Ortho Exam 1 Flashcards
What is the most prevalent type of malocclusion seen in people?
Class 1.
50-55% of people are Class 1.
Where the mandible is slightly protruded (the molars are not end to end)
*Ethnic and Gender play a role too
What is the oldest specialty in dentistry?
Ortho
Who is the Father of Ortho?
Edward Angle (He characterized malocclusion Classes I, II, and III
How can over 65% of the world be BELOW average?
The “Unlawful Average”
Beware of the MEAN
Mean is the most effected by OUTLIERS.
When they say, it is all caused by GENETICS. What do they really mean
EPIGENETICS. Changing what is EXPRESSED. Not changing the actual DNA sequence.
What proves that it really is NOT genetics?
Twin studies – heritability only accounts for 50% of malocclusion
There are 5 known specific causes. What are they.
- Disturbances in embryo development
- Skeletal growth disturbances
- Muscle dysfunction
- Acromegaly and hemi-mand hypertrophy
- Dental development dysfunction
What are some SKELETAL disturbances?
Fetal molding Craniofacial syndromes fractures/injury to jaw - 5% muscle dysfunction hypertrophy/elongation
Fetal molding is associated with
Pierre Robin Syndrome
Craniofacial Syndromes include
Fetal alcohol syndrome treacher collins hemifacial microsomia crouzon's cleft lip/palate
What percent of facial asymmetries are due to jaw fracture?
5%
What kind of asymmetry is a result of jaw fracture?
PROGRESSIVE AND SEVERE
What will a condylar fracture lead to?
Some do not even affect the growth of the jaw and are NOT PROGRESSIVE and NOT SEVERE!
Describe how muscle dysfunction leads to asymmetry
Damage the motor nerve
Leads to atrophy of muscle
leads to skeletal growth disturbance
What percent of kids with facial asymmetries are due to embryo defects?
1% - thalamide was given to women a LONG TIME AGO to relieve morning sickness
What does hypertrophy or elongation lead to?
Mand prognathism
Acromegaly (big pit fossa?)
Condylar hyperplasia
What are some DENTAL disturbances?
Missing teeth malformed teeth extra teeth ectopic eruption early loss of primary teeth
What does an early loss of primary molars lead to?
crowding
Early loss of primary canines leads to
asymmetry
how can function influence form of dental arch
by changing the pattern of soft tissue pressures and affecting the equilibrium of forces against the teeth
hat kind of asymmetry is a result of jaw fracture?
PROGRESSIVE AND SEVERE
What will a condylar fracture lead to?
Some do not even affect the growth of the jaw and are NOT PROGRESSIVE and NOT SEVERE!
Describe how muscle dysfunction leads to asymmetry
Damage the motor nerve
Leads to atrophy of muscle
leads to skeletal growth disturbance
What does hypertrophy or elongation lead to?
Mand prognathism
Acromegaly (big pit fossa?)
Condylar hyperplasia
What are some DENTAL disturbances?
Missing teeth malformed teeth extra teeth ectopic eruption early loss of primary teeth
What does an early loss of primary molars lead to?
crowding
Early loss of primary canines leads to
asymmetry
how can function influence form of dental arch
by changing the pattern of soft tissue pressures and affecting the equilibrium of forces against the teeth
how do you define normal
average, esthetic, functional, acceptable
what percent of people are NORMAL AP problelms
30%
what percent are class 1
50-55%
what percent are class 2
15-20%
what percent are class 3
LESS THAN 1%
so what percent are normal occlusion?
80-85%!!!!
