Occlusion Flashcards
What is occlusion?
How upper and lower teeth mechanically interact with each other: with jaw joints (TMJ), muscles, ligaments, and with periodontal tissues.
Why is occlusion important?
It is a threat connecting all disciplines in dentistry: restorative, orthodontics, periodontics, and more.
Occlusion is how we function.
Occlusion requires an understanding of ________ mechanical relationships.
three-dimensional
Why do we use the articulator?
Simulates the jaw relations and create a standardized training enviroment for studying occlusal concepts.
What is the ultimate goal for every patient?
Maintainable health and freedom from disease for the total masticatory system.
What does “healthy total masticatory system” entail? (6)
- Maintaining a healthy periodontium
- Stable TMJ
- Stable occlusion
- Healthy teeth
- Comfortable function
- Optimum esthetics.
True or False
When examining a patient, a dentist should look only at the teeth.
False
Objective is harmony between the occlusion, TMJ, and muscles of mastication.
What are some common dental complaints?
Sore teeth and gums, tooth wear, loose or missing teeth, TMJ disorders, facial pain, and esthetics.
What is the main objective of the design of the masticatory system?
Masticating and swallowing of food
What 3 components contribute to the harmony of the masticatory system?
- Stable TMJ
- Anterior teeth in harmony with the envelope of function, ups, tongue and occlusal plane
- Posterior teeth occluding with no interferences.
What 6 parts make up the anatomy of the TMJ?
- Posterior slope of the eminence
- Condyle
- disk
- Superior lateral pterygoid muscle
- Inferior lateral pterygoid muscle
- Posterior ligament
What are the two types of muscles and which one is stronger?
Elevators and Depressor.
Elevators stronger bc it is used to chew
What are the three elevator muscles?
- Masseter: allows you to clench
- Temporalis: Lifts mandible to close mouth. Mastication.
- Lateral pterygoid muscle: Moves jaw forward and backward.
What is the posterior controlling factor/condylar guidance?
TMJs (slope of eminence)
What is the anterior controlling factors/anterior guidance?
Anterior teeth (overlapping of the teeth)
What is the controlling factor for the posterior teeth?
Both TMJ and Anterior teeth
What is the curve of spee?
Antero-posterior curvature of the mandible’s occlusal alignment of the teeth, beginning at tip of lower canine, following the buccal cusps of mandibular posterior teeth and thru condyles.
Way teeth are aligned: from front to back, goes upwards.
What is compensatory curve of spee?
Maxillary teeth that corresponds to the curve of spee
Wat is the curve of wilson?
Buccal-Lingual curvature/Frontal alignment
Mediolateral curve that contacts the buccal and lingual cusp tip of each side of the arch.
The curve of wilson demonstrates the ______ inclination of lower posterior teeth, thus _____ cusp is higher than _____cusp on mandible.
Inward inclination.
Buccal cusp is higher than lingual cusp.
The curve of wilson demonstrates the ______ inclination of the upper posterior teeth, thus ______ cusp is higher than _____ cusp on maxillary.
Outward inclination.
Buccal cusp is higher than lingual cusp.
The curve of wilson affects what daily routine?
Chewing
What is the curve of sphere of monson?
Ideal curve of occlusion in which each cusp and incisal edge touches the surface of imaginary 8 inches in diameter.
What is rest position?
When not chewing, speaking or swallowing, mandible is in clinical or postural (rest) position.
Open 1-3 mm
Why is it termed “rest” position?
Believed that the muscles were at equilibrium btwn gravity and natural elasticity of the muscles and soft ligaments.
What is the “rest rest” position?
~8mm open (electromyographic rest position)
True or False
Rest position is not consistent throughout different people
True
Can change even within same patient. Therefore, inaccurate to use rest position as reference to determine vertical dimension of face.
What is Freeway space/Interocclusal space?
The difference between vertical dimension of face when mandible is at rest and when teeth are in occlusion.
What three factors affect the freeway space?
- Head and jaw position
- Stress
- Stimuli
What is Intercuspal Position (ICP)?
aka Max intercuspation, Habitual bite, Bite of Convenience. NOT Centric Occlusion
In occlusion, when jaw is closed and teeth fit together in MAXIMUM INTERCUSPATION.
*Independent of condylar position
What is Centric Relations (CR)?
Maxillomandibular relationship. Position when patient leans head back, independent of teeth.
What is retruded contact position?
Contact of a tooth or teeth along the retruded path of closure. Initial contact of a tooth or teeth on path from CR to ICP.