mineral trioxide aggregate

Coronal discoloration is a common complication when using calcium silicate-based cements in esthetic zones. An ideal endodontic cement should provide favorable esthetic results alongside optimal biological and mechanical properties. This study aims to evaluate the discoloration of three calcium silicatebased cements—Cold Ceramic, Ortho MTA, and Retro MTA—in the presence of blood and normal saline.

In this experimental study, 48 human anterior teeth were prepared and randomly divided into six groups (n = 8) based on the type of cement (Cold Ceramic, OrthoMTA, RetroMTA) and environment (blood or normal saline). Color analysis of tooth crowns was performed using a spectrophotometer before applying the cements and at 30 and 60 days after application. Repeated measures analysis of variance was used to evaluate the effects of blood, material type, and time on discoloration (ΔE). As the data showed a non-normal distribution, the Kruskal-Wallis test was used for intergroup comparisons, and the Wilcoxon test was applied for intragroup analyses over time (P-value < 0.05).

After one month, specimens exposed to blood exhibited greater discoloration than those exposed to normal saline. All groups showed noticeable discoloration at two months, with blood exposure exacerbating the effect. Across different times and environments, OrthoMTA caused more discoloration than the other materials. However, the differences were not significant. (P-value > 0.05).

IIn all three groups, blood-exposed and normal saline environments caused clinically noticeable discoloration over time. These materials are, therefore, not recommended for use in esthetic zones. 

This study assessed the outcome of regenerative endodontic procedures (REPs) in permanent immature necrotic teeth.

This longitudinal cross-sectional study was conducted on permanent immature necrotic teeth that had undergone REPs from 2013 to 2018. The patients were contacted by phone and asked to show-up for clinical and radiographic examinations of their treated teeth. The preoperative parallel periapical (PA), 6-18-month postoperative radiographs, and clinical examination results were collected and compared. Functional presence of the respective tooth in dental arch with no need for an endodontic treatment in the follow-up sessions was considered as treatment success. Data were analyzed by paired t-test (alpha=0.05).

Twelve patients (N=16 teeth) met the inclusion criteria; of which, 9 (N=12 teeth) showed up for the follow-up. The mean age of patients was 15±8.44 years (range 10 to 23 years). Ten teeth had experienced trauma, and the remaining two were necrotic due to anomalies (Turner’s hypoplasia and supernumerary tooth). Six teeth had undergone REPs with calcium-enriched mixture (CEM) cement, 4 with Biodentine, and 2 with mineral trioxide aggregate (MTA). Eleven out of 12 teeth were functional with no clinical sign/symptom at 6-12, and 18-month follow-ups, and were considered as treatment success. Closure of apical opening was significant (P=0.049).

REPs through revascularization by using CEM cement, Biodentine, and MTA can be successful and increase the chance of completion of root development in permanent immature necrotic teeth.

The present study evaluated the antibacterial efficacy and biocompatibility of carbonated hydroxyapatite (CHA) compared to mineral trioxide aggregate (MTA).

CHA was synthesized at 0.05, 0.1, and 0.5 M concentrations. The minimal inhibitory concentration (MIC) of CHA and MTA were measured against Streptococcus mutans, Enterococcus faecalis, and Candida albicans. Afterwards, 1x107 CFU/mL of each microorganism was exposed to the concentration corresponding to the MIC of each material and the bacterial colony count was measured. The survival rate, hatching rate, heart rate, and morphology of zebrafish embryos were evaluated when exposed to CHA or MTA (n=20 embryos per group)

For S. mutans, the lowest MIC levels were found in the 0.05 and 0.5 CHA groups. The MIC value of all CHA concentrations against E. faecalis was 25 µg/ml. The lowest MIC against C. albicans was noted in the 0.1 CHA group. At the respective MIC levels, the 0.5 CHA showed the lowest colony count for S. mutans, which was significantly lower than that of MTA and 0.1 CHA groups (P<0.05). For E. faecalis, the 0.1 CHA and MTA groups had significantly lower colony count than the 0.05 CHA group (P<0.05). Regarding C. albicans, the 0.1 CHA had the lowest colony count, significantly lower than the 0.05 CHA group (P<0.05). Zebrafish embryos showed the lowest survival, hatching, and heart rates when exposed to MTA (P< 0.05).

