Evaluation of apical seal in straight canals after obturation using the Lightspeed sectional method

This study evaluated the sectional gutta-percha obturation technique advocated by Lightspeed Technology, Inc. Single relatively straight-canaled teeth were prepared with rotary instruments and divided into three groups. Groups A and B served as controls and were obturated using laterally condensed gutta-percha and either Roth's 801 or Ketac-Endo sealer. Group C was obturated using the Lightspeed technique that included placement of a 5-mm apical section of gutta-percha, followed by backfill with Ketac-Endo sealer and a single gutta-percha cone. All teeth were suspended in India ink for 14 days then cleared. Four additional teeth, which were obturated as in group C then sectioned, revealed a tightly adapted apical section of gutta-percha with a very thin layer of sealer. However, voids were noted in the middle and coronal areas. There was no significant difference in apical microleakage among the three groups. The sectional method was significantly faster than lateral condensation and seems to offer promise as an effective obturation method.