Evaluation of Dentin Adaptability of Fluoride Varnish as a Root Canal Sealer Using Scanning Electron Microscopy

  • Salma Omidi Department of Endodontics, Dental School, Mazandaran University of Medical Sciences, Sari, Iran
  • Alireza Ahadian Private Practice, Mashhad, Iran
  • Golnaz Hadidi Private Practice, Ramsar, Iran
  • Seyed Jaber Mousavi Department of Community Medicine, Ramsar Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
  • Maryam Forghani Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
Keywords: AH Plus, Root Canal Filling Materials, Root Canal Sealants, Fluoride Varnish, Scanning Electron Microscopy


Objectives: This study aimed to assess the dentin adaptability of a certain type of fluoride varnish, as a novel root canal sealer, in comparison with AH-Plus sealer.

Materials and Methods: Twenty-four extracted single-rooted, single-canal human permanent teeth with straight and fully formed roots and no internal calcification, resorption or cracks, were selected and decoronated such that the remaining root length was 14 mm in all teeth. Root canals were prepared using the Mtwo rotary file system according to the manufacturer's instructions and filled with gutta-percha and either AH-Plus (n=12) or fluoride varnish (n=12) via the lateral compaction technique. Each root was then sectioned at 4 and 8 mm distances from the apex for evaluation under a scanning electron microscope (SEM). The gap size between the sealer and dentin was measured. Statistical analysis was performed using the Kolmogorov-Smirnov test and t-test with the significance level set at 0.05.

Results: The mean gap size was 14.407±1.402 µm and 8.342±0.694 µm in the roots obturated with AH-Plus and fluoride varnish sealers, respectively. The t-test revealed a statistically significant difference (P<0.001) in this regard between the two groups.

Conclusion: Fluoride varnish, as a root canal sealer, has a superior adaptation to dentinal canal walls compared to the AH-Plus sealer.


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How to Cite
Omidi S, Ahadian A, Hadidi G, Mousavi SJ, Forghani M. Evaluation of Dentin Adaptability of Fluoride Varnish as a Root Canal Sealer Using Scanning Electron Microscopy. Front Dent. 16(5):335-341.
Original Article