In vivo performance of the new non-instrumentation technology (NIT) for root canal obturation

The aim of this in vivo study was to compare the radiographic quality of root fillings performed by the NIT-obturation method versus conventional mechanical obturation.

Sixty-six patients needing root canal treatment participated in this study. The treatments were performed by three private practitioners. The root canals were instrumented with K-Flexofiles to a master apical file between sizes 25 and 60, followed by step-back flaring up to size 70. Copious irrigation was used throughout the instrumentation procedure with NaOCl (3%). The teeth were obturated either by lateral condensation, the McSpadden technique (control) or by the new non-instrumentation technology (NIT) with and without using gutta-percha points. In the NIT method, a low pressure was created within the tooth, and AH 26 sealer was sucked into the root canal system. Radiographs of the root-filled teeth were analysed and the length of the root filling, the presence of voids and the area of any other fillings determined.

The root canal fillings of the control group (0.1 +/- 0.1 mm) and those of the NIT/gutta-percha group (0.3 +/- 0.1 mm) were both overextended when taking the apical constriction as a reference point. Root canal fillings of the NIT/gutta-percha group were statistically (P < 0.05) significantly longer than those of the NIT without gutta-percha group. The latter showed slightly underextended root canal fillings (-0.14 +/- 0.1 mm).

The present investigation demonstrated the performance of the NIT-obturation method in vivo. Root canals filled by the reduced-pressure-method using sealer combined with gutta-percha cones exhibited equivalent radiographic quality compared to conventionally filled canals.