ROOT CANAL FILLING MATERIALS Gutta-percha

Gutta-percha is the most commonly used material for the obturation of the prepared root canal system. Standardized gutta-percha points correspond to the ISO sizing system with a 2% taper. Various other shapes are now available to complement the recently introduced increased taper filing systems (Fig 22). Gutta-percha is the dried resin of the Taban tree, and exists in two forms. Alpha phase is the natural form, but when heated and cooled the beta-phase results. This latter is normally used for root canal filling points.
Gutta-percha points in fact contain only about 20% gutta-percha. The major component
Fig. 21  Spiral fillers may fracture if the size is not verified passively before rotating in the canal.

Spiral root canal fillers

Spiral root canal fillers are seldom used in modern endodontics. Their main use is for the insertion of calcium hydroxide into the root canal. When a spiral filler is required, the blade type is preferred by the author, as this is the least likely to fracture. It is essential to ensure that the size selected fits loosely and passively to the required depth before the instrument is rotated in the root canal (Fig. 21).

Barbed broach

This instrument has sharp rasps pointing towards the handle. They may be used to remove the contents of the root canal before commencing shaping procedures. A vital pulp may be extirpated when carrying out elective endodontic procedures, or when treating a tooth with an irreversible pulpitis, by introducing the barbed broach deep in the canal, twisting it a quarter to a half turn, and withdrawing, as shown in Figure 20.