Pages 229-238, Language: English, GermanReich, Sven/Troeltzsch, M./Denekas, Th./Wichmann, M.
The introduction of the Cerec 3D software (R 1500) promised the generation of functional occlusion points and proximal contacts on the basis of a 3-dimensional virtual model on the screen. The objective of this in vitro study was to check this claim in the simulated chairside production of a single tooth restoration. Furthermore, the differences both in conventional finishing and in ceramic glazing were to be determined. For the operator, the latter should simplify or shorten the intraoral finishing and polishing of the occlusal surface, or make it superfluous. To check the suitability of the two methods, these were compared with regard to their quality and the time required to perform them. Ten cavities on articulated models, representing real clinical cases, were each provided with two restorations. One was produced with the glazing method (group A), the other conventionally (group B). The Cerec 3D software, version R 1500, was used for designing the restoration. The restorations made from Vita Mark II ceramic blocks were finished with fine diamond instruments and polished with Sof-Lex disks when using the conventional method. In the alternative method, finishing was practically replaced by glazing the surface. The restorations were evaluated in the articulator, considering both the vertical relation at the incisal pin as well as the accurate position of the contact points. The study showed that functional rehabilitation was possible and no significant qualitative differences occurred in the methods. In this in vitro study, it was found that the glazing method reduced the time required by the operator by around 20% and indicates an improvement in quality. The results of this study promise simplification when the glazing method is used clinically.
Keywords: 3D occlusal surfaces, glazing, quality assessment, time expenditure
Pages 239-251, Language: English, GermanAsselmeyer, Theresia/Fischer, V./Matthies, H./Schwestka-Polly, R.
In der vorliegendenUntersuchung geht es um die Frage, inwieweit orts- und zeitunabhängig bereitgestellte computer-unterstützte Lerneinheiten ergänzend zum klassischen Präsenzunterricht von Studierenden der Zahnmedizin im Selbststudium genutzt werden. Hieraus sollen Hinweise abgelesen werden, ob solche Lehrbausteine die Ausbildung in der Kieferorthopädie verbessern. Im Zentrum stand die Implementation und Evaluation des Lehrbausteins "Kieferorthopädisches Set Up", der im Internet und Intranet der Hochschule bearbeitet werden konnte. Das didaktische Arrangement sah vor, dass neben den elektronisch vermittelten Lehrinhalten klassische Hochschulveranstaltungen parallel angeboten wurden (vier Vorlesungen zu den Themen Okklusion, Funktion, Diagnostik und Therapie). Zudem war eine intensive Betreuung während der Herstellung des "Set Up" gewährleistet. Ergebnisse: Der Einsatz dieses multimedialen Lernkonzepts wurde von 63 befragten Studierenden des WS 2002/03 grundsätzlich positiv beurteilt. Die differenzierten Ergebnisse lassen zum einen die Bearbeitungsintensität undMerkmale des Wissenserwerbs erkennen (Nutzungstypen), zum anderen wurden die bereitgestellten Inhalte im Blick auf die fachliche Relevanz als gut erläutert und didaktisch ansprechend und verständlich präsentiert eingeschätzt. Allerdings werden auch zahlreiche Hemmnisse thematisiert (technische und zeitliche Probleme; Qualifikationsdefizite). Die Projekterfahrungen können insgesamt dazu ermutigen, zukünftig mehr in die Entwicklung alternativer hochschuldidaktischer Modelle zu investieren.
Keywords: computer-unterstützte Lehre, E-Learning, Kieferorthopädie, Okklusion, Set Up
Pages 253-262, Language: English, GermanSchultze-Mosgau, S./Thorwarth, W. M./Grabenbauer, G. G./Amann, K.
The demonstration of patient case reports in the course of a clinical round is an essential part of teaching medicine and dentistry. However, suitable live patients with particular problems are not always available at a time when teaching is taking place. This project therefore had the objective of establishing a web-based, virtual e-learning concept for demonstrating case reports independent of time and place, with the possibility of an interactive examination, diagnosis, and interdisciplinary therapy decision making for medical and dental students.
Anonymized case reports of diseases in the oral and maxillofacial region and the interdisciplinary treatment were digitized and prepared in a web-based format. The technical aspect was based on connecting flash modules with videos and animation, and monitoring through HTML and Javascript. Due to the modular concept and the programming used, the learning environment was independent of platform and open. Independent formats (.swf, .avi, .mpeg, etc.) were integrated into the individual modules. According to a hierarchic decision system, the user was guided interactively to the diagnosis through a differential diagnostic exclusion process. Sound was digitized and integrated inmp3 compressed formin the 3Dmodels for lip-synchronous speech output. The speech output was connected with a virtual 3D tutor that acted in an advisory capacity in reaching a diagnosis and determining therapy. Further sources of informationand literature with abstracts or pdf files of the subject-related publications were inserted to ensure that the teaching was objective. To conclude the virtual clinical round, a check on learning success was conducted in the formof amultimediamultiple choice test.
Keywords: e-learning, teaching, internet, clinical round, online test, dentistry, medicine
Pages 263-267, Language: EnglishHuang, Li Chung
This report presents the use of Cerec veneers in the treatment of a female patient suffering from tetracycline staining and an anterior open bite. Because the latest Cerec 3D software did not include a veneer design program, only a correlation mode, the Cerec 3 veneer program was used.
Pages 293-301, Language: English, GermanDevigus, A./Lombardi, G.
All-ceramic restorations should reproduce as well as possible the color of the natural teeth to create a restoration in accordance with the esthetic wishes and ideas of the patient. The basic color of zirconiumoxide is white to ivory. The color can be partially adapted by veneering it with ceramicmaterials.However, it would be better if the substructure could already be adapted to the basic color shade of the neighboring teeth. In this study, the influence of differently shaded frameworks made of Y-TZP by Vita and 3M ESPE and by Enrico Steger (without, with 0.5 mm, or with 1.0 mm ceramic veneer with Base Dentin) on the brightness, saturation, and color shade (= value, chroma, and hue) was measured and assessed with the aid of a spectral photometer (EasyShade, Vita) in a clinical case in the mouth and on the model. By adaptation to the basic shade, the shading of substructures made of Y-TZP can help to reduce the necessary layer thickness of the veneer ceramic to achieve the desired color and should be performed in the future as a matter of routine. In this way, more substance can be conserved when restoring the teeth without having to accept an impairment of the esthetic result.
Keywords: Shading, Zirconium oxide, framework, ceramics