NaOCl Irrigation Research Articles

Use of micro-CT to examine effects of heat on coronal obturation.

The aim of this study was to categorize the effects of heat on coronal obturation with gutta-percha and sealer using X-ray micro-computed tomography (micro-CT). Ten single-rooted, extracted human teeth were shaped using ProTaper NEXT files to size X5 (#50/Taper 6%) with 2.5% NaOCl irrigation. A single ProTaper NEXT X5 gutta-percha point was then inserted with epoxy resin (AH Plus) or tricalcium silicate (EndoSequence BC) sealer (n = 5/group), and cut at the cemento-enamel junction. The teeth were scanned using micro-CT (SkyScan1272) to obtain 11 sagittal 2-D images. Three calibrated raters categorized the coronal 0.5 mm of the images into four categories: "swirled sealer and/or gutta-percha without voids" (I), "uniform voids and sealer/gutta-percha" (II), "non-uniform voids and sealer/gutta-percha" (III), and "swirled sealer and/or gutta-percha with voids" (IV). Intra-rater and inter-rater reliability were then calculated. Chi-square tests were conducted to determine the significance of differences in each category between sealers. The intra-class correlation coefficient was 0.55 (same rater/two different times) and Fleiss' kappa (different raters/same image) was 0.34. Categories I, II, III, and IV accounted for 16.4%, 4.2%, 30.3%, and 49.1% for AH Plus, and 6.7%, 4.2%, 27.3%, and 61.8% for EndoSequence BC, respectively. Category IV was most common and Category II the least common. Significant differences were evident between sealers for Category I (P < 0.01).

Comparison of postoperative pain reduction using continuous rotation glide path system with other methods of glide path creation - a systematic review

Objective: Various glide path preparation techniques have been introduced, providing easiness to the practitioners.Recent literature has shown that glide path preparation influences the levels of postoperative pain occurrencein individuals receiving endodontic therapy. This systematic review aims to compare the different glide pathpreparation system in reduction of postoperative pain. Material and Methods: Electronic databases such asPubMed, Scopus, Cochrane Library, LILACS, Google Scholar, and European PMC were searched for publishedarticles until July 2020. The studies included were randomized control trial (RCT) studies published during thistime frame with comparison of continuous glide path system with various other glide path systems in reducingpostoperative pain. The studies were reviewed using Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. The studies were reviewed independently by two reviewers who had assessedthe included studies, extracted data and the quality using the Cochrane risk of bias assessment tool. Results:544 studies were received from the initial search, 11 articles were included in full text appraisal, 4 studieswere obtained for qualitative analysis. Mean VAS Scores showed an increased reduction of postoperative painin continuous glide path treated individuals (1.90-0.20) compared to reciprocating glide path (2.00-0.50) andmanual glide path (3.80-0.85). The consumptions of analgesics were seen to be as follows; Manual Glide Path&gt; Reciprocating Glide Path &gt; Continuous Glide Path. Three out of four studies showed an overall “high” riskof bias and another study showed an overall “unclear” bias. Conclusion: From the achieved results, continuousglide path with 5.25% NaOCl irrigation has shown better reduction of postoperative pain compared to otherglide path systems. Individuals who had undergone manual glide path preparation showed higher incidence ofpostoperative pain compared to other systems. The consumption of analgesics was seen to be higher in manualglide path prepared individuals followed by reciprocating glide path and least being continuous glide path.KEYWORDSAnalgesics; Endodontics; Pain; Root canal preparation; Sodium hypochlorite.

Effects of dyes used in photodynamic therapy on color stability of composite resins.

