The Aesthetic Edge A New Approach to Smile Design

Dentists who are experienced with cosmetic treatment know that subtle variations in the shapes of the teeth can mean the difference between successful treatment and hours of reshaping, contouring, shortening, or worst of all, restarting a case. To minimize extended or failed delivery visits with removable or fixed prosthetics because of patient dissatisfaction with the smile design, several smile guides have been developed over the years. These guides have attempted to serve as a communication tool to help the doctor understand what the patient wants, and for the doctor to communicate those desires to the laboratory.

The first smile guides were printed manuals showing various smile designs. Some authors used personally preferred shaped teeth to demonstrate various designs, while others catalogued the designs based on sequentially changing the incisal line angles of the anterior teeth. To demonstrate these shapes, some authors restored each design on a single patient, while others selected different individual natural smiles to show each design. Some printed these designs in manuals showing only close-up views of the smiles, while other manuals were printed with only portrait views of each design.

As the popularity of cosmetic imaging programs increased, some of these guides evolved into digital form to act as digital smile libraries. However, until now, no smile guide had been developed specifically to show the aesthetic effects of the subtle variations in incisal line angle while simultaneously incorporating the requirements of cosmetic imaging programs.

DESIGNING SMILES

Let’s first examine the dynamics of the smile. The lower ten teeth in the aesthetic zone have only one good option: straight, even, and white. Of the ten teeth in the upper aesthetic zone, the four bicuspids can be considered to have one universal aesthetic shape: a rounded point. This leaves the variations for aesthetic smile design strictly to the six upper anterior teeth.

There are three shapes of central and lateral incisors based on the shape of the incisal line angles: square, square-round, and round. There are also three shapes of the cuspids: pointed, round, and flat. All possible combinations of these teeth would result in twenty-seven smile designs. We can, however, eliminate those designs that result in the lateral incisor being more “square” than the central incisor. It has been my experience that these designs simply do not look good. The remaining aesthetic combinations make up the eighteen basic smile designs. There can be variations of these basic designs such as shorter or longer centrals or laterals, and narrower or greater angles of the incisal embrasures. Variation in the incisal contour (the shape of the incisal edge of each tooth) such as flat, round, or characterized can also be considered.¹ Each variation of a basic smile design can be easily discussed with the patient, drawn onto copies of the basic design, or computer imaged. The final choice constitutes the “aesthetic incisal edge”.

CLINICAL TECHNIQUE

Figure 1. Before treatment, full face.	Figure 2. Before treatment, retracted close up.
Figure 3. Before treatment, left profile.	Figure 4. Digital radiograph showing interproximal fillings.

The perception of a beautiful smile is created by the combined appearance of the face, lips, gums, and teeth. Because we want our patients to consider only the effects of the shape of the teeth on aesthetics, all other variables need to be eliminated.² A simple method to eliminate all variables other than the shape of the teeth is to create all smile designs on a single individual. To accomplish this, a patient in need of a full smile makeover was selected (Figures 1 and 2). Following two orthodontic treatments, once as a teenager and again as a young adult, she still had an open bite (Figure 3). In addition, her teeth were riddled with numerous interproximal fillings (Figure 4). From her preoperative impressions we did a wax-up of her anticipated treatment, duplicated this in stone, and made prep guides and hard/soft matrices for transitionals.

Anesthesia was administered. The teeth were prepared for twenty porcelain veneers using the Shofu Contemporary Cutting Kit. The peripheral margins were outlined using the round diamond (Figure 5). A depth cutter was used to score the facial to facilitate rapid removal of old composite and some enamel. The coarse round-end tapered diamond did the bulk reduction. The preparation walls and margins were simultaneously finished using the super-fine, round-end tapered diamond.³

Figure 5. Round diamond outlines periphery of preparations.	Figure 6. Bident removes excess and inflamed tissue effortlessly.

The Bident Bipolar electrosurgery device performed a bloodless “gum lift” to create gingival harmony around the lateral incisors (Figure 6). Excess gingival tissue was easily removed on the facial. Inflamed interproximal tissue was excised for clean margins and impressions.

Figure 7. Hard/soft matrices are placed with dual cure bis-acrylic temporary material. The matrix is removed.	Figure 8. Applying Gentle Gel to tissue.

