With an increase in the number of implants being placed, clinicians are seeing more instances of failure due to peri-implantitis. This inflammatory process revolves around Gram-negative bacteria, such as Porphyromonas gingivalis, as well as the interaction between the bacterial endotoxin, lipopolysaccharide (LPS), and the implant surface. LPS adheres tenaciously to the implant surface and acts as a chronic inflammatory stimulus. Bacterial death releases additional LPS, which increases the inflammatory reaction around the implant. The best treatment protocols should address both bacterial elimination and LPS removal. The Nd:YAG laser has been shown to be both safe and effective at high frequency and low energy at ablating bacteria. The original article authored by Gianelli, et al appeared in the June 2009 Journal of Periodontology and investigated laser irradiation with an Nd:YAG laser to determine if it could lessen the LPS-mediated inflammatory response. Murine macrophages and human umbilical vein endothelial cells were placed on various combinations of culture media, titanium disks, and titanium discs coated with P gingivalis. Controls were tested for nitric oxide (NO) formation and other various criteria as indicators of inflammatory response and endothelial cell adherence. Some of the disks were pretreated with exposure to 1,064 nm Nd:YAG irradiation at 20 mJ and 70 Hz. The study found that the criteria used to measure macrophage activation such as NO production were significantly reduced in the disks treated with laser irradiation versus those that were not. The authors conclude that Nd:YAG laser irradiation is effective both as a bacterial decontamination process and in inhibiting LPS-mediated inflammation without having a deleterious effect on the titanium implant surface.
(Source: What’s New II?, Oakstone Publishing, July 2009.)