The aim of this study was to evaluate the effect of dyes used in photodynamic therapy (PDT) on color changes of resin-based composites (RBCs). A total of 120 composite discs were made of microfilled, nanohybrid, and nanoceramic RBCs, and the CIE Lab system was used to assess initial colors with a spectrophotometer. Photosensitizers were used in accordance with the experimental design, as follows: MB (methylene blue), TB (toluidine blue), ICG (indocyanine green), and control (no dye). The samples were irradiated with a 940-nm diode laser. After irradiation, the photosensitizers were removed with distilled water (∆E1) and sodium hypochlorite (∆E2), and final colors were measured. Data were analyzed by the three-way ANOVA and Bonferroni tests (α = 0.05). There was no statistically significant difference between the ICG and control groups; however, the TB and MB groups exhibited the strongest staining. The nanohybrid RBC exhibited the greatest color change, and there were no significant differences between the microhybrid and nanoceramic RBCs. After NaOCl irrigation, ΔE2 values decreased to clinically acceptable values (ΔE2 < 3.3). The intensity of staining of the RBCs differed according to the type of photosensitizer used and the content of the composite resin. The irrigant NaOCl was effective in removing discoloration.

Effects of Chitosan, NaOCl, and EDTA Irrigation Solutions on the Cyclic Fatigue Resistance of Three Nickel–Titanium Endodontic Rotary Files: An In Vitro Study

Introduction The goal of this study was to compare the impact of NaOCl, EDTA, and chitosan on the cyclic fatigue of 2Shape, HyFlex EDM, and RACE EVO. Methods A total of 120 new 2Shape (n = 40), HyFlex EDM (n = 40), and RACE EVO (n = 40) files were subdivided randomly into four groups (n = 10): Group (A) with no immersion, Group (B) with immersion in 5.25% NaOCl for 5 min, Group (C) with immersion in 17% EDTA for 5 min, and Group (D) with immersion in 0.2% chitosan for 5 min. The files were rotated in an artificial canal with a 5 mm radius and a 60° curvature at body temperature until they fractured, and the number of cycles to fracture was measured. ANOVA test and Tukey post-hoc test were used to analyze the data. Results Immersion of the files in NaOCl, EDTA, or chitosan solutions had no significant effect on the number of cycles to fracture (P > 0.05). Conclusion The irrigation solutions did not have any influence on the cyclic fatigue of the tested files.

Effect of two different volumes of sodium hypochlorite on endodontic treatment outcome following single-visit root canal treatment: A split-mouth, double-blind, randomized controlled trial

Aim: This split-mouth (SM), randomized controlled trial was planned to assess the influence of two different volumes (15 ml and 25 ml) of 2.5% of sodium hypochlorite (NaOCl) on the endodontic treatment outcome of teeth with apical periodontitis (AP) by radiographic and clinical evaluation.Materials and Methods: The study protocol was approved by the ethics committee (25/XX/IEC/2017/11). Using block randomization, permanent lower molars with pulp necrosis and chronic AP (periapical index [PAI] of 3 or above) were allotted to two treatment groups as Group I (low volume [LV]) and Group II (high volume (HV)) wherein 3 ml and 5 ml of NaOCl irrigant were used after each Mtwo rotary file, respectively. This NaOCl was activated by a sonic handpiece. With power at 0.80, P < 0.05, and minimum clinically significant mean intergroup difference set at 0.40 units (standard deviation – 0.88 unit) while using the change in PAI score as the primary outcome, a total of 46 subjects per group were recruited to adequately show a difference in success at the 12-month follow-up. Clinical (at 24 h, 3, 6, 9, and 12 months) and radiographic (6 and 12 months) assessment of all cases was done.Results: Due to SM design of the study, there was no difference in the demographics of subjects between both the groups. Pain scores between both groups were statistically nonsignificant preoperatively (P = 0.857) and at 24 h (P = 0.852). However, there was statistically significant difference in preoperative and 24 h pain scores in Group I (P = 0.000) and Group II (0.000). Comparison of intergroup preoperative and 12-month follow-up PAI scores revealed no statistically significant difference (P = 0.667). However, there was statistically significant difference in preoperative and 12-month follow-up PAI scores in Group I (P = 0.000) and Group II (P = 0.000). Intergroup comparison of PAI scores at baseline (P = 0.894) and follow-up (P = 0.526) revealed no significant difference.Conclusion: Based on the results of the present study, it can be suggested that there is no significant advantage of using HV of NaOCl over LV as far as periapical healing and postendodontic pain are concerned.

Impacts of NaOCl and Irritrol irrigation solutions with/without autoclave sterilisation on the cyclic fatigue resistance of different nickel-titanium files.

