Lab 2.2 Classifications of Malocclusion (Excluding those already mentioned in 2.1) Flashcards
Aids in the diagnosis and treatment planning of malocclusions by orienting the clinician to the type and the magnitude of the problems and possible mechanical solutions to the problems.
Classification
The relation of maxillary and mandibular teeth when the jaws are closed in a centric relation without strain of musculature or displacement of condyles in their fossae.
Occlusion
It is a pre-conceived theoretical concept of occlusal structures and functional relationships that include idealized principles and characteristics that an occlusion should have.
Ideal occlusion
It is some deviation from that of ideal but is aesthetically acceptable and functionally stable for the individuals.
Normal occlusion
The upper and lower teeth fit nicely and evenly together with the least amount of destructive interferences.
Normal occlusion
Defined as a condition where there is departure from the normal relation of the teeth to the other teeth in the same dental arch or teeth in opposing arch.
Malocclusion
An occlusion in which there is a malrelationship between the arches in any of the planes of the spaces or in which there are anomalies in tooth position beyond the limit of normal.
Malocclusion
It is a condition that reflects an expression of normal biologic variability in the way the maxilla and mandible teeth occlude
Malocclusion
The term ‘malocclusion’ was coined by?
Edward Angle
Key 1
The mesio-buccal cusp of the upper first molar should occlude in the ______ between the mesial and medial buccal cusp of the lower first molar.
Key 2
The gingival part of the long axis of the crown must be _____ to the occlusal part of the line
Key 3
The maxillary incisors exhibit a ________ crown inclination while the mandibular incisors show a very mild ______ crown inclination. The maxillary and mandibular posteriors have a ________ crown inclination.
Key 4
Normal occlusion is characterized by ________ of any rotation.
Key 5
To consider an occlusion as normal,
there should be ___________ between adjacent teeth.
Key 6
A normal occlusal plane according to Andrews should be _______, with the curve of Spee not exceeding _________.
- groove
- distal
- postive; negative; negative
- absence
- tight contact
- flat; 1.5 mm
3 types of malocclusion?
- Intra-arch
- Inter-arch
- Skeletal
It include variations in individual tooth position or a group of teeth within an arch.
Intra-arch malocclusion
It compromise of malrelationship between two teeth or group of teeth of one arch to another arch.
Intra-arch malocclusion
It involves the apical upper and lower bony bases.
Skeletal malocclusion
Intra-arch malocclusion include? (3)
- Abnormal inclination.
- Abnormal displacement.
- Spacing and crowding within same arch.
This is a condition where the crown of tooth is tilted or inclined mesially.
Mesial inclination.
Refers to a condition where the crown is tilted or inclined distally.
Distal inclination
This is an abnormal lingual or palatal tilting of tooth.
Lingual inclination / retroclination
This refers to labial or buccal inclination of tooth.
Labial inclination / proclination
This refers to a tooth that is bodily moved in a mesial direction towards the midline.
Mesial displacement
This refers to a tooth that is bodily moved in a distal direction away from the midline.
Distal displacement
This is a condition where the entire tooth is displaced in lingual direction
Lingual displacement
This is a condition where the tooth is displaced bodily in labial or buccal direction.
Buccal displacement
This is a condition in which a tooth that has over erupted as compared to other teeth in the arch.
Extrusion / supra-version
Refers to a tooth that has not erupted enough as compared to other teeth in the arch.
Intrusion / infra-version
This describes a tooth that has rotated around its long axis so that the distal aspect is more lingually placed.
Disto-lingual / Mesio-buccal rotation
This is a condition where the tooth has rotated around its long axis so that the mesial aspect is more lingually placed.
Mesio-lingual / Disto-buccal rotationThis term describes a condition where two teeth have exchanged places.
This term describes a condition where two teeth have exchanged places.
Transposition
These inter-arch malocclusions can occur in the? (3)
Sagittal, vertical, transverse plane
_______ malocclusion:
- The forward placement of a jaw is called as ________ while more backward placement of jaw is called as __________.
- sagittal plane
- prognathism
- retrognathism
- The abnormal variations in vertical measurement of jaws can affect the lower facial height.
- These malocclusions include deep bite and open bite where an abnormal vertical relation exists between the teeth of upper and lower arch.
Vertical plane malocclusions
- It is a result of narrowing or widening of jaws.
- Can be described as narrow maxilla, wide mandible etc.
Transverse plane malocclusions
This is a condition where the lower arch is more forwardly placed when the patient bites in centric occlusion.
Pre-normal malocclusion
This is a condition where the lower arch is more distally placed when the patients bite in centric occlusion.
