The influence of instrument application frequency on the apical extrusion of debris using rotary ProTaper, hand ProTaper and hybrid technique : an in vitro study

الملخص EN

Background : Various kinds of hand-held or rotary instruments and techniques are used for mechanical preparation of the canal during root canal treatments.

These instruments and techniques may push debris out of the canals which may induce inflammation within the periapical area; therefore, instrumentation technique that causes less extrusion of debris is more desirable.

The aim of this study was to compare the effect of instrument application frequency on the amount of apically extruded debris. Materials and Methods : One hundred and twenty extracted human teeth were used in this study; all teeth were shortened to a length of 15 mm.

Each experimented root was mounted on a centrifuge tube that forced through a precut hole in a rubber stopper of a glass vial.

The roots were divided randomly into 3 groups, each group contained 40 roots.

Group R : prepared by rotary ProTaper, Group H: prepared by hand ProTaper, Group S : prepared by Hybrid technique.

Each group was further subdivided in to five subgroups (A, B, C, D, and E).

Debris extruded from apical foramen was collected in a centrifuge tube containing 0.5 milliliter of distilled water.

Each empty centrifuge tube was weighed before preparation by 0.0001g.

sensitive weighing machine.

Then at the end of canal preparation, these centrifuge tubes were completely dried using an incubator at 68 C° for two days and weighed again.

The difference between the weights of tubes in two stages represented the weight of debris extruded from apical foramen during instrumentation. Results : No significant difference recorded for the mean weight of apically extruded debris regarding the instrument application frequency within the same instrumentation technique; but there was a high significant difference for the subgroups (A, B, C, and D) and a significant difference for subgroup E, regarding the effect of instrumentation techniques on amount of apical extrusion of debris among tested groups. Conclusion : The hand ProTaper extruded smaller amounts of apical debris than the rotary ProTaper and larger amounts than Hybrid technique.