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Haas Palatal Expander


Appliance Purpose / Function:

The Haas Palatal Expander is both tissue and tooth borne providing expansive forces to both the teeth and the palatal vault.

Appliance Components:

  • Bands on the 1st permanent molars expansion screw
  • Swivel key for activation
  • Occlusal rests on 1st bicuspids

Suggested Materials:

  • Wire: Chromium Cobalt or Stainless-Steel wire
  • Solder: Silver Solder (Cadmium Free)


  • Laser welding (no solder)
  • Face mask hooks
  • Habit crib
  • Archwire Tubes
  • Headgear Tubes

Appliance Fabrication Standards:

  • .036 lingual bar that extends to the 1st bicuspid and then turns into the palatal vault to support the palatal acrylic
  • .036 wire turns from the band into the palatal vault to support palatal acrylic
  • Wires should be 1 -1.5mm off the tissue
  • The body of the RPE is as high in the palatal vault as possible without touching the tissue
  • The RPE is aligned with the midline
  • The body of the RPE should be about half way between the anterior teeth and the banded molars