The effect of storage time on the degree of dye leakage of root-end filling materials

In-vitro evaluation of microleakage of bioceramic root-end filling materials: A spectrophotometric study

Aim

To evaluate the microleakage of newer bioceramic root-end filling materials.

Material and method

Sixty freshly extracted human single-rooted mandibular premolar teeth were selected for the study. Teeth with fractured root, cracks, anddilacerations were rejected. All teeth were cleaned with ultrasonic scalers. Standard access opening was done and root canal treatment was performed with rotary files followed by obturation. After storing in saline for a week apical 3 ​mm of the root was resected at 900 angles to the long axis of the root. Retro cavity preparation was done with ultrasonic tips. The teeth were divided into four groups of 15 specimens each. Group I - Biodentin, GroupII-Bioaggregate, Group III - MTA Plus, and Group IV - MTA. After the restoration of retro cavities of all the teeth as per manufacture instructions, two coats of nail varnish were applied to leave apical 3 ​mm. All teeth were stored in 2% methylene blue for 72 ​h followed by emersion in 65% nitric acid for the next 72 ​h for Dye extraction. The obtained supernatant solution was then centrifuged and optical density or absorbance was measured with a UV spectrophotometer.

Result

Microleakage was found to be increasing in this order: Biodentin ​< ​Bioaggregate ​< ​MTA Plus ​< ​MTA. No significant difference was found in the microleakage of Biodentin compared to that of Bioaggregate(p ​> ​0.01).

Conclusion

All materials exhibit some amount of microleakage. Biodentin shows the least microleakage among all the bioceramic material groups. Hence, Biodentin and bioaggregate are better material of choice for the retrograde filling to prevent microleakage.

Apical Microleakage of four Materials after Root End Resection (In Vitro Study)

Hermetic sealing of the apical area after root end resection is essential to the success of endodontic surgery. To compare microleakage after root end resection of the two bioceramic sealers without retrograde filling - Total Fill BC Sealer and MTA Fillapex, and two materials for retrograde filling-MTA and Biodentine, using the method of penetration of dye - 2% methylene blue. Forty eight extracted single-rooted human teeth were used in this study. The resection was made at 3 mm from the root tip at an angle of 90 degree to the long axis of the tooth. The teeth were divided into 4 groups: 1st group (n = 9) - root canal obturation with Total Fill BC Sealer without retrograde filling; 2nd group (n = 8) - root canal obturation with MTA Fillapex without retrograde filling. 3rd group (n = 10) - retrograde ultrasonic cavity preparation and filling with MTA. 4th group (n = 8) - retrograde ultrasonic cavity preparation and filling with Biodentine. The outer surface of the root was covered with two layers of varnish, with the exception of the apical 3 mm and then immersed in 2% methylene blue for 72 h. The degree of penetration of the dye is measured in millimeters. The data was entered and processed with the statistical package IBM SPSS Statistics 22.0. We reject the null hypothesis when p < 0.05. With significantly higher value is the arithmetic mean of the group with the root canal obturation with Total Fill BC Sealer without retrograde filling - 2,01 mm; versus a retrograde filling with MTA - 0,68 mm and Biodentin - 0,51 mm; and no statistically significant difference with the group root canal obturation with MTA Fillapex - 1,76 mm. In the four material microleakage dye was observed, but to varying degrees.

Sealing ability of white and gray mineral trioxide aggregate mixed with distilled water and 0.12% chlorhexidine gluconate when used as root-end filling materials

This in vitro study used dye penetration to compare the sealing ability of white and gray mineral trioxide aggregate mixed with distilled water and 0.12% chlorhexidine gluconate when used as root-end filling materials. Ninety-six single-rooted human teeth were cleaned, shaped, and obturated with gutta-percha and AH26 root canal sealer. The apical 3 mm of each root was resected, and 3-mm deep root-end cavity preparations were made. The teeth were randomly divided into 4 experimental groups, each containing 20 teeth, and 2 negative and positive control groups, each containing 8 teeth. Root-end cavities in the experimental groups were filled with the experimental materials. After decoronation of the teeth and application of nail polish, the teeth were exposed to India ink for 72 hours and longitudinally sectioned, and the extent of dye penetration was measured with a stereomicroscope. Statistical analysis showed that there were no significant differences among the 4 experimental groups.

