4/4: Occlusal Considerations Flashcards
What is the baseline for evaluating patients occlusion?
Optimal functional occlusion
What are factors of occlusion?
Teeth
TMJ
Musculature
What are the goals for occlusion for direct restorations?
- Minimize trauma to supporting structures and teeth
- Preserve/maintain remaining structures including the existing
occlusal scheme - Promote longevity of the restoration
- Restore mastication to a reasonable level
How are occlusal contacts on direct restorations created?
occlusal contacts on direct restorations (amalgam alloy and composite resin restorations) are created to be in harmony with the pt’s existing occlusion (MIP & excursive movements)
What is the definition of occlusion?
The static relationship between the incising and masticating surfaces of the maxillary and mandibular teeth or tooth analogues
What is the definition of articulation?
The static and dynamic contact relationship between occlusal surfaces
of teeth during function
What are teeth relations in?
Optimal functional occlusion
- in stationary position
- during excursive movements
What is the stationary position for posterior teeth?
Multiple, even, bilateral, and simultaneous occlusal contacts with the mandible in the CR position, are the most desirable
How are posterior teeth loaded?
Mainly along the long axis of the tooth (axial loading)
What is axial loading?
Forces are directed over the long axes of teeth
What are teeth and their periodontal ligaments best designed for?
to absorb forces along the long axes
What are failures to achieve axial loading?
- Forces could eventually cause cracks, fractures, and wear on teeth
- Trauma to supporting structure: periodontal ligament and surrounding
bone - Possible trauma to the
temporomandibular joints (TMD)
What is the stationary position for anterior teeth?
Anterior teeth should have LIGHTER occlusal contacts when the posterior teeth are in occlusion.
Since the anterior teeth are not loaded axially, they are not able to withstand high loads
What are optimal occlusal relationships in excursive movements?
- Canine Guidance and
- Anterior Guidance
Describe canine guidance for right lateral movement
If in excursive movements, canine guidance and anterior guidance
are not present, then __________ are present
Occlusal interferences
What is an occlusal interference?
an unwanted (or premature) interocclusal contact
What are the two philosophies of interocclusal contacts?
- Cusp-Fossa contacts
- Cusp-Marginal Ridge contacts
What is cusp fossa philosophy?
Each functional cusp occludes in a fossa
of the opposing tooth
* Tooth to Tooth arrangement
* Used when restoring both
opposing quadrants of teeth
What is the cusp-marginal ridge philosophy?
Each Functional cusp contacts the marginal ridges
of opposing pair of teeth or fossae of opposing teeth
* A one tooth to two teeth arrangement
* The majority of natural dentitions have this type
* Commonly used for single restorations
Compare the cusp-fossa and cusp-marginal ridge philosophies
What does the cusp-marginal ridge occlusal relationship allow for?
cusps to occlude onto marginal ridges and some others to occlude
into fossa
What does the cusp-fossa relationship allow?
Only for each cusp to occlude into one fossa
What are the four inclines present on all cusps?
Facial
Lingual
Mesial
Distal
Where are occlusal contacts in operative dentistry optimal?
Where are occlusal contacts in operative dentistry not optimal?
What do maximum intercuspation options when teeth are not ideally positioned create?
Create a plateau, halfway up a cuspal incline, that is perpendicular to the long axis of the tooth, to serve as a cusp seat
- These areas are not in the “normal” location of cusp seats, they will still create long axis forces on the teeth
