QZ - Quintessenz Zahntechnik, 3/2021
BuchbesprechungPages 334-335, Language: GermanWesemann, Christian
Quintessence International, 8/2017
DOI: 10.3290/j.qi.a38676, PubMed ID (PMID): 28740969Pages 667-676, Language: EnglishNowak, Roxana / Wesemann, Christian / Robben, Jan / Muallah, Jonas / Bumann, Axel
Objective: The purpose of this study was to evaluate the accuracy of full-arch scans using 11 different cast scanners.
Method and Materials: Dental arch length (AL), intermolar width (IMW), and intercanine width (ICW) of the reference plaster casts were measured using a coordinate measuring machine (Zeiss O-Inspect 422). The master cast was subsequently scanned 37 times using 11 desktop scanners (3Shape R500, 3Shape R700, 3Shape R1000, 3Shape R2000, Medianetx grande, Medianetx colori, DentaCore CS ULTRA, Dentaurum OrthoX, Maestro 3D, Imetric IScan D104i, GC Aadva Lab Scan). Using the software Convince Premium 2012 (3Shape), AL, IMW, and ICW were measured on the digital models and compared to the reference plaster cast.
Results: The accuracy of the cast scanners differed significantly. The most accurate measurements were given by the cast scanners 3Shape R700 (ICW: 7.4 ± 5.9 µm) and Imetric IScan D104i (ICW: 9.1 ± 4.9 µm). The cast scanners 3Shape R1000 (ICW: 11.2 ± 3.4 µm) and GC Aadva Lab Scan (ICW: 13.8 ± 8.1 µm) yielded comparable measurements. DentaCore (ICW: 26.6 ± 7.5 µm) and Dentaurum OrthoX (ICW: 31.1 ± 24 µm) were significantly less accurate.
Conclusion: Almost all scanners demonstrated a level of accuracy so high that further improvement would not provide additional benefit for use in orthodontics. Advancement of the scanners should focus primarily on reducing time and cost. For prosthodontic use, the scanners with the highest accuracy are recommended.
Keywords: accuracy, CAD/CAM, desktop scanner, digital model, full-arch scan, plaster cast
International Journal of Computerized Dentistry, 4/2017
PubMed ID (PMID): 29292411Pages 363-375, Language: English, GermanRobben, Jan / Muallah, Jonas / Wesemann, Christian / Nowak, Roxana / Mah, James / Pospiech, Peter / Bumann, Axel
Kiefermodelle können mit Modellscannern, intraoralen Scannern und mittlerweile auch digitalen Volumentomographie (DVT)-Geräten digitalisiert werden. Das Ziel dieser Studie war es, die Genauigkeit von fünf verschiedenen DVT-Geräten bezüglich der Digitalisierung von Gipsmodellen zu untersuchen. Ein als Patient dienendes Studienmodell wurde mittels Doppelmischtechnik abgeformt und die Abformung mit Gips ausgegossen. Am resultierenden Gipsmodell wurden die Masterwerte für die Zahnbogenlänge, die Intermolarenweite und die Intercaninenweite mit einem Koordinatenmessgerät (Zeiss O-Inspect 422) gemessen. Anschließend wurde das Patientenmodell mit fünf DVT-Geräten bei acht Scan-Modi (CS 9300, CS 9300 Select, CS 8100 3D [Carestream]; Promax 3D MidTM [Planmeca] und Whitefox® [Acteon]) gescannt. Pro DVT-Gerät und Modus wurden 37 Scans angefertigt. Die resultierenden DICOM-Daten wurden als Stereolithografie-Daten exportiert und mit einer speziellen Messsoftware (Convince™ Premium 2012 [3Shape]) linear vermessen. Alle Messungen wurden mit den Masterwerten des Patientenmodells verglichen. Die Genauigkeitsmessungen ergaben signifikante Unterschiede zwischen den DVT-Geräten. Die höchsten Genauigkeiten zeigten das Whitefox® (IMW: MW ± SD: 5,5 ± 5,7 µm) und das CS 9300-Gerät (IMW: MW ± SD: -15 ± 7,4 µm). Vergleichbare Werte konnten auch bei geringerer Genauigkeit mit den CS 8100 3D (IMW: MW ± SD: -81,2 ± 7,4 µm) und CS 9300 Select (IMW: MW ± SD: -82,2 ± 6,6 µm) erzielt werden. Das Promax 3D MidTM-Gerät (IMW: MW ± SD: -126,1 ± 4,8 µm) erreichte die schlechtesten Werte. Einige DVT-Geräte eignen sich zur Digitalisierung von Gipsmodellen und weisen klinisch eine sehr gute Genauigkeit auf, sodass Praxen, die mit DVT-Geräten ausgestattet sind, Gipsmodelle digitalisieren könnten, ohne zusätzliche Geräte zu benötigen.
