Page 192 - My FlipBook
P. 192
:
188 CLASSIFICATION OF DECAYED CAVITIES.
between the walls and the filling, and the purpose for
which this was inserted would be entirely defeated.
Many operators ream the orifices of all the small
and medium-sized cavities of this class, in order
thereby to make a better finish to the border of the
rilling. Some operators prefer in all cases to remove
the angle formed by the wall of the cavity and the
surface of the tooth about the orifice, giving a rounded
form to the border of the orifice, the object being to
avoid fracturing or comminuting the edge of the
enamel or dentine about the cavity. All acute angles
in these cavities, especially if they extend to the
orifice, should be obliterated, since it is impossible to fill
them perfectly. This obliteration can be effected with
a miniature chisel, or with the appropriate excavator.
After the formation of the cavity, the next particu-
lar is so to arrange as entirely to exclude moisture,
whether from the saliva or from the breath. Ordi-
narily, in operations on the superior teeth, the follow-
ing arrangement will be sufficient for the purpose
Wipe dry the mucous membrane about the mouth of
the duct of Steno ; lay directly upon this a piece of
heavy blotting paper, or a roll of bibulous paper; then
take a napkin folded cornerwise, place the end of it
upon the paper, between the cheek and the gum,
passing it back of the tooth to be operated upon,
along the palatal surfaces of the teeth and the gums
188 CLASSIFICATION OF DECAYED CAVITIES.
between the walls and the filling, and the purpose for
which this was inserted would be entirely defeated.
Many operators ream the orifices of all the small
and medium-sized cavities of this class, in order
thereby to make a better finish to the border of the
rilling. Some operators prefer in all cases to remove
the angle formed by the wall of the cavity and the
surface of the tooth about the orifice, giving a rounded
form to the border of the orifice, the object being to
avoid fracturing or comminuting the edge of the
enamel or dentine about the cavity. All acute angles
in these cavities, especially if they extend to the
orifice, should be obliterated, since it is impossible to fill
them perfectly. This obliteration can be effected with
a miniature chisel, or with the appropriate excavator.
After the formation of the cavity, the next particu-
lar is so to arrange as entirely to exclude moisture,
whether from the saliva or from the breath. Ordi-
narily, in operations on the superior teeth, the follow-
ing arrangement will be sufficient for the purpose
Wipe dry the mucous membrane about the mouth of
the duct of Steno ; lay directly upon this a piece of
heavy blotting paper, or a roll of bibulous paper; then
take a napkin folded cornerwise, place the end of it
upon the paper, between the cheek and the gum,
passing it back of the tooth to be operated upon,
along the palatal surfaces of the teeth and the gums
