The effectiveness of rotary and hand instrumentation on the removal of gutta-percha during endodontic re-treatment using two types of solvents : a comparative study

الملخص EN

Background : Endodontic treatments are not free of failures and re-treatment of failed cases is a common procedure reflecting an increasing demand to save the teeth.

This study aimed to assess the efficacy of Hedstrom files, ProTaper rotary files and ProTaper rotary re-treatment files for removal of gutta-percha and sealer from root canals with the aid of xylol (dimethyl-benzene) and Carvene GP solvents (d-Limonene) and measuring the time of removal with quantifying the amount of solvent consumed by each removal technique.

Materials and methods : Sixty extracted single rooted teeth instrumented with ProTaper rotary files and obturated with lateral compaction of ProTaper gutta-percha points and TubliSeal sealer.

After incubation period of one week, the samples randomly divided into two main groups (30 specimens each) according to the solvent employed (group A with xylol and group B with Carvene) then each group subdivided into three groups (10 samples each) according to the removal technique: group A1: Hedstrom files and xylol, group A2: ProTaper rotary files and xylol, group A3: ProTaper rotary re-treatment files and xylol, group B1: Hedstrom files and Carvene, group B2: ProTaper rotary files and Carvene, group B3: ProTaper rotary re-treatment files and Carvene.

Radiographs taken and the images digitized.

The percentage of filling material area removed was calculated by MATLAB software.

The working time was measured with digital stop watch and the amount of solvent was measured by insulin syringe.

Data were analyzed statistically by ANOVA and Student t-test at 5 % significant level.

Results : The results showed that gutta-percha removal with rotary files better than with hand files and the group that showed better results is group B2.

The time of removal with aid of Carvene solvent was significantly faster than with xylol solvent in all the groups.

The amount of Carvene solvent consumed during removal procedures was significantly less than the amount of xylol solvent.

Conclusion : Carvene solvent could be considered as potential xylol substitute.

ProTaper universal system for instrumentation and re-treatment is effective and faster in removing gutta-percha.