development of dentition Flashcards
what is orthodontics?
branch of dentistry concerned with facial growth, development of dentition and occlusion, and with the diagnosis, interception and treatment of occlusal anomalies
name the 13 dental specialities
- endodontics
- periodontics
- oral surgery
- oral microbiology
- oral and maxillofacial pathology
- prosthodontics
- peadiatrics
- dental public health
- dental and maxillofacial radiology
- special care
- restorative dentistry
- orthodontics
- oral medicine
what are the 4 stages of the development of the dentition?
- newborn
- primary (deciduous) dentition
- mixed dentition
- permanent dentition
describe the newborn dentition
- upper rounded gum pad
- lower āUā shaped gum pad
- anterior open bite
- often appear skeletal class 2
what are the 3 anterior/posterior jaw relationships?
- skeletal class 1
- skeletal class 2
- skeletal class 3
describe skeletal class 1
- normal
- mandible 2-3mm posterior to maxilla
describe skeletal class 2
mandible retruded relative to maxilla (set back chin)
describe skeletal class 3
mandible protruded relative to maxilla (chin stick out)
a tooth already erupted at birth is known as?
a natal tooth
a clift lip and palate can be unilateral or bilateral, what do both of these terms mean?
unilateral - 1 sided
bilateral - on both sides
when on average does the 1st deciduous tooth erupt?
6 months
when on average will all deciduous teeth have erupted?
3 years
which deciduous teeth tend to erupt first, uppers or lowers?
lowers
in what order do the deciduous teeth erupt?
A > B > D > C > E
on average, what age do children tend to have a mixed dentition?
6-13
what are the first adult teeth to erupt?
1st premolars and incisors
what is the first adult tooth to erupt?
lower 6 or lower 1
compare permanent incisors to deciduous incisors
- permanent wider
- permanent more proclined
how long after the upper 1s erupt should the upper 2s erupt?
6 months
which teeth erupt in stage A?
- 1st premolars and incisors
which is the last tooth to erupt during stage A?
lateral incisors
what is hyperdontia?
extra teeth
what is the name of the condition which results in extra teeth?
hyperdontia/ supernumerary teeth
what is the name of the condition which results in a tooth/teeth not erupting?
hypodontia
what is the name for the condition which results in a small tooth?
microdont
what is the name for the condition which results in a large tooth?
macrodont
when the upper incisors sit behind the lowers, this is known as?
anterior cross bite or reverse overjet
when the top teeth point outwards over the bottom, its known as?
increased overjet
during stage B, in what order do the lower teeth tend to erupt?
3 > 4 > 5
when the top back teeth bite down inside the bottom back teeth this is known as?
posterior cross bite
during stage B, in what order do the upper teeth tend to erupt?
4 > 5 > 3
in order to accommodate more secondary teeth, arch length must increase, where does the arch increase from?
posterior to 1st deciduous molar
what is the name of the condition which results in the swapping of position of 2 adjacent teeth?
transposition
an unerupted tooth in the palate is known as?
palatal ectopic tooth
how is a palatal ectopic tooth moved into place?
fixed appliance
the ideal static occlusion has 6 features, name these
- incisors sit slightly proclined, lower incised edge in contact with cingulum plateau of maxillary teeth
- mesiobuccal cusp of upper permanent molar occludes with buccal groove of mandibular 1st molar
- long axis of the teeth have slight medial inclination except lower incisors
- tight approximate contacts with no rotation
- flat occlusal plane or slight curve of spee
- crowns of canines back to the molars have lingual inclination
name the 4 incisor classifications
- class I
- class II div I
- class II div II
- class III
describe incisor classification I
- lower incisor edges occlude with or lie immediately below the cingulum plateau of upper central incisors
- normal
describe incisor classification II div I
- lower incisor edges lie posterior to cingulum plateau of upper incisors
- upper central incisors proclined or of average inclination
- overjet increased
describe incisor classification II div II
- lower incisor edges lie posterior to cingulum plateau of upper incisors
- upper central incisors are retroclined
- overjet minimal
describe incisor classification III
- lower incisor edges lie anterior to cingulum plateau of upper incisors
- overjet reduced or reversed
