orthodontics need to know Flashcards
give occlusal presentations of a digit sucking habit
proclined upper incisors
retroclined lower incisors
anterior open bite/incomplete open bite
posterior crossbite
narrower upper arch
how is the posterior dentition affected by a digit sucking habit?
narrow arch created by masster muscle constantly pushing upper posterior teeth palatally
posterior crossbite can then be observed when narrowed upper arch meets lower arch
what are common causes of an unerupted central incisor?
- congential absence
- unerupted supernumerary preventing eruption
- pathology
list steps to help with diagnosis of unerupted central incisor
take detailed histroy- check for environmental/hereditary factors and history of trauma
intraoral exam- sequence of eruption, presence of contralateral tooth, rotation/displacement of other teeth in region
check for presence of labial/palatal swellings which may indicate presence of the tooth
take a radiograph
what are the 4 principles for an unerputed central incisor?
remove supernumerary/deciduous if present
create space for the tooth
monitor for at least 18 months
expose the incisor if it doesnt erupt on its own and place a gold chain- orthodontic traction
what is the treatment of an unerupted central incisor?
removal of any obstruction with creation of space
removal of obstruction only
surgical intervention- incision
orthodontic traction
define local malocclusion
localised problem with either arch (1/2/3 teeth)
can be due number, size/form, position, soft tissue or a pathology
ectopic, impacted, missing, trauma, habits, supernumeracy
what are the types of supernumerary teeth?
conical
tuberculate
supplemental
odontome
what are examples of variation in tooth number
supernumary teeth
hypodontia
Retained primary teeth
early loss of primary teeth
unschedules loss of permanent teeth
what are the types of supernumary teeth
conical
tuberculate
supernumary
odontome
what are 2 ways to assess AP skeletal pattern
direct Palpation of skeletal bases
visual assessment of the relationship between soft tissue A and soft tissue B
what are possible non-skeletal factors that can because class 2 div 2 occlusion
lip trap
digit sucking
crowding
what appliance can be used to correct class II div 2 malocclusion
functional appliance - twin block
how does mandibular growth occur
growth occurs at condylar cartilage
growth occurs by surface remodelling ( resorption and deposition of bone)
results in increase in height of the ramus and increase in the length of the dental arch to accomodate teeth
growth is downwards and forwards
pt w history of trauma presents unhappy with appearance of front tooth. what part of the physical exam is important?
palpation of the labial sulcus
what radiographs are used for an 8 year old boy with previous trauma to central incisor?
periapical
anterior occlusal **of maxilla **
how can you assess vertical skeletal relationship?
- assess relationship of frankfort and mandibular plane angles
- lower anterior face hieght compared to total anterior face height
how should the patients head be positioned during clincical assessment?
frankfort plane parallel to floor to avoid error in assessment
define class III incisor malocclusion
lower incisors occlude/would occlude anterior to cingulum of upper incisors
define class I incisor relationship
the lower incisor edges occlude with or lie immediately below the cingulum plateau of the upper central incisors
define class II incisor relationship
the lower incisor edges lie posterior to the cingulum plateau of the upper incisors
define class II division 1 incisor relationship
the upper incisors are proclined or of average inclination and there is an increase in overjet
define class II division 2 relationship
the upper central incisors are retroclined. The overjet is usually minimal or may be increased
how would you describe a patient with class III occlusions skeletal relationship in terms of growth and development
maxillary hypoplasia
mandibular prognathism
mahow would you describe a patient with class II occlusions skeletal relationship in terms of growth and development
maxillary prognathism
mandibular hypoplasia
define incompetent lips
lips dont meet at rest when the mentalis muscle is relaxed