Page 54 - My FlipBook

50 CARIES OF THE TEETH.

deposit does thus serve as a protection, the removal

of the discolored portion would subject the dentine to
a renewed attack of caries, which experience assures
us it does not do, hut that after some time it assumes
the dark hue again. Those who maintain this opinion,
refer, in support of it, to the fact that a deposit of
oxyd of silver being made upon a decay of light color,
)Sy the use of nitrate of silver, the progress of the
decay is thereby retarded. This retardal, however,
is effected more probably by a change in the character
of the decay, than by any protection afforded by the

coating of oxyd of silver.
Some sensitiveness commonly accompanies caries.
It does not often amount to pain, but is rather a sense
of uneasiness; yet from change of temperature or
contact of acids or hard substances, intense pain may
be produced. Dr. Koecker remarks that caries is
most tender in its first stages; and Dr. Cone, that
when a tooth is attacked by it, the sensitiveness is
increased. The surface of the dentine, or that part
united to the enamel, is susceptible of the most
acute sensitiveness, this being on the periphery of

the vital force. When there is inflammation of
the dentine, intense pain may be produced by the
contact of an instrument, in a cavity of decay, at the
line of union of the dentine with the enamel, and very
little sensitiveness be present elsewhere in the cavity.