52 research outputs found
Thermal decomposition kinetics of the antiparkinson drug “entacapone” under isothermal and non-isothermal conditions
© 2017 Akadémiai Kiadó, Budapest, Hungary The thermal decomposition kinetics of entacapone (ENT) have been investigated via thermogravimetric analysis under non-isothermal and isothermal conditions which provide useful stability information for their processing in the pharmaceutical industry and also for predicting shelf life and suitable storage conditions. The determination of the kinetic parameters for the decomposition process under non-isothermal conditions in a nitrogen atmosphere at four heating rates (5, 10, 15, and 20 °C min −1 ) was performed. Kinetic parameters of the decomposition process for ENT were calculated through Friedman, Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose, and Li–Tang methods. This work demonstrates that the activation energies calculated from the decomposition reactions by different methods are consistent with each other. Moreover, the thermodynamic functions of the decomposition reaction were also calculated
Evaluation of the Accessory Mental Foramen in a Pediatric Population Using Cone-Beam Computed Tomography
The aim of the present study was to clarib, the occurrence, diameter, and location of the accessory mental foramen (AMP) using cone-beam computed tomography (CBCT) images from a sample of Turkish children. Study design: This retrospective was carried out using a total of 275 CBCT images from child and adolescent patients were randomly selectedfrom existing records in the Department of Oral and Maxillofacial Radiology at the University of Erciyes, Kayseri, Turkey. The mental foramen (MF) and AMF were assessed on axial, sagittal, and coronal CBCT slices. Results: The mean age was 10.51 3.32 years, consisting of 139 males (mean age 10.64 3.42) and 126 females (mean age 10.38 3.18). Twenty-one Allff's were observed in 18 of 275 patients (6.5%, 10 boys and eight girls). There was no significant difference in gender in relation to the prevalence 0f AMP (p = 0.65). The mean area of the 21 AMFs and the ME on the side with the Alvh7 were 0.7 mm2 (SD 0.5) and 3.8 mm2 (SD 2.2), respectively. Conclusion: It is important to stress that detecting the AMN using CBCT with 3D reconstructions may reduce the risk of paralysis, hemorrhage, and postoperative pain in this region. Our study presents the first report assessing the occurrence, diameter, and location of the AMP in the pediatric population using CBCT images. In this respect, not surprisingly, the mean size of the AMP of our population is smaller than other reports in the literature that involve adult populations
Enrichment and determination of Ni2+ ions in water samples with a diamino-4-(4-nitro-phenylazo)-1H-pyrazole (PDANP) by using FAAS
WOS: 000277631000008Nickel, as a heavy metal, is toxic for many living species. Thus, the determination of trace amounts of nickel in environmental samples is of great importance. In the present study, new, sensitive, simple and validated solid phase extraction method is developed for the determination of nickel. In recent study nickel was preconcentrated as diamino-4-(4-nitro-phenylazo)- 1H-pyrazole (PDANP) chelates (Ni-PDANP) from sample solutions using a column containing Amberlite XAD-7 and determined by flame atomic absorption spectrometry (FAAS). The optimum experimental parameters such as pH of the medium, sample flow rate, eluent and effect of matrix ions on the method efficiency were investigated. The optimum pH value for quantitative sorption of Ni-PDANP was found between 6.0 and 8.0. Elution process was performed by using 6 mL of 2 mol L-1 HCl. The sorption capacity of resin was determined to be 7.2 mg g(-1) for Ni. The preconcentration factor was 125. In optimized conditions. A relative standard deviation and detection limit were found to be 2.8% and 0.44 mu g L-1 respectively. The method was successfully applied to determine the trace amounts of nickel in tap water and mineral waters, and suitable recoveries were obtained (100.0-103.5%). (C) 2010 Elsevier B.V. All rights reserved
Tetrafid mandibular condyle: a unique case report and review of the literature
Morphological changes such as bifid and trifid mandibular condyle are rare entities. The aim of the present report is to describe a unique morphological variation of the mandibular condyle which has four separate condylar heads (tetrafid mandibular condyle) and to discuss clinical and radiological differential diagnosis of tetrafid mandibular condyle with advanced imaging techniques. Dentomaxillofacial Radiology (2011) 40, 524-530. doi: 10.1259/dmfr/6208266
An unusual case of multilocular Stafne bone cavity
Stafne bone defects (SBDs) are asymptomatic lingual bone depressions of the lower jaw that are frequently caused by soft-tissue inclusion. The common variant of SBD exists at the third molar region of the mandible below the inferior dental canal is an and ovoid-shaped homogeneous well-defined radiolucency. In this report, an unusual occurrence of SBD with multilocular appearance is presented. Asymptomatic lingual bone defects may represent various radiographic features. Detailed radiographic evaluation with CT scans should be performed to differentiate SBDs from other pathologies. Dentomaxillofacial Radiology (2012) 41, 75-78. doi:10.1259/dmfr/3473196
