Permeability of the root canal wall and occlusion of dentinal tubules by Ag(NH3)(2)F: A comparison of combined use with pulsed Nd : YAG laser or iontophoresis
K. Yokoyama et al., Permeability of the root canal wall and occlusion of dentinal tubules by Ag(NH3)(2)F: A comparison of combined use with pulsed Nd : YAG laser or iontophoresis, J CLIN LASE, 18(1), 2000, pp. 9-14
Objective: We used SEM-EDX and the Vickers hardness test to compare the pen
etration and hardness of silver resulting from use of either (i) pulsed Nd:
YAG laser or (ii) iontophoresis, after root canal wall shaping using the st
andard method of coating with 38% Ag(NH3)(2)F solution, Summary Background
Data: There have not been any reports of penetration and hardness following
the application of Ag(NH3)(2)F solution together with laser or iontophores
is. Methods: We used 21 extracted human single-rooted teeth randomly divide
d into three groups. Group 1 was coated with Ag(NH3)(2)F, Group 2 was irrad
iated with a Nd:YAG laser after coating with Ag(NH3)(2)F solution, and Grou
p 3 was iontophoresised after coating. Then we observed the permeability of
silver through the root canal wall using SEM-EDX, Results: The results sho
w that iontophoresis after coating with Ag(NH3)(2)F solution (Group 3) resu
lted in the greatest and deepest penetration of silver into the root canal
wall. There was no significant difference between teeth in Groups 1 and 2,
For the hardness test, the 21 teeth were tested using SEM-EDX test, 7 untre
ated teeth were used as a control. The results show that Group 2 (laser tre
atment) teeth were the hardest, Conclusion: We therefore propose that root
canals should be treated using irradiation with an Nd:YAG laser that has be
en coated with Ag(NH3)(2)F solution and that this method provides better re
sults than either iontophoresis after coating, or coating alone.