[Root canals dentinal wall structure after photodynamic exposure]

Area of Science:

• Endodontics
• Biomaterials Science
• Dental Microscopy

Background:

• The smear layer in root canals can impede disinfection and healing.
• Effective smear layer removal is crucial for successful endodontic treatment.
• Conventional irrigation methods have limitations in completely removing the smear layer.

Purpose of the Study:

• To evaluate the efficacy of 0.5% photoditazine photodynamic therapy in removing the smear layer from root canal dentinal walls.
• To assess the impact of this therapy on dentinal tubule patency.
• To compare the results with conventional irrigation techniques.

Main Methods:

• Scanning electron microscopy (SEM) was used to examine root canal dentin structure.
• 46 single-root teeth were treated with 0.5% photoditazine and photoactivated with laser or diode light (635-660 nm, 150-200 mW).
• Microphotographs were taken at x2000 magnification in the coronal, middle, and apical thirds of the root canal.

Main Results:

• Photodynamic activation of 0.5% photoditazine effectively removed the smear layer.
• Maximum opening of dentinal tubules to a depth of 2-3 μm was observed.
• Optimal results, characterized by a smear-layer-free surface and numerous open tubules, were achieved with 3 minutes of photoditazine exposure and 2 minutes of laser activation.

Conclusions:

• Photodynamic therapy with 0.5% photoditazine is an effective method for smear layer removal in root canals.
• This technique significantly enhances dentinal tubule opening, potentially improving endodontic treatment outcomes.
• It presents a viable alternative or supplement to conventional root canal irrigation protocols.