Ortho Flashcards
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
Force
load applied to an object that tends to move it in to a different place
Eruption of deciduous teeth dogs and cats
Dog = I-3w, C-3w, PM-4-12w, M-X
Cat = I-2w, C-3w, PM-3-6w, M-X
Eruption of permanent teeth dog and cat
Dog = I-3-5m, C-4-6m, PM-4-6m, M- 5-7m
Cat = I-3-4m, C-4-5m, PM-4-6m, M-4-5m
When do apices close dog
7 mo – M1 and max I1 and I2 closed ; mand PMs also closed
8 mo – I3 and max PMs closed
10 mo – canines closed
(maxillary -9.5mo)
When do apices close cat
7 mo – M1 closed;
all others open
8mo – almost complete closure of PMs in mand
9 mo – all PMs closed
10 mo – max canines closed
11 mo- all closed
When do teeth start developing
25 days
What is anchorage ratio
2:1
Ex: force of tipping is 35-60 then anchorage must be 70-120
What is hyalinization
required for active force movement via bone resorption
Most common breed for caudal crossbite, lanced canines, rostral corssbite
caudal - collies
rostral - collies
lanced - shelties
Simple vs complex retention period
Simple - 2-6 weeks
complex - 4-12 weeks
What breeds are more common for ankyloglossia and macroglossia
macro - mini schnauzer
Anky - Anatolian
Re-epitheliazation of gingiva takes how long
7-10 days
