Evaluation of Root Canal Debridement of Human Molars Using the GentleWave System

Published:August 11, 2015DOI:


      • Recently, a novel device, the GentleWave System was shown to have a higher tissue dissolution rate in a simulated tooth model than traditional and contemporary endodontic methods.
      • We evaluated the tissue debris removed from the root canal system after it was cleaned using the GentleWave System and compared it with those cleaned using conventional instrumentation with needle irrigation.
      • The GentleWave System cleaned approximately 97.2% of tissue debris in the apical and middle region of mesial roots of mandibular molars.
      • An increase in the cleaning quality of complex anatomic regions such as the isthmus regions was observed when teeth were cleaned with the GentleWave System as compared to traditional methods.



      Studies using conventional endodontic protocols show insufficient cleaning of root canal systems, often resulting in persistent infection and treatment failure. The GentleWave System (GWS; Sonendo, Inc, Laguna Hills, CA) has been shown to result in a higher tissue dissolution rate in a study using bovine muscle. The purpose of this study was to compare the debridement efficacy of the GWS with a traditional method for cleaning root canals.


      Forty-five freshly extracted molars were randomly separated into 3 treatment groups (n = 15/group): group 1, no treatment; group 2, conventional rotary instrumentation and needle irrigation; and group 3, minimal instrumentation and the GWS treatment. Roots were prepared per standard histologic tissue processing after hematoxylin-eosin staining; sections were microscopically examined, and the percentage of soft tissue and debris remaining within the canals was morphometrically calculated. Images of the apical and middle regions of the roots were blindly analyzed.


      Significant differences (Welch's t test) were found between groups 2 and 3 in both apical (P = .0015) and middle (P = .0179) regions of the mesial roots of mandibular molars and mesiobuccal roots of maxillary molars. Groups 2 and 3 resulted in cleaning 67.8% and 97.2% of the mesiobuccal and mesiolingual root canals of mandibular molars and the mesiobuccal canals of maxillary molars, respectively, whereas the results were similar among groups 2 and 3 in the apical and middle regions of distal roots. Groups 2 and 3 revealed significantly less debris than group 1 (P < .005).


      The GWS showed a significantly greater cleaning capacity and reduction in residual debris within the mesiobuccal and mesiolingual canals of mandibular molars and the mesiobuccal canals of maxillary molars than those cleaned conventionally.

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