Deck 6: Occlusion

Question 1

Each of the following is true of centric occlusion EXCEPT one.Which one is the EXCEPTION?

A) It is determined by the way teeth fit together.
B) It is the jaw position that affords greatest interdigitation of teeth.
C) It is related to occlusion.
D) It is determined by both muscle and bone.

Answer 1

D
Centric occlusion is NOT determined by muscle or bone.Very different from centric relation,centric occlusion is the jaw position that affords the greatest interdigitation of teeth.Thus,it is determined by the way teeth fit together and is related to occlusion.

Question 2

Class II occlusion is called distoclusion because the distal surface of the mandibular canine is distal to the mesial surface of the maxillary canine.

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.

Answer 2

A
Class II occlusion is called distoclusion.This question addresses the canine relationship;however the dental classification,described by E.H.Angle,more frequently relies on the relationship between maxillary and mandibular first molars.Note that for both Class II and Class III occlusion,the discrepancy must be by at least the width of a premolar.

Question 3

A crossbite occurs between only one maxillary tooth and one mandibular tooth because when more teeth are involved the condition is called overbite.

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.

Answer 3

E
A crossbite can exist between any number of teeth.The most common cause of crossbite is failure of the maxillae bones to grow in proportion to the mandible.Note that overbite is the extension of the incisal edges of the maxillary anterior teeth below the incisal edges of the mandibular teeth.Overbite is classified in degrees as slight,moderate,or excessive.

Question 4

Classification of occlusion by the Angle system primarily relies on the relationship between maxillary and mandibular canines because the anatomical features of molars are more difficult to interpret.

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.

Question 5

Class III occlusion is also known as mesioclusion because the mesiobuccal cusp of the mandibular first molar is mesial to the buccal groove of the maxillary first molar.

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.

Question 6

In ideal occlusion the mandibular first molar is stolarized because neither its mesial nor distal contact areas are open.

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.

Question 7

Occlusion must be evaluated bilaterally.An individual might have a Class I on one side and a Class III on the other side.

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.

Question 8

Each of the following may be present in Class III occlusion EXCEPT one.Which one is the EXCEPTION?

A) Prognathic facial profile may be present.
B) The mandible may be retruded.
C) The mandible has a mesial relationship with the maxilla.
D) The incisal margins of the mandibular incisors may lie in front of the maxillary incisors.

Question 9

From a lateral view,most teeth show a slight inclination in which direction?

A) Mesial
B) Distal
C) Vertical
D) Lingual

Question 10

An open bite refers to

A) a diastema
B) open contact between the arches
C) an overjet
D) premature contact
E) a crossbite

Question 11

The transverse occlusal curve seen from a posterior view is called the curve of Spee.The curve of Wilson refers to the fairly even curve of the buccal cusp tips of posterior teeth when viewed laterally.

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.

Question 12

Each of the following is a possible manifestation of a Class III occlusion EXCEPT one.Which one is the EXCEPTION?

A) Mandibular teeth are positioned facial to maxillary teeth.
B) Incisal margins of mandibular incisors lie in front of the middle third of the lingual surface of the maxillary incisors.
C) The mandible is retruded.
D) The distal surface of the mandibular canine is mesial to the mesial surface of a maxillary canine by at least the width of a premolar.

Question 13

A premature contact can be associated with each of the following EXCEPT one.Which one is the EXCEPTION?

A) Tender protagonist muscles
B) Teeth that are sensitive to percussion
C) Abnormal stress on the TMJ
D) Tooth mobility
E) Fractured teeth

Question 14

A comparison of 800 Australian aboriginal skulls shows that Class III occlusions were more successfully passed on through genetics than other occlusal patterns.Such analysis revealed that the prognathic profile and mesially protruded Class III mandible provided superior strength in incising and grinding food.

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.

Question 15

Each structure acts as an internal force in determining tooth alignment EXCEPT one.Which one is the EXCEPTION?

A) Tongue
B) Lips
C) Palate
D) Cheeks

Question 16

Retruded teeth are lingually inclined.Retruded permanent central incisors are associated with Class III occlusion.

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.

Question 17

A deep bite could result from hyperactive masticatory muscles because such muscular activity could prevent full eruption of posterior teeth.

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.

Question 18

A position that allows the greatest interdigitation of teeth is referred to in each of the following EXCEPT one.Which one is the EXCEPTION?

A) Acquired centric occlusion
B) Centric relation
C) Habitual occlusion
D) Intercuspal position
E) Convenience occlusion

Question 19

In Class II Division II,one would expect to see

A) overjet
B) retruded maxillary laterals
C) retruded maxillary centrals
D) edge to edge bite

Question 20

When a maxillary canine contacts its opposing antagonist before any other teeth occlude,it is described as anterior coupling.When one tooth hits ever so slightly more than the others,premature contact is occurring.

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.

Question 21

In Class I occlusion the mesiobuccal cusp of the maxillary first molar occludes with the buccal groove of the mandibular first molar.

Question 22

An 11-year-old child presents with wide spaces between mandibular second premolars and permanent first molars.These spaces are typical of

A) mesial step
B) distal step
C) leeway space
D) flush terminal plane

Question 23

When the maxilla outgrows the mandible,a Class II occlusion often results.

Question 24

Centric relation refers to the position of the retruded mandible to the maxilla.

Question 25

The average overjet of primary teeth is 2.0 mm.

Question 26

Protrusion of the maxillary anterior teeth can be caused by tongue-thrusting because improper tongue placement during swallowing exerts powerful pressure against lingual surfaces of anterior teeth.

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.

Question 27

Class II occlusion is the most common classification of occlusion.

Question 28

Tongue-thrusting can cause an overbite.

Question 29

The curve of Spee deepens with age.

Question 30

Dr.P.R.Begg described a dental classification system based on the relationship of the permanent first molars.