Push-Out Bond Strength of Dorifill, Epiphany and MTA-Fillapex Sealers to Root Canal Dentin with and without Smear Layer

INTRODUCTION

The aim of the present experimental study was to evaluate the push-out bond strength of Dorifill, Epiphany and MTA-Fillapex sealers to root canal dentin in presence and absence of smear layer (SL).

METHODS AND MATERIALS

Sixty human single-rooted teeth were selected and divided into six groups (n=10). The canal irrigation protocol in groups 1, 3 and 5 consisted of 2.5% NaOCl during instrumentation and normal saline at the end of preparation plus a 5-min irrigation with 17% ethylenediaminetetraacetic acid (EDTA). In the remaining groups, normal saline was used for canal irrigation. The root canals were filled with Epiphany/Resilon (groups 1 and 2), Dorifill/gutta-percha (groups 3 and 4) and MTA-Fillapex/gutta-percha (groups 5 and 6). After two weeks of storage in 95% relative humidity at 37(º)C, 2 mm-thick dentin disks were prepared from coronal third of each root. The push-out bond strength test was carried out using a universal testing machine. Data were analyzed with the two-way ANOVA and post hoc Tukey's tests. Statistical significance was defined at 0.05.

RESULTS

The highest (3.06±0.38 MPa) and lowest (1.16±0.32 MPa) push-out bond strength values were recorded in Epiphany/Resilon-NaOCl/EDTA and Dorifill/gutta-percha/normal saline groups, respectively. There were significant differences in the bond strength of sealers (P<0.05). In addition, elimination of the SL significantly increased the bond strength of all sealers (P<0.05).

CONCLUSION

The Epiphany/Resilon group exhibited the highest push-out bond strength in the presence and absence of the SL. Elimination of the SL resulted in a significant increase in the bond strength of all the sealers to dentin.

Residual Antimicrobial Activity of MTAD(®) in Human Dentin After Obturation with Gutta-Percha/AH26 and Resilon/RealSeal SE at Different Time Intervals; An Ex Vivo Study

OBJECTIVES

To eliminate microorganisms that are responsible for pulpal and periapical infections and to prevent reinfection of the root canal system an effective chemomechanical preparation by irrigants with sustained antimicrobial activity is beneficial. Hereby, we evaluated the residual antibacterial activity of MTAD after canal obturation at different time intervals.

MATERIALS AND METHODS

A total of 120 human single-canalled anterior teeth were selected. The root canals were instrumented to a standardized apical size. Among all, 90 teeth received final irrigation with MTAD and were divided into three groups according to their obturation materials; i.e. gutta-percha/AH26, Resilon/RealSeal SE and positive controls. All these groups were divided into three 1-, 3- and 6-week time interval subgroups. Thirty teeth as negative control had no final irrigation with MTAD, but were obturated with gutta-percha/AH26 or Resilon/RealSealSE. Dentin powder was prepared after 1, 3 and 6 weeks. Dentin powder was exposed to Enterococcus faecalis for 24h and then cultured. Colony Forming Unit (CFU) was counted.

RESULTS

Residual antimicrobial activity of MTAD in the teeth obturated with guttapercha/AH26 was significantly higher than the teeth obturated with Resilon/RealSeal SE (p<0.001). It also showed a time dependent decrease in MTAD antimicrobial activity for all groups. The highest antimicrobial activity of MTAD was found in the 1-week positive control and 1-week gutta-percha/AH26 specimens. The lowest antimicrobial activity of MTAD was found in 6-week Resilon/RealSeal SE samples and then the negative controls.

CONCLUSION

MTAD had antimicrobial activity even at the sixth week, although it had a time-dependent decrease. Resilon/Epiphany SE significantly decreased antimicrobial activity of MTAD at all time points.

Effect of different final irrigants on bond strength of resilon/epiphany and resilon/epiphany self-etch

OBJECTIVE

To assess the effects of different final irrigants on the bond strength of bonded root filling materials, Epiphany/Resilon and Epiphany self-etch (SE)/Resilon.

