Exam I Review Flashcards
What does the Outer Oblique Portion (OOP) limit?
Limits normal rotational opening movements
What does the Inner Horizontal Portion(IHP) limit?
Limits posterior movement of condyle & disc
Centric Relation is:
a) Condylar postion…
b) Establishes the position of the what?
c) Articulation is on the what?
d) It is described as …
e) A position of the mandible where…
a) CONDYLAR position, & DOES NOT need any tooth contact to be obtained.
b) Establishes position of condyle in a SUPERIOR and ANTERIOR location w/ disc properly interposed between condyle & TEMPORAL bone.
c) Articulation on the THIN portion of the articular disc
d) Described as MOST STABLE position of the condyle
e) A position of mandible where the MUSCULATURE display MINIMAL TONUS
Maximum Intercuspation Clinical Conditions:
- ________ determines the occlusal position
- If central relation & maximum intercuspation do not coincide the patients will have a ___________
- Most patients have some degree of a slide from centric relation into ___________________ (it is approximately ___________ in length)
- Maximum Intercuspation is simultaneous contact of all teeth & is the ________ of the slide
- All occlusal forces should be concentrated ____________________________
- _____________ position is DYNAMIC in nature and will CHANGE throughout a patient’s life
- Teeth
- “Slide”
- Maximum intercuspation
- 1-2 mm
- “endpoint”
- Down the long axis of posterior teeth
- Maximum intercuspation
What is considered as the NORMAL functions/actions of the TEMPORALIS?
1) ELEVATE (closing) mandible in a superior direction to eventually contact maxillary teeth
2) RETRACTS or RETRUDES mandible
(Helps seat the condyles into mandibular fossa)
3) Positions mandible to obtain centric relation (CR)
* It is not normally involved w/ producing LATERAL movement of the mandible.
What is considered as parafunctional functions/actions of the TEMPORALIS?
1) Clenching of the teeth to occur when the muscle is overused
Regarding the Medial Pole of Condyle & Medial Pterygoid Muscle (3)
1) Relationship of the medial pole of condyle & medial pterygoid on one side establishes the MID-MOST POSITION of the MANDIBLE at CENTRIC RELATION.
2) Normal curve of occlusion is possible because the interaction of the medial pole of the condyle w/ the steep medial wall of the fossa PREVENTS mandibular POSTERIOR teeth from moving straight HORIZONTALLY toward the MIDLINE
3) As a result ideal patents, mandibular lateral translation (or direct lateral movement of mandible toward midline) is impossible from fully seated positions of condyle in fossa.
(Not mentioned in review)
What are the actions of the Superior Head of the LATERAL PTERYGOID MUSCLE?
1) Maintains a sustainable & consistent psotion of the articular disc (normal function)
2) It is PROGRESSIVELY active during “CLOSING” movement of mandible (normal function)
3) It FREQUENTLY displays SPASM as a result of some types of OCCLUSAL DYSFUNCTION
-spasm will result in articular disc being pulled anteriorly out of glenoid fossa
(Parafunctional activity)
4) Muscle works in concert w/ ACTION & INACTIVITY of the inferior head of the lateral pterygoid
5) Muscle of mastication is DEEP in PLACEMENT & is mostly covered by the medial pterygoid, clinician CAN palpate SOME portion of muscle
What are the actions of the MYLOHYOID MUSCLE?
1) Will SLIGHTLY DEPRESS the mandible
(open, doesn’t close)
2) ELEVATE the HYOID, the FLOOR of the ORAL CAVITY and the TONGUE
3) Very important during SPEAKING & SWALLOWING
Which actions occur during LATE MANDIBULAR OPENING MOVEMENT?
1) INFERIOR HEAD of the Lateral Pterygoid is at MAXIMUM POINT of contracture
- TM ligament, stylomandibular ligament, sphenomandibular ligament & capsular ligament “prevents” any further anterior movement of condyle.
2) CONDYLE has moved as FAR to the ANTERIOR as it CAN MOVE
- Now located @ inferior border of slope of articular eminence
3) Articular disc has ROTATED POSTERIORLY OVER the POSTERIOR PORTION of the HEAD of the CONDYLE
- Superior head of lateral pterygoid is maximum contracture, attempting to hold articular disc over the head of condyle.
4) SUPERIOR RETRODISCAL TISSUE are in MAXIMUM TAUTNESS (not inferior) & CAN’T further hold articular disc in position over the head of the condyle w/out either stretching or tearing.
- Posterior portion of collateral ligament is LACKING in tautness
- Anterior portion is TAUT
What is the directional length of the Anterior, Middle, & Posterior TEMPORALIS force vector?
-SUPERIOR
What is the directional length of the MASSETER force vector?
-SUPERIOR
What is the directional length of the MEDIAL PTERYGOID MUSCLE** force vector?
