J Oral Laser Applications 7 (2007), No. 4 (06.12.2007)
Laser Treatment of Hypersensitive Dentin: Comparative ESEM Investigations
Goharkhay, Kawe / Wernisch, Johann / Schoop, Ulrich / Moritz, Andreas
Purpose: To determine by environmental scanning electron microscopic (ESEM) examination whether KTP, diode, and CO2 lasers are able to seal dentinal tubules with and without prior application of different types and concentrations of fluoride.
Materials and Methods: For in vitro environmental scanning electron microscopic (ESEM) examinations, human teeth were irradiated either with a laser alone or with a prior application of a 0.4% stannous fluoride gel, a 1% amino fluoride fluid or a 5% sodium fluoride varnish. Irradiation was performed with a KTP Laser (532 nm) at 0.7 W, a diode laser (810 nm) at 0.8 W, or a CO2 laser (10.6 µm) at 0.3 W for 30 s.
Results: Only the combination of the stannous fluoride gel with CO2 laser irradiation revealed complete closure of the dentinal tubules. Other fluorides combined with the CO2 laser or any combination with the diode laser showed only partly occluded tubules. Fluoridation and KTP laser irradiation attained occlusion of most tubules. No closure of the dentinal tubules was observed in teeth which were treated with fluorides only.
Conclusion: CO2 laser irradiation through a layer of stannous fluoride causes a highly resistant protective layer on sensitized dentin. This layer, induced by physical and chemical bonding mechanisms, provides a superior defense against external stimuli.