Ortho - Lecture 7: Problems in Mixed Dentition Flashcards
Irregular and malaligned teeth in the early mixed dentition arise from what two major causes?
Interferences w/ eruption
Lack of space
When determining if you need to maintain space or regain space, what should you do?
Space analysis
Amount of space available vs. amount of space needed
Space analysis
How do you figure out space available?
Measure arch length
How do you figure out space needed?
Add widths of each tooth
How do you figure out space needed if a tooth is unerupted?
Estimate with:
X-Rays
Proportionality tables
Combo of both
The difference between the size of the larger primary molars and the smaller permanent premolars
Leeway Space (e space)
What is the Leeway Space in the maxilla (per side)?
1.5mm
What is the Leeway Space in the mandible (per side)?
2.5mm
___________ is required if there is not enough space or if succedaneous teeth are missing
Regaining
Up to _____ mm of space can be re-established in a localized area with relatively simple appliances and a good prognosis
3mm
More than ______ mm discrepancy between the amount of space available for the teeth and the amount of space required is a ________ problem
3-4mm; severe
Where is space easier to regain, the maxillary or mandibular arch?
Maxillary
Why is it easier to regain space in the maxillary arch?
Increased anchorage for removable appliances due to palate
Headgear
How can permanent maxillary 1st molars be tipped distally to regain space?
Fixed or removable appliance
How can molars be bodily moved to regain space?
Fixed appliance only
Because molars tend to tip forward and rotate mesio-lingually, distal tipping for ______ mm of space regaining is often satisfactory
2-3mm
What are 4 appliances to help regain space in the maxilla?
Hawley retainer w/ fingerspring
Pendulum appliance
Distal Jet appliance
Headgear
Which appliance to help regain space in maxilla?
Removable retainer worn to regain space by tipping the permanent first molar distally
Hawley retainer w/ fingerspring
Which appliance to help regain space in maxilla?
After space regaining, the space should be maintained with a band and loop or lingual arch
Hawley retainer w/ fingerspring
Which appliance to help regain space in maxilla?
Fixed appliance used to distalize molars bilaterally
Pendulum appliance
Which appliance to help regain space in maxilla?
Gains anchorage from the palate but uses helical springs to supply the distalizing force
Pendulum appliance
Which appliance to help regain space in maxilla?
Fixed appliance used to distalize molars unilaterally or bilaterally
Distal Jet appliance
Which appliance to help regain space in maxilla?
Uses palate as anchorage
Distal Jet appliance
Which appliance to help regain space in maxilla?
Most effective and straightforward method to move molars distally
Headgear
Which appliance to help regain space in maxilla?
Advantage: no reciprocal incisor protrusion
Headgear
Which appliance to help regain space in maxilla?
Disadvantage: compliance (minimal of 14 to 16 hours per day required)
Headgear
Regardless of the method used to regain space, a space maintainer is required after adequate space has been
established. What is the preferred space maintainer?
Fixed space maintainer
Mandibular space regaining is not as effective as maxillary space regaining because appliances are more ___________ and prone to breakage
fragile
Mandibular space regaining appliances do not fit as well and there is not palatal anchorage support.
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