This research aimed to examine the impact of NaOCl and Irritrol solutions with/without autoclave sterilisation on the cyclic fatigue resistance of ProTaper, WaveOne Gold and Reciproc NiTi files. Seventy files in every group were separated into seven subgroups (n = 10) according to irrigation solutions and sterilisation procedures. The mean and standard deviations of the time to fracture was calculated for each group, and the data statistical analysis was performed (P ≤ 0.05). Significantly higher cyclic fatigue resistance was found in Reciproc files than the other types of files. The differences between the control and other subgroups were found to be statistically insignificant (P > 0.05), except for subgroups 5 and 7 (P ≤ 0.05). Immersing NiTi files in NaOCl or Irritrol with sterilisation for three times considerably reduced the cyclic fatigue resistance of these files. Reciproc files exhibited the highest cyclic fatigue resistance in comparison with ProTaper and WaveOne Gold files.

Comparison of postoperative pain reduction using continuous rotation glide path system with other methods of glide path creation - a systematic review

Background: Various glide path preparation techniques have been introduced, providing easiness to the practitioners. Recent literature has shown that glide path preparation influences the levels of postoperative pain occurrence in individuals receiving endodontic therapy. This systematic review aims to compare the different glide path preparation system in reduction of postoperative pain. Material and Methods: Electronic databases such as PubMed, Scopus, Cochrane Library, LILACS, Google Scholar, and European PMC were searched for published articles until July 2020. The studies included were randomized control trial (RCT) studies published during this time frame with comparison of continuous glide path system with various other glide path systems in reducing postoperative pain. The studies were reviewed using Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. The studies were reviewed independently by two reviewers who had assessed the included studies, extracted data and the quality using the Cochrane risk of bias assessment tool. Results: 544 studies were received from the initial search, 11 articles were included in full text appraisal, 4 studies were obtained for qualitative analysis. Mean VAS Scores showed an increased reduction of postoperative pain in continuous glide path treated individuals (1.90-0.20) compared to reciprocating glide path (2.00-0.50) and manual glide path (3.80-0.85). The consumptions of analgesics were seen to be as follows: Manual Glide Path > Reciprocating Glide Path > Continuous Glide Path. Three out of four studies showed an overall “high” risk of bias and another study showed an overall “unclear” bias. Conclusion: From the achieved results, continuous glide path with 5.25% NaOCl irrigation has shown better reduction of postoperative pain compared to other glide path systems. Individuals who had undergone manual glide path preparation showed higher incidence of postoperative pain compared to other systems. The consumption of analgesics was seen to be higher in manual glide path prepared individuals followed by reciprocating glide path and least being continuous glide path. Keywords Analgesics; Endodontics; Pain; Root canal preparation; Sodium hypochlorite

Comparison of Antimicrobial Efficacy of Diode Laser, Ultrasonic Activated and Conventional Irrigation with 2.5% NaOCl during RCT: An Interventional Study

The aim and objective of the study was to evaluate and compare the antimicrobial efficacy of a diode laser irradiation, ultrasonic activated and conventional irrigation with 2.5% NaOCl on obligatory and facultative anaerobic bacteria in single-rooted canals. Total of 60 permanent maxillary and mandibular single-rooted (single canal) anterior teeth were selected. First microbial sample (S1) was collected after access opening and working length determination, using a sterile paper point. Cleaning and shaping were performed, with each instrument change accompanied by irrigation using 2 mL 2.5% NaOCl. After cleaning and shaping, disinfection protocol using diode laser (group1), ultrasonic activated irrigation with 2.5% NaOCl (group 2) and conventional irrigation with 2.5% NaOCl (group 3) was performed and second microbial sample (S2) was obtained. The colony characters of each type of growth on each media were noted and the organisms were identified using standard biochemical reactions. Gram-positive and gram-negative facultative anaerobe were predominantly isolated from the culture, and the highest reduction of the microbial count was seen in diode laser group with 60.92% followed by the ultrasonic group with 47.22% reduction and least reduction was observed in conventional irrigation with the ultrasonic group with 37.97%. The results were statistically significant with p-value <0.05. Diode laser disinfection showed the highest reduction of microbial count compared to ultrasonic activated and conventional needle irrigation with 2.5% NaOCl group. This study will help us to choose wisely between various irrigating methods and protocols. Diode laser in our study has shown superior disinfection of the root canals compared to others.

