Filling root canals in three dimensions.

By Schilder H.

Date: 11/1967
Journal: Dent Clin North Am

Summary: 

Purpose: To review the process of endodontic obturation in three dimensions and the techniques used •The final objective of endodontic procedures is total 3-D filling of root canals and all accessory canals.

Review of root canal filling techniques:

-solvent techniques

(GP w/chloroform= Chloropercha paste) result in a significant amount of shrinkage and irritation to apical tissue. Ølateral condensation ( no solvents; used with sealer and accessory points) positive dimensional stability of GP, less likelihood of carrying filling material beyond the root apex but no homogeneous mass formed.

-Silver cone techniques ( always used with a cement; non-resorbable, semi-rigidity permits apical wedging which is presumed to create an apical seal.

-Split cone technique

The silver cone is fitted. Before cementation, the cone is scored deeply with a disk or bur at some distance from its apical end. Then the cone will be severed at the score line  to make space for a post.

Vertical Condensation with Warm Gutta Percha:

•Root canal must be shaped so that a continuously tapering funnel is created.

•The GP cone must be carefully selected and use as little cement as possible.

•The coronal end of cone is seared off with a hot spreader, and warm end is folded into the pulp chamber with a plugger. GP is then heated and forced apically in 3-4 mm increments until only the apical portion of the canal has GP. The remaining portion of the canal is filled with warmed segments of GP, 2-4 mm length.

•Pluggers should be prefitted into the canal.

Summary: 

•Vertical Extent of Root Canal Fillings: 

A root canal system filled in 3D to within .5 or 1 mm of its radiographic apex.

•Overextension and underextension

refer solely to the vertical dimension of the root canal filling, beyond or short of the root apex.

•Underfilling

refers to a tooth whose root canal system has been inadequately obturated in any dimension, leaving large reservoirs for recontamination and infection..

•Overfilling

refers to a root canal system that has been filled in 3D, and where surplus material extrudes beyond the foramen.

Conclusion:

A technique was proposed to fill root canals with a homogeneous, inert, dimensionally stable, physiologically acceptable material which could be manipulated with sufficient plasticity to form a cast of the internal configuration of canal system