Transpalatal Arch
A fixed orthodontic appliance that connects the upper first molars across the palate to provide anchorage and control molar rotation and width.
Full Definition
A transpalatal arch (TPA) is a rigid wire appliance soldered or bonded to bands on the upper first molars and passing across the roof of the mouth. It is used to maintain or alter the transverse width of the dental arch, prevent molar mesialisation, and correct molar rotation. It is a passive or active device depending on clinical objectives. Editors will encounter this term in appliance prescriptions, referral letters, and clinical notes, often abbreviated as TPA. It should not be hyphenated.
Usage
Usage note: Do not hyphenate. Often abbreviated TPA after first use; expand on first mention in formal documents.
In Context
- "A transpalatal arch was fitted to prevent anchorage loss during space closure." — Clinical treatment plan
- "The transpalatal arch required adjustment at the patient's third appointment." — Progress note