The 0.1 and 0.5 CHA concentrations showed a favorable antibacterial efficacy against various oral microorganisms and better biocompatibility than MTA.

Vital pulp therapy (VPT) comprises a range of conservative treatment modalities aimed at preserving the vitality of the compromised dental pulp in primary and permanent teeth. This PubMed-based review comprehensively evaluates seven distinct VPT techniques; including their historical development, broad definitions, clinical protocols and treatment outcomes as evidenced by systematic reviews and meta-analyses. The VPT modalities covered in this review include stepwise excavation, indirect pulp capping, direct pulp capping, miniature pulpotomy, partial pulpotomy, full pulpotomy and partial pulpectomy. Stepwise excavation, as a minimally-invasive option, has demonstrated effectiveness in reducing the risk of pulp exposure, particularly in permanent teeth. Clinical outcomes of indirect and direct pulp capping are promising; specifically with the application of advanced calcium silicate cements. Miniature and partial pulpotomies emphasize the importance of precise definitions and standardised protocols due to their subtle differences. Full pulpotomy has emerged as a viable alternative to root canal treatment, achieving comparable success rates in managing irreversible pulpitis. While partial pulpectomy remains the most invasive approach, it has shown potential in managing complex cases, such as root resorption, through selective tissue preservation. Despite advancements in biomaterials and technique standardisation, challenges remain, including variability in clinical protocols, limited high-quality evidence, and the need for long-term studies to better evaluate anticipated outcomes. Nevertheless, emerging biotechnologies hold promise for enhancing the precision and predictability of VPT procedures in the future

This review evaluates the effectiveness of treatment modalities for immature teeth with pulp necrosis, focusing on calcium hydroxide (CH) and mineral trioxide aggregate (MTA) apexification, as well as regenerative endodontic treatments (RETs). Recent advancements and clinical outcomes are highlighted.

A comprehensive search of MEDLINE(PubMed), Embase, Cochrane Library, Scopus, and grey literature was conducted from inception to July 2024. Systematic reviews and meta-analyses (SR/MAs) assessing apexification and RET outcomes in immature teeth with pulp necrosis were included. Studies were selected based on predefined criteria, and data on study design, interventions, and outcomes were extracted. Methodological quality was evaluated using the AMSTAR-2 tool.

31 SR/MAs were included. The quality ranged from critically low to low, except one rated as high. MTA apexification was more effective than CH for faster apical barrier formation, though overall success rates were similar. MTA is preferred for its efficiency, but standardized protocols are needed, and tooth discoloration was noted as a potential complication. RET generally outperforms apexification in root maturation, with platelet concentrates like platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) showing promising results; PRP was associated with greater root length, while PRF showed superior apical healing. Variability in RET outcomes was noted due to the lack of standardized protocols. Comparative studies of RET versusapexification showed no significant differences in survival or overall success rates. RET often provides better apical closure and root development, though results vary. Both approaches are viable, but more research with standardized protocols and larger samples is needed to establish definitive clinical advantages.

MTA apexification and RET are viable alternatives to CH apexification, with RET showing greater potential for root development and apical healing. Future research should focus on developing standardized protocols and uniform RET guidelines, and evaluating long-term outcomes to establish efficacy and safety.

The current study evaluated the marginal adaptation of different endodontic sealers based on epoxy resin, mineral trioxide aggregate (MTA), and cold ceramic (CC) to intraradicular dentin using scanning electron microscopy (SEM). Forty-five extracted single-rooted teeth were obtained. After root canal instrumentation, the samples were obturated using the lateral condensation technique with gutta-percha and one of the following sealers (n=15 for each group): 1) An epoxy resin-based sealer (AH26), 2) an MTA-based sealer (Endoseal MTA), and 3) a cold ceramic-based sealer (CC sealer). A cross-section was prepared 3 mm from the apex of each tooth. Using scanning electron microscopy (SEM), we measured the average maximum distance between the root filling material and the canal walls in four sectors of the root cross-section. Data were analyzed using one-way ANOVA and post-hoc Tukey’s test (α=0.05). The average linear distance between the sealer and dentinal wall significantly differed among the three groups (P=0.001). Pairwise comparisons revealed that the mean distance in the AH26 group (11.99 ± 4.31 µm) was significantly higher than that in the CC sealer (7.25 ± 1.94 µm; P<0.001) and Endoseal MTA group (8.86 ± 3.33 µm; P=0.014). The marginal gap between the CC sealer and Endoseal MTA group was statistically comparable (P = 0.735). The CC sealer and Endoseal MTA exhibited similar marginal adaptation to root canal dentin, which was superior to the epoxy resin-based AH26 sealer. Endoseal MTA and cold ceramic sealers could be recommended for endodontic treatments to reduce the risk of reinfection.

