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Öğe Can ultrasonography be used to detect root perforation? An in vitro study(Wiley, 2025) Sarıyılmaz, Öznur; Eren, İrem; Sarıyılmaz, Evren; Eren, Hakan; Uslu, GülşahThis study assessed the usability of ultrasonography in detecting root canal perforations. The buccal side of incisor root were perforated. The actual lengths up to the perforation site were measured by visualisation of the tip of a file. Specimens were embedded in gypsum, and it was scraped to simulate bone resorption. Resorption cavities were filled with ultrasound gel. Measurements were taken by advancing a file through the canal until the tip became visible in the ultrasound image. 3D scans were obtained using cone-beam computed tomography (CBCT) and the distance between the coronal point of the resorption cavity and the reference point was measured. The actual distance of the resorption cavity from the reference point varied 6-10.6 mm. The same distances were measured via ultrasound as 5.7-10.9 mm, while measured using CBCT 6-10.5 mm. No significant differences were found. Ultrasonography shows promise for detecting root perforations, however further research is needed.Öğe Can ultrasonography be used to determine working length in endodontic treatment? An in vitro study(Springer, 2024) Eren, İrem; Sarıyılmaz, Öznur; Eren, Hakan; Sarıyılmaz, Evren; Uslu, GülşahThis study was conducted to evaluate efficacy of ultrasonography (USG) in determining working length in in-vitro conditions. Twenty five access cavities of maxillary incisor teeth were opened and actual working lengths (AWL) were measured with dental operating microscope. The working length were then measured with an electronic apex locator and USG. USG and apex locator measurements were statistically analyzed using one sample t-test and compared with AWL. The mean AWL measurment was 20.68 mm. USG measured the working length slightly longer (21.09 mm) than the measurements of apex locator (20.64 mm). Statistical analysis showed that the USG method provided similar measurements to electronic apex locators and with no statistical difference with actual working length (P < .05). USG emerges as a promising method for working length measurement that allows simultaneous visualization of root tip anatomy in cases where electronic apex locators may be insufficient and there is buccal cortical bone loss.Öğe Comparison of CBCT radiation doses with conventional radiographs in TMJ imaging using Monte Carlo simulations(Springer Science and Business Media Deutschland GmbH, 2024) Deniz, Yeşim; Eren, Hakan; Sessiz, Rüya; Coşan Ata, GamzeThree-dimensional imaging methods are widely used for evaluation of bony changes of temporomandibular joint (TMJ). Besides, lateral and posterio-anterior TMJ projections in both closed- and open-jaw positions for each temporomandibular joint are used as two-dimensional diagnostic tools. The purpose of the present study was to compare effective and mean organ absorbed doses of plain radiography techniques with those of different modalities of cone beam computed tomography (CBCT) scanning of an adult’s temporomandibular joint. PCXMC 2.0 software was used to calculate mean organ and effective doses. A NewTom CBCT device (Newtom 5G XL; QR systems; Verona, Italy) was simulated at 360° rotation using a 6 × 6 cm2 FOV in standard and high-resolution modes. Lateral and posterio-anterior TMJ plain projections were simulated according to recommendations of the manufacturer of the Planmeca ProMax® 2D S3 device. Doses for both projections were simulated with Monte Carlo methods and the International Commission on radiological protection adult reference computational phantoms. The highest mean organ absorbed doses occurred in bone surfaces, salivary glands, and skull for posterio-anterior TMJ and lateral TMJ, and for CBCT scanning in all examinations. The effective doses of posterio-anterior and lateral TMJ plain radiographs were found to be higher than those of the Standard Mode-Eco Scan CBCT. Therefore, the lowest effective dose was calculated in Standard Mode-Eco Scan CBCT. It is concluded that NewTom 5G XL Standard Mode-Eco Scan CBCT can be used instead of plain radiographs (lateral and posterio-anterior TMJ) in temporomandibular joint imaging as it allows visualizing the three-dimensional structure of the temporomandibular joint as an advantage.