Keywords: DVT-Geräte, indirekte Digitalisierung, Gipsmodell, CAD/CAM, Genauigkeit, Stereolithografie
International Journal of Computerized Dentistry, 2/2017
PubMed ID (PMID): 28630956Pages 151-164, Language: English, GermanMuallah, Jonas / Wesemann, Christian / Nowak, Roxana / Robben, Jan / Mah, James / Pospiech, Peter / Bumann, Axel
The aim of this study was to compare the accuracy of six intraoral scanners as regards clinically relevant distances using a new method of evaluation. An additional objective was to compare intraoral scanners with the indirect digitization of model scanners. A resin master model was created by 3D printing and drilled in five places to reflect the following distances: intermolar width (IMW), intercanine width (ICW), and arch length (AL). To determine a gold standard, the distances were measured with a coordinate measuring instrument (Zeiss O-Inspect 422). The master model was scanned 37 times with the following intraoral scanners: Apollo DI (Sirona), CS 3500 (Carestream Dental), iTero (Cadent), PlanScan (Planmeca), Trios (3Shape), and True Definition (3M Espe), and indirectly digitized with the OrthoX Scan (Dentaurum). The digital models were then measured, and deviations from the gold standard calculated. Significant differences were found between the devices. Among the intraoral scanners, Trios and iTero showed the most accurate results, although CS 3500, True Definition, and Apollo DI achieved comparable results. PlanScan demonstrated the highest deviations from the gold standard, and presented a high standard deviation (SD). Direct digitization revealed comparable (and, in fact, slightly higher) accuracy than indirect digitization. Both indirect digitization and most of the intraoral scanners were therefore demonstrated to be suitable for use in the orthodontic office, with the exception of PlanScan, which did not meet the demands of individual orthodontic treatment.
Keywords: intraoral scanner, indirect digitization, full-arch scan, digital impression, CAD/CAM, accuracy
QZ - Quintessenz Zahntechnik, 10/2017
SciencePages 1262-1272, Language: GermanWesemann, Christian / Muallah, Jonas / Nowak, Roxana / Robben, Jan / Bumann, Axel
Ein Überblick direkter und indirekter Verfahren für die KieferorthopädieFür die Digitalisierung der Patientensituation stehen unterschiedliche direkte und indirekte Verfahren zur Verfügung. In dieser Studie wurde die Genauigkeit von 5 Intraoralscannern, 11 Modellscannern und 4 DVT-Geräten untersucht und mit der Genauigkeit von Modellen, die mittels Stereolithografie-Drucker erstellt wurden, verglichen.
Keywords: Intraoralscanner, Modellscanner, DVT, Digitalisierung, Genauigkeit
Quintessence International, 1/2017
DOI: 10.3290/j.qi.a37130, PubMed ID (PMID): 27834416Pages 41-50, Language: EnglishWesemann, Christian / Muallah, Jonas / Mah, James / Bumann, Axel
Objective: The primary objective of this study was to compare the accuracy and time efficiency of an indirect and direct digitalization workflow with that of a three-dimensional (3D) printer in order to identify the most suitable method for orthodontic use.
Method and Materials: A master model was measured with a coordinate measuring instrument. The distances measured were the intercanine width, the intermolar width, and the dental arch length. Sixty-four scans were taken with each of the desktop scanners R900 and R700 (3Shape), the intraoral scanner TRIOS Color Pod (3Shape), and the Promax 3D Mid cone beam computed tomography (CBCT) unit (Planmeca). All scans were measured with measuring software. One scan was selected and printed 37 times on the D35 stereolithographic 3D printer (Innovation MediTech). The printed models were measured again using the coordinate measuring instrument.
Results: The most accurate results were obtained by the R900. The R700 and the TRIOS intraoral scanner showed comparable results. CBCT-3D-rendering with the Promax 3D Mid CBCT unit revealed significantly higher accuracy with regard to dental casts than dental impressions. 3D printing offered a significantly higher level of deviation than digitalization with desktop scanners or an intraoral scanner. The chairside time required for digital impressions was 27% longer than for conventional impressions.
Conclusion: Conventional impressions, model casting, and optional digitization with desktop scanners remains the recommended workflow process. For orthodontic demands, intraoral scanners are a useful alternative for full-arch scans. For prosthodontic use, the scanning scope should be less than one quadrant and three additional teeth.
Keywords: 3D printed models, accuracy, CBCT model scan, desktop model scanner, digitalization, full-arch scans, intraoral scanner