Comparative study of the pure AH Plus sealer and its combination with triple antibiotic paste at different concentrations on Enterococcus faecalis bacteria.

Background: In this study, the effects of pure AH Plus sealer and its combination with triple antibiotic paste at different concentrations on Enterococcus faecalis bacteria have been investigated. Materials and Methods: This in vitro study was accomplished by the means of a triple antibiotic paste combination (minocycline, metronidazole, and ciprofloxacin) at different concentrations (0%, 1%, 5%, 10%, and 25%) with AH Plus sealer on E. faecalis bacteria. Sealers were set in an incubator for 1 h, 1 day, 3 days, and 7 days, and then 10 µL of bacteria solution was placed on all samples except the negative control group. After drying for 1 h, 250 µL brain-heart infusion broth culture medium was added, and it was cultured in solid media. Direct contact test technique was performed, and the obtained data were analyzed by 1-way ANOVA, 2-way ANOVA, 3-way ANOVA, and post hoc test least significant difference. It should be noted that the data were evaluated at the significance level of P < 0.05. Results: The average of colony-forming unit (CFU)/mL illustrated that there were no significant differences between fresh antibiotic-sealer combination, 1-day set, and 3-day set (P = 0.525), while in sealer with 7-day set, the average of CFU/mL was notably lower than other sets (P < 0.001). The outcomes revealed a considerable variation by passing time and the number of CFU/mL was remarkably reduced (P < 0.05). The data suggested that, by increasing the concentration, the average of CFU/mL was decreased, whereas the average of CFU/mL did not have significant differences in all concentrations of the antibiotic-sealer combination compared to pure sealer (P < 0.05). Conclusion: The concentration of 1% triple antibiotic in combination with root canal sealer may become a crucial factor for inhibiting the growth of remaining bacteria.

Immediate and Delayed Post Space Preparations in Endodontically Treated Teeth: A Scoping Review.

BACKGROUND: The aim of the present review was to identify the effect of the post-space preparation (PSP) timing (immediate or delayed) on endodontically treated teeth. METHODS: All studies in any language that compared the effect of immediate versus delayed PSP on the outcomes of an endodontically treated tooth were searched in PubMed, Scopus, Web of Science, Cochrane, ProQuest, WorldCat, and Google Scholar databases by two independent researchers until February 12, 2022. Studies assessing merely the immediate or delayed PSP were excluded. A descriptive analysis was performed to evaluate the study design and the characteristics of the included studies. RESULTS: The initial search yielded 2612 records, of which 68 were included. Except for one randomized controlled trial, all were in vitro. The evaluated variables were apical/coronal microleakage (n = 48/n = 1), post-bond strength (n = 8), bacterial infiltration (n = 7), presence of voids (n = 3), apical extrusion and residual of filling material (n = 1), and post-operative pain (n = 1). The number of publications had steady growth per year and fast growth per decade. "Post-space preparation" was the most popular keywords. CONCLUSIONS: The present review highlights the need for further investigations due to the various design of studies, controversial results, and an inadequate number of randomized controlled trials. TRIAL REGISTRATION: Retrospectively registered. Open Science ( https://doi.org/10.17605/OSF.IO/2YTM6 ).

Clinical and histological response of human pulp tissue to direct pulp capping with mineral trioxide aggregate, Biodentine and propolis.

