Apical Leakage of Root-End Placed SuperEBA, MTA, and Geristore Restorations in Human Teeth Previously Stored in 10% Formalin

Push-Out Bond Strength of EndoSeal Mineral Trioxide Aggregate and AH Plus Sealers after Using Three Different Irrigation Protocols

OBJECTIVE

 The current study was designed to assess the bonding strength of EndoSeal MTA and AH Plus sealers after using three irrigation protocols as follows: (1) 17% Ethylenediamine tetraacetic acid, (2) 7% maleic acid, and (3) 37% phosphoric acid.

MATERIALS AND METHODS

 Push-out bond strength was evaluated for 60 middle root slices of 1-mm thickness each. They were horizontally cut from freshly extracted single-rooted human teeth. A hole in the root canal was made using a carbide round bur of 1.1 mm in diameter in a middle third root slice. Specimens were dipped in 2.5% NaOCl, and then they were grouped into three groups; G1: 17% EDTA, G2: 7% maleic acid, and G3: 37% phosphoric acid as a final irrigant for 3 minutes. Each group was subdivided into two subgroups, according to the type of sealer, either EndoSeal MTA or AH Plus.

STATISTICAL ANALYSIS

 After the full set of the sealer, the bond strength was evaluated with the push-out test by applying a force to each slice using a plunger with a 1-mm diameter. The one-way Tukey's post hoc test, analysis of variance (ANOVA) test, and Student's t-test were utilized to gather data and statistically evaluate it.

RESULTS

 The irrigation protocol used exhibited significant influence on the bond strength of EndoSeal MTA and AH Plus sealers. AH Plus sealer subgroups showed the highest bond strength with 7% maleic acid, followed by 37% phosphoric acid, and 17% EDTA. While in the EndoSeal MTA sealer subgroups, the highest bond strength was shown with the 17% EDTA followed by 7% maleic acid and 37% phosphoric acid, respectively.

CONCLUSION

 The present study revealed that the type of the final irrigant significantly impacts the bond strength of the sealer used. The AH Plus sealer bond strength was improved by using the 7% maleic acid as a final irrigant. In contrast, the EndoSeal MTA sealer showed the best results with the 17% EDTA as a final irrigant.

Marginal gaps and internal voids after root-end filling using three calcium silicate-based materials: A Micro-CT analysis

This study evaluated the 3D quality of root-end filling, assessing the presence (volume and percentage) of marginal gaps and internal voids formed after retro-filling with three calcium silicate-based materials: MTA Angelus (Angelus Soluçoes Odontologicas, Londrina, PR, Brazil), Biodentine (Septodont Ltd., Saint Maur-des-Faussés, France) and Neo MTA Plus (Avalon Biomed Inc., Bradenton, Florida, US). Thirty human, extracted, single rooted teeth were used. Orthograde root canal treatment, root resection (3mm shorter than the apex) and retrograde cavity preparation with ultrasonic tips were performed. Teeth were divided into 3 groups (n =10 each) following a stratified randomization according to the initial volume of the root-end cavity. After retrofilling, samples were stored for 7 days. Then, two rounds of micro-CT scans were performed: soon after root-end preparation (with the cavity still empty) and 7 days after root-end filling. Marginal gaps, internal voids volume (mm3 and %), as well as, the overall defects (sum of gaps and voids) were evaluated. Statistics compared the three groups in relation to those defects. There was not statistical difference between groups regarding the marginal gaps (P≥ 0.05), the internal voids (P≥ 0.05), and the overall defects (P≥ 0.05). Median (mm3) and % of overall air-entrapment defects (gaps and/or voids) was: 0.004mm3 and 1.749% for MTA Angelus, 0.018mm3 and 6.660% for Biodentine, and 0.012mm3 and 4.079% for Neo MTA Plus. All materials had gaps and/or voids. No differences were found between MTA Angelus, Biodentine and Neo MTA Plus.

Evaluation of Extrusion and Apical Seal of Thermafil™ Obturation with and without MTA as an Apical Barrier in Comparison with Lateral Condensation Technique: An In Vitro Study

AIM AND OBJECTIVE

This study aimed to compare the apical sealing ability and periapical extrusion in the Thermafil™ obturation technique, with and without an apical barrier of MTA, with lateral condensation technique.

