Evaluation of presence of voids in two different gutta percha obturation techniques : thermafil, soft core (low heat)‎ (an in vitro study)‎

Abstract EN

Background : Many attempts to achieve fluid tight seal in root canal obturation were tried since that most of failed endodontic treatment were due to insufficient obturation like presence of voids at gutta percha sealer interface or sealer canal wall and gutta percha canal walls interface.

The aim of this study was to evaluate and compare the adaptability of gutta percha root canal fillings achieved with thermafill and soft core( low heat) of two sizes (size of MAF & a one size less than MAF) (35 & 40 iso size) for each type of obturator through counting of voids numbers at gutta percha sealer interface and sealer canal walls and gutta percha canal walls interface Materials and methods : In this study 20 straight distal roots of 8 mm length were sectioned from freshly extracted lower molar and were prepared using protaper system to f4 master apical file then grouped into 4 groups (5 sample for each group).

Group 1 : The root canal in this group were luted using dorifill sealer which was applied by paper point to paint canal wall by thin layer of sealer and then obturated using thermafill obturator (iso size 35) according manufacture instructions.

Group 2 : The root canal in this group were luted using dorifill sealer which was applied by paper point to paint canal wall by thin layer of sealer and then obturated using thermafill obturator (iso size 40) according manufactured instructions.

Group 3 : The root canal in this group were luted using dorifill sealer which was applied by paper point to paint canal wall by thin layer of sealer and then obturated using soft core (low heat) obturators (iso size 35) according manufactured instructions.

Group 4 : The root canal in this group were luted using dorifill sealer which was applied by paper point to paint canal wall by thin layer of sealer and then obturated using soft core (low heat) obturators (iso size 40) according manufactured instructions.

All samples were sectioned at five levels (1mm, 2.5 mm, 4mm, 5.5 mm and 7 mm) from anatomical apex of the root.

One hundred samples were examined using transillumination stereoscope at an original magnification of 20 X and photographed by digital camera at special setting as recommended by manufacturers mounted on microscope.

The number of voids of each section was counted.

Results : The examination resulted in no voids in all sections of the samples in group 2, group 3 and group 4 which were obturated by iso size 40 of thermafill and iso size 35 & 40 of soft core (low heat) respectively.

Two voids were seen in fifth level of sectioning in two samples of group 1 which were obturated by iso size 35 of thermafill obturator.

Conclusion : The presence of voids with the use of the thermo plasticized cone techniques is very rare.