Background: This study clinically and histologically compared the human pulp response to direct pulp capping (DPC) with mineral trioxide aggregate (MTA), Biodentine, and propolis in 2 months. Materials and Methods: In this clinical trial evaluated 41 premolars candidate for extraction due to orthodontic purposes of patients between 15 and 25 years of age. A group of 5 was separated randomly as the negative control. The remaining teeth were randomly divided into three experimental groups of 12 after mechanical exposure of the pulp by bur in high-speed handpiece under air and water spray. The exposed areas were capped with MTA, Biodentine, or propolis. Glass ionomer was applied as base over the cap. The teeth were restored with composite resin. Patients were recalled in 2 months for clinical and radiographic examinations and also pulp vitality test. Teeth were then extracted. Slides were prepared and tissue sections were evaluated for the presence and severity of inflammation, dentinal bridge, and continuity. Data were analyzed using the Chi-square and Fisher's exact tests. Results: The clinical success rate was 100% in the MTA and 91.7% in both the propolis and Biodentine groups. The presence and severity of pulpal inflammation and dentinal bridge formation were similar in all the experimental groups (P > 0.05). Dentinal bridge formation was similar in the MTA and Biodentine groups and was higher than in the propolis group. Continuation of dentinal bridge in the MTA group was significantly higher than that in the Biodentine and propolis groups (P < 0.05). Conclusion: MTA, Biodentine, and propolis are equally effective for DPC.

Micro-Computed Tomographic Assessment of Microcrack Formation before and after Instrumentation of Curved Root Canals with Neoniti Rotary Files.

The aim of this study was to assess the microcrack formation of moderately and severely curved root canals following instrumentation with Neoniti rotary files using micro-computed tomography. This in vitro study evaluated 18 extracted sound mandibular molars with two separate mesial canals and foramina in two groups (n = 9) with 5−20° (moderate) and 20−40° (severe) root canal curvature. The number of microcracks in the root canal walls was counted at baseline by micro-CT. Subsequently, the root canals were instrumented with 0.20/0.06 v Neoniti files as single files with a torque of 1.5 Ncm and a speed of 400 rpm. The number of microcracks was counted again postoperatively on micro-CT images using Amira software. Statistical analysis was performed using the Shapiro−Wilk test, Levene's test and repeated-measures ANOVA (α = 0.05). The mean number of microcracks significantly increased postoperatively in both the moderately curved (11.59 ± 9.74 vs. 8.2 ± 7.4; p = 0.001) and the severely curved (13.23 ± 5.64 vs. 7.20 ± 5.94; p < 0.001) groups. However, the differences between the two groups were not significant (p = 0.668). Based on the results obtained, it can be stated that the instrumentation of moderately and severely curved root canals with Neoniti rotary files increases the number of microcracks. However, the higher degree of curvature does not necessarily translate to a higher number of microcracks after root canal instrumentation with this specific rotary system and methodological procedures.

Comparison of full rotation and reciprocating movements in regaining apical patency during endodontic retreatment.

BACKGROUND: This study aimed to compare the continuous rotation and reciprocating movements of rotary files in achieving apical patency in root canal retreatment. MATERIALS AND METHODS: This in vitro, experimental study evaluated 64 extracted mandibular molars. The teeth were prepared up to F3 with ProTaper Universal and obturated using lateral compaction technique. The teeth were divided into four groups (n = 16) based on the mesiobuccal canal curvature (Schneider's method) and type of rotational movement. Groups 1 and 2 included straight canal teeth retreated with WaveOne Gold and ProTaper Universal Retreatment system, respectively. Groups 3 and 4 included teeth with moderately curved root canals retreated with WaveOne Gold and ProTaper Universal, respectively. Apical patency was ensured by observing the tip of a hand K-file at the apical foramen. Data were analyzed using the Fisher's exact test. P < 0.05 was considered statistically significant. RESULTS: Apical patency was successfully achieved in all 16 teeth in group 1 (100%) and 15 teeth in group 2 (93.75%). No significant difference was noted between continuous rotation and reciprocating movements in straight canals (P = 1.00). Apical patency was successfully achieved in 15 teeth in group 3 (93.75%) and 12 teeth in group 4 (75%). No significant difference was noted between continuous rotation and reciprocating movements in moderately curved canals either (P = 0.333). CONCLUSION: Both continuous rotation and reciprocating movements are equally effective in achieving apical patency in straight or moderately curved mesiobuccal canal of mandibular molars.

In vitro antimicrobial activity of mineral trioxide aggregate, Biodentine, and calcium-enriched mixture cement against Enterococcus faecalis, Streptococcus mutans, and Candida albicans using the agar diffusion technique.

