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Digital photography has already established its irrefutable importance in today's world. It is becoming an indispensable tool in various fields. In dentistry specifically, photography can be employed in several ways that can be beneficial to the patient and the dental community. It allows a simple and clear depiction of an otherwise abstract concept, but high-quality pictures are always required. The evolution of mobile cameras has made an enormous impact on digital photography and its accessibility: high-quality pictures can now be easily taken. This article explains the assets of smartphone cameras' evolution and how it led to the conception of Smile Lite Mobile Dental Photography. Applications of dental photography are presented, such as documentation and communication with the laboratory technician and the patient. Mobile dental photography is not confined to dentistry but can also be used for artistic purposes. (Quintessence Int 2020;51:510–518; doi: 10.3290/j.qi.a44365; Originally published (in German) in Quintessenz Zahnmedizin 2019(12);70:1408–1417) Keywords: communication, documentation, mobile dental photography, smartphone

Aim: To evaluate the fracture resistance and failure pattern of 3D-printed and milled composite resin crowns as a function of different material thicknesses. Materials and methods: Three typodont tooth models were prepared to receive a full coverage composite resin crown with different thicknesses (0.5, 1.0, and 1.5 mm). The prepared master casts were digitally scanned using an intraoral scanner, and the STL files were used to fabricate 60 nanocomposite crowns divided into two groups according to the material thickness (n = 10) and fabrication method: a 3D-printed group (3D) using an SLA printer with nanocomposite, and a milled group (M) using a milling machine and composite blocks. All crowns were adhesively seated on stereolithography (SLA)-fabricated dies. All samples were subjected to thermomechanical loading and fracture testing. The load to fracture [N] was recorded and the failure pattern evaluated. Data were statistically analyzed using a two-way ANOVA followed by a Bonferroni post hoc test. The level of significance was set at α = 0.05. Results: The 3D group showed the highest values for fracture resistance compared with the milled group within the three tested thicknesses (P 0.001). The 3D and M groups presented significantly higher load to fracture for the 1.5-mm thickness (2383.5 ± 188.58 N and 1284.7 ± 77.62 N, respectively) compared with the 1.0-mm thickness (1945.9 ± 65.32 N and 932.1 ± 41.29 N, respectively) and the 0.5-mm thickness, which showed the lowest values in both groups (1345.0 ± 101.15 N and 519.3 ± 32.96 N, respectively). A higher incidence of irreparable fractures was observed for the 1.5-mm thickness. Conclusion: 3D-printed composite resin crowns showed high fracture resistance at different material thicknesses and can be suggested as a viable solution in conservative dentistry. Keywords: additive manufacturing, 3D printing, composite crowns, CAD/CAM, fracture resistance, failure pattern

Die digitale Fotografie ist in den letzten Jahren zu einem unverzichtbaren Werkzeug in den unter-schiedlichsten Bereichen geworden. Speziell in der Zahnmedizin kann die Fotografie auf verschiedene Weise zum Nutzen sowohl des Patienten und auch des behandelnden Teams eingesetzt werden. Sie ermöglicht u. a. eine einfache und übersichtliche Darstellung ansonsten abstrakter Konzepte. Allerdings müssen die erstellten Aufnahmen von entsprechender Qualität sein. Im Zuge der rasanten Entwicklung der Smartphone-Kameras ist die digitale Fotografie mittlerweile für nahezu jedermann zugänglich, und mit einfachsten Mitteln gelingen jetzt hochwertige Bilder. Der Beitrag geht zunächst auf die Smartphone-Kameras ein und erläutert, wie sich das Konzept der mobilen Dentalfotografie mit dem Belichtungsgerät Smile Lite MDP herausgebildet hat. Danach werden zahlreiche Anwendungen der Dentalfotografie z. B. zur Dokumentation oder für die Kommunikation mit dem Labor vorgestellt. Abschließend wird noch aufgezeigt, dass die mobile Dentalfotografie nicht auf rein medizinische Aufgaben beschränkt ist, sondern auch für künstlerische Zwecke genutzt werden kann. Keywords: Mobile Dentalfotografie, Dokumentation, Kommunikation, Smartphone, Smartphone-Kamera