Accuracy of the integrated electronic apex locator in locating simulated perforation under various irrigating solutions in an in vitro study

Aim: This study's objective was to assess the accuracy of the integrated apex locator in identifying artificial root canal perforations in the presence of saline, chlorhexidine, sodium hypochlorite, QMix, and MTAD. Methods: The root canals of 60 single-rooted extracted human teeth were perforated artificially at a point 10 mm away from the root apex. After measuring the actual lengths up to the perforation point, the teeth were then put within an alginate mould for measurements using an integrated apex locator. Using a #20 K-file in the presence of NaCl, CHX, MTAD, NaOCl, and QMix, an electronic apex locator was used to measure the perforations electronically in accordance with the manufacturer's instructions. Between the measurements, each canal was dried with paper points after being irrigated with distilled water. The accuracy of all the readings was calculated at ± 0.5 mm. Statistical analyses were performed using the Z-test. Results: In comparison to the MTAD, NaOCl, and Qmix, saline and chlorhexidine scored more readings in the ± 0.5 mm range of the perforation site, and the difference was statistically significant. Conclusion: The most precise electronic measurements of artificial perforation were obtained in the presence of chlorhexidine or saline

Effects of MTAD on the bond strength of bioceramic root canal sealer

Aim: The aim of this in-vitro study was to investigate the effects of MTAD (a mixture of doxycycline, citric acid, and a detergent) on the bond strength of AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany) and EndoSequence BC sealer (Brasseler USA, Savannah, Georgia, USA). Materials & Methods: Eighty-four decoronated single-rooted human incisor teeth were prepared with Reciproc R25 files (VDW, Munich, Germany), and the canal was irrigated with 5 mL 1.3% NaOCl. The roots were randomly assigned to four groups (n = 21), according to the final irrigation protocol and sealer selection: Group 1: distilled water-AH Plus; Group 2: distilled water-EndoSequence BC; Group 3: MTAD-AH Plus; Group 4: MTAD-EndoSequence BC. For the final flush, in Groups 1 and 2, the root canals were irrigated with 5mL of distilled water; in Groups 3 and 4, 5mL of MTAD was used for 1 minute. After root canal obturation, specimens was embedded in an acrylic block and sectioned horizontally at three levels (coronal, middle, apical). Bond strength of sealer to root canal dentin was assessed via push-out test using a universal testing machine. Results: There were no significant differences among the groups in coronal and apical thirds. In the middle root third, Group 4 showed significantly lower push-out bond strength values than Group 2 (p=0.023). No significant difference was found between the two root canal sealers. Conclusions: Overall, MTAD final irrigation caused lower push-out bond strenght values than distilled water with no significancy.

Effect of Final Irrigating Solutions on Smear Layer Removal and Penetrability of an Epoxy Resin based Sealer into Dentinal Tubules

Introduction: During instrumentation smear layer formationoccurs on dentinal wall and for a successful root canal itsremoval is necessary. Aim of the study was to compare effectof 17% EDTA, MTAD & 18%Etidronic acid (HEBP) + 5%NaOCl, irrigating solutions on smear layer removal andpenetrability of AH Plus sealer into dentinal tubules usingscanning electron microscopy (SEM).Material and methods: Sixty single rooted mandibularpremolars, were divided into three groups (n=20).Group -I17% EDTA, Group -II MTAD, Group -III 18%Etidronic acid+5% NaOCl. The final rinse was done by 5ml of solution for2 minutes. Ten samples from each group were evaluated atmiddle and apical thirds for smear layer removal using SEM.Remaining ten samples of each group were obturated withgutta-percha & AH PLUS sealer and evaluated at 5mm abovefrom the root apex for sealer penetration using SEM.Results: At middle 3rd no difference in smear layer removalwas seen between Group –I and Group -II For apical 3rdGroup- II showed better smear layer removal than Group–I and Group- III. Thus both in middle and apical thirdsMTAD showed better smear layer removal. For mean sealerpenetration Group -II showed a highest depth of sealerpenetration i.e, 231.37±18.12µm followed by Group -I154.95±22.53µm and Group –III 125.99±17.39µmConclusion: MTAD is effective in smear layer removal fromboth middle and apical thirds. Maximum depth of sealerpenetration was seen in MTAD group followed by EDTAgroup and least in Etidronic acid group