Öğe Comparison of pediatric doses of cone beam computed tomography and panoramic radiography in three age groups(Novin Medical Radiation Institute, 2025) Eren, Hakan; Deniz, Yeşim; Ata, G.C.; Sessiz, RüyaBackground: A wide variety of radiation dose values can occur in Cone Beam Computed Tomography (CBCT) devices with different field of view (FOV) sizes. Radiation dose of current CBCT devices have been considerably reduced. This study compared effective radiation doses and organ absorption doses obtained from panoramic and CBCT imaging at various FOV sizes in children aged five, ten, and fifteen years. Materials and Methods: To calculate the organ doses and effective doses, a dose calculation software PC-based Monte Carlo (PCXMC) 2.0 based on Monte-Carlo simulation was used for CBCT and panoramic exposures. Both absorbed and effective doses were calculated for the simulated phantoms of 5, 10 and 15 years old separately. Results: The organ doses of thyroid and salivary glands measured with 6*6 ECO Scan CBCT were found to be lower when compared with panoramic radiography organ doses. Panoramic radiography effective doses were lower than all other CBCT modes in all age groups. Conclusion: Although it is stated that this study does not have diagnostic data, it is thought that 6×6 ECO Scan Mode of Newtom CBCT can be chosen instead of panoramic radiography in children aged 5 years due to the dose differences. © 2025 Novin Medical Radiation Institute. All rights reserved.Öğe Do the Alterations in Eyelid and Conjunctival Flora Lead to Streptococcal Endophthalmitis in Glaucoma Patients?(Turkish Ophthalmological Soc, 2010) Eser, Ilker; Beskoc, Melike; Erdogan, Hawa; Nakipoglu, Yasar; Eren, Hakan; Aydin, Derya; Yilmaz, Omer F.Purpose: To compare the eyelid and conjunctival flora of glaucoma patients with normal subjects. Material and Method: One hundred and thirty-two eyes of 83 patients were assigned to 4 groups, consisting of 33 eyes each. Group 1 consisted of eyes which underwent trabeculectomy without need for postoperative antiglaucoma drops (AGD), group 2 consisted of eyes which needed to use AGD following the trabeculectomy, group 3 consisted of eyes which did not undergo trabeculectomy but used AGD, and group 4, the control group, consisted of healthy eyes. All AGD contained benzalkonium chloride (BAC) as a preservative. Results: A statistically significant difference was found between the group using AGD and the control group, regarding the number of coagulase-negative staphylococci isolated from eyelid specimens (p=0.03). Although the isolation rates of Streptococcus spp. and Haemophilus spp. were higher in groups 1, 2 and 3 than in the control group for the conjunctival specimens, the difference was not statistically significant (p=0.87, p=0.29, respectively). Discussion: Trabeculectomy together with long-term use of AGD, or long-term use of AGD with BAC itself, seemed to decrease the number of coagulase-negative Staphylococci and to increase the number of Streptococcus spp. and Haemophilus spp. in the eyelid and conjunctival flora of the control group. As Streptococcus spp. predominate in cases of delayed-onset bleb-associated endophthalmitis, by taking eyelid and conjunctiva specimens for culture at certain intervals, their eradication might be achieved and therefore, the potentially devastating endophthalmitis might be prevented.Öğe Evaluation of the differences in the localization of the lingula mandibulae according to pubertal development in children: A new anthropological and forensic approach(Elsevier Ltd, 2024) Eren, Hakan; Sezer, Berkant; Deniz, YeşimObjective: This study aims to investigate changes in lingula mandibulae localization before and after puberty and sex differences. Design: 288 panoramic radiographs evaluated retrospectively were divided into four groups according to pubertal development: under and over 10 years old for females and under and over 11 years old for males. Four anatomic sites were used as reference points: (a) the anterior border of the ramus; (b) the posterior border of the ramus; (c) the deepest point of mandibular notch; and (d) the angulus mandibulae. The ratio of the distances from the lingula mandibulae to points (a) and (b) and the ratio of the distances from the lingula mandibulae to points (c) and (d) were determined. Two-way ANOVA was performed to assess differences between subgroups based on sex and puberty, and a Bonferroni post-hoc test was performed for multiple comparisons. Results: Puberty and sex has a significant interaction effect on the vertical location of the lingula mandibulae. Postpubertal lingula mandibulae is positioned proportionally more anteriorly by prepubertal localization. In addition, the lingula mandibulae is situated more posteriorly in females compared to males. A significant interaction effect of puberty and sex was observed in relation to the vertical positioning of the lingula mandibulae. Conclusions: The spatial localization of the lingula mandibulae and its spatial displacement with age can be used both in estimating sex and the onset of puberty. Changes in the localization of lingula mandibulae according to pubertal development and sex can be used in forensic and anthropological contexts.