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32 DIGITAL DENTISTRY Dental Tribune Middle East & Africa Edition | 2/2017 Hands-On Training in Dubai Digital Smile Design Part 1 Tutor: Dr. Eduardo Mahn, Chile Date: 01 May 2017 | 09:00 - 18:00 Venue: InterContinental Hotel Festival City, Dubai, UAE Target Audience: Dentists Digital Smile Design Part 2 Tutor: Dr. Eduardo Mahn, Chile Date: 02 May 2017 | 09:00 - 18:00 Venue: InterContinental Hotel Festival City, Dubai, UAE Target Audience: Dentists Join Hands-On Training 01-02 May 2017 www.cappmea.com/cadcam DUBAI Course Abstract The course will fi rst present the necessary theoretical backround about DSD with a short summary of it. Then tips and tricks about photo-video and how to analize the patients from the facial per- spective are going to be given. Facial, smile and tooth references are going to be given. The course will also provide the participants with written material explaining several techniques presented during the lectures. Course Objectives The participants will learn to: 1. Take pictures of the patients with any smartphone 2. Make a simple but effective video fundamental for any diagnostic process 3. Perform the Digital Smile Design protocol on their computers 4. Apply different esthetic parameters on the analysis of their patients 5. Correct effi cient wax-ups 6. Perform a mock-up 7. Document the mock-up and show it in an emotional way to the patient The rise of digital dental restorations By Brendan Day & Marc Chalupsky, DTI Composite-based CAD/CAM mate- rials have been marketed as com- posite ceramics or hybrid ceramics to underscore their longevity. The latest generation of reinforced com- posite blocks demonstrates excel- lent material properties, which are in part even superior to those of ce- ramics. In order to investigate this, Dr Ralf Boehner, a leading expert on composite-based CAD/CAM materi- als, recently compared the material properties and luting strategies of certain reinforced composite blocks to those of ceramics. Digital production is becoming in- creasingly popular in the fabrication of dental restorations. In this process, the restorations are ground to their fi nal shape using digital data sets. These digitally produced restora- tions have often used ceramic-based materials. Although these ceramic materials have good aesthetics and resist abrasion, they also have draw- backs, including a relatively high modulus of elasticity, a tendency to chip and abrasion of the antagonist. Furthermore, modifying or repairing ceramics intra-orally is quite an elab- orate procedure. Therefore, there is a need for composite materials for use with the CAD/CAM method, in addi- tion to light-curing composites, for permanent restorations. What is a composite? A composite is generally described as a material consisting of two or more different components that are bond- ed to each other. CAD/CAM compos- ites consist of a matrix of polymer- ised methacrylates, which contain different fi llers (glass or ceramic), de- pending on the product. Composites must not be confused with purely ceramic CAD/CAM materials or treated as such. For example, as com- posite materials should not be fi red, their processing procedure is consid- erably easier. In addition, adhesive luting is adapted to the composite. Similar to light-curing fi lling mate- rials, composite-based CAD/CAM materials are easy to modify and polish. Furthermore, their repair can be performed intra-orally. In general, the luting strategy of CAD/CAM-fab- ricated restorations is crucial for the success of treatment. Material properties Compared with ceramics and poly- mer-infi ltrated ceramics, CAD/CAM composites have a lower modulus of elasticity and therefore they damp- en masticatory forces far better and promote comfort while chewing. Physical studies have also confi rmed that CAD/CAM composite materials have excellent mechanical proper- ties. Compared with a tested ceramic material (IPS Empress CAD, Ivoclar Vivadent) that does not need to be fi red after the grinding process, both Lava Ultimate (3M ESPE) and BRIL- (Coltène/Whaledent) LIANT Crios demonstrated fl exural strength. higher Performance in the mouth It is known that ceramic materials can lead to increased abrasion of the antagonist during mastication com- pared with dental enamel. Owing to their lower modulus of elasticity and their composition, composite ma- terials should cause less abrasion of the antagonist. Interesting results on this matter were obtained in a study of the abrasion of CAD/CAM materi- als of the dental enamel antagonist. The CAD/CAM composite materials demonstrated less abrasion of the enamel antagonist compared with the tested ceramic materials and the polymer-infi ltrated VITA ENAMIC hybrid ceramic (VITA Zahnfabrik). According to the study, BRILLIANT Crios is gentle on antagonists, as is usual for composite materials, and yet it results in low abrasion, similar to ceramics. Luting strategy In contrast to pure ceramic mate- rials, CAD/CAM composites must always be luted adhesively, though the exact procedure differs for each composite. The following explains the luting strategy both in general and specifi cally for BRILLIANT Crios. In this case, the composite is made of a dental glass and a matrix of polymerised resin, and the resin ma- trix also contains non-polymerised methacrylate double bonds. After the restoration has been fabricated, the surface to be bonded is sand- blasted to enlarge the surface and to create mechanical retention. This surface then contains particles of dental glass and the polymerised res- in matrix. As sandblasting is a very abrasive process, care should be ex- ercised so not too much substance is removed. The effect of the sandblast- ing procedure is comparable to a pretreatment through sandblasting with corundum for zirconia or etch- ing with hydrofl uoric acid for silicate ceramics. In all cases, the result is an enlargement of the surface and the establishment of mechanical reten- tion. Improvement of the adhesive bond The strategy for achieving a perfect adhesive bond varies, depending on the composition of the CAD/CAM composite material. The process should be as simple as possible to avoid potential errors in application that may negatively affect the adhe- sive bond. In general, the following rules apply: • Maintain an enlarged surface for bonding and creating mechanical retention. • Bond to the fi ller materials. • Bond to the polymerised resin ma- trix. Adhesion to tooth substance In the case of light-curing bonds, similar to the case with conven- tional fi lling therapy, the light cur- ing should follow the instructions for use after application to the tooth substance. Furthermore, the lut- ing material used should not be too opaque. Otherwise, not enough light may penetrate the restoration to reach the uncured inhibition layer of the bond during fi nal light curing. In such cases, dual-curing or chemically curing bonds are indicated. Conclusion Composite-based CAD/CAM mate- rials are very similar to light-curing fi lling materials in terms of their design; thus, they are just as easy to modify and polish after the grinding process. Shade adaptations or modi- fi cations—for example, to create a contact point—are easy to realise with the appropriate adhesive tech- nique and composite. Compared with light-curing composites, CAD/ CAM composite materials are fabri- cated extra-orally under perfect in- dustrial conditions; therefore, they demonstrate improved mechanical properties.