Clinically Considerations About Induced Experimental Periodontitis in Rats Treated by Photodynamic Therapy

Periodontitis is a chronic inflammatory condition that affects the soft and hard tissue supporting the tooth, favoring the adhesion of bacteria that can generate dental laxity and bone resorption. This study aimed to test an experimental protocol for inducing periodontitis which allows a close clinical assessment and to evaluate the effectiveness of a photodynamic therapy (PDT) protocol to reverse the associated clinical signs. Fifteen Wistar male rats were used for this study, divided into three equal groups. Tooth scaling, rooting and planning of the first superior left molar were performed in all rats, causing the displacement of the gingiva in order to create an accumulation of plaque. A 5-0 cotton ligature was placed, provoking an inflammatory response removed after ten days. One group received one session of PDT; another group received 3 PDT; the last one represented the control group, with no treatment. Clinical evaluation was represented by assessing the body weight, mobility index and bleeding. A rat grimace scale was used to determine the pain. The results showed clinical aspects of periodontitis and healing tissue proved microscopically. The tested procedure can provide all the key biological factors present in periodontal disease and an option for reversing the clinical aspects.