ENDODONTICS
RERMOVING SMEAR LAYER DURING ENDODONTIC TREATMENT BY DIFFERENT TECHNIQUES - A INVITRO STUDY . A CLINICAL CASE - ENDODONTIC TREATMENT WITH ER : YAG LASER
Sharonit Sahar-Helft 1a * , Adam Stabholtz 1b
1
Department of Endodontics , School of Dental Medicine , Hebrew University – Hadassah , Jerusalem , Israel a
DMD b
DMD , Professor
Received : October 13 , 2016 Accepted : October 15 , 2016
Available online : October 16 , 2016
Cite this article : Sahar-Helft S , Stabholtz A . Rermoving smear layer during endodontic treatment by different techniques - a invitro study . A clinical case - Endodontic treatment with Er : YAG Laser . Stoma Edu J . 2016 ; 3 ( 2 ): 162-167 .
ABSTRACT
Introduction : Cleaning and shaping the root canal system during endodontic treatment produces a smear layer and hard tissue debris . Removing smear layer through irrigation is a critical adjunct . Objectives : The aim of this study was ( 1 ) to evaluate in vitro the effect of irrigation techniques , irrigation with syringe-needle and laser-activated irrigation with 17 % EDTA in root canals and ( 2 ) to demonstrate the effect of laser activated irrigation in a patient case . Materials and Methods : Sixty extracted teeth were divided into three equal groups ; Group 1 : treated only with ProTaper™ F3 Ni-Ti files . Group 2 : positive-pressure irrigation : 17 % EDTA was used for 60-second irrigation , with a syringe . Group 3 : Er : YAG laser-activated irrigation with 17 % EDTA irrigation was used for 60 second , Laser flat tip was inserted in the upper coronal third of the root canal . Results : Scanning electron microscopy showed that the smear layer is removed most efficiently using laser-activated irrigation with a 17 % EDTA . Conclusion : Smear-layer removal was most effective when the root canals were irrigated using Er : YAG laser at low energy with 17 % EDTA solution . This effect was not observed with the positivepressure techniques . A clinical case demonstrate the effect of using Er : YAG laser activated 17 % EDTA inside root canal . Keywords : endodontic , root canal irrigants , Er-YAG laser , scanning electron microscope , smear layer .
1 . Introduction
Root canal treatment is performed to prevent or treat apical periodontitis . Effective endodontic treatment includes cleaning and shaping complex three-dimensional microstructure in which irregular structures such as isthmuses , apical deltas , and lateral canals may be present . The shaping phase aims to enlarge the canal . However creates a smear layer along the root canal walls 1 . The smear layer consists of a superficial layer on the surface of the root canal wall approximately 1-2 µ thick and a deeper layer packed into the dentinal tubules to a depth of up to 40 µ 2 . It contains inorganic and organic substances , including microorganisms and necrotic debris 3 . In addition to the possibility that the smear layer may be infected , it can also protect the bacteria already present in the dentinal tubules by obstructing intra-canal disinfection agents 4 .
Pashley 5 considered that a smear layer containing bacteria or bacterial products might provide a reservoir of irritants . Thus , complete removal of the smear layer would be consistent with the elimination of irritants from the root canal system 6 . Peters et al . clearly 7 demonstrated that more than 35 % of the surface area of the canals remained unchanged following instrumentation of the root canal using four Ni-Ti preparation techniques . Mechanical instrumentation is always combined with irrigation in order to clean the areas that cannot be reached by instruments , to remove the smear layer , and to promote disinfection . Irrigation of the root canal is traditionally performed using a syringe-needle combination . However , the penetration of the irrigant in the apical third is limited 8-9 . Activation of the irrigation solution is suggested to improve their distribution in the canal system and increase irrigation effectiveness . Recent
* Corresponding author :
Dr . Sharonit Sahar-Helft , Department of Endodontics , School of Dental Medicine , The Hebrew University – Hadassah P . O . Box 12272 , IL-91120 Jerusalem , Israel tel : 972-2-6777828 , fax : 972-2-6778996 , e-mail : helft1 @ bezeqint . net
162 STOMA . EDUJ ( 2016 ) 3 ( 2 )