Periodontitis affects half of the U.S. population over 50, and is the leading cause of tooth loss after 35. It is believed to
be caused by growth of complex bacterial biofilms on the tooth surface below the gumline. Photodynamic therapy, a
technology used commonly in antitumor applications, has more recently been shown to exhibit antimicrobial efficacy.
We have demonstrated eradication of the periopathogens Porphyromonas gingivalis, Fusobacterium nucleatum, and
Aggregatibacter actinomycetemcomitans in vitro using PeriowaveTM; a commercial photodisinfection system. In
addition, several clinical studies have now demonstrated the efficacy of this treatment. A pilot study in the U.S. showed
that 68% of patients treated with PeriowaveTM adjunctively to scaling and root planing (SRP) showed clinical attachment
level increase of >1 mm, as opposed to 30% with SRP alone. In a subsequent larger study, a second PeriowaveTM
treatment 6 weeks after initial treatment led to pocket depth improvements of >1.5 mm in 89% of patients. Finally, in the
most recent multicenter, randomized, examiner-blinded study conducted on 121 subjects in Canada, PeriowaveTM
treatment produced highly significant gains in attachment level (0.88 mm vs. 0.57 mm; p=0.003) and pocket depth (0.87
mm vs. 0.63 mm; p=0.01) as compared to SRP alone. In summary, PeriowaveTM demonstrated strong bactericidal
activity against known periopathogens, and treatment of periodontitis using this system produced significantly better
clinical outcomes than SRP alone. This, along with the absence of any adverse events in patients treated to date
demonstrates that PDT is a safe and effective treatment for adult chronic periodontitis.