| Field | Value |
|---|---|
| ID | OA-0098 |
| Type | anchorage |
| Category | anchorage |
| Fixed/removable | fixed (TAD-anchored) |
| Primary function | anterior dental intrusion; deep overbite correction |
| Malocclusion target | deep overbite |
| Uses TADs | yes — 2–4 buccal TADs |
| Period | modern |
| Status | current |
Deep overbite correction traditionally requires either posterior extrusion (bite plate, brackets) or genuine anterior intrusion. TAD-based anterior intrusion achieves true incisor intrusion by anchoring directly to the bone, bypassing the dental arch as the reaction unit. Two TADs placed between the roots of the upper canine-first premolar or lower canine-first premolar provide direct intrusion anchorage. A sectional wire or NiTi coil spring delivers ~60 g of intrusive force per side to the anterior teeth. This produces genuine incisor intrusion with no extrusion of the posterior teeth — superior to bite plate mechanics where posterior eruption is the primary mode.
Buccal TADs are placed in the attached gingiva between canine and first premolar roots. An intrusion auxiliary (sectional 0.016 × 0.022 SS or TMA, or NiTi coil spring) is attached from the TAD to the anterior tooth bracket. This delivers a continuous ~60 g intrusive force. The TAD provides absolute anchorage — no posterior extrusion occurs. The anterior segment intrudes by 2–5 mm depending on the treatment plan. Indirect anchorage can be established by ligating the posterior brackets to the TADs passively to prevent mesial drift.
Deep overbite (≥4 mm); cases where posterior extrusion is not desired (Class II hyperdivergent with deep bite); anterior open bite with excessive incisor extrusion (intrude to close); cases with gummy smile requiring genuine incisor intrusion; combination with comprehensive fixed appliances.
Adequate root divergence between canine and first premolar required for safe TAD placement; adjacent root proximity on CBCT must be confirmed; intrusion of multiple teeth simultaneously requires careful force distribution; not appropriate if deep bite is due to mandibular skeletal deficiency (requires orthognathic surgery).
The intrusion auxiliary may be prefabricated (NiTi coil spring) or fabricated chairside from TMA wire. No specialized lab component is required — the TAD and spring are entirely clinician-placed.
for open bite correction
intrusion using TADs
design
molar level delivering intrusive force to anterior segment
anchorage for pure intrusion without posterior extrusion
segment acts independently on anteriors
controlled, low-friction anterior intrusion
anterior brackets — most common clinical approach
PMC](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10046359/)
Dentistry](https://decisionsindentistry.com/article/clinical-uses-temporary-anchorage-devices/)
Wiley](https://onlinelibrary.wiley.com/doi/10.1155/2020/5213936)
deep overbite, force calibration.