[Evaluation of adaptation of root canal filled with three obturation techniques in vitro].

Objective: To evaluate the adaptation of root canal filled with three obturation techniques in vitro.

Methods: Fifty-seven cleaned and shaped premolars were divided into three groups, each group including 10 single root canal premolars and 9 double root canal premolars, and filled respectively with following techniques: GuttaFlow paste with single master cone (GF group), cold lateral compaction technique with AH plus sealer (LC group), warm vertical compaction technique with AH plus sealer (VC group). The roots were invested and sectioned at 1 mm interval from crown to apex using a microtome saw under water cooling. Both surfaces of the sections were digitally photographed and measured using a stereomicroscope. The number of sections with voids and the area of voids were measured and analyzed.

Results: The frequency of sections with voids: VC group (21.4%, 76/355) was significantly lower than GF group (47.7%, 173/363) and LC group (52.6%, 190/361), P < 0.0167. There was no significant difference between GF and LC group (P > 0.0167). The percentage of voids area (AV%): GF group was significantly higher than LC and VC group (P = 0.000, P = 0.008). The median of GF group was 2.67, LC group was 1.55, VC group was 1.01. No significant difference between VC and LC group (P = 0.076). The filling quality of isthmus: 86% (85/99) isthmus were well filled in VC, significantly higher than GF group (55%, 43/78) and LC group (58%, 49/84), P < 0.0167. There was no significant difference between GF and LC group (P > 0.0167).

Conclusions: The adaptation of root canal filled with warm vertical compaction technique was superior to cold lateral compaction technique and GuttaFlow technique.