MATERIALS AND METHODS

The root canals of eighty single-rooted extracted human teeth were prepared. After the smear layer was removed using 17% EDTA, the samples were randomly divided into eight groups. In groups 1 and 2, no additional irrigant was used after EDTA. In the other groups, final irrigation was performed with 2.5% NaOCl (groups 3 and 4), 2% chlorhexidine (CHX) (groups 5 and 6), and normal saline (groups 7 and 8). The root canals were obturated with Epiphany/Resilon in groups 1, 3, 5 and 7 and obturated with Epiphany SE/Resilon in groups 2, 4, 6 and 8. After the middle thirds of the roots were horizontally sectioned, the push-out bond strength of root filling materials was assessed using the universal testing machine. The data were analyzed using Mann-Whitney and Kruskal-Wallis tests. The significance level was set at p<0.05.

RESULTS

There was no significant difference between the push-out bond strength of Epiphany/Resilon and Epiphany SE/Resilon (p>0.05). Considering the irrigation protocols, final irrigation with 2.5% NaOCl was associated with a significantly lower bond strength of both filling materials than the other irrigants (p<0.05). EDTA, CHX and normal saline had similar effects on the bond strengths of filling materials (p>0.05).

CONCLUSION

Final irrigation of the root canals with 2.5% NaOCl following application of EDTA had a negative effect on the bond strength of Epiphany and Epiphany SE obturation systems.

Sealing Ability of Resilon and MTA as Root-end Filling Materials: A Bacterial and Dye Leakage Study

INTRODUCTION

Endodontic surgery is a valuable option for maintaining patient's natural dentition when previous orthograde endodontic treatments fail to succeed. Proper root-end preparation and placement of a retro-filling material are recommended for successful endodontic surgery. The objective of this experimental study was to compare sealing ability of Resilon/Epiphany system, as a potential root-end filling material, with ProRoot MTA using both dye and bacterial leakage models.

MATERIALS AND METHODS

Ninety two single-rooted extracted human teeth were decoronated and prepared endodontically. Specimens were randomly divided into four experimental groups (n = 20) and four control groups (n = 3). After removal of apical 3 mm and root-end cavity preparation, MTA, or Resilon were used to fill root end cavities. For bacterial leakage, specimens (20 for each experimental group, 3 negative, and 3 positive controls) were subjected to E. faecalis over a 70-day period. Methylene blue was used for dye leakage (the same in number as before). Using stereomicroscope (40× mag.) complete dye leakage was assessed after 72 h. Kaplan-Meier survival analysis was performed for bacterial leakage. The data was analyzed using t-test and Chi-square analysis (α = 0.05).

RESULTS

All of the positive controls and none of negative controls revealed leakage. Result of log rank test showed no significant difference between MTA and Resilon in time of bacterial leakage at the end of the 70 days (P > 0.05) There was also no statistical difference in complete dye leakage for both groups (P > 0.05).

CONCLUSION

Leakage occurred in both MTA and Resilon as root-end filling material but the difference was not statistically significant. Resilon might be noticed as a potential root-end filling material if good isolation is attainable.

The Effect of Blood on Apical Microleakage of Epiphany and AH26: An In Vitro Study

 

INTRODUCTION

Blood contamination of the canal during preparation can be a major problem in endodontics; this may result in apical microleakage. The aim of this in vitro study was to evaluate the effect of blood on apical microleakage of a resin-based root canal sealer (AH26) and a polymer-based root canal sealer (Epiphany).

MATERIALS AND METHODS

In this experimental study, 50 decoronated central incisors and canine teeth were prepared by RaCe rotary system and randomly divided into 4 groups (n=10). Groups A1 and A2 were obturated by Epiphany/Resilon and AH26/Gutta-percha, respectively. The obturations were performed with a single cone technique after drying root canals. In B1 and B2 groups, the test groups, 0.02cc citrated human blood was injected into dried root canals and they were obturated in the same manner. Ten specimens were served as positive and negative controls (n=5).The apical leakage was measured by means of a computerized fluid filtration method after 1 day and 3 weeks. The data was analyzed by One-Sample Kolmogorov-Smirnov, Independent Sample t-test and univariate analysis. Statistical significances were preset at α=0.05.

RESULTS

There was no significant difference in apical microleakage of the two sealers after 1 day and 3 weeks in dry and blood environment (P>0.05). Sealer and environment had no interaction (P>0.05).

CONCLUSION

Blood contamination has no significant effect on the apical microleakage of Epiphny and AH26.