Aim: The presented study aim was to find out whether a cephalogram and a scan generated from 3D CBCT of one and the same patient are different or identical. Material and method: The retrospective study included 41 patients with complete orthodontic documentation with a cephalogram and a CBCT taken prior to treatment. The CBCT can be synthesized into cephalogram in orthogonal and perspective projections with Dolphin Imaging 11.95 Premium (Dolphin Imaging and Management Solutions, Chatsworth, CA, USA). Both scans were taken within one month. The same software was used for cephalometric analysis of cephalograms and CBCT generated scans. 7 angular and 3 linear parameters (including dental and skeletal parameters in sagittal and vertical planes) were selected for the study. Results: Statistically significant differences between scans made with three different techniques were found in the following parameters: angular dimension of SNB, and linear parameters WITS, U1-APo, L1-APo. Conclusion: The individual techniques differ to some extent. However, majority of differences in mean values was < 0.6° and < 0.7 mm which suggests that their significance is not important from clinical viewpoint. The techniques are comparable.
INTRODUCTION: The process of fabricating physical medical skull models requires many steps, each of which is a potential source of geometric error. The aim of this study was to demonstrate inaccuracies and differences caused by DICOM to STL conversion in additively manufactured medical skull models. MATERIAL AND METHODS: Three different institutes were requested to perform an automatic reconstruction from an identical DICOM data set of a patients undergoing tumour surgery into an STL file format using their software of preference. The acquired digitized STL data sets were assessed and compared and subsequently used to fabricate physical medical skull models. The three fabricated skull models were then scanned, and differences in the model geometries were assessed using established CAD inspection software methods. RESULTS: A large variation was noted in size and anatomical geometries of the three physical skull models fabricated from an identical (or "a single") DICOM data set. CONCLUSIONS: A medical skull model of the same individual can vary markedly depending on the DICOM to STL conversion software and the technical parameters used. Clinicians should be aware of this inaccuracy in certain applications.
- MeSH
- algoritmy MeSH
- design s pomocí počítače statistika a číselné údaje MeSH
- kefalometrie statistika a číselné údaje MeSH
- lebka anatomie a histologie MeSH
- lidé MeSH
- mandibula anatomie a histologie MeSH
- modely anatomické * MeSH
- nosní dutina anatomie a histologie MeSH
- orbita anatomie a histologie MeSH
- počítačová tomografie s kuželovým svazkem statistika a číselné údaje MeSH
- počítačové zpracování obrazu statistika a číselné údaje MeSH
- povrchové vlastnosti MeSH
- radiologické informační systémy statistika a číselné údaje MeSH
- sinus maxillaris anatomie a histologie MeSH
- software MeSH
- zobrazování trojrozměrné statistika a číselné údaje MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
INTRODUCTION: The aim of this study was to determine the reproducibility and accuracy of linear measurements on 2 types of dental models derived from cone-beam computed tomography (CBCT) scans: CBCT images, and Anatomodels (InVivoDental, San Jose, Calif); these were compared with digital models generated from dental impressions (Digimodels; Orthoproof, Nieuwegein, The Netherlands). The Digimodels were used as the reference standard. METHODS: The 3 types of digital models were made from 10 subjects. Four examiners repeated 37 linear tooth and arch measurements 10 times. Paired t tests and the intraclass correlation coefficient were performed to determine the reproducibility and accuracy of the measurements. RESULTS: The CBCT images showed significantly smaller intraclass correlation coefficient values and larger duplicate measurement errors compared with the corresponding values for Digimodels and Anatomodels. The average difference between measurements on CBCT images and Digimodels ranged from -0.4 to 1.65 mm, with limits of agreement values up to 1.3 mm for crown-width measurements. The average difference between Anatomodels and Digimodels ranged from -0.42 to 0.84 mm with limits of agreement values up to 1.65 mm. CONCLUSIONS: Statistically significant differences between measurements on Digimodels and Anatomodels, and between Digimodels and CBCT images, were found. Although the mean differences might be clinically acceptable, the random errors were relatively large compared with corresponding measurements reported in the literature for both Anatomodels and CBCT images, and might be clinically important. Therefore, with the CBCT settings used in this study, measurements made directly on CBCT images and Anatomodels are not as accurate as measurements on Digimodels.
