Station Exam- Part II

Question 1

What are the uses of the articulator?

Answer 1

1. diagnosis
2. treatment planning
3. communicate with patients/patient education
4. fabrication prosthesis/restorations

Question 2

What are characteristics of semi-adjustable articulators?

Answer 2

1. used the most
2. allow opening and closing movements
3. allow excursive (lateral) and protrusive movements

Question 3

What are characteristics of non-adjustable or “hinge” articulators?

Answer 3

1. allow only opening and closing movements
2. can be used for single posterior restorations
3. their use can create a change in the closure angle- and by doing so the final restoration will present premature contacts

Question 4

Describe and Arcon semi-adjustable articulator:

Answer 4

• condyles in lower member
• condylar inclination in the upper member

Question 5

When the condylar indication is in the _____ member , this closely resembles the patients mouth

Answer 5

upper member

Question 6

Describe a Non-Arcon semi-adjustable articulator:

Answer 6

• mainly used for removable prosthodontics
• condyles in upper member
• condylar indication in the lower member

Question 7

What type of articulator is ours?

Answer 7

Arcon (semi-adjustable)

• condyles in lower member and condylar inclination in upper member

Question 8

What is the purpose of a facebow?

Answer 8

to orient the maxillary cast to the rotational axis in three planes

Question 9

Using a facebow will result in ___ articulation of subsequent ___ casts

Answer 9

reproducible; maxillary

Question 10

The facebow orients the dental cast in the same relationship to the ____ as the articulator

Answer 10

opening axis

Question 11

What are usually the anatomic references?

Answer 11

1. mandibular condyles
2. transverse horizontal axis
3. one other selected anterior point

Question 12

What does an ear-bow index to and what does it register?

Answer 12

The external auditory meatus; registers the relation of the maxillary arch to a horizontal reference plane

Question 13

What is the third point of reference?

Answer 13

The anterior reference point, it should be repeatable and reproducible. It is parallel to the upper and lower arms of the articulator

Question 14

The facebow orients a maxillary cast to the:

Answer 14

reference plane

Question 15

The reference plane requires 3 points including:

Answer 15

2 on each side of face, and one on the anterior face

Question 16

When should you use a facebow?

Answer 16

• when cusp teeth are present,
  -I nterocclusal records are made at an increased occlusal vertical dimension
• the OVD is subject to change
• alterations in occlusal surfaces are necessary

Question 17

Where does the mandible articulate with the skull?

Answer 17

at the temporal bone

Question 18

How many bones make up the maxilla and where do they fuse?

Answer 18

two; fuse at mid-palatal suture

Question 19

What is the superior border of the maxilla?

Answer 19

floor of nasal cavity and orbit

Question 20

What is the inferior border of the maxilla?

Answer 20

palate and alveolar ridge

Question 21

What are the components of the maxilla ?

Answer 21

body and processes (zygomatic, frontal, alveolar, and palatine)

Question 22

True or false; the maxilla is the largest and strongest bone in the skull

Answer 22

true

Question 23

What are the components of the mandible?

Answer 23

body (horizontal part) & ramus (vertical part)

Question 24

What is the superior aspect of the mandible?

Answer 24

alveolar crest and teeth

Question 25

What is the posterior aspect/body of the mandible?

Answer 25

mandibular angle and ascending ramus

Question 26

What makes up the ascending ramus?

Answer 26

coronoid process and condyles (where protrusions and lateral movements of the mandible occur)

Question 27

What do the condyles articulate with?

Answer 27

cranium

Question 28

What is the mediolateral length of the condyles?

Answer 28

15-20mm

Question 29

What is the anterior-posterior width of the condyles?

Answer 29

8-10mm

Question 30

What does the squamous portion of the temporal bone articulate with?

Answer 30

mandibular condyle

Question 31

What is the articular eminence function?

Answer 31

Thick dense bone to tolerate heavy forces

Question 32

What are the muscles of mastication?

