Photothermal therapy (PTT) uses light radiation for the treatment of many medical conditions, including cancer. This approach is an extension of photodynamic therapy, in which a photosensitiser is excited with specific band light. This activation brings the sensitiser to an excited state where it then releases vibrational energy (heat), which kills the targeted cells.
PTT has been developed as an alternative reduced invasiveness option for local therapy and can be used for many different applications from destroying cancers cells to treating mouth infections.
To further enhance PTT efficiency for destroying cancer cells, a photothermal enhancer, ‘porphysomes’, hsd been developed. Porphysomes are intrinsically multifunctional nanovesicles which are self-assembled into liposome-like nanoparticles. Porphysomes provided excellent fluorescence-guidance for following local PTT. The PTT laser ablates the treatment area with the diameter over 10 mm, while the laser alone without porphysome injection only covers a minimal ablated area with less than 2 mm diameter. The porphysome nanoparticles enables improved visualisation of the treatment area and also enhanced local PTT efficiency which demonstrates the potential benefits of porphysome-based image-guided PTT. Unlike photodynamic therapy, photothermal therapy does not require oxygen to interact with the target cells or tissues. Current studies also show that photothermal therapy is able to use longer wavelength light, which is less energetic and therefore less harmful to other cells and tissues.
Antibacterial effect - Regardless of already existing antibiotic resistances, all gram positive/ negative, especially the AA-complex, as well as gram variable and gram undefined types are being destroyed. Due to the germ killing effect no antibiotics are necessary, this avoids problems with already existing resistances or new resistance formations. PTT destroys the bio-film and germs in deep pockets, the patient loses less root substance than during a complete and repeated mechanical cleaning, what leads to a lower hypersensitivity.
PTT works selectively and locally, as it only attaches to inflamed areas. Meanwhile the colouring of the biofilm and the inflamed areas shows where further irradiation is necessary.
PTT is germicidal and enables the elimination of germs. It is widely used by dental practitioners. The PTT Laser kills all gram positive and gram negative bacteria effectively. During activation a sole thermal process takes place. Due to low performance there is neither thermal tissue damage nor photo-thermal erosion through burning or evaporation. No glazing of dentine, as the irradiation takes places with extremely low power. PTT helps the surgeon with scaling & Root Planing.
Diode laser - PTT diode lasers for dental therapy typically have a reserve capacity of 8W, which can be used in different dental therapies. The wavelength of the laser is 810 nm and can be used for applications in surgery, endodontics, bleaching, LLLT and conventional laser-perio therapy.
Edited by John Sandham