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Dental Tribune Middle East & Africa Edition | 4/2016 14 RESTORATIVE Designing real smiles with digital tools By Drs Eduardo Mahn, Gustavo Mahn, Carlos Cáceres, Luis Bustos, Chile&ChristianCoachman,Brazil Dental materials and clinical proce- dures have changed dramatically in the last decades. Probably the major advances that have occurred during thelasttwodecadeshavebeeninthe fields of implantology and adhesive dentistry, but the main revolution is thedevelopmentofdigitaldentistry. Although these changes have cer- tainly made diagnostics and certain procedures easier, the basics, such as function and the biological as- pects, remain essential. At the same time, we have experienced major improvements in ceramics and composites, helping us to fulfil our patients’aestheticdemands. A basic prerequisite for these indica- tions is an in-depth understanding of the facial and dental aesthetic parameters. The clinician needs to understand the challenges that each clinical case presents and has to be able to develop an appropriate treat- ment plan that approaches the case from a multidisciplinary perspec- tive. Tooth proportions need to be considered in relation to gingival aestheticsandinrelationtothefacial appearance. It is pointless to make the most beautiful direct veneer if the contours or the texture do not match that of the adjacent teeth or the gingival zeniths are clearly not symmetric and visible. As an exam- ple, if we add a tilted occlusal plane or a maxillary tooth midline shift in relation to the facial midline, the results can be frustrating. Another importantaspectistheproperanaly- sis of the patient’s smile and display (Figs. 1 & 2). When photographs are taken,peopletendtobeshy,especial- lyatthebeginningandevenmoreso ifthepersontakingthephotographs is not a professional photographer and the setting is a dental practice. Figure 3 shows the intra-oral view, where, besides the obvious diastema and the hypomineralised areas of both central incisors, the major dis- coloured areas of both mandibular lateral incisors, which were certainly in need of some sort of treatment, are apparent. It is important to try to make a video while conversing with the patient about normal daily issues to avoid overlooking aspects that need to be considered in the treatment plan. The conversation will relax the patient and evoke nat- ural smiles and laughs in response to something humorous or silly that we might say. Figure 4 shows the dif- ferences between the social smile we achieved with our traditional pho- tographs (Figs. 1 & 2) and the spon- taneous smile, which was captured during dynamic recording. In this particular clinical case, had we based our treatment plan on the social smile photograph, we would have failed to visualise the display of the mandibular incisors, which showed unpleasantstains. The next step was to analyse the patient from the facial perspective based on the details of her teeth. The digital smile design (DSD) concept diagnoses aesthetic problems from a facial perspective and, based on a simplified digital analysis of a few photographs, proposes treatment options and assists with communi- cation between the various special- istsintheteam. The first step is to draw a horizontal and a vertical line. The photograph is centred, moved and rotated until the bi-pupillary line is horizontal. The facial midline is subsequently ascertained. Then the same lines are superimposed on to a similar photo- graph, which has also been centred, but this time taken with lip retrac- tors in place (Figs. 5a–c). The same photographsarethenmagnifiedand analysed (Figs. 6 & 7). The upper lip line is recreated and then superim- posed on to the photograph taken with lip retractors in place as refer- enceofitsposition(Figs.8&9).Then the tooth proportions are measured and their ideal contours are drawn (Figs. 9 & 10a). The isolated situation canbeseeninFigure10b. A photograph taken from the 12 o’clockpositionisusedfortheanaly- sisofthelabio-palatalpositionofthe teeth and superimposed on to the analysisdonepreviously(Fig.11). Once the clinician is clear about the treatment possibilities and limita- tions, a digitally designed mock-up canbecreated. This procedure reduces chair time dramatically and increases patient acceptance. Owing to easily accessi- ble software such as Microsoft Pow- erPoint and Keynote, these effects areeasilyandquicklycreatedbyany- one with minimal training. Recently, new software has been released that simplifies the procedure even more, DSD software for iPads (www.digital- smiledesign.com). The procedure is based on overlapping certain areas of the teeth in the manner previous- ly described. The result can be seen in detail in Figure 12 and the display in Figure 13. A comparison from the facial perspective between the pre- operative situation, the traditional mock-up and the digital mock-up can be seen in Figure 14. Traditional indirect mock-ups are made from a previously created wax- upfromthelaboratory. First, an impression is taken and a stone cast is then fabricated. After- wards, the technician waxes the necessary teeth depending on the instructions given by the clinician. The next step is taking an impres- sion from that wax-up. The excess is removed and a flowable selfor dual-curing composite material (usually bis-acrylic based) is applied to the silicone guide and then placed in the patient’s mouth. After a few minutes, the excess is removed and the patient is able to see the changes and the clinician is able to evaluate the proposal directly in the mouth. Generally, photographs are taken of the new situation and analysed. The option of a digital mock-up is much simpler. Once the final forms have been created, a photograph is super- imposedontothem,andthetexture ofthenewteethiscreated.Asseenin Figure 14, the results of the tradition- alandthedigitalmethodsaresimilar Fig.1 Fig.2 Fig.3 Fig.4 Fig.5 Fig.6 Fig.7 Fig.10b Fig.9 Fig.12 Fig.8 Fig.11 Fig.10a Fig.13 ÿPage 15 Join Dr. Eduardo Mahn for his Hands-On Courses at the 8th Dental Facial Cosmetic Int'l Conference! 01-07 Nov 2016 | Jumeirah Beach Hotel, Dubai, UAE