Effect of Gallic Acid on the Filling Quality of an Epoxy Resin – Based Root Canal Sealer

Purpose: our study evaluated the effect of Gallic acid irrigation as a final rinse after sodium hypochlorite (NaOCL) irrigation on the filling Quality of an expoxy resin – based sealers. Methods and Materials: Twenty single- rooted human teeth were prepared with the protaper system. The specimens were then divided into the following groups: 5.25%NaOCL irrigation (NaOCL group) and 5.25%NaOCL + 10% gallic acid (gallic acid group). The root canals were filled using single cone technique with protaper F3 cones and Diapro – seal sealer, labeled with rhodamine B dye to allow analysis under a confocal laser scanning microscopy (CLSM). All Samples were sectioned at 3, 5 and 7 mm form the apex and prepared for CLSM analysis. The Penetration segments of the canal were calculated at the apical, middle and coronal thirds. The Mann – Whitney statistical test was used at 5 % significans level. Results: higher percentage of gaps and voids were observed at all root thirds of the NaOCL group when compared to the gallic acid group (P Conclusion: our in vitro results showed that the use of gallic acid as an antioxidant agent after NaOCL irrigation promoted a better interfacial adaptation and penetration of epoxy resin – based root canal sealers.

Effect of root canal irrigant (sodium hypochlorite & saline) delivery at different temperatures and durations on pre-load and cyclic-loading surface-strain of anatomically different premolars

AimTo evaluate the effect of NaOCl (5%) and saline (control) irrigant delivery at different temperatures and durations on pre-load and cyclic-loading tooth-surface-strain (TSS) on anatomically different premolars. MethodologySingle-rooted premolars (n = 36), root-canal-prepared in standard manner, were randomly allocated to six irrigation groups: (A1) NaOCl-21 °C; (A2) NaOCl-60 °C; (A3) saline-21 °C then NaOCl-21 °C; (A4) saline-60 °C then NaOCl-21 °C; (A5) saline-21 °C then NaOCl-60 °C; (A6) saline-60 °C then NaOCl-60 °C. A1-2 received nine 10-min irrigation periods (IP) with NaOCl; A3-6 received nine 10-min IP with saline, followed by 9 IP with NaOCl at different temperature combinations. Premolars (n = 56) with single, fused or double roots prepared by standard protocol, were stratified and randomly allocated to: (B1) saline-21 °C; (B2) saline-80 °C; (B3) NaOCl-21 °C; (B4) NaOCl-80 °C. TSS (μє) was recorded pre-irrigation, post-irrigation and pre-load for each IP and during cyclic loading 2 min after each IP, over 30–274 min, using strain-gauges. Generalised linear mixed models were used for analysis. ResultsBaseline TSS in double-rooted premolars was significantly (p=0.001) lower than in single/fused-rooted-premolars; and affected by mesial-wall-thickness (p=0.005). There was significant increase in loading-TSS (μє) after NaOCl-21 °C irrigation (p=0.01) but decrease after NaOCl-60 °C irrigation (p=0.001). TSS also increased significantly (p = 0.005) after Saline-80 °C irrigation. Pre-load “strain-shift” was noted only upon first saline delivery but every-time with NaOCl. Strain-shift negatively influenced loading-TSS after saline or NaOCl irrigation (A3-6) but was only significant for saline-21 °C. ConclusionsTooth anatomy significantly affected its strain characteristics, exhibiting limits within which strain changes occurred. Intra-canal introduction of saline or NaOCl caused non-random strain shifts without loading. Irrigation with NaOCl-21 °C increased loading tooth strain, as did saline-80 °C or NaOCl-80 °C but NaOCl-60 °C decreased it. A “chain-link” model was proposed to explain the findings and tooth biomechanics.

