case report 10 11 12 5 Fig. 10: Central incisor with GC Initial IQ Lustre Pastes NF CL-F. Fig. 11: Colour firing with GC Initial IQ Lustre Pastes NF CL-F. Fig. 12: Enamel firing. durable provisional restorations. For cases like this, the comfort of the patient is always the priority. Hence, after six months, the definitive im- pressions were taken, both digitally and conventionally. The conventional impression was used to create the master working model. This was mostly due to familiarity with the procedure. We feel that what we are mentally comfortable with will also yield the best possible end result. However, a digital impression could have been used as well. For the substructure, multilay- ered zirconia (Shade A2) was used. The design was a small, adapted copy of the provisional restorations. A 0.4 mm buccal cut-back was done for the posterior teeth and the canines. For the four anterior teeth, a 0.6 mm cut-back was done and the incisal height was decreased by 0.4 mm. To maintain control of the horizontal line, a palatal putty index of the provisional restorations was made for use as a key during the ceramic build-up (Figs. 5a & b). The zirconia substructure was slightly adapted and went into the furnace for a regeneration firing. Thereafter, the workflow continued with the wash firing. After application of the GC Initial IQ Lustre Pastes NF (Fig. 6a), the Initial CL-F (Clear Fluo- rescence) powder was sprinkled on top of the wet paste (Figs. 6b & c). This gave the opportunity to sandblast af- ter the wash firing without damaging the colour. Moreover, it ensured that the colours would not slip down. Zirconia does not absorb heat well, and the heat must be carefully adjusted to avoid chipping. The prob- lem of chipping is also a consequence of poor adjustment of the heating program. The larger the volume of 13a 14a 13b 14b 15 16 zirconia, the slower the heating up and cooling down should take place. In this case, the heating temperature was dropped by 30 °C per minute, and the cooling down should have a similar rate. To keep it simple: the time to heat up should be more or less the same as the cooling down. a softer transmitter of the colour. This mixture can also be used as a transi- tion towards the enamel in the incisal third; however, in this case, it was used as a softer, lighter cervical part. It is all about breaking the light with a chameleon effect inside the material. The part until the CL-F was the first layer. For the neck, IN-42 (Terra- cotta; 40%) was used with A2 (60%), and then the main colour was A2 (Fig. 7). After applying DA2 to the full contour (Dentin A2), the horizontal line was checked with the putty key (Fig. 8). After the cut-back, the mamel- ons were shaped. FD-91 (Fluo Dentin Light; 50%) with DA2 (50%), A1, and A1 (50%) with E58 (Enamel; 50%) were alternated, as shown in Figures 9a and b. In the cervical part, this mixture was also used. This mixture could be called an enamel blocker; it works as Bob Bosman Elst graduated in 1991 as a dental technician. While working at his own independent dental laboratory in Belgium, he has continuously been working on expansion and developing innovative techniques for the dental industry. Over the years, he has partici- pated in more than 40 master courses, including those by Brüsch, Tyszko, Cal- garo, Adolfi, Galle, Hegenbarth, Sieber and Polansky, either as a lecturer or as an active participant. His work has been recognised by many in the field. In 2007, Elst won the third prize (in the Young Ceramics category) during the world tour of Nobel Biocare in Las Vegas in the US. He came in as the first European of all the participants in this highly reputable event. He set up a help desk for dentists, covering all aspects of implant-supported restorations and porcelain. In 2017, he became a trainer of the GC Europe Campus, where he found the perfect forum for sharing his passion and experience. Dr Marco Tudts graduated as a dentist from KU Leuven in Belgium in 1991 and completed his postgraduate qualifica- tion in aesthetic and prosthetic dentistry in 1994. For 12 years, he was a part- time associate at KU Leuven, complex rehabilitation being his major research topic, and participated in various mul- ticentre studies. In 1996, he started a multidisciplinary private practice, specialised in complex rehabilitation, which he is still running. In 2004, he obtained an MSc in dental implantol- ogy from Montefiore Medical Center in New York in the US. In 2008, he opened a look-over-shoulder training facility for dentists focusing on implantology, 3D technology, CAD/CAM and 3D-guided surgery. He is the developer of the Navi- gator System for guided surgery (Zimmer Biomet Dental). Since 2015, he has been a staff member in the Department of Oral Health Sciences at Ghent Uni- versity in Belgium. Here, he is currently preparing his PhD dissertation on 3D- guided surgery under Prof. H. De Bruyn. This article originally appeared in CAD/CAM—international magazine of dental laboratories, vol. 12, issue 1/2021. If the mamelons are to be clearly distinguished from the dentine mate- rial, CL-F should be applied on top of the mamelons (Fig. 10). For floating mamelons, a wall of CL-F is applied to the cut-back, then the mamelons are created and then again a layer of CL-F is applied. In this case, it was chosen to have the mamelons differentiated from the dentine material. This first bake is the colour firing (Fig. 11); if the colour is not chromatic enough or already too chromatic, it is easier to adapt in this phase. After application of the enamel material, colours should no longer be adapted because this will destroy the appear- ance, which could become very greyish. The enamel firing could be con- sidered the morphological firing. For the enamel, a mixture of E58, EI-14 (Enamel Intensive Yellow) and EOP Booster in three equal parts was used (Fig. 12). The program was ex- actly the same as for the colour firing. The correction firing was done with the same mixture, but diluted with a fourth part of CL-F (Figs. 13a & b). The temperature was dropped by 5 °C. In case another firing is neces- sary, the temperature can be dropped by an extra 2 °C. After finishing of the structure, the crown was glazed with just some liquid, at 50 °C lower than normal. The intention was to seal the surface. After this firing, the crowns were hand polished with a mixture of pumice and 50 µm aluminium oxide (Figs. 14a & b). The preparations were cleaned and isolated with retraction cords (Fig. 15). The crowns were cemented with a resin-modified glass ionomer (GC Fuji PLUS CAPSULE, GC). The cement excess was easily removed when the rubbery state was reached, and margins were polished. Increasing the vertical dimension is often a challenging task. The tem- porisation phase was used to evalu- ate the influence of the increase on the temporomandibular function. Aside from the function, restoring the vertical dimension had a positive in- fluence on the aesthetic appearance. After treatment, a better balance in the facial dimensions as well as a fuller, more youthful smile could be seen (Figs. 16–18). 7 17 18 5 Figs. 13a & b: Correction firing. Fig. 14a: Restorations before polishing. Fig. 14b: Restorations after polishing. Fig. 15: Prepared teeth before luting. Fig. 16: Final result in intercuspal position. Fig. 17: Night guard to protect the restorations and periodontal tissue. Fig. 18: Final result, portrait. The patient was satisfied with the aesthetics and function of his new smile. AEEDC Dubai 2021 · 29 June to 1 July 2021 17