MATERIALS AND METHODS

Sixty freshly extracted human central incisors were instrumented with the crown down technique and divided into three experimental groups. Group I: lateral condensation technique obturation, group II: Thermafil obturation (DENTSPLY Tulsa), and group III: this group was obturated into two parts; first MTA (ProRoot) was placed in apical 3 mm and later the remaining canal was obturated with Thermafil™ obturation technique (DENTSPLY Tulsa). AH Plus sealer was used in all the groups. Specimens of all the groups were layered with nail paint excluding the apical 3 mm. Twenty-four hours later, all the teeth were suspended in Black India ink for 48 hours. Finally, all the teeth were decalcified, rendered transparent and linear dye leakage and periapical extrusion was measured using ×60 magnification of stereomicroscope with an in-built ruler.

RESULTS

A Chi-square test done to evaluate periapical extrusion showed there was a significant difference found among all the groups (p < 0.05), whereas in case of linear apical dye leakage using a Student's "t" test showed there was no significant difference among all the groups (p > 0.05).

CONCLUSION

Despite showing apical leakage, the thermo-plasticized gutta-percha obturation technique can be advantageous when used with MTA as an apical barrier since there is no scope for apical extrusion along with the benefit of three-dimensional obturation of the root canal system when compared with the lateral condensation technique.

HOW TO CITE THIS ARTICLE

Rao AS, Mathur R, Shah NC, et al. Evaluation of Extrusion and Apical Seal of Thermafil™ Obturation with and without MTA as an Apical Barrier in Comparison with Lateral Condensation Technique: An In Vitro Study. Int J Clin Pediatr Dent 2020;13(S-1):S40-S44.

The effect of protocol for disinfection of extracted teeth recommended by center for disease control (CDC) on microhardness of enamel and dentin

Background

According to the guideline of the United States center for disease control (CDC), the extracted teeth should be sterilized by autoclaving or storage in 10% formalin before using for educational or research purposes. The objective of this study was to evaluate the effect of this protocol on microhardness of dentin and enamel.

Material and Methods

Thirty extracted single-root teeth were used in this study. The crowns were resected, and the roots were longitudinally sectioned into two halves. The Vickers microhardness (VHN) of specimens was measured on polished canal dentin and buccal enamel surfaces. The crowns were randomly divided into three groups (n=10). Group 1 and 2 were sterilized using autoclave and formalin, respectively while group 3 (control) was stored in synthetic tissue fluid. The root halves were also randomly divided into 3 groups (n=20) which were treated as mentioned above for crown samples. Following sterilization, VHN of samples was measured again. ANOVA and paired samples t-tests were used to analyze the data.

Results

Autoclaving caused a significant reduction in microhardness of dentin (P <0.001, 12.04% decreases in VHN). However, there were no significant differences for before and after sterilization within other groups.

Conclusions

Based on the results of this study, the CDC protocol is recommended in studies related to enamel microhardness. However, Autoclaving is not an appropriate sterilization method in studies related to dentin microhardness. In these studies, two-week immersion in 10% formalin is recommended.

Key words:Autoclave, CDC, extracted teeth, formalin, microhardness, sterilization.

Evaluation of Apical Microleakage in Open Apex Teeth Using MTA Apical Plug in Different Sessions

Aim. To compare microleakage of apexification using MTA in one or two sessions. Materials and Methods. 88 single rooted teeth were prepared and divided into two groups then received MTA apical plug. In the first group, the teeth were immersed in normal saline for 24 hours and then backfilled with guttapercha and AH26 sealer. In the second group, the teeth were obturated immediately after receiving apical plug. Four positive and four negative controls were selected. All specimens were placed in 1% methylene blue and decalcified in 5% nitric acid and finally were placed in methyl salicylate until getting transparent. All teeth were visualized for assessment of dye penetration under stereo dissecting microscope. Results. 36 and 35 teeth showed dye leakage in the first and second groups. Dye penetration into the entire canal length was confirmed in the positive control group, and in the negative control group no dye penetration was seen. Mean dye penetration in the first and second group was 5813 and 9152  μ m. t-test revealed a significant difference between dye penetrations of two groups (P < 0.05). Conclusion. MTA requires adequate time for setting in the presence of the moisture, and final obturation should be delayed until final setting of MTA.

Comparative analysis of the effect of autoclaving and 10% formalin storage on extracted teeth: A microleakage evaluation

Aim:

This study compares the effect of formalin and autoclaving the tooth samples by evaluating microleakage in-vitro.

