Lasers in Medical Science

, Volume 25, Issue 5, pp 629–639 | Cite as

En face optical coherence tomography investigation of apical microleakage after laser-assisted endodontic treatment

  • Carmen Todea
  • Cosmin Balabuc
  • Cosmin Sinescu
  • Laura Filip
  • Cristina Kerezsi
  • Mircea Calniceanu
  • Meda Negrutiu
  • Adrian Bradu
  • Michael Hughes
  • Adrian Gh. Podoleanu
Original Article


The aim of our study was to evaluate the potential of en face optical coherence tomography (OCT) for the detection of apical microleakage after 980 nm and 1,064 nm laser-assisted endodontic treatment. Ninety, human, single-rooted teeth with one straight root canal and closed apices were used. All roots were prepared biomechanically to the working length at an apical size 30 and 0.06 taper. The teeth were divided into three equal groups of 30 samples each, according to the treatment to be applied to the root canal. Group I received 980 nm diode laser (3 W, 0.01 s on time, 0.01 s off time, 5 s per procedure, four procedures); group II received neodymium:yttrium–aluminum–garnet (Nd:YAG) laser (1.5 W, 15 Hz, 5 s per procedure, four procedures). In group III the root canals were approached conventionally only. In all groups the root canal filling was performed with AH Plus endodontic sealer and gutta-percha points. An en face OCT prototype was used for the investigation of apical microleakage. According to one-way analysis of variance (ANOVA) and en face OCT, the number of defects in the laser groups was significantly lower (P < 0.005) than in the control group. No statistical differences were noted between the laser groups (P = 0.049). En face OCT imaging proved that laser-assisted endodontic treatment improved the prognosis of root canal filling and led to a reduction in apical microleakage.


En face optical coherence tomography (OCT) 980 nm Diode laser Neodymium:yttrium–aluminum–garnet (Nd:YAG) laser Apical microleakage Endodontic treatment 



This research was supported by a research grant from the Romanian National Authority for Scientific Research, number CEEX 82/2006. The authors thank Ophthalmic Technologies Inc., Toronto, Canada, for the 3-D imaging program used in Fig. 6, and Politehnica University of Timisoara, Romania, for the optical microscopy investigation.


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Copyright information

© Springer-Verlag London Ltd 2009

Authors and Affiliations

  • Carmen Todea
    • 1
  • Cosmin Balabuc
    • 1
  • Cosmin Sinescu
    • 1
  • Laura Filip
    • 1
  • Cristina Kerezsi
    • 1
  • Mircea Calniceanu
    • 1
  • Meda Negrutiu
    • 1
  • Adrian Bradu
    • 2
  • Michael Hughes
    • 2
  • Adrian Gh. Podoleanu
    • 2
  1. 1.School of DentistryVictor Babes University of Medicine and Pharmacy of TimisoaraTimisoaraRomania
  2. 2.School of Physical SciencesUniversity of KentCanterburyUK

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