Variations in facial relationships; their significance in treatment and prognosis.

Abstract What constitutes harmony and balance of the component parts of the face, namely: the skeletal framework, the denture, and the overlying musculature, has for many years commanded the attention of the research investigator, the teacher, and the clinician. A satisfactory solution is most difficult to attain, one being faced with the innumerable variations of type, as well as the unfolding of the facial pattern from the infant to the adult. The results of this study of twenty individuals with excellent occlusions and a review of similar investigations appear to warrant the following conclusions: 1. (1) There is a facial pattern that represents mean or average form for individuals possessing excellent occlusions. 2. (2) There is a notable deviation on both sides of the mean findings of the facial pattern. These represent the usual variation one must reckon with when appraising balance and harmony. 3. (3) Excessive deviations of the means and extremes found in this study usually express abnormalities of relationship which will be evident as disharmonies or imbalance of particular areas. 4. (4) The skeletal pattern in the lateral aspect may be described in figures and be appraised as good or bad according to the amount of deviation of the readings from the known mean pattern. Such information can be of considerable help in forming a prognosis of treatment. 5. (5) The relationship of the denture of any case to its skeletal pattern can likewise be compared with known relationships of good balance and harmony. Such analysis tends to point out the desirable tooth movement indicated in treatment. 6. (6) Serial study of cases by this method permits definite expression of anteroposterior and vertical changes induced by treatment and those occurring during retention, as well as those changes that may be attributed to growth and development. 7. (7) This method of cephalometric analysis has been tested for three years in the author's practice as well as in the graduate department of orthodontics at the University of Illinois. In the last year the orthodontics departments of the University of California, Northwestern, and Indiana have cooperated in testing its clinical and teaching value. Out of these experiences has come one particularly important comment: The ten figures used in the appraisal do describe skeletal and denture relationships but single readings are not so important; what counts is the manner in which they all fit together and their correlation with type, function, and, esthetics.