exam questions Flashcards
bodily movement
translation is example
system of forces - force NOT passing through center or resistance and couple
moment / force ration 10:1
single force at center of resistance (but not appliacable in the mouth)
inter-incisal angle that is larger than the norm could indicate
overbite
if larger than normal - likely because of lingual inclination of the maxillary incisors
- During transition from the mixed to the permanent dentition the anteroposterior arch length increase at the time of eruption of the premolars?
false – there is a slight decrease in BOTH ARCHES IN TERMS OF LENGTH
ARCH WIDTH INCREASE
MAX CIRCUMFERENCE INCREASE
MANDIBULAR CIRCUMFERENCE DECREASE
LEEWAY SPACE ON maxilla and mandible
maxilla 1.2
mandible 3.1
most common feature of dentla arch maloclsuionn
crowding
- the lingual arch space maintainer is usually not indicated in a patient with primary incisors
true
- an ectopically erupting tooth can cause crowding in the dental arch because it is replacing the wrong primary?
true
- guided eruption involves sequential slenderizing and extractions of permanent teeth in order to resolve crowding?
true
can include the extractions too= serial extractions- when over 10 mm of mandibular crowding exists and extractions of 4 premolars is required
conequence of molar uprighting aka
extrusion – and reduciton of the clinical crown is then often needed
- if minimal extrusion is desired during molar uprighting a straight wire with coil springs should be used?
false –use of SS wire with T loops is better if control is needed and if extrusion is not desired
- uprighting a molar that is tipped mesially by 30 degrees requires 12 months of treatment?
false
4 weeks = 10 degrees
12 months = 48 weeks
- most of the time a molar is uprighted by mesial root movement? keep in mind?
false – and distal `crownn movement can create interferences and potentially open bite – if need preping will you need endo first??
- in the case of missing maxillary lateral incisors in a patient that extraction of mandibular premolars is required, treatment is usually performed by canine substitution?
true – if class II want to try and close space and have canines become laterals
if extracting lowers – spacing is already a problem
- In order to avoid crown lengthening after forced eruption the extrusion should be performed at the rate of 1 mm per month?
false – slow extrusion – bone will follow and CLP will be needed
in rapid - 1mm / week - light forces required and if too fast can ankylosis - but this rapid will leave alveolar bone behind
rapid or slow extrusie mechanisms during forced eruption?
depends on whether coronal movement of bone is needed
if preserving bone – and bringing with = slow
stabilization period after eruption
6 months retention with passive arch wire recommende to avoid significant relapse
fiberotomy?
considered in adjunct to mechanical retention if tooth was severly rotated
helps eliminate fibers that resist the new position
wall defects and ortho
1 and 2 (hemiseptal) – moves teeth closer to the TREATED defect
craters and 3 wall defects DONT improve w/ ortho
NOT 3
tx for thick and fibrotic gingivl tissue with gummy smile
perio surgery to expose the complete crown length
- When a gingival margin discrepancy between adjacent teeth exists and the shorter tooth has a deeper sulcus the treatment of choice is excisional gingivectomy of the shorter tooth?
true – indicates gingval margin off
if gingiva was in line but shorter than adjacent - know something wrong with incisal edge
orthointrusion or gingival surgery?
evaluate labial sulcualr depth of teeth
UNIFORM = truama of incisal edges – intrude and restore
DIFFERENCES = gignival surgery
missing papilla can be caused by
divergent root shapes
abnormal tooth shape
advanced perio disease
treatment for divergent roots and no papilla
upright incisors and close space
- when the roots of maxillary central incisors are divergent, recontouring of the mesial surfaces of the crowns can be performed to correct the missing papilla?
NO – not for divergent roots but could do this for mishaped teeth
- ideally the gingival margin of the central incisors is about 1mm coronally to the lateral incisors
FALSE - 1mm apical
centrals and cuspids at same level
- in the case of congenitally missing the mandibular 2nd premolar, extraction of the primary 2nd molar is always indicated when primary molar is ankylosed and facial growth is complete
fasle – can keep the tooth there to preserve bone and recontour it
he Hawley retainer is recommended after extraction treatment?
false – this is the traditional one
the wrap around one is for extraction cases
use what after correction of midline diestams
fixed retainers
after molar uprighting alveolarbone position?
expected to be more inferior