We aimed to describe the diagnosis and treatment of an upper right central incisor with an unfavorable prognosis. A 16-year-old man with a history of severe dentoalveolar trauma with avulsion and a failed attempt at endodontic treatment of apexification, dyschromia, and severe internal root resorption was treated. The psychosocial conditions of this pediatric patient played a role in choosing the option of maintaining the incisor for alveolar preservation to plan prosthetic replacement with an osseointegrated implant in adulthood.

This study aimed to evaluate the calcium ion (Ca2+) release from apical plugs formed by three different bioceramic cements in simulated immature teeth with open apices. In this in-vitro study, 66 single-rooted lower premolar teeth were divided into three groups, each containing 22 samples, as follows: Group A: ProRoot MTA, Group B: Bio-C Repair, and Group C: Dia-Root Bio MTA. Each sample was prepared to simulate immature teeth with open apices. A 4 mm apical plug was inserted at the open apex area. Calcium ion release was measured on the 7th, 15th, and 30th days using an atomic absorption spectrophotometer. Data were analyzed using Kruskal–Wallis, and Mann-Whitney U tests at the significance level of P < 0.05. The apical plugs formed by different groups showed significant differences in Ca2+ release over 30 days (P<0.001). Group C had the highest release on days 7 (18.08 ± 0.57 ppm) and 15 (16.39 ± 0.75 ppm), whereas Group B showed the lowest levels (P < 0.05). On day 30, Group A had the highest Ca2+ release (2.36 ± 0.25 ppm), which was significantly greater than that of Groups B and C (P < 0.05). Dia-Root Bio MTA showed the highest calcium ion release on days 7 and 15, whereas ProRoot MTA exhibited the most significant release on day 30. Both Dia-Root Bio MTA and ProRoot MTA are more favorable options than Bio-C Repair for root repair in immature, non-vital teeth

To provide a continuous seal of the root canal, root‑filling material should bond to the root canal dentin, ensuring the integrity of both the root‑filling material and dentin remains in a static and functional state. The present study assessed the push‑out bond strength of mineral trioxide aggregate (MTA) and cold ceramic (CC).

In this laboratory trial study, 20 single‑rooted, extracted human teeth without caries and cracks were selected. Each tooth was mounted in cold‑curing resin. Then, 3 mm slices of mid‑root dentin were obtained from each tooth. The specimens were randomly divided into two groups (n = 10) and filled with MTA ProRoot and CC. All specimens were stored for 30 days in an incubator at 37°C and 100% humidity. The push‑out bond strength of the test materials was measured using a cylindrical punch with a 1‑mm diameter. The punch was pushed against the test specimen at a speed of 1.0 mm/min using a universal material testing machine, extruding the filling test material. The push‑out force during the test was recorded, and then, the internal surface of the teeth was examined to evaluate the mode of failure. Independent t‑test and Chi‑square were used to analyze the data. P < 0.05 was considered a significance threshold.

The mean push‑out bond strength in the CC group was 24.58 (MPa), and in MTA ProRoot, it was 23.77. No significant difference was observed between the two groups. The most frequent mode of failure in both groups was adhesive failure.

The two materials have adequate push‑out bond strength to root dentin, and there is no difference between the bond strength and mode of failure of the two materials.

Objectives:

 Recently, Cold Ceramic (CC), which is a mineral trioxide aggregate-like bio-ceramic and an essential component of calcium hydroxide, has been introduced as a potential root-end filling material. The purpose of this case series was to investigate the reliability and potential periapical healing effects of CC as a root canal-filling material.

Cases: 

In this study, six cases were described with complaints of pain and acute periapical abscess, who were managed in one visit using CC as a root canal filling material. After two weeks of follow up, they were clinically examined, which revealed no signs and symptoms in 12.33 months on average with a mean Periapical Index score of 1.33 (compared to initial mean score of 3).

 Root canal filling with cold ceramic introduces clinicians to an alternative treatment strategy that might improve the healing outcomes for patients presenting with complex and challenging endodontic conditions.