Bactericidal effect of Er,Cr:YSGG laser irradiation on endodontic biofilm: An ex vivo study

AimThis ex vivo study aimed to evaluate the of Er,Cr:YSGG laser effectiveness in the decontamination of an endodontic biofilm. Materials and methodsSeventy-three single rooted human teeth, freshly were chosen. Each tooth was exposed to four associated species in an endodontic biofilm (Enterococcus faecalis, Streptococcus salivarius, Porphyromonas gingivalis, and Prevotella intermedia) and randomly allocated to one of the seven experimental groups. The group 1 (7 teeth) was used to finalize the reliable biofilm-forming technique. The groups 2 and 3 (15 teeth each group) were irradiated with two different Er;Cr:YSGG laser settings (0,75 W - 40 Hz and 4 W - 40 Hz, respectively). The groups 4 and 5 (15 teeth each group) were irrigated with two different solutions and laser irradiated with the same settings (1,5 W - 15 Hz). The group 6 (6 teeth) was the control group treated only with 4 ml 2,5% NaOCl irrigation during 60 s. ResultsThe observations of group 2 and 3 specimens showed the ripeness of the biofilm with the presence of Enterococcus faecalis and Streptococcus salivarius in chains but in group 3 thermal edge effects produced by the optic fiber in the canal walls were present.The group 4 specimens observation showed an average cleaning of the root canal walls while on the canal walls of group 5 samples the apical third presented several debris and smear layer and in the centre cracks and melting dentin of the radicular wall were observed. ConclusionIn those experimental conditions, this study, demonstrated that Er,Cr:YSGG laser has a canals decontamination ability when associated to NaOCl irrigation.

Postoperative pain after ultrasonically and laser-activated irrigation during root canal treatment: a randomized clinical trial.

To compare the intensity of postoperative pain after primary root canal treatment of asymptomatic teeth when using ultrasonically (UAI) or laser-activated irrigation (LAI). In this superiority randomized clinical trial (ClinicalTrials.gov ID: NCT03981237) with parallel design, fifty-six patients with an asymptomatic tooth in need of primary root canal treatment were enrolled. After chemo-mechanical canal preparation using rotary instruments and NaOCl irrigation, teeth were randomly assigned to two groups and patients were blinded to the final irrigation protocol. In the UAI group (n=28), 60s activation with an Irrisafe tip was done per canal. In the LAI group (n=28), NaOCl was activated with a pulsed Er:YAG (2940nm) laser, equipped with a conical tip, with settings of 50µs, 20mJ at 15Hz for 60s. Patients recorded their pain intensity 6, 24, 48 and 72h after treatment on a 100mm visual analogue scale (VAS), as well as their analgesic consumption. Pain levels and incidence were compared across groups using the Mann-Whitney U-test and chi-square test. Overall, mean postoperative pain intensity was low, with the majority of patients having no or minimal pain 24h postoperatively. At 6h postoperatively, pain intensity and incidence were significantly higher in the UAI group compared to the LAI group (P<0.05). For the other time intervals, no significant differences in postoperative pain incidence or intensity were found. The frequency of analgesic intake did not differ significantly between the two groups. Neither of the activation methods resulted in any adverse effects. Ultrasonically and laser-activated irrigation resulted in low and comparable levels of postoperative pain in asymptomatic patients receiving primary root canal treatment.

Could the Calcium Silicate-Based Sealer Presentation Form Influence Dentinal Sealing? An In Vitro Confocal Laser Study on Tubular Penetration.

Dentinal tubule penetration influences root canal treatment sealing. The aim of this study was to compare dentinal penetration of two clinical presentations of silicate-based sealers using confocal laser. Sixty single-rooted human teeth from 50–70 year-old patients extracted for orthodontic/periodontal reasons were used. Canals were prepared using Mtwo system up to 35/0.04, with 5.25% NaOCl irrigation and final irrigation using 17% EDTA. Teeth were randomly assigned into study groups (ni = 20): EndoSequence BC sealer (ES, group 1), BioRoot RCS (BR, group 2); and a control group (nc = 20) with AH Plus (AHP). Root canals were obturated with 35/0.04 gutta-percha (single-cone technique). The samples were obtained from apical, middle, and coronal thirds. Dentinal tubule penetration depth and percentage of penetration around the canal perimeter were measured. The statistical analysis was performed using Mann Whitney U test and Wilcoxon t-test (95% confidence interval). ES exhibited a significantly higher penetration than AHP in apical and middle thirds (p < 0.05), and in middle and coronal thirds relative to BR (p < 0.05). The percentage of penetration around the canal perimeter was significantly higher for ES compared to BR in all thirds, but only in the apical third for AHP (p < 0.05). The pre-mixed silicate-based sealer exhibited better penetration than the powder/liquid one.