Figure 9. Maxillary and mandibular temporaries.

Upon completion of tooth preparation, final impressions and bite registrations were taken. The hard/soft matrices were filled with auto cure bis-acrylic and seated over the prepared teeth to create the temporaries (Figure 7). After the outer matrix was removed first, the soft matrix was removed to reveal a smooth, polished surface. The margins of the temporaries were finished with fine finishing diamonds from the Shofu Contemporary Finishing Kit. Gentle Gel (Bident), a soothing salve containing aloe vera, tea tree oil, and Vitamin E, was applied to the soft tissues to further promote healing (Figure 8). The resulting provisionals were beautiful and durable (Figure 9).

CEMENTATION AND PHOTOGRAPHY

The laboratory constructed eighteen sets of veneers corresponding to the basic smile designs determined by our earlier analysis. The veneers were organized according to tooth shape, creating the blueprint for placing each veneer for each design with as few steps as possible.

Digital photography was chosen because of its inherent ease of use for layout design of our intended printed Smile Style Guide, and to facilitate the digital qualities needed to use the photos in cosmetic imaging programs.

The temporaries were scored and popped off with a spoon excavator. Each set of veneers were placed with try-in paste, cleaned, and photographed. Seven views were completed for each design before moving on to the next. These included portrait, close-up smile, lateral smile, and four anterior retracted views.

The patient began to choose her preferred smile design from the resulting eighteen choices. After much deliberation, she narrowed her decision to two, but could not make up her mind between these two choices. Interestingly enough, it was the profile view that made the final decision easier. This is significant because it shows the importance of the lateral shot. This “social angle” is the view from which other people view the patient. No other library contains this. The patient’s chosen set was bonded into place. To complete the case, the margins and occlusion were adjusted and polished with the Shofu Contemporary Finishing Kit.

RESULTS

Figure 10. Lateral smile; Lorin Library shape tab LL18.

The case selection, laboratory specifications, digital photography, and photo compositions were all carefully planned to fulfill the needs of both a printed smile guide and a digital smile library. The printed smile guide needed to be capable of helping the patient and doctor towards selecting the preferred aesthetic design. The guide needed to show the entire aesthetic complex, and was therefore printed in full color with each of the 18 designs being shown in portrait, close-up smile, and lateral views. The guide was arranged to create a three-step smile selection process, beginning with selection of the cuspid shape from the lateral view. This lateral view is how observers often view the patient’s smile, yet the patient rarely sees themself from this angle (Figure 10). As we found with our model, this is a very important step.⁴

Figure 11. Smile; Lorin Library shape tab LL01.	Figure 12.
Figure 13.	Figure 14.
Figure 15. Figures 12 through 15. LL12 with four varying incisor length options.	Figure 16. Portrait; Lorin Library shape tab LL01.

Step 2 is the selection of the shape of the four incisors from the close-up smile view (Figure 11). Step 3 is the selection of the relative incisal edge length from the four variations presented (Figures 12 through 15). Upon completion of the smile selection process the patient can confirm their choice by seeing how the smile looks on the corresponding full portrait, which is printed on the adjacent page to the side and close-up views (Figure 16). This smile guide is unique because it shows all designs on a single face (minimizing aesthetic variables) and includes lateral smile views.

Because the model for the smiles was a young attractive woman, many of our patients who do not share these qualities (different gender, age, or ethnicity) may have difficulty imagining how the chosen smile might look on them. This is where the power of imaging comes into play.⁵

Figure 17. Lorin Library shape tab LL01 open occlusion, flat arch digital image.	Figure 18. LL14 closed occlusion, curved arch digital image.

Once the smile design is selected from the printed guide, the corresponding digital smile can be used for cosmetic imaging. The digital smile library enables imagers to simply drag-and-drop a new smile into their patient’s portrait images. If a digital smile library only provides a single retracted version of each smile design, to use these images effectively it is required that the initial portrait photo be captured at precisely the same angle as the library image. This is highly unlikely and often results in a poor simulation. The key to successful “smile transfer” imaging with library smiles is to have the library images include the arch posteriorly all the way to the molars, and include four specific versions of each retracted design. The four versions compensate for the two ways in which patients smile (with their teeth slightly parted or with their teeth together), and for the variation in incisal-occlusal plane (the plane can be straight or curved depending on the patient’s anatomy and the angle from which the photo was taken) (Figures 17 and 18).

