Page 584 - My FlipBook

582 EXTRACTION OF TEETH.
In tlic iij)])('r jaw the bone is tliin over the position of the molar teeth,
and their roots are eoinparatively sti'aijjjht none of these should be
;
diffieult to extraet. Tlie hueeal roots of the first molar are somewhat
diver only slightly as they leave the erown and close in at the points. The
Fig. 516.
Mtc

T ya Hp
Hs, Hiatus semilunaris; Mec, middle etlimoidal cells; CI, crystalline lenses; Up, uncinate pro-
cess 3It, middle turbinated bone ; Mm, middle meatus ; Ms, maxillary sinus Ini, inferior
; ;
meatus; It, inferior turbinated bone; Vm, vestibule of mouth; Isf M, first molar; Dis. r. IM M,
distal root first molar; Idn, inferior dental nerve; T, tongue; Ns, nasal septum; Hp, hard
palate.
roots of the third molar are too-ether and slig-htlv curved backward. In
the lower jaw the roots are comparatively straight. Those of the first
molar are s])read only a little apart, this being the usual condition.
The roots of the second molar are almost straight and are nearly parallel
with each other. The anterior root of the third molar curves slightly
backward until it joins the posterior root.
Fig. 515 is taken from the left side of the same jaw as Fig. 514. In
Fig. 514 the roots have been exposed down to their apices ; in Fig. 515
only the external or cortical plate has been removed. These two illus-