cosmetic dentistry_ beauty & science International Edition

I special _ digital smile design malpositioned teeth, gingival architecture discrep- ancies, improper axial inclination, dental midline deviation, or indications for maxillofacial surgery and/or orthodontic treatment (Fig. 4). Without the patient’s facial data, it is impossible to evaluate the smile and its harmony within the patient’s face properly. As part of the diagnosis, it is necessary to evaluate facial and dental asym- metries. As practitioners, we need to keep global aesthetics in mind by using a full facial view in the laboratory (Fig. 5). Close-up photographs of the patient’s smile aid smile design, but the complete facial photograph is required to evaluate the smile on the patient’s face.6 _Simulation Computer software creates a simulation as a virtual wax-up. The practitioner uses the virtual wax-up in the diagnostic process to determine the treatmentoptionsappropriateforthepatient,such asorthodontics,crowns,implants,bridges,orfullor partial dentures. This process aids the practitioner in presenting and discussing different options with the patient during a consultation (Fig. 6). The diagnosis and treatment planning use the M Ruler. This diagnostic tool for smile design uses an algorithm based on maxillary central incisors width and the width of the patient’s maxillary arch to display an ideal arrangement of all the teeth shown in the smile (Fig. 7). Each patient has a unique maxillary arch width and upper central width. Maxillary teeth best position should be dis- posedbetweenthoselinesinrespectofthewidthof theupperarchandthewidthofthecentralincisors. Theseverticallinesguideprofessionalsindetermin- ingthebestpositionofthemaxillaryarchandteeth inrelationtothepatient’sfaceandinrelationtothe patient’s lips and gingiva for smile design. The computer software simulation or virtual wax-upcanbegeneratedwithinminutes,andhelps (or guides) the clinician in determining treatment options, which can be discussed with the patient during the same consultation. In this particular clinical case, the simulation suggested longer central incisors to create a smile line that would follow the lower lip and lend a more pleasing proportion to the smile. Tooth whitening was also indicated (Fig. 8). _Communicating with the laboratory After the virtual diagnostic wax-up, the patient was informed of the treatment options, including notreatmentatall,andtherisks,benefits,andcosts of treatment. Informed consent was obtained for the treatment, which entailed placing ten veneers from the second premolar to the opposite second premolar on the maxillary arch and ten veneers on the mandibular arch. Once the simulation (Fig. 8) had been accepted bythepatient,alginateimpressionsofthemaxillary and mandibular arches were poured with white stone and sent to the laboratory with a bite regis- tration6, 7 taken using LuxaBite (DMG America). The aesthetic prescription was sent to a certified dentallaboratory,whichmountedthe3-Dmodelon to an articulator in accordance with the GPS smile prescription and waxed up the final work follow- ing the future smile line (Figs. 9a & b). Because of the image’s calibration, the wax-up coordinates are very precise (Fig. 10). Laboratory communication is a critical factor in the development of a diagnostic wax-up. In order to reproduce the simulation (virtual wax-up), the laboratory technician requires the position of soft Fig. 7_The M Ruler. Fig. 8_The before and after simulation usually shown to the patient at the end of the first consultation. Figs. 9a & b_The prescription resulting from the software (a) gives the laboratory the co-ordinates necessary to mount the model on to the articulator and to wax up the final work. Specific guidelines help the technician to create a very precise wax-up of the future smile (b). 14 I cosmeticdentistry 1_2014 Fig. 7 Fig. 8 Fig. 9a CDE0114_12-16_DelCorso 11.06.14 14:03 Seite 3