Clinical and radiographic evaluation of double teeth in primary dentition and associated anomalies in the permanent successors
Objective: Understanding potential problems associated with primary double teeth (PDT) are important to provide prophylactic measures, thereby preventing or minimizing possible complications. The purposes of this study were to investigate the prevalence of PDT in a group of Turkish children and to compare the distribution of the different types of double primary teeth and their relationship to permanent successors. Materials and Methods: A total of 17,268 children underwent a clinical examination to determine the presence of PDT. One hundred fifty-two PDT of 128 children were included in this study. All the 128 children with PDT underwent a clinical examination and had photographs taken at the time of the examination. The children underwent a further periapical or panoramic radiographic examination to determine the status of the underlying permanent successors. The PDT was classified according to Aguilo's classification. Results: The prevalence of PDT was 0.74%, with no significant statistical difference between the sexes. PDT was most frequently observed between the mandibular lateral incisors and canines. Of the 152 PDT, 10.7% were Type I, 15.3% were Type II, 26.1% were Type III, and 47.9% were Type IV. Dental anomalies on the succedaneous permanent teeth were diagnosed in 69.4% of the children with affected primary dentition. Aplasia of the permanent lateral incisor was observed most frequently in association with Type I (52.7%) PDT. Caries involvement was observed most frequently in Type III (56.2%) PDT. Conclusion: The findings of this study have clinical relevance for the diagnosis of children with PDT. Early clinical and radiographic identification of PDT can help the clinician to evaluate the number and condition of permanent successors and draw up a proper treatment plan
Maxillary Dental Anomalies in Patients with Cleft Lip and Palate: A Cone Beam Computed Tomography Study
Objective: To compare the frequency of maxillary dental anomalies in patients affected by unilateral (UCLP) and bilateral (BCLP) cleft lip with palate and to determine whether statistical differences were present or not between cleft and normal sides in UCLP group by using cone beam computed tomography (CBCT). In addition, the frequency of those dental anomalies was compared with previous studies presenting the same population without cleft Study Design: Fifty non-syndromic patients affected by UCLP (28 patients) and BCLP (22 patients) were selected for analysis of dental anomalies by means of CBCT. The frequency of maxillary dental anomalies including tooth agenesis, microdontia of lateral incisor, ectopic eruption and impaction of canine and supernumerary tooth were examined. Pearson chi-square and Fisher's exact tests were performed for statistical comparisons. Results: All patients affected by UCLP and BCLP were found to have at least one maxillary dental anomaly. The most frequently observed dental anomaly was tooth agenesis (92.5% and 86.4%, respectively) in UCLP and BCLP groups. Tooth agenesis and canine impaction were observed more commonly in the cleft side (75.0% and 35.7%, respectively) than in the normal side (57.1% and 14.3%, respectively) in UCLP group (p>0.05). All dental anomalies were found to be higher in both cleft groups than in general populations not affected by cleft. Conclusion: Since patients affected by UCLP and BCLP had at least one dental anomaly and higher dental anomaly frequency as compared to patients without cleft, those patients should be examined carefully prior to orthodontic treatment
Effects of cleft lip and palate on the development of permanent upper central incisors: a cone-beam computed tomography study
WOS: 000362967200015PubMed: 25548146Objective: The aim of this study was to evaluate 1. the differences among the cleft sides of unilateral cleft lip and palate (UCLP) patients, non-cleft sides of the same UCLP patients and well matched control patients in the root development and position of permanent upper central incisors and 2. possible gender differences. Materials and methods: The study sample consisted of 40 patient (20 males and 20 females; mean age: 14.84 +/- 3.2 years) with non-syndromic UCLP patients, and 40 control patients (20 males and 20 females; mean age: 13.38 +/- 1.6 years). Cone-beam computed tomography (CBCT) images were taken off from all patients. All tomographs were obtained in supine position by using CBCT (NewTom 5G, QR, Verona, Italy). Results: Significant smaller root volume of central incisor was observed on the cleft side than on the non-cleft side of UCLP patients (P 0.05). There were no statistically significant gender differences in any linear, angular, or volumetric measurements (P > 0.05). Only the root volume of the cleft side was smaller in females than in males (P < 0.05). Conclusions: In general, root volumes of central incisors on the cleft side were 12.15 per cent smaller than non-cleft side. Root development of the central incisor was much more influenced by the cleft in females than in males
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