LETTER TO EDITOR

Year : 2015  |  Volume : 5  |  Issue : 1  |  Page : 66-67

Author's Reply

Vasudev Ballal¹, Jothi Varghese^2
1 Department of Conservative Dentistry and Endodontics, Manipal College of Dental Sciences, Manipal University, Manipal, Karnataka, India
² Department of Periodontology, Manipal College of Dental Sciences, Manipal University, Manipal, Karnataka, India

Correspondence Address:
Vasudev Ballal
Department of Conservative Dentistry and Endodontics, Manipal College of Dental Sciences, Manipal University, Manipal - 576 104, Karnataka
India

Source of Support: None, Conflict of Interest: None

Check

• The samples in your study were sterilized by using ultraviolet radiation and autoclave only once the root canals were prepared. However, my question was whether the samples were disinfected before you started doing the shaping and cleaning of the root canal. Ideally, the teeth samples should be disinfected before we start working on them to prevent the cross infection ^[1]
• In the present study, the antimicrobial efficacy of the herbal irrigants was tested and not their pulp dissolution effect. E. faecalis which was used in this study is a commonly observed microbe in failed root canal treatment. Even though 2% chlorhexidine (CHX) does not dissolve the pulp tissue, it has shown to be very effective against E. faecalis in failed root canal cases. Hence, I feel 2% CHX should have been incorporated as one of the control group in this study
• One of the queries was on the confirmation of biofilm formation on the root canal surface and not the purity of the culture. By doing gram staining, we cannot test for the biofilm formation on the root canal surface. It could have be evaluated by SEM or Confocal laser scanning microscope
• Since this study evaluated for the efficacy of herbal agents on the biofilm of E. faecalis, it would have be prudent to remove the smear layer rather than retaining it. E. faecalis is known to penetrate the dentinal tubules to varying depth when its biofilm is formed. ^[2],[3] Hence, by removing the smear layer and allowing the complete biofilm formation, the efficacy of the test agents could have been evaluated more effectively
• By using paper points, only the planktonic superficial colonies can be removed and cultured for their counts. By taking the dentin shavings of the root canal, the E. faecalis colonies in the biofilm which have penetrated deeper into the root canal dentin could have been evaluated and the results could have been more precise.

References

1.	DeWald JP. The use of extracted teeth for in vitro bonding studies: A review of infection control considerations. Dent Mater 1997;13:74-81.
2.	George S, Kishen A, Song KP. The role of environmental changes on monospecies biofilm formation on root canal wall by Enterococcus faecalis. J Endod 2005;31:867-72.
3.	Al-Nazhan S, Al-Sulaiman A, Al-Rasheed F, Alnajjar F, Al-Abdulwahab B, Al-Badah A. Microorganism penetration in dentinal tubules of instrumented and retreated root canal walls. In vitro SEM study. Restor Dent Endod 2014;39:258-64.