A Study on Revealing Agents in the Context of Photodynamic Therapy in Dental Medicine - A Literature Review

Abstract

Photodynamic therapy (PDT) also known as Phototherapy or Photo chemotherapy involves the use of a photoactive dye (photosensitive) which is activated by exposure to light of a certain wavelength in the presence of oxygen. Dentists have to deal regularly with oral infections which untreated may cause systemic infections. Oral infections such as caries, periodontal infections and infections of the oral mucosa are available lighting so photodynamic therapy is particularly suitable for oral diseases [1,2]. Antimicrobial chemical treatment is nowadays widely used in the prophylaxis and treatment of inflammation-induced plaque with the risk of resistance development. The use of photodynamic therapy as a therapeutic approach can eliminate this risk, however. Studies in the literature show that both Gram-positive bacteria and Gram-negative bacteria are susceptible to the treatment. Among the advantages of using this method is counted rapid elimination of bacteria, minimal chances of developing bacterial resistance and safety in terms of host tissue and existing normal microflora in the oral cavity [3]. Antimicrobial photodynamic therapy (aPDT) by photochemical reaction uses light at a specific wavelength to activate a nontoxic photosensitizer (PS) in the presence of oxygen to produce cytotoxic products. There are different PSs used in dentistry including methylene blue (MB), toluidine blue O (TBO), indocyanine green (ICG) and curcumin [4].

Strategies toward development of antimicrobial biomaterials for dental healthcare applications

“…(3) molecular oxygen. Chemically PSs are usually macrocyclic compounds with a heterocyclic ring structure (Dascǎlu et al, 2017;Stájer et al, 2020) that requires irradiation of light with adaptive wavelength in presence of oxygen to generate ROS (Stájer et al, 2020).…”

“…So, it either decays back to its original state or the molecule may be converted into its excited triplet (T) state. Now this state may also return to its ground state by phosphorescence or can react further by Types I or II reactions (Balhaddad et al, 2020;Dascǎlu et al, 2017;X. Hu et al, 2018;Soukos & Goodson, 2011;Stájer et al, 2020).…”

“…The 1 O 2 is highly electrophilic and can oxidize the double bonds in biological molecules. Thus it plays an important role in cell damage and death(Balhaddad et al, 2020;Dascǎlu et al, 2017;…”

Photodynamic Therapy with Natural Photosensitizers in the Management of Periodontal Disease Induced in Rats

“…It has a wide absorption range of 300-500 nm (with maximum absorption at 430 nm) and produces strong phototoxic effects, thus being a suitable compound for use as PS. Being a fat-soluble material, this PS has certain restrictions, namely, it requires an oil or other synthetic material to make its water solubility possible, such as for example arnica oil [ 13 ].…”