Orthodontics
Anomalies
of
Teeth
Groups of teeth
Jaws
Intermaxilary relation
Anomalies of
tooth number
• Hypodontics (hypodontia) – the tooth (or teeth are
missing)
• Third molars (if third molars are missing –it is not
hypodontia), second premolars, upper lateral incisor
• Hyperodontics (hyperodontia) supernumerary teeth
• Anodontics (anodontia
Diastema
Anomalies
of tooth size
(dimension)
Microdontics (microdontia)
– small teeth, spaces
between teeth
Macrodontics
(macrodontia) – big teeth,
crowding
Anodontia od 12, cone tooth 22
Anomalies
of tooth
position
Inclination
Rotation
Transposition
Infraoclusion
Supraoclusion
Vestibular, oral eruption
Diastema
Inclination
Mesioinclination: the
long axix is inclinated
mesially
Distoinclination: the
long axix is inclinated
distall
Inclination
Inclination
Rotation
The tooth is rotated around the
long axis:
-Mesiorotation – the vestibular
surface is rotated mesially
- Distorotation – the vestibular
surface is rotated distall
Rotation
Rotation
Supraocclusion
Infraocclusion
Vestibular eruption
Diastema
Protrusion
The tooth is
declinated
vestibulary
Retrusion
The tooth is
declinated orally
Transposition
• The position of teeth is exchanged
Spacing – trema, diastema
Crowding
Intermaxillary
relationships • Key of occlusion acc to Angle – position of
first molars – maxillary and mandibulary
Key of
occlusion
acc. to
Angle
Normoocclusion
(normoocclusia)
Distoocclusion – mandible is in
posterior position (distoocclusia)
Mesiooclussion – mandible is in
anterior position (mesioocclusia
Angle class I
• The mesiobuccal cusp of the maxillary first
molar lies in the mesiobuccal groove of the
mandibular first molar, but the other teeth
may have other anomalies such as spacing,
crowding, open bite etc
Angle class II
The mesiobuccal cusp of the
upper molar is situated anterior
to the mesiobuccal groove
Two subdivisions exist: n Division
1 (II/1) --> Anterior teeth
protrude, increased overjet n
Division 2 (II/2) --> Central
incisors retrude, lateral incisors
protrude
Angle class II.
Angle class III.
• The mandible is in anterior popsition
Positive overjet Negative overjet
Anterior cross bite
Deep bite Open bite
Mesioocclusion, posterior cross bite
Prevention of orthodontic anomalies
Prevention of orthodontic anomalies