Abstract: This case of an adult male patient with missing maxillary lateral incisors who was unhappy with his smile focuses on implementation of the digital smile design (DSD) concept(Fig 1 &2).Combined with the use of a dento-facial analyzer, DSD, which employs a series of extraoral photographs, allowed the clinician to preoperatively plan different approaches to the treatment and visualize the outcome of each one, as well as to effectively communicate critical tooth position references to the laboratory technician and the patient. The additive approach used in this case minimized tooth preparation while creating an esthetic smile.
Phase 1: Diagnosis and Treatment Plan
The standard DSD protocol requires the following four extraoral photographs to be taken: retracted view, smile view, lateral view, and 12 o’clock view.1 The first step in this case was to superimpose the facial midline and interpupillary lines on the photographs of the full-face smile (Fig.3) and then on the retracted close-up smile (Fig. 4).
To create harmonious tooth widths and keep the dental midline coincident with the facial midline, aggressive tooth preparation involving endodontics and a post/core restoration would be required. The digital treatment plan allowed the patient to visualize and understand the compromises that a restorative-only approach would induce. He could see that the midline of the final restoration would be positioned about 2 mm offset from the facial midline, and he agreed to the placement of the midline slightly to the left of the facial midline in order to avoid orthodontic treatment(Fig. 5).2
Smile design begins with determining the upper incisal edge position, as proposed by Spear and Kois.3,4 Tooth size, tooth proportion, and gingival contours are then designed in sequential steps once the digital ruler is calibrated (Fig 6 &7). The width determined for this patient’s central incisor was 9.5 mm, which is within the norm for central incisor dimensions.The next step was to determine the upper incisor position in relation to the lower lip, using the lateral smile view and 12 o’clock view (Fig.8) photographs. The upper incisor position is recommended to be at the vermillion border of the lower lip.5 In this case, it was decided that the new incisor edge would be positioned 1.5 mm facially from the preoperative position.
Phase 2: Transfer of Digital Wax-Up to Master Cast
A dento-facial analyzer was used to record and then communicate the essential functional and esthetic parameters for mounting the maxillary cast (Fig.9). The combination of the DSD and the dento-facial analyzer system enabled the clinician to effectively communicate the proposed midline and maxillary occlusal plane—critical tooth position references—to the laboratory technician.
When placed on the articulator, the platform ensured the symmetry of the incisal edges, as well as the horizontal and vertical tooth positions (Figure 10). The platform can be lowered or raised as needed to allow for more or less incisal length. The use of an index tray provided an easy reference for the wax-up fabrication (Fig.11& 12). The reference platform on the articulator was used to determine the width, length, and facial position of the maxillary central incisor.
Phase 3: Intraoral Evaluation
Temporization material (ProtempTM, 3M ESPE) was injected into the silicone index and applied intraorally without any tooth preparation. The esthetics, phonetics, functional outcome, lip support, and facial harmony were evaluated at this time6,7. The final treatment plan was initiated after the patient’s approval of the intraoral mock-up (Fig.13).
Phase 4: Surgical Treatment
A stent was fabricated from the wax-up and placed intraorally to provide guidance for both the periodontal surgery and tooth preparation. Clinical crown lengthening was performed on teeth Nos. 8 and 9. Bone sounding was done, and Er:Cr:YSGG laser therapy (WaterLase, Biolase) was used to recontour the gingiva (Fig.14).
Phase 5: Definitive Restorations
Two months after the periodontal surgery, the patient returned for the final restorations. The silicone index of the diagnostic wax-up was now used as a guide to minimize the amount of tooth reduction. Based on the silicone index, the central incisors were planned to have 1 mm of facial volume added and a 0.3-mm chamfer.
Conclusion:This case illustrates a method to systematically diagnose, plan, and stage treatment for a smile makeover. The use of the DSD allowed the clinician to preoperatively plan various approaches to the treatment and visualize the outcome of each approach. The use of the Kois Dento-Facial Analyzer simplified the wax-up and improved accuracy. The new veneers harmonize with the face and lower lip, and the spaces were perfectly closed (Fig.15 &16). The additive approach minimized tooth preparation and also made the teeth more prominent in the patient’s smile. The tissue is expected to mature with interdental papillary rebound. The patient was satisfied with not only the excellent esthetics but also the minimal tooth structure removal.
1. Coachman C, Van Dooren E, Gürel G, et al. Smile design: from digital treatment planning to clinical reality. In: Cohen M, ed. Interdisciplinary Treatment Planning, Vol II, Comprehensive Case Studies. Chicago, IL: Quintessence Publishing; 2012:119-17
2. Kokich VO, Kiyak HA, Shapiro, PA. Comparing the perception of dentists and lay people to altered dental aesthetic. J Esthet Dent. 1999;11(6):311-324.
3. Spear FM. The maxillary central incisor edge: a key to esthetic and functional treatment planning. Compend Contin Educ Dent. 1999;20(6):512-516.
4. Kois JC. Diagnostically driven interdisciplinary treatment planning. Seattle Study Club J. 2002;6(4):28-34.
5. Small BW. Location of incisal edge position for esthetic restorative dentistry. Gen Dent. 2000;48(4):396-397.
6. Magne P, Belser U. Bonded Porcelain Restorations in Anterior Denti- tion: A Biomimetic Approach. Chicago, IL: Quintessence Publishing; 2002.
7. Kois JC. Altering gingival levels: The restorative connection. Part I: biologic variables. J Esthet Dent. 1994;6(1):3-9.