**SUPERIOR & SLIGHTLY MEDIAL (MEDIOTRUSIVE) ***
What is the directional length of the INFERIOR HEAD of the LATERAL PTERYGOID muscle force vector:
-ANTERIOR & MEDIAL (slightly mediotrusive)
Like all articulated joints in the human body the temporomandibular joint is innervated by what?
- The SAME nerve that provides motor & sensory innervation to muscles that control it.
- Primarily the TRIGEMINAL NERVE (V)
MOST of the innervation to the TMJ is by the what?
- The AURICULOTEMPORAL NERVE (75%)
- Additional innervation (SENSORY) is supplied by the DEEP TEMPORAL & MESSETERIC NERVE branching of TRIGEMINAL-3 (V3)
Primary vascularization of the TMJ is with the ?
SUPERFICIAL TEMORAL BRANCH of the external carotid ARTERY
The condyle receives vascular supply throughout what?
Its MARROW SPACES from INFERIOR ALVEOLAR ARTERY & FEEDER VESSELS from other branches that perforate head from various angles
Why does the maxillary arch form DOMINATE the mandibular arch?
1) Maxillary arch is LARGER** than mandible from the distal of a 3rd molar on one side thru middle of each tooth to the 3rd molar on the other side
2) Maxillary arch is **WIDER* or larger in measurements from R/L sides
3) Esthetics are embedded MORE in the maxillary arch than in mandibular b/c smile line is extremely evident w/ maxillary ant. teeth
Intra-arch Alignment of Teeth:
- Teeth primarily contact their ___________?
- Most teeth contact ___________________?
- Which 2 teeth only have ONE antagonist in the opposing arch?
- Namesake in the opposing arch
- One additional tooth in the opposing arch
- The maxillary third molars and mandibular central incisors
Regarding Plane of Occlusion:
- The ideal plane is?
- A flat plane allows what?
- The proper plane of occlusion will permit what?
- A curved plane permits what?
- How are teeth positioned in the arch?
- The IDEAL plane is NOT FLAT
- A FLAT plane allows for TOO MANY contacts on most POSTERIOR TEETH on BOTH sides of the mouth
- The PROPER PLANE of occlusion will PERMIT SIMULTANEOUS FUNCTIONAL contacts to occur in controlled areas of arch
- A CURVED plane permits MAXIMUM USE of TOOTH CONTACTS during FUNCTION
- The teeth are “strategically positioned” in the ARCHES at VARIED & COORDINATED degrees of inclination
What is forces exerted on the first premolars are approximately what ?
50% LESS than those exerted on the 3rd molars
Occlusal contacts should occur between what?
- Should IDEALLY occur between a CUSP TIP and the DEPTH of a FOSSA, or between a CUSP TIP & a FLAT SURFACE, which is considered MORE STABLE.
- Contacts SHOULD NOT occur on CUSPAL INCLINES, because these are LESS STABLE
Regarding Classification of Occlusion what is the Ideal CLASS I ?
1) Ideal 1ST MOLAR relationship
2) Ideal CANINE relationship
Regarding Classification of Occlusion what is the Malocclusion of CLASS I ?
1) Ideal 1ST MOLAR relationship
2) NON-IDEAL canine relationship
3) Rotated or OVER-INCLINED teeth
Regarding Classification of Occlusion what is the Malocclusion of CLASS II (aka distal occlusion)?
1) Distally positioned FIRST MOLAR and CANINE relationships
2) EXCESSIVE ANTERIOR horizontal overlap
Regarding Classification of Occlusion what is the Malocclusion of CLASS III ?
1) MESIALLY positioned 1ST MOLAR relationship & CANINE relationship
2) NEGATIVE horizontal overlap
When a patient is in STATIC or STATIONARY the occlusal contact should occur between what?
Cusp tip & the DEPTH of an OPPOSING FOSSA called the CUSP-FOSSA OCCLUSION
In Maxillary Posterior Teeth, what are the Maxillary Cusp Name:::: Fossa or Marginal Ridge Locations?
- Lingual 1st molar ?
- Lingual 2nd molar ?
- ML 1st molar* ?
- DL 1st molar ?
- ML 2nd molar ?
- DL of 2nd molar ?
1) LINGUAL cusp of the Maxillary 1ST PREmolar = DISTAL marginal ridge or DISTAL fossa of the Mandibular 1st premolar
2) LINGUAL cusp of the Maxillary 2ND PREmolar= DISTAL marginal ridge or DISTAL fossa of Mandibular 2nd premolar
3) *MESIOLINGUAL (ML) of the Maxillary 1ST MOLAR= CENTRAL FOSSA of Mandibular 1st molar
4) DISTOLINGUAL(DL) cusp of the Maxillary 1ST MOLAR = DISTAL marginal reign or distal fossa of the Mandibular 1st molar
5) MESIOLINGUAL(ML) cusp of the Maxillary 2ND MOLAR= CENTRAL fossa of the mandibular 2nd molar
6) DISTOLINGUAL(DL) cusp of the Maxillary 2ND MOLAR= DISTAL marginal ridge or distal fossa of the Mandibular 2nd molar
What is BRUXISM?