Öğe Evaluation of The Frequency of Artifacts in CBCT Depending on The Different Size of Field of View(Marmara University, 2023) Polat, Elif; İncebeyaz, Burak; Deniz, Hatice Ahsen; Eren, HakanABSTRACT Objectives: Various artifacts can be encountered when examining Cone-beam computed tomography(CBCT) images. In recent years, no descriptive study has been conducted on CBCT artifacts in the literature. The aim of this study is to identify artifacts in CBCT images with different imaging fields (FOV) taken on the same device, to determine their frequency, and also to reveal artifacts that are little known in the literature. Materials and Methods: In the study, CBCT images of the Faculty of Dentistry between the years 2012-2021 were scanned retrospectively and a total of 359 Cone Beam Computed Tomography images with 50x55, 100x55, 100x90, 130x55, 130x90, 230x170, 230x270 imaging fields (FOV) in the database, which met the exclusion and inclusion criteria, were analyzed by three oral and maxillofacial radiology research assistants and the types of artifacts seen on these images were determined. The incidence of the identified artifact types in the specified imaging areas was evaluated. Results: When looking at all images, the most common errors, regardless of FOV, were inevitable artifacts. Aliasing and motion artifacts were seen at higher rates on CBCT images with a larger field of view. In addition, the ring artifact was encountered in CBCT images with high imaging fields such as 130x90, 230x170 and 230x270. Conclusion: To know the incidence and causes of artifacts in images; it will prevent the patient, the environment and the practitioner from receiving x-rays (radiation) unnecessarily, mixing these errors with different pathological conditions and repetition of the imageÖğe Glokom hastalarında sıklıkla görülen streptokok endoftalmilerine, kirpik ve konjonktiva florası(2010) Eser, İlker; Beşkoç, Melike; Erdoğan, Havva; Nakipoğlu, Yaşar; Eren, Hakan; Aydın, Derya; Yılmaz, Ömer F.Amaç: Glokom hastalarının kirpik ve konjonktiva floralarını normal bireylerle karşılaştırmak. Gereç ve Yöntem: Her bir grupta 33 göz olmak üzere 83 hastanın 132 gözü çalışmaya dahil edildi. Grup 1; trabekülektomi uygulanmış ve ameliyat sonrası anti-glokomatöz damlalara (AGD) ihtiyaç duyulmayan, Grup 2; trabekülektomi sonrası AGD kullanmaya devam eden, Grup 3; trabekülektomi uygulanmamış fakat AGD kullanan gözlerden, Grup 4 ise sağlıklı gözleri içeren kontrol grubundan oluşturuldu. Bütün AGD’lar koruyucu olarak benzalkonyum klorid (BAK) içermekteydi. Sonuçlar: Alınan kirpik kültürlerinde; AGD kullanan gruplar ve kontrol grubu arasında izole edilen koagülaz negatif stafilokokların sayısı bakımından anlamlı bir fark saptandı (p=0,03). Alınan konjonktiva kültürlerinde ise; grup 1, 2 ve 3’de Streptococcus türleri ve Haemophilus türleri izolasyon oranlarının yüzdeleri kontrol grubuna göre daha yüksek bulundu fakat istatistiksel olarak anlamlı değildi, sırasıyla (p=0,87 ve p=0,29). Tartışma: Trabekülektomi ile birlikte uzun süreli AGD kullanımı veya tek başına uzun süreli AGD kullanımı konjonktiva ve kirpik floralarında bulunan koagülaz negatif stafilokokların sayısını azaltırken, Streptococcus türü ve Hemophilus türü bakterilerin sayısını da arttırmaktadır. Geç başlangıçlı bleble ilişkili endoftalmilerde Streptococcus türleri en yaygın bakteriler olduğundan, kötü prognozlu endoftalmilerin azaltılmasında, kirpik ve konjonktivadan belli aralıklarla kültür alınarak bu bakterilerin eradike edilmesinin faydalı olabileceğini düşünmekteyiz.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 Long-term evaluation of masseter muscle activity, dimensions, and elasticity after orthognathic surgery in skeletal class III patients(Springer Science and Business Media Deutschland GmbH, 2023) Müftüoğlu, Özge; Aktürk, Ezgi Sunal; Eren, Hakan; Görürgöz, Cansu; Karasu, Hakan Alpay; Orhan, Kaan; Akat, Bora; Memikoğlu, Tulin Ufuk ToygarObjective: To evaluate changes in the masseter muscle after orthognathic surgery using electromyography (EMG), ultrasonography (US), and ultrasound elastography (USE) in individuals with skeletal class III anomaly over long-term follow-up and compare with a control group. Materials and methods: The study group included 29 patients with class III dentofacial deformities scheduled to undergo orthodontic treatment and orthognathic surgery. The control group included 20 individuals with dental class I occlusion. Assessment of the masseter muscles using EMG, US, and USE was performed before orthognathic surgery (T1) and at postoperative 