Space maintainers Flashcards
What are the possible sequelae following the early loss of deciduous teeth?
1) Decreased arch length
2) Increased overbite
3) Ectopic eruption
4) Impaction
5) Crossbite formation
6) Midline discrepencies
7) Arch asymmetry
Where are primate spaces located?
Mx: Between lateral incisors and canined
Md: Between canines and first molars
what determining factors influence the sequelae following the extraction of deciduous teeth?
1) Degree of crowding.
2) Type of tooth lost. Canines result in centreline shift. Molars result in mesial drift of 6’s
3) Age of child. The earlier a tooth is lost, the greater the opportunity for drift.
what is the orthodontic significance of primary mandibular canines?
- premature loss is normally the result of large permanent incisors.
- Lateral shift often occurs with the early loss of primary canines resulting in a midline discrepency
- If primery canines have fully erupted, loss of primary inccisors do not result in loss of space
What is the consequence of the early loss of d’s.
Space loss as a result of distal drift of c’s and incisors
Space loss in Mx more than Md
What is the consequene of early loss of e’s?
Can result in a discrepency between space in the arch and tooth size esp. in Mx.
-> Early loss normally results in a mesial rotation of the Mx first permanent molars around their palatal roots.
What is the most common use of space maintainers?
To maintain space after early loss of primary first or second molars
What are the disadvantages of using a space maintainer?
1) Plaque retentive
2) May impinge on soft tissues
3) May iinterfere with eruption of adjacent teeth
4) May fracture or become dislodged and lost
(failure rate from 13 to 63%)
What are contraindications for the use of space maintainers?
1) Presence of caries or history of high caries rate
2) Poor oral hygiene
3) No alveolar bone overlying crown of erupting tooth
4) Space left is more than mesio-distal widdth of permanent succcessor
5) Repeeated examinations show no space loss
6) General lack of dental arch length
7) If there is no permanent successor and space must be orthodontically closed
what factors influence the use of space maintainers?
1) Availlible space
2) Dental age
3) Time since tooth loss
4) Bone coverage
5) Sequence of eruption
6) Abnormal oral musculature
7) Existing malocclusion
8) Patients age and cooperation
What is the average eruption speed of an erupting premolar?
About 4-6 months to move through 1mm of bone on a B/W
what are some examples of space maintainers?
1) band and loop
2) crown-loop
3) distal shoe
4) lower linguaal holding arch
5) palatal arch
6) Nance appliance
what are the advantages and disadvantages of the band and loop?
Advantages:
- little chairside time
- easily adjusted
- easy and economical to make
Disadvantages
- litttle functional replacement of missing tooth
- doesnt prevent supraeruptin of opposing tooth
when is a distal shoe indicated and how is it used?
when an E is lost prior to the eruption of the 6 to provide eruption guidance for the 6
careful radiogrphical monitoring is required and should be replaced with a band and loop once 6 has erupted
when is the lower lingual holding arch indicated?
for the Md arch during the mixed dentition if multiple posterior teeth are missing and permanent incisors have erupted
-> it basically prevents anterior movement of posterior teeth and distal movement of posterior teeth