Effect of Sodium Thiosulfate on Interfacial Adaptation and Penetration of an Epoxy Resin-Based Root Canal Sealer.

Our study evaluated the impact of sodium thiosulfate (ST) irrigation, subsequent to sodium hypochlorite (NaOCl) and just before root canal filling, on the filling quality (interfacial adaptation and penetration segment) of an epoxy resin-based root canal sealer. Twenty single-rooted human teeth were prepared with the ProTaper system. The specimens were then divided into the following groups: 5.25% NaOCl irrigation (NaOCl group) and 5.25% NaOCl irrigation+0.5% sodium thiosulfate (NaOCl+ST group). The root canals were filled using single-cone technique with ProTaper F3 cones and AH-Plus sealer, labeled with rhodamine B dye to allow analysis under a confocal laser scanning microscopy (CLSM). All samples were sectioned at 2, 4, and 6 mm from the apex and prepared for CLSM analysis. The percentage of voids, gaps and dentinal sealer penetration segment of the canal were calculated at the apical, middle and coronal thirds. The non-parametric Mann-Whitney statistical test was used at 5% significance level. Higher percentage of gaps and voids were observed at all root thirds of the NaOCl group when compared to the NaOCl+ST group (P<0.05). There was a significant increase in the penetration segment of NaOCl+ST group at the coronal and middle root third when compared to the NaOCl group (P<0.05). Our in vitro results showed that the use of ST as an antioxidant agent after NaOCl irrigation promoted a better interfacial adaptation and penetration of epoxy resin-based root canal fillings.

Anatomic Variation in Palatal Root of Maxillary Second Molar: Endodontic Management

The aim of the present clinical case report is to describe the singular root canal anatomy and endodontic management of a maxillary second molar with two palatal roots and two separate canal orifices. A 60 years-old female Hispanic/Latino patient attended the Endodontic Department at University of Buenos Aires School of Dentistry with acute pain in her maxillary left second molar. Clinical radiographs examination revealed unusual root morphology. Cleaning and shaping were completed with 5.25% NaOCl irrigation, 15% EDTA solution and hand/rotary instruments. Filling was performed with gutta-percha points and resin-based sealer. After one year follow-up periapical radiographs and CBCT images showed healing in the area and patient was asymptomatic.

Micro-computed tomographic evaluation of single-cone obturation with three sealers.

ObjectivesThis study used micro-computed tomography (µCT) to compare voids and interfaces in single-cone obturation among AH Plus, EndoSequence BC, and prototype surface pre-reacted glass ionomer (S-PRG) sealers and to determine the percentage of sealer contact at the dentin and gutta-percha (GP) interfaces.Materials and MethodsFifteen single-rooted human teeth were shaped using ProTaper NEXT size X5 rotary files using 2.5% NaOCl irrigation. Roots were obturated with a single-cone ProTaper NEXT GP point X5 with AH Plus, EndoSequence BC, or prototype S-PRG sealer (n = 5/group).ResultsThe volumes of GP, sealer, and voids were measured in the region of 0–2, 2–4, 4–6, and 6–8 mm from the apex, using image analysis of sagittal µCT scans. GP volume percentages were: AH Plus (75.5%), EndoSequence BC (87.3%), and prototype S-PRG (94.4%). Sealer volume percentages were less: AH Plus (14.3%), EndoSequence BC (6.8%), and prototype S-PRG (4.6%). Void percentages were AH Plus (10.1%), EndoSequence BC (5.9%), and prototype S-PRG (1.0%). Dentin-sealer contact ratios of AH Plus, EndoSequence BC, and prototype S-PRG groups were 82.4% ± 6.8%, 71.6% ± 25.3%, and 70.2% ± 9.4%, respectively. GP-sealer contact ratios of AH Plus, EndoSequence BC, and prototype S-PRG groups were 65.6% ± 29.1%, 80.7% ± 25.8%, and 87.0% ± 8.6%, respectively.ConclusionsPrototype S-PRG sealer created a low-void obturation, similar to EndoSequence BC sealer with similar dentin-sealer contact (> 70%) and GP-sealer contact (> 80%). Prototype S-PRG sealer presented comparable filling quality to EndoSequence BC sealer.

