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tion using “s” sounds as well; however, whereas this certainly is an important consideration, the
“s” sound is the result of the interaction between the maxillary and mandibular incisors. 12 In the
Esthetics—Function—Structure—Biology treatment planning protocol, we first position the maxillary
incisors to the ideal esthetic position and then modify the mandibular incisors and the lingual aspect
of the maxillary incisors to correct the “s” sound, the final position and shape being determined
by the movement of the mandible during speech. Enunciation of “f” and “v” sounds creates light
contact of the central incisors with the “wet-dry” line of the lower lip. Dimpling or trapping of the
lower lip signals that the contact impingement by the teeth is too great and indicates teeth that are too
long and must be shortened. One difficulty in using “f” and “v” sounds to evaluate length and position
is that they can tell the dentist reliably whether the teeth are too long, but they do not offer much
insight into whether the teeth are too short. Even when the maxillary central incisors are severely worn,
formation of “f” and “v” sounds will look correct because speech is so adaptable to shortening of the
maxillary incisors. Because restorative dentistry usually is involved in lengthening maxillary
central incisors, using phonetics is an excellent consideration in determining whether teeth have been
lengthened too much.
■ Conclusion
The focus of this article is the esthetic considerations of the maxillary central incisal edge as part of
the Esthetics—Function—Structure—Biology process of diagnosis. Clinicians should recognize that all
changes made to the position of the maxillary central incisor must address the functional etiology that
placed the central incisor in a position other than one that creates the ideal smile. They also must understand
clearly how the functional component, the occlusion, must be altered to produce a predictable
result with the new incisal edge position.
In this article, I have presented three considerations in evaluation and positioning of the maxillary central
incisal edge. Given the importance of esthetic success in practice today, and the fact that every facet
of treatment is affected when a dentist decides to change a patient’s incisal edge position, it is critical
that dentists learn, become comfortable with and use these techniques when evaluating patients. CM
Dr. Frank Spear is founder and director of Spear Education. To learn about Dr. Spear or Spear Education, visit speareducation.com or call 866-
781-0072.
DISCLOSURE: Dr. Spear did not report any disclosures. The views expressed are those of the author and do not necessarily reflect the opinions
or official policies of the American Dental Association.
■ References
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6. Frush JP, Fisher RD. The dynesthetic interpretation of the dentogenic concept. J Prosthet Dent 1958;8(4):558-581.
7. Lombardi RE. The principles of visual perception and their clinical application to denture esthetics. J Prosthet Dent 1973;29(4):358-382.
8. Lombardi RE. A method for the classification of errors in dental esthetics. J Prosthet Dent 1974;32(5):501-513.
9. Pound E. Esthetic dentures and their phonetic values. J Prosthet Dent 1951;1(1-2):98-111.
10. Watt DM. Tooth positions on complete dentures. J Dent 1978;6(2):147-160.
11. Pound E. Recapturing esthetic tooth position in the edentulous patient. JADA 1957;55(2):181-191.
12. Rothman R. Phonetic considerations in denture prosthetics. J Prosthet Dent 1961;11(2):215-223.
Reprinted with permission from the American Dental Association (ADA): Spear FS. Too much tooth, not enough tooth: making decisions about
anterior tooth position. JADA 2010;141(1):93-96. Copyright ©2010 American Dental Association. All rights reserved. The American Dental Association
makes no representation and accepts no responsibility for the accuracy, timeliness or comprehensiveness of the cover image.
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