Ortho Flashcards
(36 cards)
Interstitial growth
growth occurs in all direction
most soft tissue
Endochondral ossification
Cartilage transformed into bone
Intramembranous ossification
bone forms from direct secretion of bone matrix WITHOUT cartilage
What type of growth in mandible/maxilla
Intramembranous
How does the mandible grow
Major contribution in length of mandible is by bone formation on caudal aspect of mandibular body and vertical ramus
Found no increase in length between mental foramen and vertical plane of rostral border of coronoid process between 4-9 months of age
By 50 days, found increase in length was completely from caudal border of mandible
How does maxilla grow
incisivo-maxillary and palato-maxillary sutue
What breed is commonly known for tight lip and when do you fix it
Sher pei
3 months
rostral vs caudal crossbite
Crossbite: mandibular tooth/teeth have a more buccal or labial position than the antagonist maxillary tooth/teeth
**Rostral crossbite: mandibular incisor tooth/teeth labial to opposing maxillary incisor
**Caudal crossbite: mandibular cheek teeth buccal to opposing maxillary cheek tooth
transposition
2 teeth switched
embrication
crowding
infraction
short tooth –partially impacted
supraclusion
tooth above occlusal level
supereruption
CEJ above normal
Interceptive Ortho
elimination of developing MAL
**extraction of deciduous
Preventative Ortho
evaluation adn elimination of condition leading to irregularities
–fibrotomy, operculectomy, extraction, ball therapy, education
Corrective Ortho
Correctiton of MAL without loss of tooth or crown
**Surgical repositioning of a tooth
**Orthognathic surgery to treat skeletal malocclusion–VPT
**Passive movement of a tooth using an inclined plane
**Active movement of a tooth using an elastic chain
6 cellular elements of PDL
undifferentiated mesenchymal cells, fibroblasts, osteoblasts, cementoblasts, giant cells
pressure of lips and tongue
lip = 5
caudal tongue = 5
rostral tongue = 10
What is the pressure tension theory
PDL is compressed in the direction the movement is taking place and stretched in the direction movement is occuring
Frontal resorption
Does not exceed capillary pressure = movement
Undermining resorption
excessive pressure = necrosis = delay in movement
What is the pressure side
direction tooth is moving
PDL compressed
What is the tension side
Away from movement
PDL stretched
What are the 6 types of movements and the pressure required
Tipping = 35-60
Translational (bodily) = 70-120
Radicular (root) = 50-100
Rotation (torsion) = 35-60
Extrusion =35-60
Intrusion = 10-20