3 months (T2) and 1 year (T3) in the study group, and at a single time point in the control group. All assessments were performed at rest and during maximum clenching. Masseter muscle activity, dimension, and hardness were analyzed. Results: Electromyographic activity of the masseter muscle during maximum clenching was increased at postoperative 1 year but did not reach control group values. On ultrasonography, the masseter muscle showed minimal changes in dimension at postoperative 1 year compared to preoperative values and remained below control group values. The postoperative increase in masseter muscle hardness at rest and during maximum clenching persisted at postoperative 1 year. Conclusion: The results of this study suggest that after orthognathic surgery, additional interventions and much longer follow-up are needed to ensure better muscle adaptation to the new occlusion and skeletal morphology. Clinical relevance: All assessment methods are useful for comprehensively evaluating changes in the masticatory muscles after orthognathic surgery.Öğe New Classi?cation of Intraoral Phosphor Plate Artifacts Based on Literature Review(2022) İncebeyaz, Burak; Eren, Hakan; Öztaş, BengiArtifacts (error) encountered in phosphor plates (PSP) used in intraoral digital imaging were evaluated under a new classi?cation.\rIn this review, when obtaining images with intraoral phosphor plates, artifacts before, during, after the irradiation and artifacts\rcaused by the scanner were determined according to the review of the literature. Intraoral radiographs are obtained while many\rartifacts are encountered. These artifacts can occur in both conventional and digital systems. Artifacts that occur before irradiation\rsuch as scratches, cracks, ?ngerprints, dust particles, bite marks, plate edge peeling; during irradiation such as positioning error,\rmotion artifact, shooting from different angles errors, cone-cut, double image, light-dark images, glare, fading, revers\rirradiation, refraction, distortion; after irradiation such as irregular image density, noise, writing artifact, ?ngerprints, fading\rartifacts; and depending on the scanner artifacts such as inclined placement, a parallel line to scan direction, dust fragment, plate\rsize determination error has been shown to be visible. An inaccurate image with no diagnostic value requires regeneration. For\rthis reason, knowing the causes of artifacts in radiographic images is important for the patient, the environment, and the\rpractitioner to prevent unnecessary x-rays (radiation).Öğe ORAL SQUAMOUS CELL CARCINOMA OF TONGUE IN A YOUNG WOMAN WITH LOW RISK: A CASE REPORT(2023) Polat, Elif; Eren, Hakan; Özlü, Mert; Gökçen, Mustafa Kürşat; Tüzüner, Ayşegül MineThe increase in the incidence of squamous cell carcinoma in the lateral part of the tongue in young, non-smoking and female individuals in recent years and the fact that HPV and other viral factors remain etiologically unclear in these cancers indicate that different etiopathologies should be investigated in lateral SCC of the tongue. The case is the first reported case of OSCC after orthodontic treatment in a low-risk young female patient.Öğe Prevalence and Pattern of Stylohyoid Chain Complex on Panoramic Radiographs: A Retrospective Study(Marmara Univ, Inst Health Sciences, 2022) Altindag, Ali; Eren, Hakan; Kucukkalem, Muhammed Feyzi; Altindag, OmerObjective: The elongated styloid process (SP) and calcified stylohyoid ligament can be evaluated radiologically and are associated with some symptoms and syndromes. This study aimed to define the incidence of different stylohyoid chain patterns and classify them. Methods: Digital panoramic radiographs of 1217 patients were included in the study. The styloid chain patterns were analyzed according to MacDonald-Jankowski's study. Data analysis was performed using the IBM SPSS Statistics 21.0 (Statistical Package for Social Sciences) program. Descriptive values were analyzed by using descriptive statistics. The data were assessed by using Chi-squared tests. A probability level of less than.05 (p..05) was considered significant. Results: The prevalence of the stylohyoid chain complex patterns was higher for normal SP (86.5%), followed by elongated SP (7.1%), calcified stylohyoid ligament (2.2%), and absent stylohyoid chain (2.8%). Unclassified SP was detected in twenty individuals on the left (1.6%) and fourteen on the right (1.2%). In view of symmetry of the stylohyoid chain complex, 979 (80.4%) were symmetric, 238 (19.6%) were asymmetric and 14 (1.15%) of the asymmetrical ones were unilateral. There was no significant difference in gender for the type of stylohyoid chain complex pattern (p >.05). There was statistically significant difference between the stylohyoid complex pattern and age groups for the right and left sides (p <.05). Conclusion: The authors believe that this study provides additional information about the frequency of the elongated styloid process and provides valuable knowledge of the anatomical variations of the SP. Current findings should be correlated with clinical symptoms in future studies.