The effect of supplementary methods on root canal cleaning: a study using 3D-printed mandibular molar models

Area of Science:

• Endodontics
• Dental Materials Science
• Biomedical Engineering

Background:

• Effective cleaning of the root canal system is crucial for successful endodontic treatment.
• Residual pulp tissue can harbor bacteria, leading to treatment failure.
• Advanced irrigation and activation techniques aim to improve debris removal.

Purpose of the Study:

• To compare the efficacy of various irrigation and activation techniques in removing simulated pulp tissue from 3D-printed root canal models.
• To evaluate the performance of sonic activation, wireless and wired PUI (passive ultrasonic irrigation), XP-Endo Finisher, and conventional syringe irrigation with sodium hypochlorite (NaOCl).

Main Methods:

• 66 3D resin models of mandibular molars were created from micro-CT scans.
• Simulated pulp tissue was injected into the canals.
• Samples were divided into six groups: saline control, NaOCl positive pressure, sonic activation, wireless PUI, wired PUI, and XP-Endo Finisher.
• Cleaning efficiency was quantified by measuring residual tissue percentage using ImageJ software.

Main Results:

• Saline irrigation was the least effective (53.82% residual tissue in the apical third).
• XP-Endo Finisher, sonic activation, PUI techniques, and NaOCl irrigation significantly outperformed saline.
• XP-Endo Finisher showed the lowest residual tissue in the apical third (5.79%).
• No significant differences were found among activation techniques or between them and positive pressure NaOCl irrigation.
• NaOCl alone effectively dissolved tissue, but activation techniques may be valuable in complex anatomies.

Conclusions:

• While activation techniques showed no consistent statistical advantage over NaOCl irrigation alone, they are beneficial for complex root canal anatomies.
• XP-Endo Finisher and sonic activation are effective in reducing residual tissue, particularly in the apical third.
• Complete root canal debridement, especially in challenging apical areas, remains an area for further research and optimization of irrigation protocols.