Effect of Different Irrigation on Smear Layer Removal after Post Space Preparation

  • Xin-Hua Gu
    Address requests for reprints to Dr Xin-Hua Gu, Department of Stomatology, The First Affiliated Hospital, College of Medicine, Zhejiang University, #79 Qingchun Road, Hangzhou, Zhejiang Province, PR China, 310003
    Department of Stomatology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, PR China
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  • Cai-Yun Mao
    Department of Stomatology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, PR China
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  • Matthias Kern
    Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany
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      The purpose of this study was to evaluate the effect of different irrigating solutions on smear layer removal and dentinal tubule opening on root canal surfaces after post space preparation and to study whether additional ultrasonic irrigation has any effect on smear layer removal. Forty-eight anterior teeth were treated endodontically. After post space preparation, they were assigned to six groups: group 1, EDTA; group 2, EDTA with ultrasonic activation; group 3, sodium hypochlorite (NaOCl); group 4, NaOCl with ultrasonic activation; group 5, sodium chloride (NaCl); and group 6, NaCl with ultrasonic activation. Specimens were examined under a field-emission scanning electron microscope and scored for debris removal and dentinal tubule opening at the coronal, middle, and apical thirds of the root canal. The results showed that EDTA performed significantly better than NaCl and NaOCl in smear layer removal and dentinal tubule opening. Additional ultrasonic irrigation did not improve smear layer removal significantly.

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