Exam 1 (Review slides 1-10) Flashcards
Outer Oblique portion of temporomandibular ligament has what function?
Limits normal rotational opening movement
Inner horizontal portion of temporomandibular ligament has what function?
Limits posterior movement of condyle & disc
5 main points about Centric Relation:
- It is a condylar position, and does not need any tooth contact to be obtained
- Establishes the position of the condyle in a superior and anterior location with the disc properly interposed between the condyle and the temporal bone
- Articulation on the thin portion of the articular disc
- Described as the most stable position of the condyle
- A position of the mandible where the musculature displays minimal tonus
6 main points about Maximum Intercuspation clinical conditions
- Teeth determine the occlusal position
- If centric relation and maximum intercuspation do not coincide, the patient will have a “slide”
- Most patients have some degree of a slide from centric relation into maximum intercuspation (1-2 mm)
- Maximum intercuspation is simultaneous contact of all the teeth and is the “endpoint” of the slide
- All occlusal forces should be concentrated down the long axis of posterior teeth
- The maximum intercuspation position is dynamic in nature and will change throughout a patient’s life.
T or F, Centric relation is described as the least stable position of the condyle
False, most stable
T or F, The maximum intercuspation position is dynamic in nature and will change throughout a patient’s life
True
T or F, Centric relation establishes the position of the condyle in a inferior and anterior location with the disc properly interposed between the condyle and the temporal bone
False, Superior and Anterior
T or F, Maximum intercuspation is asynchronous contact of all the teeth and is the “starting point” of the slide
false, It is simultaneous contact and is the “endpoint” of the slide
T or F, Centric Relation is a condylar position, and does not need any tooth contact to be obtained
True
T or F, Centric relation is a position of the mandible where musculature displays maximal tonus
False, Minimal tonus
Name the 3 normal functional activities of the Temporalis
- Elevates the mandible in a superior direction to eventually contact the maxillary teeth
- Retracts or retrudes the mandible
- Positions the mandible to obtain centric relation
What is the parafunctional activity of the Temporalis
Causes clenching of the teeth to occur when the muscle is overused.
T or F, the Temporalis is normally involved with producing lateral movement of the mandible
False, is NOT normally involved
The relationship of the medial pole of the condyle and the medial pterygoid muscle on one side establishes what?
The mid-most position of the mandible at centric relation
What makes the normal curve of occlusion possible?
The interaction of the medial pole of the condyle with the steep medial wall of the fossa prevents the mandibular posterior teeth from moving straight horizontally toward the midline
Can the superior head of the lateral pterygoid be palpated?
This muscle is deep in placement and is mostly covered by the medial pterygoid, but the clinician can palpate some portion of the muscle.
The superior head of the lateral pterygoid works in concert with what?
the action and inactivity of the inferior head of the lateral pterygoid.
Name the parafunctional activity of the superior head of the lateral pterygoid?
It frequently displays a spasm as a result of some types of occlusal dysfunction
- This will result in the articular disc being pulled anteriorly out of the glenoid fossa
What are the two normal functional activities of Superior head of the lateral pterygoid muscle
- It maintains a sustainable and consistent position of the articular disc
- It is progressively active during closing movement of the mandible
What establishes the mid-most position of the mandible at centric relation
The relationship of the medial pole of the condyle and the medial pterygoid muscle on one side
Actions of the mylohyoid muscle (3)
- Slightly depress the mandible
- Elevate the hyoid, the floor of the oral cavity, and the tongue
- Very important during speaking and swallowing
The 4 actions that occur during the late phase of the mandibular opening movement
- Inferior head of the lateral pterygoid is at maximum point of contracture
- The condyle has moved as far to the anterior as it can possible move
- The articular disc has rotated posteriorly over the posterior portion of the head of the condyle
- The superior retrodiscal tissues are in maximum tautness and cannot further hold the articular disc in position over the head of the condyle without either stretching or tearing.
What prevents any further anterior movement of the condyle as the inferior head of the lateral pterygoid is at maximum point of contracture
The temporomandibular ligament
Stylomandibular ligament
Sphenomandibular ligament
Capsular ligament
Where is the condyle located when is has moved as far to the anterior as it can possibly move
It is now located at the inferior border of the slope of the articular eminence
