| Field | Value |
|---|---|
| ID | OA-0096 |
| Type | distalizer |
| Category | distalizer |
| Fixed/removable | fixed (TAD-anchored) |
| Primary function | maxillary molar distalization via pendulum springs |
| Malocclusion target | Class II molar relationship |
| Inventor | Modified from Hilgers pendulum (1992) |
| Uses TADs | yes — 2 mid-palatal TADs |
| Period | modern |
| Status | current |
The pendulum appliance (Hilgers, 1992) uses TMA wire springs shaped like a pendulum to deliver distal force to the maxillary molars via a Nance acrylic button resting on the anterior palate. The TAD-supported version replaces the Nance/premolar anchorage with 2 mid-palatal TADs, providing pure skeletal anchorage. This eliminates the unwanted mesial movement of the premolars and anterior proclination that occur with the conventional tooth-supported design. The TMA pendulum springs remain the active element, delivering a controlled distal tipping force on the molars.
Two palatal TADs anchor the central framework. TMA (titanium-molybdenum alloy) pendulum springs extend from the framework and engage first molar bands via sheaths. Spring activation delivers a distal and slightly occlusal force on the molars. The pendulum design produces primarily distal tipping of the molar crowns with some distal root movement. After distalization, uprighting bends are incorporated to reduce tipping. Because anchorage is skeletal, no mesial drift of premolars occurs.
Class II molar correction; adolescents and adults requiring molar distalization; cases where the original pendulum produced unacceptable premolar mesial drift; practices familiar with pendulum spring mechanics who want to add skeletal anchorage; combined with full fixed appliances.
TMA springs may fatigue over long treatment times; molar tipping is greater than bodily movement; impacted third molars must be managed; TAD placement requires adequate palatal bone.
Springs are bent from TMA wire to the pendulum configuration and pre-activated to the prescribed force. The framework is fabricated to the palatal model with TAD attachment points. Activation range is calibrated to the molar distalization distance needed.
without TADs
version for comparison
simultaneous distalization and transverse expansion
anterior anchorage loss and tipping of premolars
preactivated wire spring
unilateral Class II correction
Products](http://www.orthodonticproductsonline.com/2014/06/maxillary-distalization-tads/)
MDPI](https://www.mdpi.com/2076-3417/14/23/11333)
pendulum, spring mechanics, fabrication.