A laser‐based endodontic treatment concept

The objective of an endodontic treatment is to preserve the functionality of a natural tooth by either averting the onset of apical periodontitis or, in cases where a lesion already exists, by establishing favorable intra-radicular conditions that promote healing in the peri-radicular region.
Conventional endodontic protocols include cleaning and disinfection of the root space with chemicals supplied with needles and a sealing and obturation of the root main canals. This approach cleans and disinfects the superficial dentin layers of the root very well in the upper and middle part of the root, but not in the apical part or in deep dentin layers, where bacteria may still be present.
With this thesis we aimed to improve cleaning of the root tissue with Diode and 9,300nm lasers as well as to seal the root canal walls tightly to close in any remaining bacteria in the tissue and prevent them from accessing nutrients.
We found that by coating their laser tip black, Diode lasers, which work with wavelengths that are basically not absorbed by water, could be used as heaters and thus cause vapor bubble formation (cavitation) in the liquid and promote liquid penetration into the root canal system and tissues as other tested wavelengths. However, it was not possible to reach the root over full wall thickness with the tested lasers.
With the application of a dual curing resin cement on the root canal walls it was possible to seal and infiltrate the root dentin more and tighter than with a conventional epoxy resin sealer. Future research should focus on new bioinert materials for root dentin infiltration and sealing.