Evaluation of calcium silicate cement bond strength after using gutta-percha solvents

OBJECTIVES

To determine the effect of different gutta-percha solvents (chloroform, Endosolv E, orange oil, and eucalyptol) on the push-out bond strength of calcium silicate cements (CSCs; white mineral trioxide aggregate [WMTA]; capsule-form mineral trioxide aggregate [CMTA], and Biodentine).

MATERIALS AND METHODS

One hundred and fifty extracted single-rooted human mandibular premolars were sectioned into 3-mm-thick slices. The canal lumens were enlarged for 1.35-mm-diameter standardized cavities. The samples were randomly divided into five groups (n = 30) according to the solvent type: G1, chloroform; G2, Endosolv E; G3, eucalyptol; G4, orange oil; G5, no solvent (control). After application of the solvents for 5 min, the specimens were divided into three subgroups (n = 10): (i) WMTA, (ii) CMTA, and (iii) Biodentine. The push-out bond strength was measured. Two-way ANOVA analysis of variance and post hoc Tukey tests were used for analyses (P = 0.05).

RESULTS

The highest push-out bond strength was observed in the Biodentine (P < 0.05), and the values of WMTA and CMTA were not significantly different in all solvent groups (P > 0.05). There were no statistically significant differences among the gutta-percha solvents and control group in WMTA (P > 0.05).

CONCLUSIONS

Gutta-percha solvents used during retreatment decreased the bond strength of Biodentine and CMTA to root dentin. The bond strength of WMTA was not affected by the use of gutta-percha solvents.

Effect of double antibiotic and calcium hydroxide pastes on dislodgement resistance of an epoxy resin-based and two calcium silicate-based root canal sealers

OBJECTIVES

The purpose of the present study was to determine the dislodgement resistance of AH Plus, MTA Fillapex, and Total Fill BC sealer to root canal dentin walls following placement of calcium hydroxide (CH) or double antibiotic paste (DAP) medicaments.

MATERIALS AND METHODS

Root canals of 90 single-rooted human mandibular premolar teeth were instrumented with Reciproc rotary instruments to a size R50. The teeth were randomly divided into two experimental groups: those receiving an intracanal medicament with either CH or DAP and a control group (n = 30). After 3 weeks, the medicaments were removed by irrigation with 5 mL of 2.5 % NaOCl, 5 mL 17 % EDTA, and 5 mL distilled water under sonic agitation. Each group was then subdivided into three subgroups (n = 10), and the canals were filled with either AH Plus, MTA Fillapex, or Total Fill BC sealer. After 1 week, a push-out test was applied to the specimens and the results were analyzed using one-way analysis of variance (ANOVA) and post hoc Tamhane's tests.

RESULTS

Regardless of the type of intracanal medicament used, Total Fill BC Sealer and MTA Fillapex showed the highest and lowest bond strength, respectively (P < 0.05). The use or absence of medicaments did not significantly affect the dislodgment resistance of root canal fillings (P > 0.05). Prior CH placement improved dislodgement resistance of all sealers without statistical difference (P > 0.05). Adhesive failure between core and sealer was the most frequent failure mode.

CONCLUSIONS

Prior application of CH or DAP did not significantly affect the adhesion of the AH Plus, MTA Fillapex, and Total Fill BC Sealers.

CLINICAL RELEVANCE

There is a little information about the influence of antibiotic medicaments on the bond strength of root canal sealer. These findings suggest that the use of DAP does not affect the adhesion strength of AH Plus, MTA Fillapex, and Total Fill BC Sealers.

Fracture resistance of immature teeth filled with mineral trioxide aggregate, bioaggregate, and biodentine

Objective:

The purpose of this study was to evaluate fracture resistance of teeth with immature apices treated with coronal placement of mineral trioxide aggregate (MTA), bioaggregate (BA), and Biodentine.

Materials and Methods:

Forty-one freshly extracted, single-rooted human premolar teeth were used for the study. At first, the root length was standardized to 9 mm. The crown-down technique was used for the preparation of the root canals using the rotary ProTaper system (Dentsply Maillefer, Ballaigues, Switzerland) of F3 (30). Peeso reamer no. 6 was stepped out from the apex to simulate an incompletely formed root. The prepared roots were randomly assigned to one control (n = 5) and three experimental (n = 12) groups, as described below. Group 1: White MTA (Angelus, Londrina, Brazil) was prepared as per the manufacturer's instructions and compacted into the root canal using MAP system (Dentsply Maillefer, Ballaigues, Switzerland) and condensed by pluggers (Angelus, Londrina, Brazil). Group 2: The canals were filled with DiaRoot-BA (DiaDent Group International, Canada). Group 3: Biodentine (Septodont, Saint Maur des Fosses, France) solution was mixed with the capsule powder and condensed using pluggers. Instron was used to determine the maximum horizontal load to fracture the tooth, placing the tip 3 mm incisal to the cementoenamel junction. Mean values of the fracture strength were compared by ANOVA followed by a post hoc test. P < 0.05 was considered statistically significant.

Results:

No significant difference was observed among the MTA, BA, and biodentine experimental groups.

Conclusion:

All the three materials tested, may be used as effective strengthening agents for immature teeth.