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I 31 industry report _ IPS Empress CAD Multi I CAD/CAM 2_2010 Based on her wishes, an anamnesis and a diag- nostic analysis were conducted. In the next step, I set up a treatment plan that included teeth #11, 12, 21 and 22. First,Ifabricatedamock-up,whichwastoserve as a basis for the discussion with the patient. Her wish of having teeth with a more rounded shape and thus with a softer, more feminine appearance was taken into account during the fabrication of the mock-up. The teeth were prepared according to standard procedures (Fig. 3). A fibre-reinforced endodonticpostandcorewasseatedintooth#12. This was done to prevent root fracture but still ensureanaestheticrestorativeresult.Intooth#11, caries was detected in the area of the mesial angle. Following removal of the carious tissue, the cavity wasfilledwithcompositeresin.Tooth#21received a full-crown preparation. A rounded shape was preparedtoensureevendistributionoftheforceto which the restoration would be exposed. In tooth #22, composite material was applied in the area of the medial angle. The CEREC software features a tool termed correlation mode. This mode enables users to take an optical impression. As the patient had a very clear idea of the future appearance of her teeth, I decided to use this mode to match my ideas with hers. Therefore, a silicone impression was taken aftertheteethhadbeenpreparedandamodelwas poured (Fig. 4). Based on the mock-up, which had been dis- cussed with the patient earlier, a wax-up was cre- ated on the model and an optical impression was taken(Fig.5).Therecordedmodelservedasaguide for the construction procedure, which was carried out using the quadrant mode. In the fabrication of anterior restorations, it is advisable to check the size and dimension of the incisalbuild-upfromthepalatalaspectcontinuously by means of a silicone matrix. This significantly fa- cilitates the modelling procedure. Moreover, by pro- ceedinginthiswayitbecomesapparentimmediately ifdatahasbeenlostduringopticalimpressiontaking. A loss of information in the area of the incisal edge usually renders the construction of anterior restora- tionsconsiderablymoredifficult.Thepreciserecord- ing of data is of utmost importance, especially if the patient requests a particular tooth shape (Fig. 6). The 3.6 version of the CEREC 3D software has a milling preview feature, which allows users to ‘place’therestorationinthevirtualblockasneeded in accordance with the gradation of shades from cervical to incisal (Fig. 7). This enables the operator to make use of the opaque/translucent areas or the gradation pattern of the block in an optimal fashion. If several teeth are restored simultane- ously, there are now various options to utilise the different areas efficiently. Consequently, it is even possible to fabricate restorations that do not re- quire individual characterisation or cutting back. Fig. 4_The die model constituted the basis for the mock-up. Fig. 5_Creation of the wax-up; as desired by the patient, tooth shapes that were more rounded were established. Fig. 6_The restoration was designed on the computer screen. The silicone matrix was scanned in order to be able to construct the incisal area easily and quickly. Fig. 7_Virtual positioning of the restoration in the IPS Empress CAD Multi block.Fig. 7Fig. 7 Fig. 5Fig. 4 Fig. 6