Lecture 11 Flashcards
what causes the most rapid loss in AP distance?
mesial tipping and rotation of perm. 1st molar and removal of primary 2nd molar
why is early loss o a primary tooth an issue?
drift of perm or other primary teeth
what 2 things makes space maintenance appropriate?
1-adequate available space
2-all unerupted teeth are normal
*if those 2 criteria aren’t there, additional intervention might be necessary
when is a distal shoe indicated?
when the primary 2nd molar is lost before 1st perm molar erupts
If the perm 1st molar is extracted before the eruption of the perm 2nd molar, is space maintenance necessary?
NO. allow the 2nd molar to drift forward
what are the two types of expansion in dental crowding?
1-skeletal expansion
2-dental expansion
what is the most common tooth to be extracted to make space for ortho?
premolars
according to contemporary extraction guidelines, with less than _____mm arch discrepancy, extraction is ______ indicated
4mm, rarely
according to contemporary extraction guidelines, with 5-9 mm arch discrepancy, _____ or _____ is a possibility
extraction or non-extraction
according to contemporary extraction guidelines, what mm of arch length discrepancy almost always calls for extraction?
more tan 10mm
what is it called when a protrusive dentoalveolar position of the max and mand arches produce a convex facial profile?
bi-maxillary protrusion
what is serial extraction?
extraction of a deciduous tooth, followed by its perm. successor to make room for coming teeth to drift mesially
*extract 1st primary molar followed by extraction of 1st premolar
what do some remark as disadvantages of extraction treatment to create space?
- detrimental facial appearance
- flat lips and retracted/sunken incisors
- narrow arch widths with large buccal corridors
what did the study find regarding attractiveness in those who had extractive and non-extractive treatment?
no difference
what did the study find regarding those who had extractions done with a combo of crowding and proclined teeth?
it had a positive effect on the pts profile
when is extraction of the mandibular incisors indicated?
if the patient has crowding with recession and bone loss
what are the 3 disadvantages of extraction mandibular incisors?
1- deeper over-bite
2-over jet
3-canine guidance may be difficult to achieve
what is the most common situation where a general dentist extracts the wrong tooth?
an ortho isn’t clear on what tooth he wants extracted
why is ortho tooth movement sometimes used for implants?
because the movement brings alveolar bone with it
what is it called when you leave a tooth in a place, or its root, to help maintain bone in the area until an implant can be place?
root burial
if you have missing lateral incisors, what do you do to get alveolar bone in that space?
allow canine to erupt (bringing alveolar bone with it) and drift mesially, then distalize it with ortho
T/F missing lateral incisors require space maintenance until implant
true
*same if using a bridge
how big is the lateral incisor compared to the central?
- 2/3 the size
- 80% length
- .5-1mm lower gingival height
what is the most commonly impacted tooth?
3rd molars
what is the 2nd most commonly impacted tooth?
max. canines
what % of max. canines impacted? ( facts)
- .8-2.4%
- 2:1 female
- 90% unilateral
are impacted canines usually palatal or buccal?
80% palatal
what are the 3 things to consider when an unerupted tooth must be surgically exposed?
1-type of surgery
2-how to attach to the impacted tooth
3-ortho mechanism to bring tooth into the dental arch
what are the 3 types of surgery for uncovering an impacted maxillary canine?
1-gingivectomy
2- apically positioned flap
3- closed eruption technique
when attaching to the tooth it is critical to bond to the ______ surface of the impacted canine
bucal surface
- or as close to it as possible or else it can come in sideways/backwards
- must have space to pull it into
T/F impacted canines should be pulled through alveolar mucosa
FALSE, should be pulled through keratinized tissue
what are the 3 thing orthos use to chose a mechanical technique to erupt max canines?
1-tooths position
2-occlusal relationship
3- xray eval
when do you refer an impacted max canine?
soon as you see mesial movement
can you treat a patient with severe root resorption with ortho?
yes
