| Field | Value |
|---|---|
| ID | OA-0155 |
| Type | functional |
| Category | functional |
| Fixed/removable | semi-fixed (buccal tube insertion; patient-removable for hygiene) |
| Primary function | arch length development; lower molar distalization; Frankel effect |
| Malocclusion target | mild mandibular crowding; Class I with arch length deficiency; lower anterior crowding |
| Inventor | various (developed mid-20th century) |
| First year | 1960s |
| Period | modern |
| Status | current |
| Wire gauge | 0.045″ or 0.051″ SS wire; acrylic or plastic shield anteriorly |
| Uses TADs | no |
A lip bumper is a wire-and-shield appliance that inserts into buccal tubes on the lower first molar bands and holds a smooth acrylic or plastic shield 1.5–2 mm in front of the lower anterior teeth. By transmitting the resting pressure of the lower lip away from the teeth to the molars, it simultaneously reduces pressure on the lower anteriors (allowing some labial tipping and arch development) and applies a distal force to the molars through the buccal tubes. The net effect is modest arch perimeter increase, useful in Phase I treatment to avoid premolar extraction in borderline cases.
At rest, the lower lip exerts approximately 100–300 g of pressure on the anterior teeth. The lip bumper intercepts this force and redirects it through the wire arms to the molar buccal tubes. This produces: (1) labial tipping of the lower incisors (increased anterior arch perimeter); (2) distal force on the lower molars (molar distalization or uprighting); (3) a mild widening effect from cheek pressure relief. The magnitude of change is modest — typically 1–3 mm of arch length gain — but clinically significant enough to avoid extraction in selected borderline cases.
Phase I treatment for mild lower arch crowding where extraction would otherwise be considered; lower arch development in early mixed dentition; uprighting and distalizing lower first molars; cases where eliminating lip muscle hyperactivity is part of the treatment plan; combined use with other Phase I appliances (RPE + lip bumper). Best results in growing patients (mixed or early permanent dentition). Not a substitute for comprehensive orthodontic treatment — an adjunct.
Minimal arch development effect in adults — sutures and bone do not respond the same way. Does not create skeletal change — purely dentoalveolar. Patient compliance is necessary; the appliance is removable and frequently lost or forgotten. Cannot correct significant crowding, skeletal discrepancies, or Class II/III malocclusion on its own. Some labial tipping of incisors may not be desirable in certain cases (proclined pre-treatment).
brackets/tubes used)
tubes
heat-formed shield, attached to the wire ends; shield held 1.5–2 mm labial to anterior teeth
irritation
the lip properly
Adapt molar bands to the model. Bend the wire arms to extend anteriorly from the buccal tubes, curving labially to position the shield correctly. The shield must clear the incisal edges and sit in the labial sulcus — too high creates no force, too low causes tissue irritation. The shield can be prefabricated and attached to the bent wire ends, or custom-acrylic'd directly on the model. Ensure the wire insertion ends are smooth and parallel for easy tube insertion. CFL offers two price points — the difference likely reflects design variant or delivery form. Confirm with the prescribing doctor which molar tube size to match.
most common.
used for upper arch development or Class II with lip trap.
eliminate lip pressure.
pressure relief and lingual holding arch support.
patient-friendly.
Wikipedia](https://en.wikipedia.org/wiki/Lip_bumper)
PubMed](https://pubmed.ncbi.nlm.nih.gov/12539653/)
AJODO](https://www.ajodo.org/article/0889-5406\(91)70070-D/abstract)
business notes.