4th year Flashcards
Define malocclusion
An appreciable deviation from the ideal occlusion that may be considered aesthetically or functionally unsatisfactory
5 general factors influencing occlusion
Skeletal relationship
Tooth size/arch size disproportion
Soft tissues
Genetic and developmental disorders
TMJ trauma / growth abnormalities
5 local factors influencing occlusion
Early loss of deciduous teeth
Prolonged retention of deciduous teeth
Ectopic teeth
Absent teeth
Supernumeries
Impaction
Effects of early D, E loss
Space loss as 1st permanent molars drift mesially
Effects of early C loss
Incisor midline shift as permanent incisors drift into space
Effects of early A,B loss
Minimal effect
Effect of age and early loss of deciduous teeth
Effects more severe with earlier loss
Effect of degree of crowding in the arch and early loss of deciduous teeth
Crowding exacerbates the space loss (D,E) and midline shift (C)
2 effects of the prolonged retention of deciduous teeth
Delay permanent successor
Deciduous teeth may become infraoccluded due to ankylosis
1 sign deciduous teeth may be infraoccluded due to ankylosis
Tipping of adjacent teeth first molars
2 managements of infraoccluded deciduous tooth
Monitor, almost all exfoliate naturally
Extract only if becoming completely submerged
Define hypodontia
Developmental absence of permanent teeth (excluding 3rd molars)
Define severe hypodontia
Missing 6+ teeth
Define anodontia
Complete absence
3 managements of hypodontia
Space closure
Open or maintain space then bridgework / implants / denture
Accept
2 signs of absent upper laterals
Ectopic canines
Small contralateral lateral incisors
3 managements of absent upper laterals
Space closure with fixed appliances
Bridgework/implants
4 managements of absent second premolars
Space closure (extract deciduous early)
Bridgework
Use space to treat crowding
Accept and retain Es (< age 30)
3 managements of rare absent lower central incisors
Retain As
Close space
Bridgework
Where are supernumerary teeth commonly found
80% in the anterior maxilla
5 classifications of supernumerary teeth
Coniform
Tuberculate
Mesiodens
Supplemental
Paramolar
3 clinical effects of supernumerary teeth
Delayed eruption of teeth
Crowding
Midline diastema
2 managements of supernumerary teeth
No treatment
Extract and exposure and alignment of unerupted teeth
Common location of impacted permanent first molars
Maxilla
3 managements of impacted permanent first molars
Monitor, (2/3rds) correct spontaneously, although unlikely to improve after age 8 years
Extraction of E
URA to disimpact
Common cause of impacted premolars (usually 5s)
Early loss of E
4 managements of impacted premolars (5s)
Extract 4 to allow eruption of 5
Extract 7 and distalise 6 to create space
Surgically extract 5
No treatment and review regularly
Effects of an abnormally thick upper labial fraenum
Midline diastema
A management of an abnormally thick upper labial fraenum
Conduct fraenectomy after upper canines erupt during or after space closure
3 effects of early loss of permanent 1st molars
Creates unfavourable residual space
Midline shift with unilateral loss is minimal
Overeruption of opposing first molar
A management for carious 1st molars
Extraction: best age 8-9, later the extraction increases tipping
Common cause of early loss of permanent upper incisors
Trauma
Associated with Class II Div 1, poor lower lip coverage
2 managements of early loss of permanent upper incisors
Try to save with RCT, re-implantation
If unsaveable: maintain space with prosthesis, close space orthodontically and crown lateral
Common cause of permanent upper incisor dilaceration
Trauma to deciduous predecessor, age 4-5
Sign of permanent upper incisor dilaceration
Delayed or non-eruption
Management of permanent upper incisor dilaceration
Orthodontic alignment sometimes possible
What is a peg shaped upper lateral incisor usually associated with
Ectopic canines
Define Class II Division 1 malocclusion
Lower incisor edges are palatal to the cingulum plateau of the upper incisors and the upper incisors are proclined or of average inclination, with an increased overjet (>4mm)
Prevalence of Class II Division 1 malocclusion
20-30% of all malocclusions, most common
