Occlusion 1 Flashcards
What is a realistic definition of occlusion?
The dynamic morphological and physiologic relationships among all components of the mastication system include the neuromusculature, TMJs, and teeth
What is the importance of occlusion?
Essential to both general and dental health
Mastication
Ability to speak
Enjoy food
Aesthetics
What is the position called when there is complete intercuspation of the opposing teeth INDEPENDENT of condylar position?
Maximum intercuspal position (MIP)
How would you define centric occlusion?
The occlusion of opposing teeth when the mandible is in centric relation
May or may not coincide with the MIP
An important principle in prosthodontics is that until the ________ and ________ of the _______ are precisely determined, an accurate ________ relationship cannot be verified
Position, condition, TMJ, maxillomandibular
Centric relation is ____ of tooth contact
Independent
Centric relation is a maxillomandibular relationship in which the _____ articulate in the _____ against the _____ sloped of the _________
Condyles, anterior-superior, posterior slopes, articular eminences
In the position of centric relation, the patient can make ____, ____, or ____ movements
Is this strained or unstrained?
Vertical, lateral, protrusive
Unstrained
What are the most important things to understand about centric relation (when using it in a clinical setting)
Unstrained and repeatable!
With the loss and or wear of teeth, the mandible tends to take a _________
Protrusive posture
When teeth interfere with CR and or MIP, they may be _______ , resulting in __________
Subject to overload
Occlusal trauma
What can happen if there is occlusal trauma?
Excessive wear, mobility , sensitivity or pain, fractured cusps
Nociceptor and proprioceptor signals may be increased that effect neuromuscular control - may “reroute” mandibular closure
Which arch is normally slightly larger?
Max
what are the general shapes of arch forms?
Do they have to match within a patient?
Square, ovoid, tapering
No
Anatomical abnormality may be further compromised by ____, compensatory __________, ____ beyond the occlusal ____, or loss of ______
Occlusal wear, dental-alveolar eruption, extrusion, plane, periodontal attachment
Maxillary posterior teeth have a horizontal overlap on the ____ aspect, while mand posterior teeth have a horizontal overlap on the ___ aspect
Buccal, lingual
The occlusal plane is generally _________ antero-posteriorly relative to the ___________ by approx ___ degrees
Elevated, natural horizontal plane (when pt is standing), 8-10
Normally, the max incisal edges show from ___ to ___ mm at the resting lip length with ______ showing at high smile
0-2
Free gingival margin
What forms the incisal guidance/
Max incisors overlapping mand incisors horizontally AND vertically
Degree of horizontal and vertical overlap determines the incisal guidance angle
What can cause incisors to not be aligned with patient’s facial midline?
Tooth loss, tooth size-arch length discrepancies, mesial drift, tooth agenesis, tooth wear/ altered eruption patterns
What is the plane of occlusion
What shape is the occlusal plane
An imaginary surface that theoretically touches the incisal edges of the incisors and the tips of the occluding surfaces of the posterior teeth
Curved in order to touch all aspects (listed above) simultaneously
The distance between two selected anatomical or marked points when in MIP is called the _____
What are these two points normally?
Vertical dimension of occlusion (VDO)
Tip of nose and chin
What is the postural position of the mandible when an individual is resting comfortably in an upright position?
In what state are the muscles in this position?
Rest vertical dimension (RVD)
Minimally contracted (resting !!!)
The distance between the occlusions surface of the max and mand teeth when the mand is in a specified position is called the
Interocclusal distance
The difference between the RVD and the OVD is called the _______
What’s another name for this?
Interocclusal rest distance (IRP)
RVD-OVD= IRD
Freeway space
Which curve is viewed from the lateral aspect and is curving upwards in an anterior to posterior direction?
(Incisal and cusp edges_
Curve of spee
Which curve is viewed from the coronal plane and refers to the posterior region being on the edges of this plane?
This curve is ______ and the cusps lie on this curve
Monsons /wilsons curve
Concave
Which curve is related to aligning each tooth for the maximum resistance to functional loading?
Curve of spee
The relationship between the _______ and the _______ relates to the condylar path of protrusion
If the curve passes through the ____, the posterior teeth will be ____ by the normal condylar path on its ______ condylar eminence
In simple terms, what does this mean?
Curve of spee, condylar axis
Condyle, discluded, steeper
Pt would not be able to chew!
The ____ inclination of the posterior teeth is nearly parallel with the inward pull of the _____
Which curve is this related to?
Axial, lateral pterygoid muscles
Curve of Wilson
When the teeth are aligned with the __________, it produces the greatest resistance to masticatory forces
Which curve is this related to?
Principle direction of the muscle contraction
Curve of Wilson
The inward inclination of the _________ is designed for direct access of food from the ____, with no blockage by ____ by the action of tongue
Which curve is this related to ?
Lower occlusal table, lingual, lower cusp
Curve of Wilson
Which tooth is the “key” to occlusion
Max first molars
50% of chewing on first molars
In class 1 occlusion, the ____ cusps of the max first molar is aligned directly over the _____ on the mand first molar
Mesiobuccal cusp, mesiobuccal groove
In class 1 occlusion, incisal edges of max teeth are ___ to the incisal edges of mand teeth
Incisal margins of the ________ occlude with or lie directly below the _____ surfaces of the ____
Labial
Mand incisors, palatal , max incisors
In which class of occlusion does it seem that the mandible is smaller than the maxilla
Class 2
In class 2 occlusion, mand teeth are ____ to their normal max teeth
Occlusion at least _________ to the mand 1st perm molar
Distal
Half a cusp more mesial
In class 2 occlusion, there is an ____ overlap of max incisors over mandibular
Incisal margins of the mand incisors lie ________ on the palatal surfaces of max incisors
Abnormally large
Behind the cingulum plateau
In class 2 division 1, Max incisors have a ____ inclination, also called ______
Labial, proclined
In class 2 division 2, max incisors have a ______ inclination, also called ______
Lingual, retroclined
In which division of class 2 occlusion would you see massive overjet?
Division 1
In which class 2 occlusion would you see failure of anterior lip closure due to a V-shaped upper arch?
Division 1
In which class 2 division would you see a deep overbite?
Both 1 & 2
In class 3 occlusion, which arch is larger?
Lower anterior incisors are______ or _____ to upper anteriors
Mand
In edge to edge, labial
In class 3 occlusion, incisal margins of the mand incisors lie in front of the _____ on the palatal surfaces of the max incisors
Cingulum plateau
In class 3 occlusion, mand molars are ____
Max first perm molar occludes at least _____ more ____ to the mand first perm than a normal class 1 relationship
Mesial
A half a cusp more distal