Efficacy of Laser Photoacoustic Streaming in Paediatric Root Canal Disinfection - An Ex-Vivo Study.

Background:Various techniques have been employed to enhance the root canal disinfection rate using sodium hypochlorite (NaOCl) as an irrigant. Photon initiated photo-acoustic streaming using lasers is a newer method of endodontic disinfection.Aim:The aim of this study is to evaluate and compare the efficacy of photo-initiated photoacoustic streaming and conventional irrigation technique using 2.5% NaOCl for root canal disinfection in primary teeth.Setting and Design:Laboratory setting and ex-vivo design.Materials and Methods:Twenty extracted primary teeth were selected in which Enterococcus faecalis incubation was done in the root canals and bacterial counts were obtained before the intervention. The teeth were randomly allocated into two groups. Group I samples were irrigated with conventional syringe method using 2.5% NaOCl and Group II samples were irrigated using photon-initiated photo-acoustic streaming method with erbium-doped yttrium aluminum garnet laser (wavelength - 2940 nm). Postintervention samples were obtained, and bacterial colony count was done. Wilcoxon Signed- Ranks Test and Mann–Whitney test were applied to test the intragroup and intergroup differences in the bacterial counts. Results:Postintervention results showed no bacterial growth in the canals irrigated using Laser (P = 0.004) whereas, fewer bacterial colonies were observed in NaOCl group (P = 0.005). There was statistically significantly higher reduction in E. faecalis counts in Laser Activated irrigation (LAI) group compared to NaOCl group (P < 0.05).Conclusion:Total elimination of E. faecalis counts was obtained by the use of laser activated NaOCl irrigation in the infected root canals, hence, it can be considered as an effective method for pediatric endodontic disinfection.

Comparison of cyclic fatigue resistance of heat-treated nickel-titanium reciprocating instruments at the intracanal temperature

Background/Aim: The aim of the present study was to compare the cyclic fatigue resistance of NiTi files running with reciprocal motion and having different characteristics (RPC Blue, WOG, EndoArt Wise Reciproc Gold, EndoArt Wise Reciproc Blue) at the intracanal temperature (35°C) by using NaOCl irrigation solution. Material and Methods: Totally 60 WaveOne GOLD (Dentsply-Sirona, Ballaigues, Switzerland), Reciproc Blue (VDW, Munich, Germany), EndoArt Wise Reciproc Gold, and EndoArt Wise Blue (Inci Dental Productions Co, Istanbul, Turkey) (n= 15) files were used. Each of the rotary files were tested at the intracanal temperature (35°C) using a dynamic model in a stainless-steel artificial canal with an inner diameter of 1.5 mm, 60° angle of curvature, and 2mm radius of curvature until fracture occurred. The device automatically stopped at the moment of fracture and the number of cycles to the fracture was calculated as per second. The lengths of fractured parts were measured using a digital microcaliper. The One-Way Analysis of Variance (ANOVA) and Tukey's posthoc tests were used for intergroup comparisons. Results: In 2 mm Radius of curvature, the EndoArt Wise Reciproc Blue group had a significantly higher time to fracture followed by the EndoArt Wise Reciproc Gold, Resiproc Blue, WaveOne Gold. No significant difference was found between EndoArt Wise Reciproc Gold and Resiproc Blue groups (P&gt;0.05). Among the groups, there was no statistically significant difference in the lengths of fractured parts of the instruments (P&gt; 0.05). Conclusions: EndoArt Wise Reciproc Blue files exhibited significantly higher cyclic fatigue resistance compared with other files tested in a 2-mm radius of curvature and a 600 angle in an artificial canal at the intracanal temperature.

