Dentinal Tubule Penetration and Dislocation Resistance of a New Bioactive Root Canal Sealer Following Root Canal Medicament Removal Using Sonic Agitation or Laser-Activated Irrigation.

ABSTRACT

OBJECTIVE: To investigate the influence of sonic agitation or laser-activated irrigation techniques on the removal chlorhexidine (CHX) and modified triple antibiotic paste (mTAP) on the sealer penetration depth and dislocation resistance of Guttaflow Bioseal. METHODS: Single-rooted mandibular premolars (n=96) were prepared with rotary nickel titanium instruments and randomly divided into two groups (n=48) based on the intracanal medicaments used Group 1, mTAP; Group 2, CHX gel. After 7 days, the specimens in each group were divided into three subgroups (n=16) based on the supplementary irrigation technique used to remove the medicaments laser activated irrigation (Er, Cr YSGG laser, Waterlase MD, Biolase Technology Inc., San Clemente, CA, USA), sonic agitation (EndoActivator, Dentslpy Sirona Endodontics, PA, USA) and syringe-and-needle irrigation (control) techniques. Canals were filled with single matched-taper gutta-percha cone and a calcium silicate-based sealer (GuttaFlow® Bioseal, Coltène/Whaledent, Langenau, Germany). At the end of three weeks, sealer penetration was investigated using confocal microscopy (n=6), and dislocation resistance was calculated by measuring the push-out bond strength (n=10). Statistical analysis was performed using three-way analysis of variance (ANOVA) and Tukey post-hoc test (P=0.05). RESULTS: Laser activated irrigation resulted in significantly higher depth of sealer penetration compared to sonic agitation and syringe irrigation (P<0.01). The average sealer penetration depths were recorded as 846.6 µm, 786.5 µm and 505 µm in the Er,Cr YSGG laser, EndoActivator and control groups, respectively. The mean bond strength obtained in group 3 (syringe-and-needle irrigation) was significantly less than the other groups (P<0.05). The mean values were 9.08 in the Er,Cr YSGG laser group, 8.44 in the EndoActivator group and 5.08 in the needle group. CONCLUSION: Er,Cr;YSGG laser irrigation to remove the medicaments was advantageous to other irrigation techniques in sealer penetration and dislocation resistance of the sealer.