- EXTENSIVE & PERSISTENT maximum intercuspation occlusal contacts on inclines can lead to mobility, excessive wear, fractures & other S/S of occlusal disease
- Displayed as EXCESSIVE WEAR on the OCCLUSAL SURFACE & INCISAL ridges of MANY teeth
Regarding Lateral Movements what is the left side called?
-The LEFT or OPPOSITE SIDE is termed the “NON-WORKING SIDE”
When Maxillary Cusps are positioned over Mandibular Teeth and PARALLEL to the LINGUAL groove and travels TOWARD the TONGUE what is this pathway called?
WORKING
- When Maxillary Cusps are positioned over Mandibular Teeth, The NON-FUNCTIONAL pathway is the area that what?
- The functional pathway is all the what?
- The AREA that the mandible CANNOT normally MOVE INTO
- Non-functional area is LARGER than the functional area
-Functional pathway is ALL the potential area that the mandible can move into!
When looking at a non-working movement of a MF (mediotrusive) permanent MANDIBULAR 1ST MOLAR where is it going to travel?
Across MESIAL marginal ridge of the permanent MAXILLARY 1ST MOLAR diagonal through the LINGUAL embrasure between the maxillary 2nd premolar and maxillary 1st molar
What type of mandibular movement is indicated in a moving occlusion diagram that displays a large bold arrow emanating from the CENTRAL fossa of a permanent maxillary 1ST MOLAR traveling out of the FACIAL groove?
Side: Working (AKA Lateralotrusive)
Cusp: DF cusp of mandibular 1st molar #30
What type of mandibular movement is indicated in a moving occlusion diagram that displays a large bold arrow emanating from the DISTAL FOSSA of a permanent maxillary 1ST MOLAR traveling diagonally and posteriorly over the DISTOLINGUAL (DL) cusp toward the lingual?
Movement: This is NON-FUNCTIONAL
-Because mandible can’t move towards the throat.
(Cusp: D cusp of mandibular 1st molar #19)
Regarding Border Movements on a Sagittal Plane which ones exhibit tooth contact?
Can it occur on centric relation (CR)?
1) E-T-E= Edge to Edge
2) MP= Maximum Protrusion Point
3) CR= Centric Relation
4) MI= Maximum Intercuspation
When viewing a panographic tracing of mandibular border movements of HORIZONTAL view at level of central incisors, which of the following positions will be the MOST ANTERIOR?
MAXIMUM PROTRUSION (MP)
When viewing a panographic tracing of mandibular border movements at the condylar level, on the LEFT side the long sloping arc that travels MEDIOTRUSIVELY and ANTERIORLY is called the what?
NON-WORKING condylar pathway
What is the Mandibular Lateral Translation?
- Also known as Bennett Movement & Immediate Sideshift
- First part of the lateral movement depicted when the MEDIAL POLE of NON-WORKING condyle starts to travel down the slope of the articular eminence & against the MEDIAL WALL of the FOSSA.
- Movement is exhibited as a measurement of the distance between the MEDIAL POLE of the NON-WORKING condyle & MEDIAL WALL of the GLENOID FOSSA.
If Condylar Guidance was the only vertical Determinant of Occlusion the cusp angles would need to be what?
Cusp angles would need “LESS” (inclination) THAN the angle of the articular eminence in order to avoid collision in eccentric movements.
If a patient has a loose TM Ligament on the WORKING-SIDE and a lot of distance between the medial pole of condyle & medial wall of the fossa on the non-working side what is going to occur?
CUSP heights on the NON-WORKING side MUST be SHORTER
What is Anterior Guidance?
- Anterior Guidance is a FUNCTION of the relationship between the maxillary & mandibular “ANTERIOR” teeth
- Anterior Guidance consists of the VERTICAL and HORIZONTAL overlaps as measured at the ANTERIOR TEETH
When observing Anterior Guidance for a patient if the horizontal overlap remains unchanged in the event of vertical overlap INCREASES, what happens to the anterior guidance angle?
(What can occur in Vertical Overlap Changes? )
The Anterior guidance angle also INCREASES
In a patient that exhibits both Anterior(ACF) and Posterior(PCF) controlling factors with 45 degrees each (SAME), What will be the angle of the mandibular 1ST pre-molars as they move away from the horizontal reference plane when mandible is open?
- Also 45 degrees as it moves away from the horizontal reference plane.
- This is a coordinated movement of mandible at 4 units horizontally and 4 units vertically at both PCF and ACF
Regarding Horizontal Reference Plane (HRP):
As the plane of occlusion becomes MORE NEARLY PARALLEL to the angle of articular eminence, what happens to the posterior cusps?
Posterior cusps will need to be SHORTER in order to avoid collisions with each other