Page 24 - My FlipBook
P. 24
;
8 OF THE ALVEOLAE PROCESSES.
in the Lower-Jaw they are perpendicular, (m) but project inwards
at the posterior part, and describe a smaller circle than the body
of the bone upon which they stand ; as we shall observe more
particularly hereafter, when we come to treat of the Jaws of
Old People.
The Alveolar Processes of both Jaws should rather be con-
sidered as belonging to the Teeth, than as parts of the Jaws
for they begin to be formed with the Teeth, keep pace with
them in their growth, and decay, and entirely disappear, when
the Teeth fall ; so that, if we had no Teeth, it is likely we
should not only have no sockets, but not even these processes,
in which the sockets are formed and the Jaws can perforin
;
their motions, and give origin to muscles, without either the
Teeth, or Alveolar Processes. In short, there is such a mutual
dependence of the Teeth, and Alveolar Processes on each other,
that the destruction of the one seems to be always attended
with that of the other, (n)
and the regularly convex horse-shoe shape of the lower-jaw, strongly
characterize the human as opposed to quadrumanous configuration. In
Man, the molar series, including the premolars, describes a well-marked
curve with the convexity outwards. In the Anthropoid Apes, the teeth
from the last molar to the canine are arranged almost in a straight line,
with a very slight inflection inwards. They are parallel on the two sides,
and are joined at right angles by the line of the incisive alveoli, which
unites them in front. (1)
(m) [The direction of the incisor alveoli varies in individuals and in
races. In the melanous varieties, it is usual to find the anterior portion
of the alveolar border projecting in both jaws, especially in the upper
;
in the leucus and xanthous varieties, the anterior contour of the
incisor alveoli is more usually perpendicular. But individuals occur
in every variety in whom a greater or less degree of the prognathic con-
figuration is discernible.]
(n) [This observation is strictly correct however rapidly the gum be-
:
comes absorbed, whether from indigestion, the use of mercury, the
accumulation of calcareous matter, or that affection which is vulgarly
termed scurvy in the gum, the alveolar process never becomes exposed
(unless it be a dead portion exfoliating), but absorption of the bone
always keeps pace with that of the gum.—T. Bell.
(1) Op. cit.
8 OF THE ALVEOLAE PROCESSES.
in the Lower-Jaw they are perpendicular, (m) but project inwards
at the posterior part, and describe a smaller circle than the body
of the bone upon which they stand ; as we shall observe more
particularly hereafter, when we come to treat of the Jaws of
Old People.
The Alveolar Processes of both Jaws should rather be con-
sidered as belonging to the Teeth, than as parts of the Jaws
for they begin to be formed with the Teeth, keep pace with
them in their growth, and decay, and entirely disappear, when
the Teeth fall ; so that, if we had no Teeth, it is likely we
should not only have no sockets, but not even these processes,
in which the sockets are formed and the Jaws can perforin
;
their motions, and give origin to muscles, without either the
Teeth, or Alveolar Processes. In short, there is such a mutual
dependence of the Teeth, and Alveolar Processes on each other,
that the destruction of the one seems to be always attended
with that of the other, (n)
and the regularly convex horse-shoe shape of the lower-jaw, strongly
characterize the human as opposed to quadrumanous configuration. In
Man, the molar series, including the premolars, describes a well-marked
curve with the convexity outwards. In the Anthropoid Apes, the teeth
from the last molar to the canine are arranged almost in a straight line,
with a very slight inflection inwards. They are parallel on the two sides,
and are joined at right angles by the line of the incisive alveoli, which
unites them in front. (1)
(m) [The direction of the incisor alveoli varies in individuals and in
races. In the melanous varieties, it is usual to find the anterior portion
of the alveolar border projecting in both jaws, especially in the upper
;
in the leucus and xanthous varieties, the anterior contour of the
incisor alveoli is more usually perpendicular. But individuals occur
in every variety in whom a greater or less degree of the prognathic con-
figuration is discernible.]
(n) [This observation is strictly correct however rapidly the gum be-
:
comes absorbed, whether from indigestion, the use of mercury, the
accumulation of calcareous matter, or that affection which is vulgarly
termed scurvy in the gum, the alveolar process never becomes exposed
(unless it be a dead portion exfoliating), but absorption of the bone
always keeps pace with that of the gum.—T. Bell.
(1) Op. cit.
