices was smaller in females than males, regardless of age (p < 0.01). Distal roots were closer to the nerve than mesial roots in both genders (p < 0.05). Total buccolingual mandibular length (at 3-mm apical level) was shorter in females than males (p < 0.01) but mean buccolingual mandibular width at the level of the inferior alveolar canal did not differ. Nerve-root apex distances were significantly shorter in males and females aged 16-25 and 56-65 years than in other age groups (p < 0.01). Conclusions: The distance between inferior alveolar nerve and mandibular first molar roots depends upon the age and gender: it is shorter in females than in males and in subjects aged 16-25 years and >55 years than in other age groups.Öğe The relationship between pneumatized middle turbinate and the anterior ethmoid roof dimensions: a radiologic study(Springer, 2013) Gun, Ramazan; Yorgancilar, Ediz; Bakir, Salih; Ekici, Faysal; Akkus, Zeki; Ari, Seyhmus; Topcu, IsmailThe development of pneumatized middle turbinate may affect anterior ethmoid roof formation. The aim of this study was to investigate the relationship between the pneumatized middle turbinate and the dimensions of the anterior skull base structures using computed tomography scans. The coronal reconstructed images of the computed tomography scans were evaluated retrospectively. The lateral and medial ethmoid roof points, the width of the cribriform plate (CP), and the anterior ethmoid roof were identified at the first coronal cut, which was determined by the infraorbital nerve. The pneumatized middle turbinates were measured on the axial, vertical, and sagittal planes. The images of 101 patients were evaluated. The mean axial diameters of the pneumatized middle turbinate on the right and left sides were between 6.93 and 4.95 mm, respectively. The correlation between the axial diameters of the pneumatized middle turbinate and the width of the anterior ethmoid roof (termed AER width) was significant for both sides and gender (p < 0.05). There was a higher correlation on the right side where the pneumatized middle turbinate was observed more frequently (r = 0.357). The relationship between CP width and the diameters of the pneumatized middle turbinate was not significant (p > 0.05) for both sides. Iatrogenic lesions of the skull base occur predominantly in the lateral lamella of the CP. The risk of this complication may decrease with increasing of the AER width. Pneumatized middle turbinate may cause an increase in the width of the anterior ethmoid roof and provide more reliable endoscopic intervention of the anterior skull base and frontal sinus.Öğe Three-dimensional evaluation of maxillary sinus volume in different age and sex groups using CBCT(Springer, 2019) Belgin, Ceren Aktuna; Colak, Mehmet; Adiguzel, Ozkan; Akkus, Zeki; Orhan, KaanAim Sinus maxillaris is an important anatomical formation in many branches of dentistry due to its proximity to the field of work. Various methods have been used in literature to measure the maxillary sinus volume (MSV) such as cadavers, stereology, two-dimensional conventional radiographs, computed tomography (CT), magnetic resonance imaging (MRI). The aim of this study is to evaluate the change of maxillary sinus volume according to age and gender with MIMICS 19.0 (Materialise HQ Technologielaan, Leuven, Belgium) which is one of three-dimensional modeling software. Materials and methods This study was performed in 200 patients selected by a retrospective review of the archives of the Dicle University, Faculty of Dentistry, Department of Oral and Maxillofacial Radiology. Patients were divided into five age groups (18-24 years, 25-34 years, 35-44 years, 45-54 years, and >= 55 years) and by sex. Cone-beam computed tomography (CBCT) images of the patients were transferred to the MIMICS software and the MSV was measured. All statistical analyses were performed using the SPSS (Statistical Package for Social Sciences, version 21) software. Results There was no statistically significant difference between the right and left maxillary sinus volume according to the findings obtained from our study, and maxillary sinus volume in males was found to be significantly higher than that of females. Another finding of our study is that the maxillary sinus volume decreases with age increase. Especially it was also found that the sinus volume in males in the 18-24 age group was statistically significantly higher than females. Conclusion Consequently, maxillary sinus volume measurements can be made on CT, CBCT, MRI scans using reconstruction software.