Materials and Methods:

Forty-five extracted human permanent incisor teeth were taken and randomly divided into three groups (with different methods of storage and disinfection) with 15 teeth each: Group 1: Control-extracted teeth in this group were stored in normal saline, Group 2: the extracted teeth in this group were stored in 10 % formalin for two weeks and Group 3: the extracted teeth were Autoclaved at 121°C, at 15 psi pressure for 40 minutes. In all the groups after the specified storage period, class V cavities were prepared on the labial surface and restoration was performed with Z100 restorative. Finished and polished samples were subjected to 500 cycles of thermocycling. All specimens were immersed in methylene blue for 24 hours. After sectioning, the margins of restoration were evaluated for dye leakage at 10 X magnification, using an optical microscope. Data were subjected to nonparametric Kruskal Wallis one way analysis of variance. Inter-group comparisons were performed using the Mann Whitney test (P < 0.05).

Results:

The authors found that the microleakage in the formalin group was considerably lower than that in the control group. The autoclave group showed slightly higher mean microleakage, but the difference was not statistically significant.

Conclusion:

Both autoclaving and formalin storage affect, to a varying degree, the microleakage values in vitro. The results in the autoclaving group matched those of the control group more closely, with only a slight difference.

Super-EBA and IRM as root-end fillings in periapical surgery with ultrasonic preparation: a prospective randomized clinical study of 206 consecutive teeth

OBJECTIVE

This study evaluated the treatment outcome after periapical surgery with the use of 2 different retrograde root-filling materials and the influence of 3 pre- and perioperative variables on the periapical healing.

STUDY DESIGN

Two hundred six teeth in 164 patients were randomly allocated to receive either IRM or Super-EBA as a retrograde root-end seal. The teeth were reviewed 12 months after surgery. The influence of lesion size, lesion type, and orthograde root filling quality on healing was analyzed.

RESULTS

One hundred ninety-four teeth in 153 patients were reviewed. Radiologic evaluation and clinical examination revealed 91% success rate for the IRM group and 82% for the Super-EBA group. There was no statistical significance in the healing outcome between the 2 groups (Fisher exact test). The analyzed pre- and perioperative variables had no significant influence on the treatment outcome (Z test).

CONCLUSIONS

Both retrograde materials tested in this study can serve as a root-end seal in periapical infected teeth, according to the results of the healing outcome after 12 months' follow-up.

The comparison of MTA, Geristore® and Amalgam with or without Bioglass as a matrix in sealing the furcal perforations (in vitro study)

AIM

The objective of this in vitro was to assess the sealing ability of MTA, Geristore®, and amalgam with and without Bioglass as a matrix used to repair furcation perforations in mandibular molars by using dye penetration.

MATERIALS AND METHODS

One hundred mandibular molars were randomly divided into six experimental groups. Five teeth with perforation were used as positive control while five teeth without perforation were used as negative control group. Furcal perforations were made in the teeth. Perforations were repaired with amalgam in group 1, amalgam and Bioglass in group 2, MTA in group 3, MTA and Bioglass in group 4, Geristore® in group 5, and Geristore® and Bioglass in group 6. All repairing materials were allowed to set for 72 h. Leakage at the repaired sites was then evaluated using dye penetration and clearing technique under stereomicroscope.

RESULTS

The perforations repaired with MTA and Geristore® leaked significantly less than amalgam (p = 0.000). Bioglass reduced sealing ability of MTA and Geristore® significantly (p = 0.000, p = 0.019), while reduced the sealing ability of amalgam insignificantly (p = 0.78).

CONCLUSION

MTA and Geristore® have shown acceptable sealing ability in furcal perforation in comparison to amalgam while Bioglass as a matrix beneath them has reduced their sealing ability.

Periapical surgery using ultrasonic preparation and thermoplasticized gutta-percha with AH Plus sealer or IRM as retrograde root-end fillings in 160 consecutive teeth: a prospective randomized clinical study

OBJECTIVE

The aim of this study was to evaluate the healing outcome after periapical surgery with an ultrasonic cleaning technique in conjunction with the use of either of 2 different retrograde root-filling materials in teeth with apical periodontitis.

STUDY DESIGN

One hundred sixty teeth in 139 consecutive patients were randomly allocated into 2 groups receiving either IRM or thermoplasticized gutta-percha (GP) with AH Plus sealer as a retrograde root-end seal. The patients were reviewed 12 months after surgery. The results were analyzed with Fisher exact test.

RESULTS

One hundred forty-seven teeth in 131 patients were reviewed. Radiologic evaluation and clinical examination showed an 85% success rate for the IRM group and 90% for GP group. There was no statistical significance between the 2 groups.

CONCLUSION

Both tested materials, IRM and GP, are suitable as retrograde root-end filling materials in conjunction with ultrasonic root-end preparation according to the results of the healing outcome after 12 months follow-up.