In vitro Comparison of Apically Extruded Debris during Root Canal Retreatment with Rotary and Reciprocating Systems

The extrusion of apical detritus during the retracting procedure is very important, as, besides eliminating materials of radicular obturation, aggressive agents and products such as the remains of dentin taken out, and microorganisms are generally located in tissue around the roots, producing undesired effects, such as inflammation, acute pain, post-operatory pain and delays in the periapical treatment.

To determine the amount of apically extruded detritus using rotary and reciprocating retreatment systems.

An experimental comparative study as conducted in which 40 single-rooted human first premolars were analyzed. The instruments used were ProTaper Universal files up to F3 and sodium hypochlorite, and the sealing was made through the hybrid technique Tager. They were then kept at 37ºC and 100% of humidity for 15 days so that the sealing material would seal. For the retracting procedure, experimental tubes previously weighted were used. The sample was divided randomly into two groups of 20 pieces. Group A: ProTaper R, and group B: Reciproc. Then, the irrigating material (distilled water) was evaporated from the tubes for 12 hours in a stove at 105ºC, and the experimental tubes were weighted in an analytical precision weighing scale 10^-5g. The data was analyzed through the T Student with a significance level of 5%.

Results indicated that groups A and B, retreatment with rotational ProTaper R and reciprocating retreatment system (Reciproc) showed a similar difference of initial and final weights, indicating similar apical extrusion of detritus.

Both systems extruded a similar amount of detritus during the retreatment procedures.