A Systematic Review of In Vitro Retrograde Obturation Materials

The purpose of this review was two-fold: (a) to determine which retrograde obturation material(s) best prevents dye/ink penetration in vitro; and (b) to determine whether in vitro results agree with in vivo results. A MEDLINE search was conducted to identify in vitro studies published between January 1966 and October, week 4, 2003, conducted on human teeth, and published in English, German, or French language, testing the resistance to retrograde penetration of retrograde filling materials. The MEDLINE search identified 278 published articles. Of those, 115 studies examined the resistance to penetration of various retrograde filling materials, in vitro. Thirty-four studies met all the inclusion and validity criteria. The results indicate that, beyond 10 days in vitro, the most effective retrofilling materials, when measured by dye/ink penetration are: composites>glass ionomer cement>amalgam>orthograde gutta-percha>EBA. The results of these in vitro studies are not congruent with in vivo study results, suggesting a need to re-evaluate the clinical validity and importance of in vitro studies.

Effect of root-end resection and root-end filling on apical leakage in the presence of core-carrier root canal obturation

AIM

To evaluate the apical seal of canals filled with a core-carrier obturator following root-end resection with and without a root-end filling.

METHODOLOGY

Thirty single-rooted human teeth with single canals were used. Root canal treatment was performed and canals filled with a core-carrier obturation technique. The teeth were then randomly assigned to three groups (n = 10). In the first group root canal filling only was performed. After orthograde filling, the teeth of the second group were resected apically, perpendicular to the major axis of the root. In the third group after apical resection, a root-end cavity was prepared using ultrasonic diamond retrotips and the cavities filled with Super-EBA cement. During a period of 3 h and with a headspace pressure of 0.12 atm, methylene-blue solution was forced through a tube that was connected to the apical end of each tooth specimen. The coronal end of the tooth was connected to a capillary tube containing an air bubble. Leakage was evaluated by observing the distal displacement of the air bubble. The roots were then sectioned along their long axis. Using a stereomicroscope, linear dye infiltration at the dentine-cement interface was determined. Kruskal-Wallis and Mann-Whitney tests were used to compare the three groups.

RESULTS

Linear dye infiltration was significantly greater in root canals filled with the core-carrier obturators and resected apically (0.9 +/- 0.9 mm) when compared with those that had root-end fillings (0.2 +/- 0.4 mm). Air bubble displacement was not observed.

CONCLUSION

Root-end filling improves the sealing of roots with core-carrier obturation following root-end resection.

Microleakage in endodontically treated teeth: influence of calcium hydroxide dressing following bleaching

AIM

The purpose of the present study was to evaluate microleakage of a fourth generation dentine-bonding agent and composite restoration during a walking bleach treatment.

METHODOLOGY

Thirty extracted non-carious incisors were selected and conventional root canal treatment was performed. Teeth were randomly divided into 3 groups (n = 10): group A (control), access cavities were restored with a fourth generation dentine-bonding agent, and incrementally restored with composite resin; group B, a paste composed of sodium perborate and hydrogen peroxide was placed into the pulp chamber and sealed with glass ionomer cement for 7 days, teeth were then restored in the same manner as group A; group C, a paste of sodium perborate and hydrogen peroxide was placed in the pulp chamber for 7 days and then after removal of the bleaching mixture, pulp chambers were filled with a calcium hydroxide paste and cavities sealed with glass ionomer for 1 week. The cavities were then restored with bonded restorations as in groups A and B. Teeth were subjected to thermal cycling and immersed in methylene blue for 8 h. Teeth were sectioned from buccal to lingual, through the centre of the restoration, using a diamond disk. Leakage was assessed using a standard scheme, under magnification (x20). Data were submitted to statistical analysis using nonparametric Kruskal-Wallis test.

RESULTS

Groups A and C exhibited similar leakage patterns, and both demonstrated less leakage values than group B (P < 0.05).

