Occlusion Flashcards
Functional Occlusion
Occurs during mastication and swallowing
Static Occlusion
Jaws are closed - centric occlusion
Mandibular Movements: depression
Open
Mandibular Movements: elevation
Closed
Mandibular Movements: protrusion
Forward
Guided by incisors
Mandibular Movements: retrusion
Backward
Mandibular Movements: lateral
Left-Right
Guided by canines
One side working, other side balancing
Centric Occlusion
“Habitual occlusion”
“Natural bite”
Usual or routine, maximum contacts
Centric Relation
Relationship of max/mand when condyle is rearmost in glenoid fossa - TMJ
Overjet
Max teeth overlap mand HORIZONTAL
1-3mm is normal
Overbite
Max teeth overlap mand VERTICAL
Incisal/middle/cervical
Normal/slight/severe
Intercuspation
Lingual cusps of max occluding w mand
Interdigitation
“antagonists”
Mesognathic
Even facial profile where max teeth slightly overlap mand
Molar Relation: normal
First molars - mand MB groove aligns w max MB cusp
Canine Relationship: normal
max occludes w distal half of mand + mesial half of 1st mand premolar
Retrognathic
Maxilla protrudes
Mandible appears weak/retruded
Molar Relationship: Class II
MB groove is distal to MB cusp by a premolar
Canine Relationship: Class II
Distal of mand is distal to the mesial surface of max by a premolar
Class II, Division 1
Maxillary incisors protruded (overjet/overbite)
Class II, Division 2
Max incisors retruded
Tilted toward mand incisors
Prognathic
Prominent lower lip/mandible protruded
Molar Relationship: Class III
MB groove mesial to MB cusp by a premolar
Canine Relationship: Class III
Distal of mand is mesial to mesial of max by a premolar
Labioversion
individual teeth positioned labial to normal (anterior)
Linguoversion
individual teeth positioned lingual to normal
Buccoversion
individual teeth positioned buccal to normal (posterior)
Surpaversion
individual teeth elevated above line of occlusion
Torsoversion
individual teeth rotated/turned
Infraversion
individual teeth depressed below line of occlusion
Crossbite
Quadrant of teeth that are facial or lingual to normal position
Edge to Edge
Anterior incisor edges occlude instead of overlap
End to end
Posterior cusps occlude
Curve of Spee
Anterior - posterior curve
Curve of Wilson
Mesial - lateral curve
Lateral Occlusion
Guided by canines
Canines should be only teeth occluding “canine rise”
Protrusive Occlusion
Guided by incisors
All 8 anteriors in contact
Functional Contacts
Normal contact during chewing/swallowing, momentary
Parafunctional Contacts
Tooth contact that directs the mandible away from CO
Outside range of normal function
Parafunctional habits
Clenching Bruxism Tongue thrusting Sucking Lip incompetence Mouth breathing
Premature occlusion
Tooth that contacts first as jaw closes in CO
Contacts when should be disengaged
—> leads to traumatic occlusion
Traumatic Occlusion
Tooth mobility Sensitivity Migration Wear facets Open contacts
Primary Occlusion: canines
Same as permanent
Primary Occlusion: molars
Terminal plane relationships:
Mesial step or flush terminal plane
Mesial Step
PRIMARY mand. 2nd molar is mesial to the maxillary 2nd molar
Flush Terminal Plane
PRIMARY max and mandibular 2nd molars are end-to-end
Distal Step
PRIMARY mand 2nd molar is distal to maxillary 2nd molar
Not ideal
