PubMed ID (PMID): 19413268Pages 119-130, Language: English, GermanArnetzl, Gerwin V. / Arnetzl, Gerwin
Purpose: In this in vitro study, all-ceramic inlays were subjected to a static strength test. The material used in this case was Vita Mark II® ceramic (Vita-Zahnfabrik, Bad Säckingen, Germany). The goal of the study was to evaluate two different inlay preparations with differently designed ceramic inlays resulting from it, to determine which offered the greatest possible resistance in static fracture loading tests. Materials and Methods: Tooth 36 on the model, provided with a standard preparation with a level floor, served as the test object. Two inserts were produced: one with classical preparation pattern, the other with a modified shape of the cavity floor. In one inlay design, the cavity floor was designed according to the guidelines valid for all-ceramic inlay restorations; in the second inlay design, a differently shaped cavity floor was selected to exclusively meet the requirements of the ceramic material. Impressions were then taken, and inlays were designed and produced by means of CAD/CAM technology. Results: Lower fracture strength with mean fracture load values of ca 66.6 N was shown for traditional inlay preparations with a cavity floor segment designed as box. The mean fracture strength of the inlay design consisting of the same material with a hemispherical cavity floor segment was 84.9 (N), 27.5% greater. Conclusion: The question arises whether it is possible, independently of the ceramic used, to achieve an increase in strength by modifying the design of the inlay.
Keywords: preparation design, FE analysis, inlay design
PubMed ID (PMID): 19413269Pages 131-145, Language: English, GermanRugani, Petra / Kirnbauer, Barbara / Arnetzl, Gerwin V. / Jakse, Norbert
Zur Diagnostik knöcherner Pathologien, Planung komplexer implantatgetragener prothetischer Behandlungen und zur Gewährleistung möglichst sicherer und komplikationsarmer oralchirurgischer Eingriffe, ist häufig eine dreidimensionale radiologische Darstellung angezeigt. Eine Alternative zur Computertomografie stellt die digitale Volumentomografie (DVT) dar, die einen Großteil der Indikationen des zahnärztlichen und oralchirurgischen Indikationsspektrums abdecken kann. Darüber hinaus bietet die Methode den Vorteil, dass sie unter Berücksichtigung der bestehenden Strahlenschutzbestimmungen auch in der zahnärztlichen Praxis eingesetzt werden kann. Dies gewährleistet eine optimale Patienten- und Anwenderfreundlichkeit, weil die Überweisung an ein spezialisiertes CT - Institut damit in den meisten Fällen nicht mehr notwendig ist. In den ersten 12 Monaten der Teststellung des Planmeca Promax 3D® am Depart-ment für Zahnärztliche Chirurgie und Röntgenologie der Universitätsklinik für Zahn-, Mund- und Kieferheilkunde Graz befasste sich mit knapp 90% der überwiegende Teil der Zuweisungen zur DVT mit Fragestellungen aus den Bereichen der oralen Chirurgie und der Implantologie. Oralchirurgische Fragestellungen hatten hauptsächlich Aspekte der Weisheitszahnanatomie, Lage von retinierten Eckzähnen, Prämolaren und Mesiodentes, sowie zystische Läsionen zum Inhalt. Die Kieferhöhlendiagnostik und der Bereich der Zahnerhaltung stellten weitere Indikationen dar. Ziel der Zuweisungen war neben der Diagnosefindung, die Ermöglichung einer optimalen Vorbereitung auf den bevorstehenden Eingriff. Im Bereich der Implantologie war dies häufig kombiniert mit einer prä- oder postaugmentativen dreidimensionalen digitalen Behandlungsplanung. Die DVT zeigte gute Ergebnisse bei der Darstellung von Hartgewebsstrukturen und ließ sich problemlos in den täglichen Klinik-Betrieb integrieren.
Keywords: CBCT, CT, Oralchirurgie, Radiologie, computergesteuerte Implantatplanung, 3-dimensionale Diagnostik
PubMed ID (PMID): 19413270Pages 147-156, Language: English, ItalianBonaudo, Diego / Boschis, D. / Gianpaolo, R.
The continuing development of innovative surgical and prosthodontic techniques has led to a greatly increased interest in and demand for restorations on immediately loadable implants, due to the numerous clinical advantages offered by this treatment mode. By now, numerous clinical observations supported by histological studies have shown that dental implants placed in fresh extraction sockets with subsequent immediate loading result in clinical success.1 Software-assisted approaches to prosthetically driven surgery combined with CAD/CAM methods can result in highly esthetic and functional all-ceramic restorations for single missing teeth or more extensive edentulous areas using an immediate-loading protocol. The most important objectives in this respect are to reduce treatment times, prevent postextraction bone resorption, and preserve the residual periodontal tissues. Implant-supported restorations have become a frequently employed treatment method for the partially or completely edentulous jaw, well documented in long-term observations and histological studies of the osseointegration process.1-4 Numerous treatment protocols have been proposed and employed, depending on the number and distribution of implants used, to obtain a functional rehabilitation, using diagnostic templates during the restorative process to ensure a better axial alignment of the transmucosal units relative to the occlusal load.12 The choice of implant in terms of shape and diameter must be consistent with immediate functional loading with a provisional or definitive restoration, taking into account the effects and specifics of the occlusal loading situation as well as the need for conditioning the soft tissues. Primary stability, biological stability and the BIC (bone-implant contact) index all define the basic parameters of osseointegration, just as with the treatment modalities and osseointegration processes associated with conventional loading protocols.6-11 In this case report, the surgical procedure was driven by the subsequent restoration. We describe the chairside definitive restoration of a single missing tooth 3513 in a single visit by placement of a tapered, immediately loaded implant, a titanium/zirconia abutment, and an all-ceramic crown, including tollow-up and evaluation of the clinical result.
Keywords: prosthetically guided surgery, immediate loading, CAD/CAM technology, all-ceramic restorations
PubMed ID (PMID): 19413271Pages 159-163, Language: English, GermanZiegler, Markus
In February 2008, the Lava™ Chairside Oral Scanner C.O.S. (Fig 1) was successfully launched by 3M ESPE (St Paul, MN, USA) in the United States. In German dental practices, the test phase started in October 2008. In Germany, the new intraoral scanner for direct digitization of teeth will be available in April 2009. The method of data capture of the Lava™ C.O.S. is based on the novel 3Din- Motion technology. This technology was developed by Brontes Technologies (Lexington, KY, US), which was founded by former employees of the Massachusetts Institute of Technology (MIT) and acquired by 3M in October 2006. First study results prove the reproducibly high precision of the Lava C.O.S.
PubMed ID (PMID): 19413273Pages 171-185, Language: English, GermanKurbad, Andreas / Schnock, Heinz A.
Both pressing technology and CAD/CAM methods have proven themselves clinically for the fabrication of allceramic restorations. The advantages of the Cerec technology for the economic fabrication of all-ceramic bridges can be exploited by the use of burn-out blanks of polymer material. The milling process of very hard ceramics in the milling unit, which has some disadvantages, is replaced by the pressing process and makes the IPS e.max press material accessible to CAD/CAM users, primarily for extending the range of indications to splinted crowns and small all-ceramic bridges.
Keywords: all-ceramic, CAD/CAM technology, pressing technique, lithium disilicate.