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Bibliografia degli scritti di Giorgio R. Cardona [con un 'elenco degli interventi in ricordo di G.R.C. apparsi nella stampa periodica']
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Erratum: Two-dimensional and three-dimensional cephalometry using cone beam computed tomography scans (Journal of Craniofacial Surgery (2015) (e311))
No full textLateral cephalometric radiograph produces a two-dimensional
image with several drawbacks. Cone beam computed tomography
(CBCT) allows obtaining a three-dimensional representation
of the craniofacial structures and seems to overcome the problems
of superimposition and magnification, providing more precision
than two-dimensional methods. The aim of the current study was
to test the intraobserver and interobserver reliability of linear and
angular measurements performed on two-dimensional conventional
cephalometric images and CBCT-generated cephalograms, and to
evaluate if there is a statistically significant difference between the
2 methods of measurements. The sample group consisted of 24
adolescents with a pretreatment digital lateral radiograph and a
corresponding CBCT image. A total of 16 cephalometric landmarks
were identified and 17 widely used measurements (9 angular and
8 linear)were recorded by 2 independent observers. Intraobserver and
interobserver reliability were assessed by calculating Pearson correlation
coefficient. Student t-test was used to compare the 2 methods.
The threshold for significance was set at P0.05.
Concerning the intraobserver and interobserver reliability, data
showed a statistically significant correlation between all two-dimensional
and three-dimensional measurements. The linear and angular
measurements of two-dimensional and three-dimensional cephalometry
were not statistically different. The results of the current study
showed the reliability of both conventional two-dimensional and
three-dimensional cephalometry. Linear and angular measurements
from CBCT were found also to be similar to conventional measurements.
Considering that conventional images deliver the lowest
radiation doses to patients, the use of CBCT for orthodontic purposes
should be limited
SORRISO, RIVALUTAZIONE DI SÉ, RECUPERO ALLA SOCIALITÀ: UNO STUDIO SPERIMENTALE IN MALATI MENTALI GRAVI
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Dentinogenesis imperfecta: a study using scanning electron microscopy and microanalysis.
No full text[Dentinogenesis imperfecta. Scanning electron microscopic study and microanalysis]. Dentinogenesi imperfetta. Studio al microscopio elettronico a scansione e microanalisi.
No full textAbstract
BACKGROUND: Dentinogenesis imperfecta (DI) is an inherited dentine defect which affects both the primary and secondary dentitions. Shields et al. in 1973 suggested a classification of DI within three types: type I, associated with osteogenesis imperfecta (OI), type II and type III. Although the varying clinical, radiographic and histological findings in DI have been described in detail, an available method for closer examination of the abnormal dentine matrix, electron microscopy, has seldom been used. Scanning and transmission electron microscopy studies can help to understand the pathogenesis of the different types of heritable dentine defects and the diagnosis and classification of these diseases. The aim of the present study was to evaluate a case of DI using scanning electron microscopy and microanalysis. METHODS: Dentine was obtained from tooth samples from a fourteen-year-old boy affected by DI and from third molars extracted for therapeutic reasons used as controls. Samples were observed with a scanning electron microscope, scanning electron micrographs were evaluated with an image analysis program and specimens were finally observed with a scanning electron microscope equipped for micro-analysis. RESULTS AND CONCLUSIONS: The results obtained showed that the total number of dentinal tubules was significantly reduced and the presence of a dentine mineralization defect in the patient affected by DI, in comparison to the controls
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Are intraoral radiographs reliable in determining peri-implant marginal bone level changes? The correlation between open surgical measurements and peri-apical radiographs
No full textThis study was performed to evaluate the reliability of peri-apical
radiographs in determining peri-implant marginal bone level changes. The
STROBE guidelines were followed. Marginal bone levels were measured at the
time of implant insertion using a straight periodontal probe and using peri-apical
radiographs. These intraoperative and radiographic measurements were repeated at
the time of second surgery. All radiographs were analysed by two examiners blinded
to the intraoperative measurements. To standardize the radiographic images, the
long-cone parallel technique and a film-holding system were used. Intra-observer
agreement and inter-observer variability were assessed using the intra-class
correlation coefficient (ICC). Descriptive statistics, the t-test, and the Pearson
correlation coefficient were also used. A total of 268 implants were inserted in 142
patients. Inter-observer agreement was 0.950; intra-observer variability was 0.980
and 0.973. The mean difference between the radiographic and intraoperative
measurements was 0.50 1.55 mm (range 0–8 mm); the difference was
statistically significant (P = 0.000). A significant linear correlation was found
between the marginal bone level changes evaluated intraoperatively andradiographically (P < 0.005). Radiographic analysis significantly overestimated
the level of peri-implant marginal bone compared to intraoperative measurements,
but peri-apical radiographs are reliable in determining the bone level changes at
different follow-ups
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