Page 701 - My FlipBook

;

ETIOLOGY OF DENTAL IRREGULARITIES. 699
Fig. 617.

Symphysis of superior maxillae, before spreading arch.
quickly than in any other way and maintaining crowns and roots in an
upright position.
Fig. 618.

Separation of superior maxillse at symphysis, after spreading arch.

4. Depression of the Roots in the Sockets.—In reducing
cases of lack of anterior occlusion by means of elastics extending from
a chinpiece to a cap to the top of the head, Prof. Guilford ^ savs :
"The condyles of, the lower jaw will be tipped somewliat out of their
cavities, and the latter be partially filled up with new ossific material
at the same time the tendency will be to shorten the posterior occlud-
ing teeth by forcing them farther into their sockets."
Charles S. Tomes ^ in a similar case questioned whether "the closure
of the front teeth was effected by an elongation of the ascending
ramus of the jaw or by the antagonizing teeth being depressed and, so
to speak, forced farther into their sockets," and concludes, " I am
inclined to think the latter is the true explanation."
1 Orthodontia, 2d ed., p. 196. ^ Kingsley's Oral Defoi-mities, p. 121.