DISCUSSION

A Smile Style Shape Guide offers major benefits, with or without imaging. The most straightforward use of a smile library is simply to guide the patient in choosing their favorite smile. If they request modifications of an existing library smile, a black and white photocopy of the design that is the closest to the patient’s desires can be made. Drawn-in changes can act as a crude simulation showing variations in incisal edge length, incisal edge contour, and preferred depth of incisal embrasure shape.⁶ The drawing can confirm what the patient is trying to communicate, and can be sent to the lab as a blueprint for wax-up or final restoration.

For offices with cosmetic imaging, the library has even greater benefits. Use the guide as described above. Then use the corresponding digital image to create a simulation of the chosen smile as it would appear on the patient’s portrait. For greater diversity, the library of digital photos discussed in this paper has been formatted to work with any cosmetic imaging program capable of importing smiles into portraits. You can use the image to drag-and-drop the entire smile into the patient’s portrait in one step. Depending on the capabilities of the imaging software, the digital photos can be segmented into sections of the arch or into individual teeth. These segments can then be used in more diagnostic imaging techniques such as tooth-by-tooth imaging.

When used with the Digital Dentist imaging system the digital images have been preformatted for segment imaging. You can use the digital photos for full smile transfers (image the entire smile in one step), or to image your cases one tooth at a time to create a diagnostic-quality simulation.

CONCLUSION

It is difficult, time consuming, and psychologically challenging to meet the demands of anterior dentistry. Comprehensive cosmetic treatment requires a systematic approach to combining the various factors that create a smile. Excellent aesthetics cannot be achieved without excellent communication between the patient, the dentist, and the laboratory. The use of a shape guide is therefore an essential tool for treatment management, from case acceptance to patient satisfaction.⁷

Figure 19. Final Portrait.

An ideal smile guide should be useful for both smile shape selection and cosmetic imaging. The combination of the printed smile style guide and digital photo CD as discussed in this paper has been collectively named the Lorin Library. These tools give the practitioner the ability to define the elements of aesthetic choices and to select, design, communicate, and deliver appropriate treatment. The use of a smile style shape guide can make both fixed porcelain and removable dental treatment more predictable, more successful, and most of all, more fun (Figure 19)!

References

1. Hornbrook D. Communication: the key to aesthetic success. Profiles in Dentistry. 1999;2:6-7.

2. Crispin B. Contemporary Esthetic Dentistry: Practice Fundamentals. Carol Stream, Ill: Quintessence Publishing; 1994.

3. Berland L. The Latest & Greatest in Cosmetic Dentistry- A Full Mouth Rehab in Two Appointments. Dallas, Tex: LB Productions; 2001.

4. Dunn WJ, Murchison DF, Broome JC. Esthetics: patient’s perceptions of dental attractiveness. J Prosthodont. 1996;5:166-171

5. Berland L. Digital Art helps patients accept treatment. Dent Pract Report. 2000;6:22-25.

6. Kirtley GE. The Interrelationship of oralfacial complex and its effect on Smile Design. Contemp Esthetic Restorative Pract. 1999;10:72-78.

7. Anderson KM. Components of an Esthetic Smile [master’s thesis]. Dallas, Tex: Baylor College of Dentistry; 2002.

Dr. Berland is both accredited and a fellow of the American Academy of Cosmetic Dentistry. He is one of the most sought after speakers and published authors on cosmetic dentistry in America. He has been featured in national and regional magazines, major dental journals, and recently NBC News, Fox News, and ABC’s 20/20. For more information on Digital Practice Builder—A Digital Imaging and Smile Design Seminar, or any of Dr. Berland’s seminars, call (214) 999-0110 or contact www.dallasdentalspa.com.

Disclosure: Dr. Berland is the developer of the Lorin Library.

Dr. Traub has spoken and published on numerous occasions on the incorporation of digital imaging technology into the dental practice.

Disclosure: Dr. Traub is the founder of Digident and the developer of the Digital Dentist Cosmetic Imaging System.

Dr. Williams practices in Dallas, Texas with Dr. Berland. She is codirector of the Dallas Imaging Mini Residency and the Hands-on One Appointment Inlay/Onlay Seminar.