CONCLUSIONS

It was concluded that bleaching with sodium perborate and hydrogen peroxide increases microleakage; short-term use of a calcium hydroxide medicament did not increase microleakage.

Effect of an acid environment on leakage of root-end filling materials

One hundred fifty-six single-rooted human extracted teeth received root canal treatment, apicoectomy, and ultrasonic root-end preparations. The roots were divided into six groups of 24 teeth. The groups were filled with Amalgam, Geristore, Super-EBA, Mineral Trioxide Aggregate (MTA), Calcium Phosphate Cement (CPC), or MTA with CPC matrix, respectively. Immediately after root-end filling, 12 teeth from each group were exposed to a pH of 5.0 for 24 h, and 12 teeth were exposed to a pH of 7.4 for 24 h. Twelve teeth served as controls. All teeth were exposed to Pelikan Ink for 5 days and cleared. Linear dye leakage was recorded. Data were statistically analyzed. An acid pH significantly reduced dye leakage of Geristore (0.67 vs. 3.93 mm) and MTA with CPC matrix (0.54 vs. 2.41 mm), whereas leakage of all other materials was not affected by pH. In conclusion an acid environment did not hinder the sealing ability of any of the materials tested, and enhanced the sealing ability of Geristore and MTA with CPC matrix.

Ultrasonic root-end preparation: influence of cutting angle on the apical seal

Apical resection is fundamental in obtaining a correct apical seal. The purpose of this study was to evaluate how the apical root resection angle and the cavity made by ultrasonic retrotips may influence the apical seal. A total of 48 extracted teeth were endodontically treated and sealed by guttapercha vertical compaction: 24 were resected with a 45 degrees angle and 24 with a 90 degrees one. An ultrasound source (P.M. 400 EMS) and a CT5 Scaler were used to make the retrograde cavity that was filled afterwards with EBA-zinc oxide-eugenol alumina-added cement. Apical leakage was determined using fuchsin and assessed after the roots were sectioned longitudinally. Linear dye penetration in dentin and at the interface between dentin and cement was measured with a stereomicroscope (x 12 magnification), and the results were statistically analyzed. Results showed that there was less infiltration both in dentin and in the space between the filling and the dentinal wall in the group with the 90 degrees angle, but this difference was statistically significant (p < 0.0001) only for the dentin. None of the samples showed leakage greater than the depth of the preparation. An apical cavity of 3 mm or more along the vertical axis can produce a safe and effective seal.

Microleakage of Diaket and amalgam in root-end cavities prepared using MicroMega sonic retro-prep tips

The in vitro sealing ability of the root-canal sealer Diaket when used as a root-end filling material was compared with that of amalgam using linear micro-leakage of Indian ink. Eight groups of 20 extracted teeth each were formed, plus 12 control teeth as follows: 1) root-end resection of 45 degrees bevel, root-end cavity preparation with an 008 round bur, amalgam root-end filling; 2) 45 degrees bevel, bur, Diaket; 3) 45 degrees bevel, using a sonic retro-prep tip, amalgam; 4) 45 degrees bevel, sonic, Diaket; 5) no bevel, bur, amalgam; 6) no bevel, bur, Diaket; 7) no bevel, sonic, amalgam; 8) no bevel, sonic, Diaket. Root-end cavity depths of 3 mm were prepared. Specimens were immersed in Indian ink for 2 weeks. The teeth were demineralized, rendered transparent and linear dye penetration recorded. Results showed that Diaket provided a superior seal to amalgam irrespective of the root-end preparation. The degree of bevel of the resected root-end did not influence leakage. Sonic instrumentation resulted in a larger root-end cavity than with burs.

Root end filling materials: a review

When non-surgical attempts prove unsuccessful or are contraindicated, surgical endodontic therapy is needed to save the tooth. The procedure usually consists of exposure of the involved area, root end resection, root end preparation and insertion of a root end filling material. Numerous materials have been suggested as root end filling materials. This article is a review of the literature on the suitability of various root end filling materials based on their leakage assessment, marginal adaptation, cytotoxicity, and usage test in experimental animals and humans.