Öğe The evaluation of the relationship between changes in masseter muscle thickness and tooth clenching habits of bruxism patients treated with botulinum toxin A(Wolters Kluwer Medknow Publications, 2023) Erdil, Deniz; Bağış, Nilsun; Eren, Hakan; Camgöz, Melike; Orhan, KaanBackground: Bruxism is defined as recurrent masticatory muscle activity. Although there is not an agreed treatment method for bruxism, the application of botulinum toxin A (BT-A) has become a reliable lately. This study aimed to evaluate the correlation between the changes in masseter muscle thickness and clenching habits in bruxism patients treated with BT-A. Methods: Twenty-five patients, 23 females and 2 males, diagnosed with possible sleep bruxism were included in the study. The Fonseca Anamnestic Index was applied to the patients to determine their clenching habits and depression levels both before the treatment, and 6 months after it. The masseter muscle thickness was measured using ultrasonography before the treatment and 3 months and 6 months after the treatment. All the patients were injected with a total of 50 U of BT-A, 25 U to each masseter. Results: A statistically significant decrease in masseter muscle thickness was observed in the ultrasonography 3 and 6 months after the BT-A treatment. There was a statistically significant decrease in the Fonseca scores, in which the teeth clenching habits of the patients were evaluated 6 months after the treatment. Although there was a decrease in the depression levels of the patients 6 months after the treatment, this difference was not statistically significant. Conclusion: When the results of this study were evaluated, it was seen that the BT-A injections are an effective, safe, and side effect-free method in the treatment of bruxism and masseter hypertrophy.Öğe The Prevalence of Radix Paramolaris and Entomolaris in Mandibular Molar Teeth: A Retrospective Study(2022) Gökdeniz, Seyide Tuğçe; Önder, Merve; Öztürk, Hilal Peker; Samunahmetoğlu, Erçin; Eren, Hakan; Kurt, Mehmet HakanPurpose: This study aims to analyze the frequency of radix paramolaris (RP) and radix entomolaris (RE) in the mandibular ?rst\rand second molars using cone-beam computed tomography (CBCT).\rMaterials & Methods: The CBCT images of 400 patients at the ages of 14 to 66 were included in the study. On the included images,\rtwo maxillofacial radiologists simultaneously examined the presence of RP and RE by using axial CBCT cross-sections from the\rcrown down to apical.\rResults: The prevalence of at least one RE or RP was 9% (36/400). RP was found in 1.25% (n = 20) of the teeth. Of these, two cases\rwere bilateral, and 16 unilaterally occurred. RE was detected in 2.38% (n = 38) of the teeth, with 11 bilateral and 16 unilateral cases.\rThe prevalence of at least one RE or RP was 10.7% (16/149) for males and 8% (20/251) for females. No statistical sex-related and\rside-related difference (p > 0.05 ) was detected for the prevalence of RP and RE.\rConclusion: The study con?rms a 9% prevalence of at least one root variation (RP or RE) in permanent mandibular molars in a\rTurkish subpopulation. Clinicians need to be aware of such anatomical variations in the number of roots since they can complicate\rroot canal treatments and tooth extractionsÖğe Ultrasound examination of various dental materials and foreign bodies(2023) Deniz, Yeşim; Ak, Rüya Sessiz; Eren, HakanPurpose To provide information on the sonographic properties of different foreign bodies and dental materials to help with diagnosis. Materials & Methods The investigation contained 10 various dental materials and foreign bodies that were consisting of composite, glass ionomer cement, gutta percha, suture, wooden, stone, canal file, acrylic, alginate, and silicone impression material. The objects were embedded to chicken meat and imaged using ultrasonography (USG). Their visibility and posterior acoustic behaviors were evaluated by both hockey and linear transducers. The actual sizes of this objects and measured dimensions by transducers were compared. Results Only gutta percha could not be distinguished in chicken meat. No difference was observed between the measurements made with the hockey and linear transducers and the actual size. Conclusion USG is a useful method for detecting and measuring foreign bodies and dental materials in soft tissues.
