Advances in Hand instruments

Advances in Hand instruments

TRIPLE FLEX FILE

•          A hybrid instrument.

•          More flutes than reamer but fewer than K-file.

•          Made from triangular stainless steel blank by twisting, not ground.

•          More aggressive & flexible than regular K-style instrument.

UNIFILE

•          Introduced by McSpadden as modification of H- file.

•          Cross section shows double helix or ‘S’ shape.

•          Flutes are less deeper than  H-file, so greater bulk so less likely to fracture.

•          Cutting of dentin is more efficient in withdrawal strokes.

•          S-file is modification of unifile with less fragility.

HELIFILE

•          Modification of H-file.

•           Method of manufacture is similar to H-file.

•          Cross section has three blades.

•          Advantage:

•          more space for removal of dentinal chips & debris.

SAFETY H – FILE

Ø  Modification of H-File done by Buchanan.

Ø  Non cutting tip to prevent ledging into curved canals.

Ø  Smooth edges on one side of file to prevent unnecessary dentin removal in curved canals.

U – FILE

Ø  Developed by Heath (1988).

Ø  Cross-sectional configuration has two 90-degree cutting edges at each of the three points of the blade.

Ø  Advantages:

1.  The flat cutting surfaces act as a planing instrument.
2. Aggressively planes the external convex wall while avoiding the more dangerous internal concave wall.
3. Has a non cutting tip.