Answer 32

masseter, temporalis, medial pterygoid, lateral pterygoid

Question 33

what are the 2 heads of the masseter and how do their fibers run?

Answer 33

A- superficial head: fibers run downward and backward B- Deep head: fibers run in vertical direction

Question 34

What are the 3 distinct divisions of the temporalis and how do their fibers run?

Answer 34

A- anterior: fibers run vertically- only does elevation B- middle: fibers run obliquely across the lateral aspect of the skull- does elevation and recursion C- posterior: fibers run horizontally and come forward above the ear to join other temporalis fibers- only does retrusion

Question 35

What are the two heads of the lateral (external) pterygoid?

Answer 35

Superior lateral pterygoid- smaller Inferior lateral pterygoid- extends backwards, upwards, and outward almost two separate muscles!

Question 36

What is the function of the masseter?

Answer 36

- elevates the mandible - provides force for chewing - Superficial head: aids in protrusion - Deep head: stabilizes the condyle against the eminance

Question 37

The superficial head of the masseter aids in:

Answer 37

protrusion

Question 38

The deep head of the masseter:

Answer 38

stabilizes the condyle against the eminance

Question 39

What is the functions of the Anterior temporalis?

Answer 39

raises mandible vertically

Question 40

What is the function of the middle temporalis?

Answer 40

elevates & retrudes the mandible

Question 41

What is the function of the posterior temporalis?

Answer 41

aids in recursion of the mandible

Question 42

What is the function of the medial (internal) pterygoid?

Answer 42

- elevates the mandible - protrudes the mandible

Question 43

What does unilateral contraction of the the medial pterygoid result in?

Answer 43

mediotrusion (mandible moves toward the midline)

Question 44

What does bilateral contraction of the lateral pterygoid inferior head result in?

Answer 44

causes condyles to be pulled down the articular eminences and the mandible is protruded

Question 45

What does unilateral contraction of the lateral pterygoid inferior head result in?

Answer 45

causes mediotrusive movement (downward, forward, & medially)

Question 46

When is lateral pterygoid superior lateral head in active?

Answer 46

inactive during mandibular opening

Question 47

When is the lateral pterygoid superior lateral head active?

Answer 47

with elevator muscles (closure of the mandible)

Question 48

What muscle is involved in the power stroke?

Answer 48

lateral pterygoid superior head- active during mandibular closure against resistance

Question 49

What two muscles of mastication form the masseter sling, and what is its function?

Answer 49

masseter and medial pterygoid, function to keep mandible in place and stabilize it

Question 50

What is the function of the suprahyoids?

Answer 50

elevate the hyoid bone and depress the mandible when the hyoid bone is fixed

Question 51

Depression of the mandible involves contraction of what muscles? Depression of the mandible involves relaxation of what muscles?

Answer 51

inferior lateral pterygoid and digastric masseter, medial pterygoid and temporalis

Question 53

Elevation of the mandible involves contraction of what muscles: involves relaxation of what muscles:

Answer 53

contraction: masseter, medial pterygoid, temporalis, and superior lateral pterygoid relaxation: Inferior lateral pterygoid and digastric

Question 54

Right lateral movement of the mandible involves: contraction of: relaxation of:

Answer 54

contraction: left inferior lateral pterygoid relaxation: right inferior lateral pterygoid and slight relaxation of elevators

Question 55

Left lateral movement of the mandible involves: contraction of: relaxation of:

Answer 55

contraction: right inferior lateral pterygoid relaxation: left inferior lateral pterygoid and slight relaxation of pterygoids

Question 56

Protrusion of the mandible (moves mandible forward in straight line): contraction of: relaxation of:

Answer 56

contraction: mainly inferior lateral pterygoids assisted by masseter and medial pterygoids Relaxation: N/A

Question 57

Retrusion of the mandible (mandible does back) involves: contraction of: relaxation of:

Answer 57

contraction: temporalis relaxation: N/A