Post-normal malocclusion
It includes various types of crossbites.
Transverse plane malocclusions
- They are the malrelations of apical bases of upper and lower arch.
Skeletal malocclusions
Skeletal malocclusions may be due to? (4)
- Abnormal size
- Abnormal shape
- Abnormal relation to the skull - Abnormal relation to each other
Another malocclusion that is most often categorized under class I is ___________________ where the patient exhibit normal class I molar relationship but the dentition of both the upper and lower arches are forwardly placed in relation to facial plane.
bimaxillary protrusion
The mesiobuccal cusp of maxillary 1st molar occludes the interdental space between mandibular 1st and 2nd molars.
Class III (Angle’s classification)
It is of genetic origin and is due to:
- Excessively large mandible
- Forwardly placed mandible
- Smaller than normal maxilla
- Retro positioned maxilla
- Combination of above causes
The lower incisor tend to be lingually inclined.
True / Skeletal Class III
It is produced by forward movement of mandible during jaw closure; thus it is also called postural or habitual class III malocclusion.
Pseudo Class III
It is due to:
- Presence of occlusal prematurities may deflect the mandible forward.
- In case of premature loss of deciduous posteriors.
- A child with enlarged adenoids.
Pseudo Class III
The distobuccal cusp of the maxillary 1st molar lies within the buccal groove of mandibular 1st molar.
Class II
Angle’s Class II:
DIVISION 1:
- Proclined upper incisors with a resultant increase in ______.
- A deep incisor _____ can occur in anterior region.
- Presence of abnormal muscle activity.
- The upper lip is usually hypotonic, short and fails to form a ________.
-The lower lip cushions the palatal surface of upper teeth called as “_______”.
- The muscle imbalance is produced by a hyperactive _______ and _________ and an altered tongue that accentuates the narrowing of upper dental arch (V shape).
DIVISION 2:
- Presence of ________ inclined upper central incisors and ________ tipped lateral incisors overlapping the central incisors.
- overjet
- overbite
- lip seal
- lip trap
- buccinator and mentalis
- lingually; labially
Buccal placement of a tooth or group of teeth.
Buccocclusion
Lingual placement of tooth or group of teeth.
Linguocclusion
When a tooth or group of teeth have erupted beyond the normal level.
Supraocclusion
When a tooth or group of teeth have erupted below the normal level
Infraocclusion
Mesial to normal position
Mesioversion
Distal to normal position.
Distoversion
Transposition of two teeth.
Transversion
Abnormal axial inclination of a tooth.
Axiversion
Rotation of a tooth around its long axis.
Torsiversion
This classification is based on etiology.
Bennett’s classification
Abnormal position of one or more teeth due to LOCAL CAUSES.
Class I (Bennett’s)
Abnormal formation of a part of or whole of either arch due to DEVELOPMENTAL DEFECTS of bone.
Class II (Bennett’s)
Abnormal relationship between upper and lower arches, and between either arch and facial contour and correlated abnormal formation of either arch.
Class III (Bennett’s)
It is a craniometric classification.
Simon’s classification
Classification was based on abnormal deviations of dental arches form their normal position in relation to these three anthropometric planes.
Simon’s classification
It connects the margin of the external auditory meatus to the infra-orbital margin.
Frankfort’s horizontal plane
This plane is perpendicular to the Frankfort plane, dropped down from the bony orbital margins directly under the pupil of the eye.
Orbital plane
According to Simon, this plane should pass through the DISTAL THIRD OF UPPER CANINE called as Simon’s law of canine.
Orbital plane
This plane is used to describe malocclusion in sagittal or antero-posterior direction.
Orbital plane
It is used to describe malocclusion in transverse direction.
Mid-sagittal plane
- Considered transverse and vertical discrepancies.
- Evaluated crowded and arch asymmetry.
- Incisor protrusion.
- Influence of dentition on profile.
Ackerman and Proffit’s Classification
Ackerman and Proffit’s Classification is based on 5 characteristics, which are?
- Alignment
- Profile
- Transverse relationship
- Class
- Bite depth
Also known as Incisor Classification.
Ballard’s classification
Who developed the premolar relationship?
Katz
Most anterior upper premolar fits exactly into the embrasure created by distal contact of most anterior lower premolar.
Premolar Class I
Most anterior premolar is occluding MESIAL embrasure created by distal contact of most anterior lower premolar.
Premolar Class II
The most anterior premolar is occluding DISTAL of the embrasure created by the most anterior lower premolar.
Premolar Class III
