TPA (Transpalatal Arch)

The Transpalatal Arch is a 1.0-1.2mm stainless steel wire crossing the palate, soldered to molar bands. It serves multiple functions: anchorage reinforcement, molar rotation, mild expansion, and space maintenance.

• Palatal Wire — 1.0-1.2mm SS wire arched across the palate • Molar Bands — On maxillary first molars • Omega Loop (optional) — In the midline for adjustability • Solder Joints — Silver solder at band connections

The TPA connects the two maxillary first molars, creating a rigid cross-arch unit. This prevents mesial drift of the molars during space closure and reinforces anchorage. The wire can be activated to rotate molars or provide mild expansion (1-2mm).

1. Intraoral scans 2. 3D-print model 3. Fit molar bands 4. Bend 1.0-1.2mm SS wire — 1-2mm clearance from palatal tissue 5. Add omega loop for adjustability (if needed) 6. Solder to bands 7. QC: Wire clearance, solder integrity, passive fit

• Wire: 1.0-1.2mm ASTM F899 SS • Bands: Stainless steel, preformed • Tissue clearance: 1-2mm from palatal mucosa • Omega loop: Midline, 3mm diameter (optional) • QC: Wire position, tissue clearance, band adaptation