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UPPER DENTAL AND MAXILLARY RETRUSIONS. 817
If the teeth are crowded, overlapping, or turned on their axes, a
correction of alignment may require the extraction of a bicuspid on
each side in order to regulate them without an abnormal protrusion of
their crowns. This is especially indicated when much retrusion of the
canine roots is desired.
IV. Upper Dental, and Maxillary Retrusions.
Facial imperfections which are due to insufficient fulness of contour
in the central features of the physiognomy are quite common, and vary
in degree from conditions that are hardly noticeable to those which may
well be classed among the most unhappy of facial deformities.
There are two distinct classes of this type of facial irregularity
one being due to a lack of development of the intermaxillary portion
of an otherwise harmonious upper jaw ; the other to the fact that the
entire upper jaw itself is too small and too posteriorly placed, in its
relations to other parts.
The teeth and alveolar process of the retracted parts are prevented
from assuming harmonious relations, and consequently the overlying
features are more or less depressed in proportion to the contruded or
retruded frame upon which they depend for their contour.
The primary cause of these conditions may be often very obscure
and admit of nothing more tangible than conjecture, and, not unlike
many of the causes of irregular teeth, be really immaterial to the work
of correction.
It may have been caused by the exertion of local physical forces
during the early years of immaturity (as, for instance, the mal-eruption
and occlusion of the teeth) ; or a local disturbance and interruption of
nutrition from prenatal or postnatal causes ; and lastly, but by no means
rarely, by inherent physical tendency.
Class 1 : Retruded Uppe)- Incisors and Iniermaxillary Process.—
In the more pronounced deformities of this class the physiognomy
will often appear flattened, with prominent cheek bones and protruding
chin and lower lip ; the upper incisors occlude evenly with or posterior
to the lower incisors, and at times are extensively inlocked in this posi-
tion, as instanced by the case fully described and illustrated in section I.
The upper incisors, which alone have their origin in the intermax-
illary process, are in their entirety posterior to a normal relative posi-
tion. The labial inclination of the crowns, together with the deepened
incisive fossae, will show at once the contruded position of the roots and
their maxillary surroundings.
The upper lip resting upon the retruded teeth and the overlying
process is proportionately depressed. Nor does the facial defect end
here. The entire lower portion of the nose, supported as it is by the
52
UPPER DENTAL AND MAXILLARY RETRUSIONS. 817
If the teeth are crowded, overlapping, or turned on their axes, a
correction of alignment may require the extraction of a bicuspid on
each side in order to regulate them without an abnormal protrusion of
their crowns. This is especially indicated when much retrusion of the
canine roots is desired.
IV. Upper Dental, and Maxillary Retrusions.
Facial imperfections which are due to insufficient fulness of contour
in the central features of the physiognomy are quite common, and vary
in degree from conditions that are hardly noticeable to those which may
well be classed among the most unhappy of facial deformities.
There are two distinct classes of this type of facial irregularity
one being due to a lack of development of the intermaxillary portion
of an otherwise harmonious upper jaw ; the other to the fact that the
entire upper jaw itself is too small and too posteriorly placed, in its
relations to other parts.
The teeth and alveolar process of the retracted parts are prevented
from assuming harmonious relations, and consequently the overlying
features are more or less depressed in proportion to the contruded or
retruded frame upon which they depend for their contour.
The primary cause of these conditions may be often very obscure
and admit of nothing more tangible than conjecture, and, not unlike
many of the causes of irregular teeth, be really immaterial to the work
of correction.
It may have been caused by the exertion of local physical forces
during the early years of immaturity (as, for instance, the mal-eruption
and occlusion of the teeth) ; or a local disturbance and interruption of
nutrition from prenatal or postnatal causes ; and lastly, but by no means
rarely, by inherent physical tendency.
Class 1 : Retruded Uppe)- Incisors and Iniermaxillary Process.—
In the more pronounced deformities of this class the physiognomy
will often appear flattened, with prominent cheek bones and protruding
chin and lower lip ; the upper incisors occlude evenly with or posterior
to the lower incisors, and at times are extensively inlocked in this posi-
tion, as instanced by the case fully described and illustrated in section I.
The upper incisors, which alone have their origin in the intermax-
illary process, are in their entirety posterior to a normal relative posi-
tion. The labial inclination of the crowns, together with the deepened
incisive fossae, will show at once the contruded position of the roots and
their maxillary surroundings.
The upper lip resting upon the retruded teeth and the overlying
process is proportionately depressed. Nor does the facial defect end
here. The entire lower portion of the nose, supported as it is by the
52
