Effect of photodynamic therapy and non-thermal plasma on root canal filling: analysis of adhesion and sealer penetration.

Marilia Menezes,Renata Simão,Heloisa Gusman,Brenda Gomes,Maíra Prado

doi:10.1590/1678-7757-2016-0498

Abstract

Objective The aim of this study was to evaluate the effect of photodynamic therapy (PDT) and non-thermal plasma (NTP) on adhesion and sealer penetration in root canals.Material and Methods Sixty single-rooted premolars were used. The teeth were prepared using a crown-down technique. NaOCl and EDTA were used for irrigation and smear layer removal, respectively. The root canals were divided into three groups: control, PDT, and NTP. After treatments, the roots were filled using gutta-percha and either AH Plus (AHP) or MTA Fillapex (MTAF) sealers. Samples were sectioned at 4, 8, and 12 mm from the apex (1-mm slices)and analyzed by the push-out bond strength test (adhesion) and confocal laser scanning microscopy (sealer penetration). Data were statistically evaluated using Kruskal-Wallis, Dunn’s, and Spearman’s tests.Results Regarding AHP, bond strength was similar in the NTP group and in the control group, but significantly lower in the PDT group. As to MTAF, both therapies showed lower values than the control group. In the confocal analysis of AHP, maximum and mean penetration, and penetrated area were statistically higher in the control group than in the PDT and NTP groups. Penetrated perimeter was similar among groups. Regarding MTAF, all parameters yielded better results in the NTP than in the control group. The PDT and control groups showed similar results except for penetrated area.Conclusion PDT and plasma therapy affected the adhesion and sealer penetration of root canals filled with AH Plus and MTA Fillapex and there is no positive correlation between adhesion and sealer penetration.

Highlights

The basic requirements for root canal treatment are effective chemomechanical preparation and threedimensional obturation of the root canal system1
Plasma therapy results were similar to the control group, whereas photodynamic therapy (PDT) presented significantly low strength when AH Plus was used
This period was chosen because it was the minimum period found in the literature that antimicrobial activity was verified by the same parameters employed in the present study12,19,25

Summary

Introduction

The basic requirements for root canal treatment are effective chemomechanical preparation and threedimensional obturation of the root canal system. Root canal obturation is a very important step for a successful treatment. The use of gutta-percha with various root canal sealers is the most common obturation method. AH Plus sealer (Dentsply Maillefer, Ballaigues, Switzerland) is a resin-based sealer widely used for root canal filling due its acceptable physical properties, low solubility and disintegration, apical sealing ability, good adhesion, antimicrobial action, and good biological properties. Studies have demonstrated AH Plus higher cytotoxic effects compared to MTA-based sealer. MTA Fillapex (Angelus Dental Solutions, Londrina, PR, Brazil) is a calcium silicate-based root canal sealer that contains salicylate resin, diluting resin, natural resin, bismuth oxide, nanoparticulate silica, and MTA. It was developed to utilize the good features of MTA; relatively high levels of biocompatibility, antimicrobial activity, and sealing ability have been reported for this material

Methods

Results

Conclusion