This study compared the retrievability of an epoxy resin-based sealer (AH26) and an MTA-based sealer (EndoSeal MTA) following root canal retreatment. Twenty-six extracted single-rooted human maxillary central incisors were prepared up to size F3 using the Denco Super Files III rotary system. The teeth were randomly assigned to two groups and obturated with either AH26 or EndoSeal MTA sealers, employing a single-cone technique for all samples. After one week of storage in distilled water, the filling materials were removed by Denco super files III rotary system. The residual sealer was evaluated using scanning electron microscopy (SEM) at x800 and x2000 magnifications. The statistical analysis was done by Two-way ANOVA, and a P-value less than 0.05 was considered significant. Under the two magnifications, both the type of utilized sealer and the root section assessed had a significant effect on the percentage of remaining sealer (P<0.05), but the interaction was not significant (P>0.05). The overall percentage of residual sealer was significantly lower in the EndoSeal MTA group compared to the AH26 groups as assessed under x800 (P=0.08) and x2000 (P=0.012) magnifications. In each group, the percentage of residual sealer was significantly greater in the apical than in the coronal third. The residual sealer in the AH26 group was greater than that in the EndoSeal MTA in all three root sections. The apical third section showed more sealer than the coronal section, irrespective of the sealer type used.

The present study aimed to evaluate the bond strength of Sure-Seal Root as a new bioceramic-based sealer, and compare it with other sealers, including an epoxy resin-based sealer (AH-Plus), zinc oxide eugenol (ZOE) and a mineral trioxide aggregate-based sealer (MTA Fillapex).

In this in vitro study, 40 extracted mandibular premolars were randomly assigned into 4 groups (n=10) according to the type of sealer applied as follows: Group 1: AH-Plus, Group 2: MTA-Fillapex, Group 3:  Sure-Seal Root, and Group 4: ZOE. The canals were prepared and obturated with gutta-percha and the corresponding sealer. The samples were sectioned into horizontal segments, and the push-out bond strength was determined using a universal testing machine at the coronal, middle, and apical root thirds. The data were analyzed by repeated measures ANOVA, and the significance level was set at P<0.05.

There were no significant differences in the push-out bond strength between groups in the coronal third (P>0.05). In the middle third, AH-Plus exhibited significantly greater bond strength compared to Sure-Seal Root and ZOE sealers (P<0.05), whereas MTA-Fillapex was not significantly different from the other groups (P>0.05). In the apical third, both AH-Plus and MTA-Fillapex showed significantly greater push-out bond strength than Sure-Seal Root and ZOE sealers (P<0.05).

AH-Plus sealer exhibited the highest and ZOE showed the lowest bond strength. Sure-Seal Root indicated promising bond strength results when compared to ZOE and MTA-Fillapex. The push-out bond strength of all sealers to dentin increased from the coronal to the apical third.

Objectives :

In endodontics, mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM cement) are commonly used bioceramic materials. Regenerative endodontics often involves the use of double or triple antibiotic pastes (DAP or TAP), which are effective but may cause discoloration. This study aims to examine the effectiveness of internal bleaching in addressing discoloration caused by 4 different materials.

Methods:

 This in vitro study was conducted on 40 single-rooted anterior and premolar human teeth that did not have caries, restorations, obvious discoloration, or fractures and were extracted due to periodontal disease or orthodontic treatment. The teeth were randomly assigned to 4 groups (n=10). After root canal instrumentation, the baseline color of the specimens was measured using a spectrophotometer. After applying the aforementioned materials in the canals, access cavities were sealed with glass ionomer (GI), and the color of the specimens was measured again after 1 month to calculate color change (∆E). Internal bleaching was performed with 35% hydrogen peroxide 3 times within 3 weeks, and values were calculated at each time point. Data were analyzed using paired t-tests and 1-way analysis of variance (ANOVA).

Results:

 Clinically noticeable discoloration (∆E>3.7) occurred in the MTA Angelus (∆E=4.88) and TAP (∆E=17.3) groups. The ∆E of the TAP group was significantly higher than that of all other groups (P<0.05). The discoloration was borderline detectable in the CEM group (∆E=3.89) and clinically undetectable in the DAP group (∆E=2.02). Discoloration significantly improved after 3 rounds of bleaching in the TAP group (P<0.05), as well as after 2 rounds of bleaching in the MTA (P<0.05) and CEM (P<0.05) groups. In all groups, ∆E increased after each round of bleaching.