In vitro evaluation of the antibacterial activities of different irrigants against Enterococcus faecalis / 实用口腔医学杂志

90 extracted single rooted human teeth were inoculated with E.faecalis.The cannals of the teeth were irrigated with MTAD, 5.25% NaClO,compound chlorhexidine gargle,tinidazole mouthwash,distilled H2 O(infection control)and autoclave followed by distilled H2 O(autoclaving control),respectively(n =1 5).Then E.faecalis infection of the samples were examined.The results showed that MTAD had significantly greater antibacterial effects than 5.25% NaClO,tinidazole mouthwashes,compound chlorhexidine gargle and tinidazole mouthwash(P <0.05).There was no significant difference between each 2 of the other 3 irrigants.

Antimicrobial effect of MTAD, Tetraclean, Cloreximid, and sodium hypochlorite on three common endodontic pathogens.

Objectives: The aim of this in vitro study was to evaluate the antimicrobial action of BioPure MTAD (Dentsply Tulsa Dental, Johnson City, TN), Tetraclean, Cloreximid (a mixture of Chlorhexidine (CHX) digluconate and Cetrimide), and 5.25% NaOCl (Ogna Laboratori Farmaceutici, Milano, Italy) against selected endodontic pathogens (Enterococcus faecalis, Porphyromonas gingivalis, and Prevotella intermedia). Materials and Methods: The agar plate diffusion procedure was used to observe the antimibrobial activity of irrigants. Results: Statistical analysis revealed significant effects of the different irrigants on the bacteria colonies. Treatment with 5.25% NaOCl induced a larger zone of microbial inhibition in Prevotella intermedia and Porphyromonas gingivalis (Tukey HSD post-test, P = 0.0001) when compare to MTAD, Tetraclean and CHX. Anyway, MTAD and Tetraclean were more effective to inhibit bacterial growth compared to CHX (P < 0.0001, Tukey HSD post-test). Furthermore, post hoc analysis revealed that MTAD and Tetraclean induced the largest zone of microbial inhibition of Enterococcus faecalis cultured under both aerobic and anaerobic conditions, when compared with 2% CHX and NaOCl (P < 0.0001, Tukey HSD post-test). The control group showed no microbial inhibition. Conclusion: 5.25% NaOCl showed a high antimicrobial activity against anaerobic bacteria. MTAD and Tetraclean showed a high action against both, strictly anaerobic and facultative anaerobic bacteria. Chlorexidine + Cetrimide (Cloreximid) showed the lowest antibacterial activity against both, facultative and strictly anaerobic bacteria tested.

The effect of MTAD as a final root canal irrigants on the coronal bacterial leakage of obturated root canals / 대한치과보존학회지

The purpose of this study was to evaluate the effects of MTAD, EDTA and sodium hypochlorite(NaOCl) as final irrigants on coronal leakage resistance to Enterococcus faecalis. Forty extracted human maxillary molars were used in this experiment. The teeth were randomly divided into positive control group (Group 1; n = 5), negative control group (Group 2; n = 5) and three experimental groups (n = 30). In Group 3 (n = 10), the root canals were irrigated with sodium hypochlorite. In Group 4 (n = 10) and 5 (n = 10), the root canals were irrigated with sodium hypochlorite and rinsed with EDTA and MTAD, respectively. The teeth in each group were cleaned and shaped to #40 profile with .04 taper, and obturated with gutta-percha and AH-26 root canal sealer. The coronal portion of each tooth was placed in contact with inoculum of Enterococcus faecalis in Brain Heart Infusion (BHI) culture media. Each root tip was placed in a vial containing sterile culture media. The vials were placed in anaerobic chamber and observed everyday for turbidity for 180 days. Statistical analysis was performed using Fisher's Exact Test. After 180 days, Group 3, 4, and 5 showed 7, 4 and 5 leaking samples respectively. The differences in leakage resistance were not statistically significant among Group 3, 4 and 5.