BACKGROUND: This study assessed the antimicrobial activity of Biodentine, mineral trioxide aggregate (MTA), and calcium-enriched mixture (CEM) cement against Enterococcus faecalis, Streptococcus mutans, and Candida albicans. MATERIALS AND METHODS: In this in vitro study, microbial suspensions were inoculated onto agar plates. The antimicrobial effects of MTA, Biodentine and CEM cement were assessed against E. faecalis, S. mutans, and C. albicans by the agar diffusion test. In each experimental group, 7 plates containing 3 wells were prepared and immediately filled with freshly mixed cements. Positive and negative control plates were prepared with/without the bacterial suspension, respectively. After 2 h of preincubation at room temperature, the plates were incubated at 37°C for 24 h. The diameter of growth inhibition zones was measured after 24 h. Data were analyzed using ANOVA and Tukey's test (α = 0.05). RESULTS: Biodentine showed strong antimicrobial activity against all three microorganisms with an average inhibition zone of 9.10 mm. The inhibitory effect of Biodentine on E. faecalis and C. albicans was significantly superior to that of the other two cements (P < 0.05). MTA and CEM cement showed significantly higher antimicrobial activity against S. mutans (P < 0.05). The antimicrobial effects of Biodentine on S. mutans and E. faecalis were significantly greater than on C. albicans (P < 0.05). CONCLUSION: All cements revealed antimicrobial properties against the tested microbial strains. Biodentine had stronger antimicrobial effects against E. faecalis and C. albicans compared with MTA and CEM cement. Furthermore, the largest inhibition zones around all three cements belonged to S. mutans.

Comparison of the microleakage of mineral trioxide aggregate, calcium-enriched mixture cement, and Biodentine orthograde apical plug.

BACKGROUND: One-visit apexification is a treatment of choice in necrotic immature open apex teeth. Calcium silicate base materials are suitable for this method. The purpose of this study was to investigate and compare the sealing efficiency of Biodentine, mineral trioxide aggregate (MTA) ProRoot, and calcium-enriched mixture (CEM) cement orthograde apical plug using bacterial leakage method. MATERIALS AND METHODS: In this in vitro study a total of 70 extracted maxillary incisors were cleaned and shaped. A 1.1-mm standardized artificially open apex was created in all samples. The teeth were randomly divided into three experimental groups of 20, and two negative and positive control groups of 5. In experimental groups, 4-mm thick apical plugs of ProRoot MTA, CEM cement, or Biodentine were placed in an orthograde manner. Negative control samples were completely filled with MTA while positive control samples were left unfilled. Sealing efficiency was measured by bacterial leakage method, and results were analyzed by Kaplan-Meier and Chi-square tests. The level of significance was set at 0.05. RESULTS: The highest number of turbidity was recorded for ProRoot MTA samples, while the lowest for Biodentine. There was a significant difference in the number of turbidity between ProRoot MTA and Biodentine groups (P < 0.001), but there was no significant difference between CEM cement and Biodentine (P = 0.133) and ProRoot MTA (P = 0.055). CONCLUSION: Within the limitation of this in vitro study, Biodentine showed promising results as a substance with good-sealing efficiency.

In vitro comparison of shear bond strength of a flowable composite resin and a single-component glass-ionomer to three different pulp-capping agents.

