Notes on Features and Uses of Reamers Instrument

Notes on Features and Uses of Reamers Instrument

Reamers are K-type instruments which are used to ream the canal. They are symbolized by.

Features of Reamers

(i) Reamers have fewer blades than K-files. Cutting blades are 1/2 to 1 per mm while in file, it is 1 1/2 to 2 per mm.

(ii) Angle of blank is 60° creating a sharp knife like edge to shave the canal. Three 60° angles provide superior cutting efficiency.

(iii) Triangular cross section shows less resistance to bending, are more flexible, and there is less risk to tensional fracture than those made from square blank.

(iv) They are manufactured by twisting triangular blanks and are triangular in cross section

(v) Basic action: Insert into the canal, turn 1/4 to 1/2 clockwise in order that the blades engage into the dentin and then pull so that the dentin chips from the root canal. (Insertion-rotation-retraction)

(vi) Reaming is the only action to produce a round, tapered preparation, when used in straight canals.

(vii) Hand operated instruments are known as type K reamers.

(viii) It is used with pushing rotating motion.

(ix) Engine reamers do not readily follow the course of curved canal and may perforate the root canal. They are likely to break.

(x) Angle of blade to the long axis of K-reamer is about 10-30°. Hence, these instruments are primarily designed to be used in rotary reaming motion.

(xi) Reamers tend to remain self-centered in the canal resulting in less chances of canal transportation.

Uses of Reamers

(i) To enlarge and shape the irregular shapes of root canal into a cavity of rounded cross- section.

(ii) Cleaning and shaping of root canal during Schilder’s method.

(iii) Though reamer has fewer numbers of flutes than file; cutting efficiency is less than that of file.

(iv) More space between flutes provides more room for better removal of debris. They are used to remove the intracanal debris and old gutta-percha fillings from the canal.