Conclusion :

The CEM cement may yield better results with lower discoloration compared to MTA and exhibit a more favorable response to internal bleaching. For canal disinfection using antibiotic paste, DAP is a good alternative to TAP.

This study aimed to compare the effect of human blood and platelet-rich fibrin (PRF) on the surface microhardness of hydraulic calcium silicate-based cements (OrthoMTA and RetroMTA).

Two types of mineral trioxide aggregate, OrthoMTA and RetroMTA, were mixed and placed into cylindrical molds. The lower surfaces of all cements were exposed to saline. The upper surfaces of cements were exposed to human blood, PRF, or phosphate buffer saline (PBS). After storage for 7 days in fully saturated humidity at 37°C, the microhardness of cement surface exposed to blood, PRF, or PBS was measured using the Vickers microhardness test. The data were analyzed using two-way analysis of variance and post hoc Tamhane’s T2 test. The significance level was set at P<0.05.

Exposure to blood and PRF significantly decreased the surface microhardness of OrthoMTA and RetroMTA. The microhardness of PBS-contacted cements was significantly higher than that of blood or PRF groups (P<0.001). The microhardness values for OrthoMTA exposed to PRF were significantly higher than the blood group (P=0.020). There were no significant differences between RetroMTA contacted with blood or PRF groups (P=0.985). When exposed to blood or PBS, RetroMTA had a significantly higher microhardness than OrthoMTA (P<0.001 for blood, P=0.002 for PBS).

Exposure to blood or PRF decreased the surface microhardness of both cements. Blood-contaminated RetroMTA showed significantly higher surface microhardness than OrthoMTA contacted with blood. No significant difference was found between PRF-contacted OrthoMTA and RetroMTA

Statement of the Problem: 

Bond strength of furcation repair materials is an essential factor in clinical success. Studies on the effect of adding titanium dioxide (TiO2) nanoparticles on the push-out bond strength of commonly used endodontic cements for furcation perforation repair is limited.

This study aimed to evaluate the effect of adding TiO2 nanoparticles to white Portland cement (PC), white mineral trioxide aggregate (MTA), and calcium enriched mixture cement (CEM) on their push-out bond strengths.

In this in vitro study, 120 endodontically treated molars were assigned to six groups (n=20) based on the material used to repair the perforation. In three groups, the cements (white PC, white MTA, and CEM) were placed in pure form, and in the three remaining groups, 1 weight % of TiO2 was added. The push-out bond strength was measured using a universal testing machine at a strain rate of 0.5 mm/min. Data were analyzed using one-way ANOVA and post hoc Games-Howell test (p< 0.05).

One-way ANOVA showed significant differences in the mean bond strength values between the six groups (p= 0.002). The post hoc Games-Howell test showed that the bond strengths in MTA+TiO2 and PC+TiO2 groups were significantly higher than those in MTA and PC groups, respectively. However, there was no significant difference in the bond strength between CEM and CEM+ TiO2 groups.

The incorporation of TiO2 into MTA and PC increased their push-out bond strength. However, it did not affect the push-out bond strength of CEM cement.

This study aimed to evaluate the reaction of the periapical tissue to Cold ceramic and mineral trioxide aggregate (MTA) following periapical endodontic surgery.

In this experimental study, a total of 12 mandibular first, second, and third premolars of two male dogs were selected. All procedures were performed under general anesthesia. The access cavities were prepared, and the length of canals was determined. Root canal treatment was performed. A week later, periradicular surgery was performed. After osteotomy, 3 mm of the root end was cut. Then, a 3‑mm cavity was created by an ultrasonic. The teeth were randomly divided into two groups (n = 12). The root‑end cavities were filled with MTA in the first group and with Cold ceramic in the second group. After 4 months, the animals were scarified. Histological evaluation of the periapical tissues was performed. Data were analyzed using SPSS 22 and Chi‑square test and P = 0.05.

The findings showed 87.5% and 58.3% cementum formation in MTA and Cold ceramic groups, respectively, indicating a significant difference (P < 0.001). In addition, the results showed 91.7% and 83.3% bone formation in MTA and Cold ceramic groups, respectively, but the difference was not statistically significant (P = 0.6). Furthermore, the findings revealed 87.5% and 58.3% periodontal ligament (PDL) formation in MTA and Cold ceramic groups, respectively (P = 0.05).

