Removal of two types of root canal filling material using pulsed Nd:YAG laser irradiation.
OBJECTIVE
The aim of this study was to examine the usefulness of a pulsed Nd:YAG laser in removing two types of endodontic obturation material from the root canal in vitro.


BACKGROUND
Recently, a fine flexible glass fiber made of quartz has been developed to transmit the laser beam more effectively and permit its concentration in a specific area. This has increased the potential usefulness of the Nd:YAG laser in root canal treatment.


METHODS
The time required for removing the root canal obturation material (Gutta-percha cones and, Sealapex or AH26) by means of either Nd:YAG laser irradiation or a conventional method (Gates Glidden drills and K files) was measured. Contact microradiography was used to assess the radiopacity of the root canals before and after the removal of obturation material. The surfaces of the root canal after removal of the obturation materials were also observed by scanning electron microscopy.


RESULTS
Although none of the methods used in this study resulted in complete removal of debris from the root canal wall, the time required for the removal of any of the root canal obturation materials using laser ablation was significantly shorter than that required using the conventional method (p < 0.05). It appeared that some orifices of the dentinal tubules were blocked with melted dentin following laser irradiation.


CONCLUSIONS
Nd:YAG laser irradiation is an effective tool for the removal of root canal obturation materials, and may offer advantages over the conventional method.
Anjo
Tomoo
T
Pulp Biology and Endodontics, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan. t.anjo.endo@tmd.ac.jp
Ebihara
Arata
A
Takeda
Atsushi
A
Takashina
Masaaki
M
Sunakawa
Mitsuhiro
M
Suda
Hideaki
H
D001729:Bismuth / Q000627:therapeutic use; D003786:Dental Pulp Cavity / Q000528:radiation effects; D004338:Drug Combinations; D004708:Endodontics; D004853:Epoxy Resins / Q000627:therapeutic use; D006171:Gutta-Percha / Q000627:therapeutic use; D006801:Humans; D053685:Laser Therapy; D008855:Microscopy, Electron, Scanning; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D018915:Root Canal Preparation / Q000379:methods*; D012834:Silver / Q000627:therapeutic use; D014025:Titanium / Q000627:therapeutic use
D004338:Drug Combinations; D004853:Epoxy Resins; D012387:Root Canal Filling Materials; D012834:Silver; C028044:epoxy resin AH-26; D006171:Gutta-Percha; D014025:Titanium; D001729:Bismuth