Single and Consecutive Applications of Superhydrophobic aPDT over an in vivo Model of Periodontitis

Periodontitis is an inflammatory and multifactorial disease, and has been described as one of the most common oral diseases worldwide. Wistar rats (n=148) were subjected to the periodontitis model by the use of a cotton ligature during 7 days. The superhydrophobic (SH) device was dopped with verteporfin (V) or Ce-6 (Ce) for single or consecutive (days 0, 1 and 2) applications using 60 and 125 J/cm2. Mechanical debridement associated or not with chlorhexidine were used as positive and negative controls. CFU counting, clinical parameters, histological and inflammatory conditions were evaluated. Three consecutive applications of SH-aPDT decreased P. gingivalis load compared to single and the control groups (p<0.05). Clinical parameters were also improved (p<0.05). Histological and stereometric analyses showed that consecutive applications were more effective than single promoting healing and reducing inflammation. SH-aPDT could be an important tool to inhibit biofilm formation while promoting healing and anti-inflammatory responses.