Midterm Questions from Drive

Question 1

what is “mesial step”?

Answer 1

the permanent MD first molar is mesial to the permanent MX first molar

Question 2

curve of spee

Answer 2

anterior-posterior ‘curve’ along the buccal cusp tips of the permanent MD posterior teeth

Question 3

condylar path is determined by what skeletal component of mastication system?

Answer 3

articular eminence of the temporal bone

Question 4

Class 3 dental occlusion?

Answer 4

MB cusp of the permanent MX first molar is DISTAL to the MB cusp of the permanent MD first molar

Question 5

leeway space

Answer 5

spaces MESIAL to the developing permanent first molars

Question 6

primate space

Answer 6

spaces mesial to the primary MX canine and DISTAL to the primary MD canine

Question 7

centric relation

Answer 7

is a skeletal position and does not refer to a tooth contact position
*most upward, unrestrained position of mandible in glenoid fossa

Question 8

What makes up the stationary component of the mastication system?

Answer 8

MX teeth

Question 9

boundary lubrication refers to?

Answer 9

the movement of synovial fluid from one capsular area in the TMJ apparatus to another during joint movement

Question 10

What muscle along with the masseter muscle forms a ‘sling’ at the MD angle?

Answer 10

medial pterygoid muscle

Question 11

curve of wilson

Answer 11

transverse occlusal ‘curve’ in a buccal-lingual direction of the permanent posterior cusp tips is termed

Question 12

as articular pressure increases the condyles seats on the?

Answer 12

thin, intermediate zone of the disc

Question 13

which statement is true concerning the relationship of muscles and the articular surface of the glenoid fossa?

Answer 13

as articular pressure increases the condyles seats on the thin, intermediate zone of the disc

Question 14

when the mandible and condyle/disc assembly are in a rest position, the condyle and disc are positioned?

Answer 14

anteriorly

Question 15

when the mandible and condyle/disc assembly are in a rest position, the condyle and disc are positioned anteriorly what best describes the forces exerted by the superior lateral pterygoid muscle and posterior retrodiscal lamina?

Answer 15

the anterior and medial force exerted by the superior lateral pterygoid muscle exceeds the posterior elastic retrodiscal lamina force

Question 16

motor unit consists of

Answer 16

one motor neuron and a varying number of muscle fibers

Question 17

describe the motor unit in the lateral pterygoid muscle

Answer 17

lateral pterygoid muscle has a few muscle fibers per motor neuron and controls PROTRUSIVE change in mendibular position

Question 18

Myotactic reflex?

Answer 18

stretch

*this reflex causes muscle contraction when a sudden force stretches the muscle

Question 19

What is responsible for rotational movement in the TMJ?

Answer 19

inferior condyle/disc complex

Question 20

T/F… ligaments of the TMJ stretch and produce functional movement

Answer 20

false (they do no stretch)

Question 21

T/F… the articular disc is made of fibrocartilaginous tissue and functions as a true articular surface

Answer 21

true

Question 22

what is responsible for the translational movement of TMJ?

Answer 22

superior condyle/disc complex

Question 23

What type of sensory receptors convey afferent neuron information related to pain and discomfort

Answer 23

nocioceptors

Question 24

example of heterotropic pain? definition?

Answer 24

‘referred pain’

**where the SITE and SOURCE of the pain are different

Question 25

major function of the masticatory system include?

Answer 25

mastication of speech

Question 26

what two phases is the the "chewing stroke" in humans?

Answer 26

1) opening phase | 2) closing phase

Question 27

describe the chewing stroke assuming an Angle's Class 1 occlusion

Answer 27

the mandible drops downward and laterally in the opening phase and the closing phase involves crushing and grinding movements

Question 28

range of force of mastication?

Answer 28

35-65kg in humans

Question 29

where is the greatest chewing force in dentition?

Answer 29

1M and 2PM

Question 30

what happens to occlusion if contact between teeth is lost?

Answer 30

opposing teeth tend to supererupt causing proximal drifting adjacent teeth

Question 31

posterior teeth have inner and outer aspects of the total buccolingual width. describe the outer aspect?

Answer 31

the outer aspect is the area between the cusp tip and the external height of contour

Question 32

what % of patients have a preferred chewing side?

Answer 32

78%

Question 33

T/F... incisal edges of the incisor teeth closely approximate when "S" sounds are made?

Answer 33

true

Question 34

T/F... proximal forces on teeth can cause 'mesial drifting' over time?

Answer 34

true

Question 35

T/F... the occlusal table is approximately 50% of the total buccolingual width of a posterior tooth?

Answer 35

true

Question 36

T/F... in posterior cross-bite situation, the maxillary lingual cusps contact in the central fossa area of the mandibular teeth

Answer 36

false

Question 37

T/F... centric cusps or supporting cusps are the mandibular buccal cusps and the maxillary lingual cusps

Answer 37

true

Question 38

where does the ML cusp of th MX 1M occlude in class 1 occlusal relationship?

Answer 38

CF of MD 1M

Question 39

where does the MB cusp of the MX 1M occlude in class 3?

Answer 39

embrasure space between the MD 1M and 2M

Question 40

which acronym applies to posterior tooth contacts in protrusive MD movement?

Answer 40

DUML

Question 41

describe a tooth contact in a left working side laterotrusice MD movement?

Answer 41

the inner inclines of the MX BCs oppose the outer inclines on the MD BCs

Question 42

what occurs when the mandible has opened a distance of 20-25mm during a posterior border movement?

Answer 42

a translational opening continues to a distance of 40-60mm

Question 43

T/F... MD anterior teeth usually contact the MX anterior teeth on the lingual surface 4mm gingival to the incisal edge?

Answer 43

true

Question 44

MD tooth BCs may move ___mm _____ in a retrusive mandibular movement?

Answer 44

1-2mm posteriorly

Question 45

rotetional MD movement refers to?

Answer 45

translational movement of an object in the same direction

Question 46

what is the most superior position of the MD condyles from which hinge axis movement can occur is called?

Answer 46

centric relation position

Question 47

the absence of a slide from CR to the MI position occurs in only ___% of the pospulation

Answer 47

10%

Question 48

T/F... sagittal plane border movements of the mandible are defined by a "shield-shaped" pattern?

Answer 48

false | *vertical border movement

Question 49

maximum intercuspation

Answer 49

is a skeletal position which involves a tooth contact position *HOW teeth come together in full occlusion

Question 50

what is the movable component of the masticatory system? stationary?

Answer 50

mandibular teeth | **(maxillary make up stationary)

Question 51

T/F... as articular pressure increases the condyles seats on the thin, intermediate zone of the disc

Answer 51

true

Question 52

weeping lubrication

Answer 52

synovial fluid in one tissue goes into another

Question 53

inferior vs superior condyle disc movement?

Answer 53

* inferior= rotates about axis | * superior= translational movement