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Dental Proportions

teeth smile design golden proportion
The dark space between the corners of the mouth and the outer surface of the canines during a smile (red line 1.0) is called negative space. The "negative space", also called "buccal corridor", approximates a Golden Proportion with the distance of the dental midline to the outline of the canine (red line 1.618).

The width of the central incisor is in golden proportion to the width of the lateral incisor (as seen from the front), which in turn is in golden proportion to the part of the canine that is visible from the front. The width ratios among the upper front teeth have been described as Golden Proportions, which is described in more detail on this page. They are just a point of reference for the diagnosis, treatment planning, and communication of cosmetic dentistry cases.

Even though the negative space escapes the attention of a layman, it cannot be ignored. It creates a balance between the cohesive and segregative forces of a smile and provides a harmonious relationship between the smile and other facial features. This example underlines that some important elements of facial harmony are more easily perceived than others. However, they all need to be understood by the cosmetic dentist and the dental laboratory.

The presence of a lateral negative space gives depth and mystery to a smile, while its absence displays exuberance and brilliance paired with functional disturbances. Many patients have come to Dr. Rabanus to widen their dental arches and to partially obliterate the dark area between the side teeth and the inner corners of the lips. This is easily attained by placing porcelain veneers on the buccal aspects of the teeth behind the canines. However, this is not always possible nor advisable for every patient and depends on his general dental condition and oral and masticatory function.

It should be emphasized that dimensional attributes such as Golden Proportions are used to refine the observational skills of a cosmetic dentist. It is by no means a rigid rule. However, the appraisal of a smile understanding the significance of a Golden Proportion refines an understanding of what "natural" design often coincides with. Aesthetic principles merely serve to better appraise the relationship between objects that differ from each other by form, dimension, and contrast. Combined together they create a picture that contains cohesive and segregative forces.

Our perception varies depending on the viewpoint that we establish. Simply being aware of aesthetic principles, such as cohesive and segregative forces, symmetry, Golden Proportion, balance, and domincance sharpens the view of any professional who attempts to recreate natural appearance. This includes the cosmetic dentist.

Evidently, the genetic code does not care about aesthetic principles when intitiating and executing the formation of biological tissue. The prime directive of any genetic code is to integrate the biolgical organism with all its individual structures into the physical environment in which it exists. The biological entity cannot be appraised without the context within the physical demands of its environment. This, in a way, could be considered the principle of a holistic viewpoint.

The mastictory system of a mammal is especially fine tuned to the strict requirements of the physical universe that surround us. Throughout evolution, it has adapted to varying qualities of the environment. From being a primitive filtering organ millions of years ago to a finely-tuned chewing apparatus with meticulous sensory capabilities, it is also the primary social organ of a human being. It communicates and displays the state of health of an individual, which is consciously appraised by his or her fellow human beings. It embodies an indispensible prerequisite for human relationship. Hence, cosmetic dentistry has an important impact for the lives of many. It is deeply engrained in our culture.

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