BACKGROUND: Various materials are used for vital pulp capping and the bond strength of restorative materials to these pulp-capping agents significantly affects the success rate of vital pulp therapy. OBJECTIVES: The aim of this study was to determine the shear bond strength of a flowable composite resin and a single-component glass-ionomer to mineral trioxide aggregate (MTA), calcium-enriched mixture (CEM) cement and BiodentineTM as pulp-capping agents. MATERIAL AND METHODS: Seventy-two cylindrical acrylic resin blocks, with a central hole 4 mm × 2 mm, were prepared. Mineral trioxide aggregate, CEM cement and Biodentine were placed in the cavities (n = 24 in each group) and incubated for 24 h. The blocks were subdivided into the composite resin and glassionomer subgroups. Cylindrical plastic molds, measuring 3 mm in height and diameter, were used to place the restorative materials on the samples. The shear bond strength test was performed at a strain rate of 1 mm/min in a universal testing machine. The samples were evaluated under a stereomicroscope at ×25 magnification for fracture modes. The data was analyzed with the one-way analysis of variance (ANOVA) and Tukey tests. RESULTS: The maximum and minimum mean shear bond strength values were recorded in the Biodentinecomposite resin (4.77 MPa) and MTA-glass-ionomer (2.20 MPa) groups, respectively. There were significant differences in the mean shear bond strength values of MTA, CEM cement and Biodentine to the composite resin and glass-ionomer (p < 0.001). CONCLUSIONS: A composite material may be preferable for definitive filling after pulp capping with Biodentine.

Effects of endodontic tri-antibiotic paste on bond strengths of dentin adhesives to coronal dentin.

OBJECTIVES: The aim of this study was to evaluate the effects of tri-antibiotic paste (TAP) on microtensile bond strengths (MTBS) of dental adhesives to dentin. MATERIALS AND METHODS: Sixty extracted molars had their occlusal surfaces flattened to expose dentin. They were divided into two groups, i.e., control group with no dentin treatment and experimental group with dentin treatment with TAP. After 10 days, specimens were bonded using self-etch (Filtek P90 adhesive) or etch-and-rinse (Adper Single Bond Plus) adhesives and restored with composite resin. Teeth were sectioned into beams, and the specimens were subjected to MTBS test. Data were analyzed using two-way ANOVA and post hoc Tukey tests. RESULTS: There was a statistically significant interaction between dentin treatment and adhesive on MTBS to coronal dentin (p = 0.003). Despite a trend towards worse MTBS being noticed in the experimental groups, TAP application showed no significant effect on MTBS (p = 0.064). CONCLUSIONS: The etch-and-rinse adhesive Adper Single Bond Plus presented higher mean bond strengths than the self-etch adhesive Filtek P90, irrespective of the group. The superior bond performance for Adper Single Bond when compared to Filtek P90 adhesive was confirmed by a fewer number of adhesive failures. The influence of TAP in bond strength is insignificant.

X-tip intraosseous injection system as a primary anesthesia for irreversible pulpitis of posterior mandibular teeth: A randomized clinical trail.

BACKGROUND: Successful anesthesia during root canal therapy may be difficult to obtain. Intraosseous injection significantly improves anesthesia's success as a supplemental pulpal anesthesia, particularly in cases of irreversible pulpitis. The aim of this study was to compare the efficacy of X-tip intraosseous injection and inferior alveolar nerve (IAN) block in primary anesthesia for mandibular posterior teeth with irreversible pulpitis. MATERIALS AND METHODS: Forty emergency patients with an irreversible pulpitis of mandibular posterior teeth were randomly assigned to receive either intraosseous injection using the X-tip intraosseous injection system or IAN block as the primary injection method for pulpal anesthesia. Pulpal anesthesia was evaluated using an electric pulp tester and endo ice at 5-min intervals for 15 min. Anesthesia's success or failure rates were recorded and analyzed using SPSS version 12 statistical software. Success or failure rates were compared using a Fisher's exact test, and the time duration for the onset of anesthesia was compared using Mann-Whitney U test. P < 0.05 was considered significant. RESULTS: Intraosseous injection system resulted in successful anesthesia in 17 out of 20 patients (85%). Successful anesthesia was achieved with the IAN block in 14 out of 20 patients (70%). However, the difference (15%) was not statistically significant (P = 0.2). CONCLUSION: Considering the relatively expensive armamentarium, probability of penetrator separation, temporary tachycardia, and possibility of damage to root during drilling, the authors do not suggest intraosseous injection as a suitable primary technique.