| Field | Value |
|---|---|
| ID | OA-0099 |
| Type | anchorage |
| Category | anchorage |
| Fixed/removable | fixed (TAD-anchored) |
| Primary function | molar uprighting / de-impaction |
| Malocclusion target | mesially tipped molars; impacted second molars |
| Uses TADs | yes — 1–2 TADs per quadrant |
| Period | modern |
| Status | current |
Mesially tipped or impacted second molars — most often the mandibular second molar after extraction of the first molar or due to impaction against the third molar — are effectively uprighted using TAD anchorage. A TAD placed distal to the tipped molar (often after third molar extraction) provides an absolute anchor for a coil spring or elastic that delivers a distalizing and uprighting moment. Mean treatment time is approximately 10 months with no major complications. The TAD eliminates the anterior anchor loss that occurs with conventional uprighting springs anchored to premolars or canines.
A TAD is placed between the mandibular canine and first premolar area, or distal to the third molar after its extraction. A coil spring connects the TAD to an eyelet bracket directly bonded to the tipped second molar crown. The spring delivers a distalizing force that creates a tipping moment — the molar crown tips distally while the root moves mesially, uprighting the tooth. Once upright, the space previously occupied by the tipped tooth is available for bracket placement and definitive orthodontic treatment. A restorative prosthesis for the missing first molar can then be placed.
Mandibular second molar impacted against the third molar; mesially tipped mandibular second molar after extraction of the first molar; maxillary second molar tipped toward a first molar extraction space; cases where uprighting spring mechanics fail due to poor anterior anchorage.
CBCT required to confirm adequate bone for TAD placement and molar root geometry; after uprighting, some molar tipping (not bodily movement) may remain — may need uprighting bend in the archwire; if third molar is still present, extraction typically precedes or accompanies TAD-based uprighting.
No specific lab appliance required for the basic TAD uprighting mechanism — clinician-placed TADs and chairside bonded brackets. In complex cases, a custom uprighting spring may be fabricated by the lab from TMA or SS wire.
anterior anchor loss
arm
site (different direction)
TPA; tooth-borne anchorage rather than TAD
molar; TAD or anterior teeth provide anchorage
segmented archwire system
molar band to combine uprighting + space opening
tipped molar; elastic or spring directly from TAD to molar hook
PMC](https://pmc.ncbi.nlm.nih.gov/articles/PMC9267505/)
Wiley](https://onlinelibrary.wiley.com/doi/abs/10.1002/9781119513636.ch40)
molar impaction, clinical outcomes.