Comparing the Efficacy of Toluidine Blue, Methylene Blue and Curcumin in Photodynamic Therapy Against Enterococcus faecalis.

Introduction: Antimicrobial photodynamic therapy (aPDT) as a supplement to the conventional root canal preparation has shown promising results. Previous studies have adopted various combinations of light sources and photosensitizers, which makes it difficult to compare the disinfection efficacy of different PDT protocols. The aim of the present study was to compare the efficacy of three photosensitizers (toluidine blue, methylene blue, and curcumin) in PDT using LED against Enterococcus faecalis in root canal disinfection. Methods: Root canals of 54 single-rooted extracted teeth were prepared using the ProTaper Gold rotary system and were incubated with E. faecalis for three weeks. They were then randomly divided into five experimental groups and a control group: (1) Irrigation with 2.5% NaOCl for 30 seconds, (2) NaOCl irrigation followed by TB-PDT, (3) NaOCl irrigation followed by MB-PDT, (4) NaOCL irrigation followed by curcumin-PDT, (5) Curcumin solvent (1% ethanol+1% BSA), (6) Control (irrigation with normal saline). Sampling was done by collecting dentin shavings from the root canals, and colony-forming units were determined for each treatment group. The data were analyzed by Kruskal-Wallis and Mann-Whitney U tests. The significance level was set at P<0.05. Results: In all treatment groups, the mean values of colony forming unit (CFU) decreased by 99% compared to the control group. The lowest mean values of CFU were observed in groups 2 and 4, followed groups 3, 1, and 5 respectively. The mean CFU count in group 2 was significantly lower than that of group 1 (P value=0.011), while there were no significant differences among groups 1, 3, and 4 (P value >0.05). Conclusion: The adjunction of toluidine blue-mediated PDT by means of a light-emitting diode to NaOCl irrigation increased its antibacterial efficacy against E. faecalis and could be an effective complementary method in root canal disinfection.

Efficacy of antimicrobial photodynamic therapy administered using methylene blue, toluidine blue and tetra 2-mercaptopyridine substituted zinc phthalocyanine in root canals contaminated with Enterococcusaecalis.

Traditional chemomechanical treatment procedures are an indispensable part of endodontic treatment, however, additional treatment approaches such as antimicrobial photodynamic therapy (aPDT) may also be recommended for the elimination of residual microorganisms. In this study, the disinfection efficiency of aPDT performed using methylene blue (MB), toluidine blue (TB), and tetra 2-mercaptopyridine substituted zinc phthalocyanine (TM-ZnPc) was compared in the roots contaminated with Enterococcus faecalis (E. faecalis). Forty-nine teeth with a single root and canal were included in this study. The roots were sterilized, and inoculated with E. faecalis. The roots were kept in an incubator for 30 days to form the biofilm. Forty-five teeth were prepared up to the F3 file of the ProTaperNext system under 2.5 % NaOCL irrigation. The samples were divided into three groups according to the type of used photosensitizer (PS) (n = 15); MB (313 μM), TB (327 μM), and TM-ZnPc (6μM). All PSs were irradiation with a light-emitting diode (LED) lamp (630 nm, 2-4 mW/cm²) for the 60 s. Two microbiological samples of the intracanal content were taken (one before and one immediately after additional aPDT in all groups) using sterile paper points. The colony-forming units per milliliter (CFU/mL) were calculated after 24 h of incubation at 37 °C. After all aPDT protocols, intracanal bacterial load decreased significantly compared to the amount after chemomechanical preparation (P < 0.05). No significant difference in the reduction in intracanal bacterial load was found between the PSs (P < 0.05). In the current study, the aPDT protocol performed with TM-ZnPc provided similar antimicrobial efficacy, although it was used at a lower concentration compared to MB and TB. Therefore, the use of TM-ZnPc in intra-canal disinfection in endodontics seems promising.