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SM120 Lingual Arch with Adjustment Loops

Appliance Purpose / Function:
The lingual arch appliance is a fixed appliance designed primarily to hold “E” space resulting from prematurely exfoliating second primary molars. In addition to holding space left as a result of premature tooth loss, the lingual arch can be used as an anchorage device in extraction cases, to maintain transverse arch width, and to prevent molar tipping resulting from some arch mechanics. With the addition of adjustment loops, the appliance may be used to assist in rounding out the anterior segment of the arch, or the loops may allow adjustment to maintain contact with the teeth as they are proclined as the result of various arch wire treatments.

Appliance Components:

  • Bands on the 1st permanent molars
  • .036 wire is bent from molar to molar

Suggested Materials:

  • Wire: Chromium Cobalt wire
  • Solder: Silver Solder (Cadmium Free)


  • Laser welded (removes the solder)
  • Soldered Occlusal rests

Appliance Fabrication Standards:

  • The base arch slightly off the tissue
  • The base arch touches all of the posterior teeth
  • The base arch, when bent in ideal arch form touches some, or all, of the anterior teeth
  • The adjustment loops are placed between the cuspids and the molar bands, 1-1.5 mm from the tissue
  • The wire placed at the top 1/3 of the band and laying against the band for 4 to 5mm

All information is from