(References for articles usually start with the author and then the title, plus other specific information to locate the article. I have not followed this format. I put the title first and the year last.)

1. As an introduction to prosthodontic literature I posed the question, how did the phrase, "Place the labial surface of the maxillary central incisors 8-10 mm in front of the center of the incisive papilla" evolve?

The Incisive Papilla. Harper, Robert N. J Dent Res 27:661-668, 1948.
Before this article the incisive papilla was simply considered as a protective covering for the incisive foramen. By considering preextraction and postresorption models of the same case, Harper concluded that there is no change in the position or dimensions of the papilla from the dentate stage to the edentulous stage.
He also discovered that the papilla cannot be depended upon as a guide in marking the midline in edentulous cases. In only 58% of the cases was the center of the papilla lined up with the center of the face. One of his conclusions was that the incisive papilla is a dependable basis for a technique designed to reproduce the horizontal and vertical position of the maxillary central incisor. (Today we use the papilla to determine the horizontal position of the maxillary central incisor.) He didn't give the number of cases that he used in his study.
Harper also related the center of the incisive papilla to the canines. He drew a line from the center of the incisive papilla to the canines. He felt that if the line passed within the anterior half of the canines, the anterior arch will have a normal contour and when it passes through the distal half of the canine, then the arch will be flat. (See the review of Dr. Schiffman's article.)

Tooth placement and base contour in denture construction. McGee, G.F. J Prosthet Dent 10:651-657, 1960.
McGee notes that the incisive papilla remains in a constant position after tooth loss. The lingual surface of natural maxillary central incisors touch the incisive papilla or is just anterior to it. The bucco-lingual measurement of the maxillary centrals ranged from 6.8 mm to 8.6 mm with an average of 7.7 mm. Since the centrals are slightly anterior to the center of the incisive papilla he used 8 mm as the position of the labial surface for the average patient. "This position may be altered in an anterior or posterior direction to meet the requirements of the individual patient."
He also mentions that the upper six anterior teeth not only position the upper lip, but their incisal edges position the lower lip by making contact with the lingual half of its vermilion border in both rest and occluded positions.

Designing Complete Dentures, Watt, M.D. Philadelphia 1976. W.B. Saunders Co.
In his textbook Watt stated that "The average distance from the middle of the incisive papilla to the middle of the labial surface of the upper central incisor is approximately 10 mm; it is seldom less than 8 mm."

Relationship of the incisive papilla to the maxillary central incisors. Ortman, H.R. and Tsao, D.H. J Prosthet Dent 42(5):492-496, Nov 1979.
This article looks like the answer to our question. Actually it doesn't. I don't even recommend reading it unless you want to see the simple made complicated.
I should quickly point out that the measurements are made from the most posterior point of the incisive papilla instead of the center. To be sure the "center" would be an educated guess. Guesses are hard to justify if you are measuring (as this author did) to a thousandth of a millimeter. There were 38 models in the sample.
The average distance between the most anterior point of the maxillary central incisors and the most posterior point of the incisive papilla was 12.454 mm with a standard deviation of 3.867 mm. This distance was measured when these two points were projected on a plane parallel to the reference plane formed by the tips of three symmetrically located interdental papillae.
This will make sense if you read the article a few times.

Relation of the maxillary canines to the incisive papilla. Schiffman, P. J Prosthet Dent 14:469-472, 1964. A line drawn through the center of the papilla out to the canines, passed through the cusp tips 78% of the time. If you included an area of 1 mm anterior and 1 mm posterior to the center of the papilla you crossed the canine cusps 92% of the time.

Effects of complete dentures on facial esthetics. Martone, A.L. J Prosthet Dent 14:231-255, 1964.
Concerned with many aspects of restoring natural facial contours on a wide range of patients after the loss of teeth--only one of which is the placement of the maxillary centrals anterior to the incisive papilla.
In one example, placing the centrals 4 mm anterior to the incisive papilla "augmented the senile appearance of the face as a whole." The author gave no examples of placing centrals more than 10 mm in front of the incisive papilla.
Also discusses the negative aspects on the remaining tissues (muscles, nerves) when improper placement of the teeth (such as opening the vertical) takes place.

Temporary elimination of gag reflex for dental procedures. Friedman, M.H., Weintraub, M.I. J Prosthet Dent 73:319, 1995
This is the tip to put salt on the tongue. "The gag reflex is extinguished by a superimposed simultaneous stimulation of the chorda tympani branches to the taste buds in the anterior two-thirds of the tongue."

Making an impression of a maxillary edentulous patient with gag reflex by pressing caves. Xianyun, R. J Prosthet Dent 78:533, 1997.
Acupuncture caves are sensitive points in the human body that feel soreness and distention ("Suan Zhang") when the acupuncture needle is entered. Specific points on the hand or wrist are compressed with your thumb for 5 to 20 minutes to produce this feeling of soreness and distention.
I suppose this works because of simultaneous stimulation which results in the extinction of the gag reflex. (This should only be used on a select group of patients in your private practice.)

Posterior palatal seal location and preparation on the maxillary complete denture cast. Calomeni, A.A., et al. J Prosthet Dent 49(5):628-630, 1983.
The authors talk about locating the "ah" line by noting the junction of the movable and immovable parts of the palate.
The anterior line is located by noting where the displaceable (soft) tissue is in front of the posterior ("ah") line.
Ink is used to mark the lines. I personally find the lines to be messy. Certainly a good article to read.

Vertical relation of the occlusion by the patient's neuromuscular perception. Lytle, R. J Prosthet Dent 14:12-21, Jan-Feb 1964.

Vertical dimension literature review. Swerdlow, H. J Prosthet Dent 15:241-247, Mar-Apr 1965.

Evaluation of articulators, Part I - Basic concepts. Weinberg, L.A. J Prosthet Dent 13:622, 1963.

Evaluation of articulators, Part II - Arbitrary, positional, readjustable. Weinberg, L.A. J Prosthet Dent 13:645, 1963.

Face form guide in maxillary central incisor. Mavroskoufis, F. Ritchie, G.M. J Prosthet Dent 43(5):501-505, 1980.
("...no similarity between face-form and incisor tooth form.")

Applying harmony in selecting and arranging teeth. Pound E. Dent Clin North Am. 241-258, March 1962.
He relates the outline form of the face to the outline form of the teeth. See previous reference.

Selecting the anterior tooth mould. Young, H.A. J Prosthet Dent 4:748-760, 1954.

Dental esthetics and golden proportion. Levin, E.I. J Prosthet Dent 40:244, 1978.

The principles of vision perception and their clinical application to denture esthetics. Lombardi, R.E. J Prosthet Dent 29:358-383, 1973.

An introduction to denture simplification: Phase II. Pound, E., Murrell, G.A. J Prosthet Dent 29:598-607, June 1973.

Complete denture occlusion. Ortman, H.R. Dent Clin North Am 21 (2):299-320, Apr 1977.
If you read this article and somehow it seems familiar don't be surprised. Dr. Sheldon Winkler was the editor of this edition of Dental Clinics of North America. He used the articles in this edition as a format for his text on complete dentures.

©1999 by Julius Rosen, D.D.S.