Page 11 - My FlipBook

J^OMENCLATURE. 7

are divided into two groups, those occurring in the bicuspids and
molars forming one group, and those occurring in the incisors
and cuspids forming a separate group ; the forms of the surfaces
of these two groups of teeth being so different as to require dif-
ferences in consideration and treatment. Each of these groups
are again subdivided into mesial cavities and distal cavities.
Mesial cavities are those that are in surfaces of the teeth
toward the median line as we follow the curve of the arch.
Distal cavities are those that are in the surfaces of the teeth
furthest from the median line, following the curve of the arch.
Cavities occurring in the lingual surfaces of the upper incisors
are considered as a separate group, incisor lingual cavities.
Cavities occurring in the labial surfaces of the incisors and cus-
pids are called labial cavities.
In addition to these terms, all cavities which occur in the
axial surfaces of the teeth are called axial^ surface cavities.
In each of these localities decay has peculiarities in its mode
of attack, or there are differences of approach and of instrumen-
tation in their preparation for filling that render differences in
their consideration necessary.
Cavities are also divided into two groups, pit and fissure
cavities forming one group, and smooth-surface cavities
forming a second group. This constitutes a most important
division of cavities of decay, calling for a radical distinction in
consideration and treatment. The pit and fissure cavities have
their beginning in minute faults in the enamel of the teeth known
as pits, formed where three .or more lobes of the teeth join,
making imperfect closure of the enamel plates, as upon occlusal
surfaces of the bicuspids and molars and the lingual surfaces of
the incisors, or at the endings of grooves, as upon the buccal
surfaces of the molars. Fissure cavities begin in points of
imperfect closure of the enamel plates along the lines of the
grooves. These latter may occur along the lines of the grooves
of any of the teeth, but are seen mostly in the occlusal surfaces
of the bicuspids and molars.
Among the groups of cavities all of the occlusal cavities in
the bicuspids and molars are, in their beginning, pit or fissure
cavities. A part of the buccal cavities in the molars are pit or
fissure cavities occurring in the buccal pits or fissured grooves,
and part are smooth-surface cavities, occurring in the smooth