Search results for "Caliper"
showing 8 items of 28 documents
Two-second standardization of the Harpenden Caliper.
1981
Comparative in vitro study of two methods for gingival biotype assessment
2018
Background The gingival thickness seems to have an important role in different dental treatments. There are different methods of quantifying this thickness, but it is not known which of them can be the most effective. The objective to assess the accuracy of two different methods for gingival thickness measurement: the transgingival needle probing (TGNP) and the tension-free caliper (TFC) in an in vitro model, by comparing them with direct physical measurements (reference standard). Material and methods Gingival thickness (GT) was evaluated in 27 female pigs with four implant sites 1, 2 and 3mm from the gingival margin with three different methods: 1) transgingival needle probing 2) tension-…
Direkte Dickenmessung an Muskelstreifenpräparaten und Gewebsschnitten
1967
An apparatus for direct measurement of the thickness of tissue slices and muscle strips is described. Micrometer callipers are used, the proper adjustment of which is indicated by the sudden scale deflection of an ohmmeter. In comparison with the method of calculation based on a measurement of the area of the slice, this technique is time-saving and the results are more accurate and reproducible.
Ex vivo measurement reliability using two different cbct scanners for orthodontic purposes
2012
Background There are many cone beam computed tomography (CBCT) scanners available on the market: detector technology, algorithm precision, and scanner settings influence image quality. The aim of this study was to compare the accuracy of linear measurements made on images of the same sample obtained using two different CBCT scanners. Methods Twenty-eight linear measurements between orthodontic anatomical landmarks that were marked with gutta-percha points on a fresh sacrificed lamb head were taken three times. The head was scanned with two CBCT scanners using different scanning parameters. Digital Imaging and Communications in Medicine (DICOM) images were reconstructed and the same measurem…
Using the Breeder genetic algorithm to optimize a multiple regression analysis model used in prediction of the mesiodistal width of unerupted teeth
2014
For the prediction of the unerupted canine and premolars mesiodistal size, have been proposed different variants of multiple linear regression equations (MLRE). These are based on the amount of the upper and lower permanent incisors with a tooth of the lateral support. Aim of present study was to develop a method for optimization of MLRE, using a genetic algorithm for determining a set of coefficients that minimizes the prediction error for the sum of permanent premolars and canines dimensions from a group of young people in an area Romania's central city represented by Sibiu. To test the proposed method, we used a multiple linear regression equation derived from the estimation method propo…
Does taking additional Maths classes in high school affect academic outcomes?
2023
Several studies in the mathematical education literature show the effect of students’ high school skills in maths on their success at higher levels of education and work. In particular, the importance of maths course taking in US high schools is highlighted to be important for college enrolment and completion. The choice of taking additional maths courses or, as in Italy, of choosing a high-school curriculum with more maths, is not random: it depends on several substantial factors such as gender and socio-economic status. This selection bias implies that the differences in the academic outcomes might be traceable not only to mathematics ability and knowledge. In this paper, the aim is to es…
Spiral-CT und 3 D-Rekonstruktion des Tracheobronchialbaumes zur Auswahl geeigneter Doppellumentuben vor Einzellungenbeatmung
1997
Purpose To assess the potential of 3-D spiral CT in the selection of adequate double-lumen tubes (DLT) for one-lung-ventilation. Materials and methods 3-D spiral CT of eight different DLTs was performed with standardized acquisition parameters: section thickness 4 mm, table speed 6 mm/s, increment 3 mm and standardised thresholds, window settings and magnification zoom. The accuracy was confirmed by measuring 3-D objects on screen and original DLTs by vernier caliper. 3-D spiral CT was performed in 20 patients preoperatively with slice thickness 4-8 mm, pitch 1-1.5, increment 4-8 mm. To select the adequate DLT size the 3-D reconstructions of the patient's tracheobronchial tree and of the DL…
Accuracy of automatic airway morphometry in computed tomography-correlation of radiological-pathological findings.
2010
Abstract Objectives Airway morphology shows characteristic changes in different pathologies. This study assesses the accuracy of a current automatic airway assessment technique by correlating CT images of porcine airways to histological slices of the same localization. Materials and methods Four isolated and ventilated porcine lungs were frozen in a liquid nitrogen bath and examined with a CT scanner (MDCT). This technique both preserved normal radiomorphological appearance and made it possible to slice the specimens for histological examination for subsequent correlation. The parameters wall thickness (WT), wall percentage (WP), and total diameter (TD) were assessed by computer-aided measu…