248 research outputs found
Ectopic third molar in the mandibular sigmoid notch: report of a case and literature review
Purpose: To evaluate the etiopathogenesis, clinical features and surgical approaches for removal of ectopic third
molars in the mandible.
Methods: We report a case of an impacted mandibular third molar dislocated on mandibular sigmoid notch. 20
cases of ectopic mandibular third molars reported in the English-language literature, identified from Pubmed and
Medline databases are also reviewed.
Results: Among the 20 article reported in the presented study, ectopic third molars were generally located in the
condylar region. The common symptoms of the clinical examination were pain, trismus, swelling, temporomandibular joint syndroms or no symptoms.
Conclusions: Ectopic third molar may be asymptomatic initially with clinical manifestations, later on as adjacent
structures are affected. The surgical approach must be carefully planned for the aim of choosing the more conservative technique that produces the minimum trauma to patients
Comparison of the effects of rapid maxillary expansion and surgically assisted rapid maxillary expansion in the sagittal, vertical and transverse planes
Objective: The aim of this study was to evaluate and compare the effects of rapid maxillary expansion (RME) and surgically assisted RME (SARME) in the sagittal, vertical, and transverse planes. Study design: Orthodontic records of 28 patients were selected retrospectively and divided into two treatment groups. Group 1 comprised 14 patients (4 boys, 10 girls, mean age 14.2 ± 0.74 years) who had been treated with RME. Group 2 comprised 14 patients (4 boys, 10 girls, mean age 19.6 ± 2.73 years) who had been treated with SARME. Measurements were performed on lateral and posteroanterior cephalograms and dental casts obtained before (T0) and after (T1) expansion. Results: Statistically significant differences were found in soft tissue convexity angle, anterior face height, and upper nasal width in group 1, and in U1-NA length and posterior face height measurements in group 2 (P<.05). In both groups significant increases were found in interpremolar, intermolar, maxillary, and lower nasal widths and in anterior lower face height (P<.01). Statistically signifificant intergroup differences were found in the ANB angle (P<.05) and maxillary intercanine (P<.01) measurements. Conclusion: With both RME and SARME, successful expansion of maxillary dentoalveolar structures and nasal cavity and palatal widening were achieved. Sagittal plane effects of SARME were similar to those of RME on dental skeletal and airway measurements. © Medicina Oral
TEKNOLOJİ GELİŞTİRME BÖLGESİ YÖNETİCİ ŞİRKETLERİNİN YÖNETİM ETKİNLİĞİNİN VERİ ZARFLAMA ANALİZİ İLE DEĞERLENDİRİLMESİ
Bu çalışmada 4691 sayılı Teknoloji Geliştirme Bölgeleri (TGB) Kanunu kapsamında bölgenin yönetimi ve işletmesinden sorumlu şirketin yönetim etkinliğinin değerlendirilmesi amaçlanmaktadır. Bu doğrultuda 2014 yılı verileri ile 39 teknopark yönetici şirketinin yönetim etkinliği temel Veri Zarflama Analizi (VZA) ile değerlendirilmiştir. Etkinlik ölçümünde üç girdi (Kapasite geliştirme faaliyet sayısı, Toplam işbirliği sayısı, Anahtar personel sayısı) ve dört çıktı (Akademik spin-off sayısı, Firma sayısı, Yabancı firma sayısı, Toplam istihdam) kullanılmıştır. Çalışmanın sonucunda CCR modeline göre 10 teknopark teknik etkin, 23 teknopark saf teknik etkin ve 12 teknopark ölçek etkin bulunmuştur.
Anahtar Kelimeler: Teknoloji Geliştirme Bölgesi, Teknopark, Etkinlik, Veri Zarflama Analizi.
JEL Sınıflandırma Kodları: O32, C61, D61
The Double Gaussian Distribution of Inhomogeneous Barrier Heights in Al/GaN/p-GaAs (MIS) Schottky Diodes in Wide Temperature Range
The current-voltage (I-V) characteristics of metal-insulator-semiconductor (Al/GaN/p-GaAs) Schottky barrier diodes (SBDs) were investigated over a wide temperature range of 80-380 K. By using the thermionic emission (TE) theory, the zero bias barrier height Φ B0 calculated from I-V characteristics was found to increase with increasing temperature as the ideality factor n decreases with increasing temperature, and especially the activation energy plot is nonlinear at low temperatures. The observed variation in the Φ B0 and n is attributed to the spatial barrier inhomogeneities in SBD by assuming a Gaussian distribution (GD) of barrier heights (BHs). The experimental I-V-T characteristics of the SBDs have shown a double Gaussian distribution having mean barrier heightsΦ B of 0.854 eV and 0.395 eV and standard deviations σ s for 0.142 V and 0.059 V, respectively. The modified ln(I o /T 2 )-q 2 σ 2 o /2(kT) 2 vs q/kT plot gives Φ B0 and Richardson constant A * as 0.858 eV and 0.364 eV, and 78.5 and 128 A/cm 2 K 2 , respectively, without using the temperature coefficient of the barrier height. Hence, the results have shown that the I-V-T characteristics of the Al/GaN/p-GaAs SBDs can be successfully explained on the basis of TE mechanism with a double Gaussian distribution of the barrier heights
Supernumerary, ectopic tooth in the maxillary antrum presenting with recurrent haemoptysis
<p>Abstract</p> <p>Background</p> <p>Ectopic eruption of teeth in non-dental sites is a rare phenomenon and can present in a variety of ways such as chronic or recurrent sinusitis, sepsis, nasolacrimal duct obstruction, headaches, ostiomeatal complex disease and facial numbness. However, presentation of such patients with recurrent haemoptysis has not been described in the literature so far. We have described a case of an ectopic, supernumerary molar tooth in the maxillary antrum in a patient who initially presented with haemoptysis.</p> <p>Case presentation</p> <p>A 45-year-old male presented with a 2-month history of episodic haemoptysis. A pedunculated growth from the inferior nasal turbinate was seen with fibre-optic visualization. Although the patient was empirically started on antibiotic and anti-allergic therapy, there was no improvement after a few weeks and the patient had recurrent episodes of haemoptysis. Fibre-optic visualization was repeated showing bilateral osteomeatal erythema. Computed tomography scan of the paranasal sinuses demonstrated complete opacification of the left maxillary antrum along with a focal area of density comparable to bone. An ectopic, supernumerary molar tooth was found in the left maxillary antrum on endoscopic examination and subsequently removed. In addition, copious purulent discharge was seen. Post-operatively, the patient was treated with a 10-day course of oral amoxicillin-clavulanate. On follow-up, he reported resolution of symptoms.</p> <p>Conclusion</p> <p>Recurrent haemoptysis has not been described as a presentation for a supernumerary, ectopic tooth in literature before. We recommend that in patients with sinusitis-type of opacification of maxillary antrum and whose condition is refractory to conventional medical treatment, consideration should be given to the investigation of possible underlying anomalies as the cause of such symptoms. Presence of foreign bodies and ectopic teeth in paranasal sinuses can be reliably excluded with the use of appropriate radiological imaging and endoscopic examination.</p
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