Pages 13-25, Language: English, GermanMehl, Albert/Blanz, V.
The goal of this study is to present a completely new procedure for automatic occlusal surface reconstruction and to test it in several inlay situations. The starting point is the mathematical analysis of a large number of occlusal surfaces from a tooth library. Learning algorithms used in pattern recognition and image processing were adapted for the special needs of dental morphology. A biogeneric tooth model resulted which can mathematically describeacertain type of tooth only with a few parameters. This model was tested on 40 simulated inlay situations and as an example on two clinical inlay situations. The results show that fully automatic reconstruction was possible except for four cases. In a majority of the cases, no further interactive improvements would have been necessary. Because of the general, theoretically wellfounded approach, fully automatic reconstruction of the occlusal surface can also be extended in the future to full crowns or reduced crown substructures (copings).
Keywords: CAD, occlusal, occlusal surface reconstruction, biogeneric, tooth model, inlay, onlay
Pages 47-58, Language: English, GermanReich, Sven/Wichmann, M./Bürgel, P.
When previously using Cerec 3D, the occlusal surface could be designed according to morphologically functional aspects with the aid of a bite registration (static and/or dynamic). In addition, different tooth databases could be used for the design of crowns. However, the relevant design suggestion had then to be manually aligned onto the functional registration by the user. The new Cerec 3D software version R 2005 now promises the automatic adjustment of crown proposals in alignment with the corresponding functional registration. In this case, the crown design selected from the tooth databases is adjusted to the morphology of the functional registration and is thereforemodified until light contact points are still present. The procedure of the "selfadjusting crown" is demonstrated by reference to a clinical case. As the name "self-adjusting crown" indicates, this automatic tool is possible only in restorations which have a single-segment preparation margin (crowns).
Keywords: crown, occlusal suface, software, FGP, CAD/CAM
Pages 59-68, Language: English, GermanWiedhahn, Klaus
Vor der Einführung der Version R1800 stand dem Cerec-Anwender zur Veneerkonstruktion nur die CORRELATION zur Verfügung,1 und für die konstruktive Veneerherstellung musste auf das alte Cerec 3-Programm zurückgegriffen werden. 2 Die Software R1800 stellt nun auch eine Zahndatenbank für Veneers bereit und erlaubt das Kopieren und freie Einfügen von beliebig aufgenommenen Zahnformen. Mit der Version R2005 wurden die Bearbeitungsmöglichkeiten beim Veneerdesign weiter optimiert und auch das Kopieren, Spiegeln und Einfügen von Kronen ermöglicht. Die situationsbezogene Auswahl der Konstruktionsverfahren CORRELATION, ZAHNDATENBANK und REPLICATION soll anhand von klinischen Beispielsituationen dargestellt und bewertet werden.
Keywords: CAD/CAM, Veneer, Cerec Chairside, Veneer- Software
Pages 77-84, Language: English, GermanKurbad, Andreas/Reichel, K.
Anew device for digitizing model surfaces for dentalCAD/CAMapplications is available with the inEOS scanner. It works according to the principle of stripe light projection. Both rotational scan mode of single prepared teeth and overview scan mode in which a complete model of the jaw can be acquired are possible. Detailed scans can be taken in addition to improve the data quality. The software basis is the proven Cerec inLab 3D program. The virtually produced restorations can bemilled either with the inLab milling unit or transferred to the Infinident milling center for central production. A clinical case which was treated by using the inEOS scanner is presented.
Keywords: CAD/CAM systems, surface digitization, full ceramics