Evaluation of Parameters of Tissue Dosimetry in Photodynamic Therapy for the Treatment of Periodontal Disease - clinical study

Abstract

Periodontal disease is an inflammatory disease of the support tissue of the teeth induced by microorganisms and influenced by immune-inflammatory response of the host. Mechanical periodontal treatment based on scaling and root planning can often not completely remove the periodontal pathogens and thus require the adjuvant use of antibiotics. In order to reduce the use of antibiotics, antimicrobial photodynamic therapy (PDT) may be used as adjunct to conventional periodontal treatment. However, studies show many discrepancies between the parameters adopted for the PDT, making it difficult to compare results and measure its efficacy. The objective of this research is to investigate the dosimetric parameters used in PDT for the treatment of periodontal disease. This clinical trial will include 20 patients with chronic periodontitis according to the eligibility criteria. Patients in periodontal treatment will be recruited from Dental Clinic of Nove de Julho University, where the research will be developed. Three incisors will be selected form each patient for experimental procedures. Initially, the pattern of light scattering will be recorded by image with intraoral photographs. Then, photodynamic therapy will be performed with three irradiation periods of 1, 3 and 5 min. It will be used laser with wavelength of 660 nm and 100 mW of power. Methylene Blue will be used as photosensitizer at a concentration of 100 µM. The concentration of methylene blue in periodontal pockets will be assessed by spectrophotometer before irradiation. Furthermore, microbiological evaluation will be performed from samples of subgingival periodontal pockets of experimental sites before and immediately after the irradiation procedures. The data will be analyzed statistically. (AU)