THE CHANGING GOALS OF
ORTHODONTIC TREATMENT
Crowded, irregular, and protruding teeth have been a
problem for some individuals since antiquity, and attempts
to correct this disorder go back at least to 1000
BC. Primitive (and surprisingly well designed) orthodontic
appliances have been found in both Greek and E t r uscan
materials. 1 As dentistry developed in the eighteenth
and nineteenth centuries, a number of devices for the
"regulation" of the teeth were described by various authors
and apparently used sporadically by the dentists of
that era.
After 1850, the first texts that systematically described
orthodontics appeared, the most notable being
Norman Kingsley's Oral Deformities. 2 "Kingsley (Figure 1-
1), who had a tremendous influence on American dentistry
in the latter half of the nineteenth century, was
among the first to use extraoral force to correct protruding
teeth. be was also a pioneer in the treatment of cleft
palate and related problems.
Despite the contributions of Kingsley and his contemporaries,
their emphasis in orthodontics remained the
alignment of the teeth and the correction of facial proportions.
Little attention was paid to the dental occlusion, and
since it was common practice to remove teeth for many
dental problems, extractions for crowding or malalignment
were frequent. In an era when an intact dentition was a rarity,
the details of occlusal relationships were considered
unimportant.
In order to make good prosthetic replacement teeth,
it was necessary to develop a concept of occlusion, and
this occurred in the late 1800s. As the concepts of prosthetic
occlusion developed and were refined, it was natural
to extend this to the natural dentition. Edward H.
Angle (Figure 1-2), whose influence began to be felt about
1890, can be credited with much of the development of a
concept of occlusion in the natural dentition. Angle's
original interest was in Prosthodontics, and be taught in
that department in the dental schools at Pennsylvania and
Minnesota in the 1880s. His increasing interest in dental
occlusion and in the treatment necessary to obtain normal
occlusion led directly to his development of orthodontics
as a specialty, with himself as the "father of modern
orthodontics. "
The publication of Angle's classification of malocclusion
in the 1890s was an important step in the development
of orthodontics because it not only subdivided major
types of malocclusion but also included the first clear and
simple definition of normal occlusion in the natural dentition.
Angle's postulate was that the upper first molars were
the key to occlusion and that the upper and lower molars
should be related so that the mesiobuccal cusp of the upper
molar occludes in the buccal groove of the lower molar.
If this molar relationship existed and the teeth were
arranged on a smoothly curving line of occlusion (Figure
1-3), then normal occlusion would result. T h i s statement,
which 100 years of experience has proved to be correct—
except when there are aberrations in the size of teeth, brilliantly
simplified normal occlusion.