Photodynamic therapy: a targeted therapy in periodontics

Abstract

The oral cavity is colonized by a large number and highly diversified communities of micro-organisms. Bacterial biofilm present on tooth or root surface is a major cause of gingivitis and periodontitis. Chemical antimicrobial agents are widely used in prophylactic and therapeutic regimens for dental plaque related diseases, which are among the most common human infections. As these agents are difficult to maintain at therapeutic concentrations in the oral cavity and can be rendered ineffective by resistance development in target organisms, there is a need for an alternative antimicrobial approach. A novel approach, photodynamic therapy (PDT), could be a solution to these problems. Lethal photosensitization of many bacteria, both Gram positive and Gram negative was found in many studies. The advantage of this new approach includes rapid bacterial elimination, minimal chance of resistance development and safety of adjacent host tissue and normal microflora. Thus, the available knowledge of photodynamic therapy should encourage a more clinically oriented application of this technique.

Prevention and treatment of biofilms by hybrid- and nanotechnologies

“…[67][68][69] Thus, current research with antimicrobial PDT is focusing on: (1) exploring the photophysical and photochemical properties, (2) exploring chemical properties to develop more effective and clinically compatible nontoxic photosensitizers, (3) bypassing the microbial permeability barrier and investing in novel delivery methodologies, and (4) preclinical and clinical investigations of PDT applications. Some examples of their application are in targeting dental plaques, 70 periodontitis, 71 gingivitis, endodontics, 72 osteomyelitis, 73 infections in cystic fibrosis, 74 infections of permanent indwelling devices (eg, joint prostheses and heart valves and implants), 75 and oral candidiasis. 76 Similar applications in biofilm treatment have also been superior to conventional antibiotics.…”

The Effect of Photodynamic Therapy in the Treatment of Chronic Periodontitis: A Review of Literature

“…7,8 According to Allison et al, PDT involves the use of 3 components: (1) Light, (2) Oxygen free radicals, and (3) Photosensitizer. 9 When the photosensitizer is stimulated by an appropriate light wavelength (wavelengths between 650-900 nm which are within the visible red light and near infrared), it provides free radicals of oxygen that causes tissue damage 10,11 ). The cytotoxic products have a short halflife (about 0.04 µs) and limited radius effect (0.20 µm).…”

Photodynamic Therapy: A View through Light

“…The physical and morphologic characteristics of these surfaces create different ecosystems or niches with distinct bacterial plaque. 13 Wide ranges of persistent human infections are due to microbial biofilms. Microorganisms grow in biofilms stuck to a solid surface where they multiply and form micro colonies embedded in extracellular polymeric matrix, which includes water and nutrient channels.…”