Cold ceramic was able to induce the regeneration of cementum, bone, and PDL; hence, it can be considered as a biocompatible root‑end filling material in endodontic surgery.

The combination of mineral trioxide aggregate (MTA) and 2% chlorhexidine (CHX) has been recently introduced as an intracanal medicament. The aim of this study was to evaluate the potential cytotoxic effects of MTA mixed with 2% chlorhexidine gel on human periodontal ligament stem cells (PDLSCs) and compare it with other common endodontic regeneration medicaments.

Minimum inhibitory concentration and minimum bactericidal concentration of six experimental groups against Enterococcus faecalis was determined. The study groups consisted of RetoMTA mixed with 2% chlorhexidine gel (MTA+CHX), calcium hydroxide (CH), CH mixed with CHX gel, two concentrations of double antibiotic paste, and 2% CHX. The direct cytotoxic effect of minimum bactericidal concentration was evaluated by MTT on PDLSCs on days 1, 3, and 7. One-way ANOVA and post hoc tests were used for data analysis (P<0.05).

The viability of cells treated with MTA+CHX decreased significantly over time (P<0.05) making this group the most cytotoxic intracanal medicament on the 3rd and 7th days of treatment. On day one, the highest viability percentage was detected in the CH+CHX group followed by the CHX group. On day 3, CH+CHX and CHX groups displayed the highest viability percentage. On day 7, the highest viability was observed in the CHX group, which showed no significant difference with the control group (P=0.12).

Regarding the antimicrobial potency of intracanal medicaments at minimum bactericidal concentration levels, CHX gel appears to be the least cytotoxic drug, while MTA+CHX shows the highest reduction in viability percentage

Discoloration is an unfavorable side effect of regenerative endodontic procedures using mineral trioxide aggregate (MTA). The efficacy of home bleaching of discolored teeth with carbamide peroxide has not been well investigated, and the minimum required duration of home bleaching is still unclear. This study aimed to compare the effects of different durations of home bleaching on tooth discoloration caused by MTA.  

This in vitro, experimental study used 16 tooth blocks of bovine central incisors. To cause discoloration, white MTA was applied for 40 days in cavities drilled in blocks. The color parameters were measured at baseline and at 14, 28, and 42 days after the application of 20% carbamide peroxide using a spectrophotometer. Data were analyzed by repeated measures ANOVA and Tukey’s post-hoc test.

The color change (∆E) value was 22.9±10, 26.3±10.9, and 27.03±11 at 14, 28, and 42 days after bleaching, respectively.Significant color change occurred at 2, 4, and 6 weeks after the application of carbamide peroxide (P<0.001). The color change increased at 42 days (∆E of 3.1, or 13% compared with baseline), which was the highest amount among all time points. However, pairwise comparisons showed that it was not statistically significant (P=0.4).

It appears that 14 days is the required time for bleaching of teeth discolored by MTA. Longer bleaching times showed insignificantly higher efficacy for tooth whitening.

Different MTA brands may have different push-out bond strength (PBS) values in 10 minutes and 4 hours. Thus, this study aimed to compare the PBS of RetroMTA, OrthoMTA, and ProRoot MTA.  

In this in vitro, experimental study, 54 dentin discs with 2 mm diameter and a central lumen with 1.3 mm radius were used in each of the RetroMTA, OrthoMTA, and ProRoot MTA groups (18 discs for each group). The samples were wrapped in a moist gauze and incubated at 37°C and 100% humidity. The PBS was measured by a universal testing machine at a crosshead speed of 1 mm/minute after 10 minutes and 4 hours. The mode of failure was also categorized by using a stereomicroscope. The mean PBS of the three groups was compared using two-way ANOVA. The mode of failure was analyzed by the Chi-square test.

The interaction effect of time and material on PBS was not significant (P=0.227). At both time points, the PBS of the three groups was significantly different (P=0.001), and RetroMTA showed significantly higher PBS (P<0.014). However, the PBS of OrthoMTA and ProRoot MTA was not significantly different (P=0.695). The PBS of all materials at 4 hours was significantly higher than that at 10 minutes (P=0.001).

RetroMTA was superior to ProRoot MTA and OrthoMTA regarding the PBS after 4 hours.