Transpalatal Arch and Nance arch
Transpalatal arch and Nance arch or Nance space holding appliance are the types of fixed space maintainers. They are used for maintaining the space between the developing jaws and teeth. In this article, there is a brief discussion on the transpalatal arch and nance arch. Let us examine them.
Transpalatal arch (TPA): (Fixed, non-functional, passive appliance)
- It is used in the maxillary arch. The arch is soldered to both sides, straight,, without a button and without touching the palate.
- The basis of the appliance is that the migration and rotation is caused by rotation around the lingual root. By preventing this, space loss is prevented by the appliance. Also, it is thought that one molar will provide some stability to it's antimere. However, cross arch anchorage can be used if only one of the primary molars is lost and both the permanent molars are erupted.
Nance arch or nance space holding appliance: (Fixed, nonfunctional, passive, maxillary arch appliance)
- Discussing the limitations of the orthodontic treatment, Nance (1947) describes the 'preventive lingual wire'. It consists of bands on the upper molars, with the arch wire extending forward into the vault.
- The acrylic button is present on the slope of the against forward movement (U loop). The wire should extend from the lingual of band to the deepest and most anterior point in the middle of hard palate.
- 'U'bend is given in the wire for the retention of the acrylic 1-2 mm away from the soft tissue.
Disadvantages of the fixed space maintainers
- Maximum failures are encountered with the placement of lingual arches.
- Cement loss and solder failure are found to be high in all appliances.
- Tissue lesions are high with the band and the loop.
- Another important disadvantage is the eruption interference caused by lingual arch in a few cases.