Root SurfaceThe root of the tooth is single, and
in a great many instances, the apical region is found to
be quite curved.
MAXILLARY FIRST MOLAR
The maxillary first molar (tooth #3 or #14),
illustrated in figures 4-40 and 4-41, is the sixth tooth
from the midline. The first molars are also known as
6-year molars, because they erupt when a child is about
6 years old
Facial SurfaceThe facial surface has a facial
groove that continues over from the occlusal surface,
and runs down to the middle third of the facial surface.
Lingual SurfaceIn a great many instances,
there is a cusp on the lingual surface of the
mesiolingual cusp. This is a fifth cusp called the cusp
of Carabelli, which is in addition to the four cusps on
the occlusal surface.
Figure 4-38.Surfaces of mandibular first bicuspid.
Occlusal SurfaceIn all molars the patterns of
the occlusal surface (fig. 4-41) are quite different from
those of the bicuspids.
The cusps are large and
prominent, and the broad grinding surfaces are broken
up into rugged appearing ridges and well-defined
grooves. An oblique ridge, which is not present on the
bicuspids, appears here (it also appears on maxillary
second and third molars).
RootsThe maxillary first molar has three roots,
which are named according to their locations-
mesiofacial, distofacial, and lingual (or palatal root).
The lingual root is the largest.
Figure 4-39.Surfaces of mandibular second bicuspid.
Facial SurfaceThe facial surface has the same
facial surface as the first bicuspid.
Lingual SurfaceThe lingual surface is similar
to that of the mandibular first bicuspid, with the
exception that there may be two lingual cusps present.
Occlusal SurfaceThe occlusal surface usually
has a total of three well-defined cusps. Viewed from
above, the three cusp present a Y-form pattern.
Figure 4-40.Surfaces of maxillary first molar.