1500 Summer Street, Stamford, CT 06905
(203) 883-4433
1500 Summer Street, Stamford, CT 06905
(203) 883-4433
The ratio of Golden Proportion, 1 to .618, can be found in a remarkable number of places and plays a huge role in both modern and historical structures and forms. The earliest references to Golden Proportion date back at least 2,500 years but cannot be traced to a particular event or originator. It is the underlying proportion of Egypt’s Pyramids, the Parthenon in Rome, and was central element in Plato’s Timaeus which was one of the earliest texts to document the physics of the cosmos. In the 14th Century Leonardo Da Vinci first coined the term “Divine Proportion” and it severed a central role in the drawing of figures in numerous great arts works including “The Last Supper.”[1] In the hundreds of years that past observations of “Divine Proportion,” later known as Golden Proportion were identified and documented in all aspects of life, from the designs on butterflies [Figure 1:Buter.jpg Caption: “Golden Proportion in Nature”] to the proportion of teeth. Perhaps the most interesting work is that of Dr. Stephen Marquardt, an oral and maxillofacial surgeon, who developed the Marquardt Beauty Mask which can successfully identify beauty across all races, cultures and areas. [figure 2:beautymask.jpg Caption “Marquardt Beauty Mask”]
When applied to dentistry “Golden Proportion” states that the teeth look most harmonious when viewed from the front if the amount of visible tooth surface of the centrals to laterals forms a ratio of 1.6 to 1.0. [Figure 3: Proteeth.jpg Caption: “Ratio of Central to Laterals is 1.6 to 1.0”]
One of the more difficult cosmetic cases is a case where, in addition to teeth that are crooked and dark, the teeth are disproportionately sized. Such was the case of a 25 year old female patient of mine who always hated her smile. As a child she had orthodontic treatment to straighten her teeth but the crowding returned as a young adult. The figure shows the severe crowding in the upper anterior segment which has forced her laterals, especially #7, out of the arch.[Figure 4:Crowding.jpg Caption: “Crowding in Upper Anterior”] In addition her centrals are disproportionately large compared to her laterals creating a “buck tooth” appearance which was equally if not more bothersome to the patient. [Figure 5: dispro.jpg Caption: “Visible Tooth Ratio of 1.85 to 1.0”] The current ratio of visible tooth structure between the central and laterals is 1 to 1.85.
The treatment objective of this case is to create a both an aesthetically pleasing and bio-mechanically correct smile. To explore treatment options preoperative study models were altered by narrowing the centrals and both moving and widening the laterals. [Figure 6:alteredmodel.jpg Caption: “Study Model For Patient Presentation”] The models were presented to the patient and extremely well received by the patient.
The next step was to determine the path to these ideal treatment results. The theoretical options were more orthodontic treatment and porcelain veneers. Orthodontics would require the extraction of teeth to create more arch space to fit all of the teeth. However this would not improve the proportion of the teeth, which was one of the patient’s main concerns. Due to failure to meet all essential criteria and the time and inconvenience of orthodontics this treatment plan was rejected.
An alternative was to prepare porcelain veneers for eight upper teeth, from first premolar to first premolar. This would allow us to refine all of the visible upper front teeth and create a matching size, shape and shade. Due to budget limitations and interest in the most conservative possible approach, in so far as no extractions and preparation of the minimal number of teeth, a treatment plan preparing only the four incisors was requested. The other teeth would be bleached with in office ZOOM (Discus Dental) to allow us to whiten the patient’s teeth to closely approximate the four new veneers. Since her teeth were in a yellow cast and a shade of A2 at only 25 yeas old we targeted a final share of B1 or lighter.
The preparation phase required narrowing the centrals and creating room for the laterals to bring the teeth closer to a golden proportion ratio. This is much more aggressive than traditional conservative veneer preparations, but critical to achieving the case objectives. The sub-gingival portion of the teeth needed to be prepared first to physically narrow the teeth. The contact areas would need to be opened and the necks of the central incisors would need to be narrowed to ensure that the resulting final veneers could be made smaller to fit Golden Proportion. After the sub-gingival areas were prepared and the gingival embrasures were opened, the supra-gingival areas were prepared. [Figure 7: prep(center, left, right.jpg) Caption: “Prepared teeth”
Figure 7 shows the preparations and you can see the embrasure space that was created. The basic preparations were done with a Diamant 856-021-9 MLX and then the inter-radiculer root space was opened with very small and narrow Diamant 132-008 F, 132-008 EF and 132-008 UF. These come in a series of fine, very fine and ultra fine that are used sequentially to narrow the root and then to create a smooth root surface that will not be covered by the final veneer. Figure 8 shows the final Feldspathic veneers from DaVinvi Dental Laboratories on the model placed on top of the Panadent Golden Proportion guide. [Figure 8: veneergp.jpg: Caption: “Final Veneers on Golden Proportion Guide”]
Figures 8, 9 and 10 show the final results. [Figure: Beforefull.jpg Caption “Robin Prior to Treatment” Figure:Afterfull.jpg Caption: “Completed Case” Figure: Afterclose.jpg Caption: “Completed Veneers” Note the natural look regarding both the straight alignment and proper proportion to both her arch and the rest of her facial features. It is exciting to see the dramatic results from a relatively conservative technique of preparing just 4 teeth.
Many dental patients are unhappy with their smile but believe a beautiful smile is outside their budget. The first step is to listen to the patient to understand what their primary concerns are. The second step is carefully examine and analyze the case to develop a treatment plan that will give the patient the greatest degree of what they want within the context their constraints, be them financial or otherwise. Remember dentistry doesn’t end when the last veneer is placed or the last bill is paid. The final step is to maintain a strong relationship with your patients to ensure good oral hygiene and restorations that are long lasting as they are beautiful.
[1] The Divine Proportion : A Study in Mathematical Beauty by H. E. Huntley