- MeSH
- kefalometrie statistika a číselné údaje MeSH
- lidé MeSH
- počítačová tomografie s kuželovým svazkem statistika a číselné údaje MeSH
- počítačové zpracování obrazu statistika a číselné údaje MeSH
- povrchové vlastnosti MeSH
- reprodukovatelnost výsledků MeSH
- software MeSH
- zobrazování trojrozměrné statistika a číselné údaje MeSH
- zubní korunka (anatomie) anatomie a histologie MeSH
- zubní modely * MeSH
- zubní oblouk anatomie a histologie MeSH
- zubní technika otisková statistika a číselné údaje MeSH
- zuby anatomie a histologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Cíl: Cílem studie bylo posoudit, zda kefalometrická analýza měřená na kefalometrických snímcích získaných vygenerováním z dat cone-beam CTje shodná s analýzou měřenou na standardních dálkových snímcích. Při zhotovení cone-beam CT u složitějších ortodontických případů by poté odpadla potřeba zhotovovat navíc dálkový snímek Ibi a mandibuly a ortopantomogram. Materiál a metodika: Do soubonj bylo zařazeno 27 poacientů, jejichž dokumentace zahrnovala digitální telerentgenový snímek a vyšetření cone-beam CT. U každého pacienta v souboru byla provedena kefalometrická analýza na digitálním snímku a na 2 snímcích generovaných z dat cone-beam CT. K vygenerování kefalometrických snímků byly využity dva renderovací algoritmy, Ray Sum a maximum intensity projection (MIP). Bylo hodnoceno 11 úhlů a 4 lineální vzdálenosti. Závěr: Nebyly nalezeny signifikantní rozdíly mezi 3 metodami zobrazení v žádném z porovnávaných parametrů. Generované kefalometrické snímky z cone-beam CT, potažmo na nich naměřené rozměry a úhly jsou klinicky použitelné pro kefalometrickou analýzu.
Aims: The aim of our study was to evaluate whether cephalometric analysis using cephalograms generated from cone-beam CTdata is congruent with analysis meaiired on conventional cephalograms. With cone-beam CTused in more complex orthodontic cases, the additional cephalograms and panoramic dental X-ray pictures would not be necessary. Material and methods: The sample included 27 patients whose records contained a digital cephalogram, and cone-beam CT examination. In each patient, cephalometric analysis of the digital radiograph was made as well as of)f2 pictures generated from cone-beam CT data. To generate cephalograms two rendering algorithms were used, Ray Sum and maximum intensity projection (MIP). 11 angles and 4 linear distances were assessed. Conclusion: Between the 3 imaging techniques no significant differences were found in any of the parameters monitored. Cephalograms generated from cone-beam CT data (i.e. the dimensions and angles rendered), are clinically applicable for cephalometric analysis.
- Klíčová slova
- kefalometrická analýza,
- MeSH
- analýza rozptylu MeSH
- artefakty MeSH
- brada anatomie a histologie radiografie MeSH
- čelisti anatomie a histologie radiografie MeSH
- digitální zubní radiografie metody MeSH
- kefalometrie * metody statistika a číselné údaje MeSH
- lidé MeSH
- multivariační analýza MeSH
- nosní kost anatomie a histologie radiografie MeSH
- odchylka pozorovatele MeSH
- počítačová tomografie s kuželovým svazkem * metody statistika a číselné údaje MeSH
- počítačové zpracování obrazu statistika a číselné údaje MeSH
- reprodukovatelnost výsledků MeSH
- sella turcica anatomie a histologie radiografie MeSH
- zobrazování trojrozměrné MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- srovnávací studie MeSH
