Chapter 10 Orofacial Anatomy |Complete Latest Update with A+ Graded Answers 2026 Edition

Chapter 10 Orofacial Anatomy |Latest Update with A+
Graded Answers
Tooth roots do not always curve. If they do curve, they typically curve distally.
a. Both statements are true
b. The first statement is true; the second statement is false.
c. The first statement is false; the second statement is true.
d. Both statements are false.

a.
Teeth exhibit extreme amounts of anatomical variation; however a general rule of identification
is that roots do not always curve, which implies that root curvature certainly exists. The rule
further states that root curvature usually is in a distal direction. However, the rule further states
that it is not uncommon for roots to curve mesially.

Third molars are generally larger than first molars because a general rule of tooth identification
states that permanent molars are generally taller in height and have more cusps the more
posteriorly they are placed.
a. Both the statement and the reason are correct and related.
b. Both the statement and the reason are correct but are NOT related.
c. The statement is correct, but the reason is NOT correct.
d. The statement is NOT correct, but the reason is correct.
e. NEITHER the statement NOR the reason is correct.

e.
The general rule of tooth identification applicable to molars states that permanent molars are
typically smaller in height and have fewer cusps the more posteriorly they are positioned. For
example, the permanent first molar usually has five cusps and is larger than either a second or
third molar.

Secondary anatomy refers to anatomical features of second molars and premolars. Tertiary
anatomy refers to unique anatomical features of third molars.
a. Both statements are true.
b. The first statement is true; the second statement is false.
c. The first statement is false; the second statement is true.
d. Both statements are false.

c.
Secondary anatomy refers to extra grooves and pits in addition, or secondarily, to the main
primary developmental anatomy in any tooth. Tertiary anatomy refers specifically to the

, extremely shallow and more numerous grooves, pits, and lines present in third molars. Tertiary
features give third molars a more wrinkled appearance than first or second molars.

The crowns of the maxillary incisors are wider mesiodistally than labiolingually. The roots of
maxillary incisors are oval in cross section.
a. Both statements are true.
b. The first statement is true; the second statement is false.
c. The first statement is false; the second statement is true.
d. Both statements are false.

b.
The crowns of maxillary incisors are wider in mesiodistal dimension than in faciolingual
dimension. The second statement is false because the roots of maxillary incisors are triangular
in cross section. The roots of the mandibular incisors, however, are oval in cross section. These
facts apply to both central and lateral incisors.

Which incisor exhibits a slight distolingual rotation?
a. Maxillary central
b. Maxillary lateral
c. Mandibular central
d. Mandibular lateral

d.
The distal half of the incisal edge of the mandibular lateral incisor is rotated toward the lingual
side. This can also be described as a slight distolingual rotation. This rotation is most apparent
from the incisal view.

The lingual cusp of the maxillary first premolar is longer than the facial cusp. This tooth often
has two roots, one mesial and one distal.
a. Both statements are true.
b. The first statement is true; the second statement is false.
c. The first statement is false; the second statement is true.
d. Both statements are false.

d.
The lingual cusp of the maxillary first premolar is shorter than the facial cusp. While it is true
that this tooth often has two roots, they are the buccal and lingual roots. For comparison,
mandibular molars have a mesial and distal root.

Which premolar has a small lingual cusp and no central pit?
a. Maxillary first
b. Maxillary second