Histological effects of photobiomodulation on delayed tooth replantation: a systematic review.

This systematic review evaluated preclinical studies to assess whether PBM has a more favorable histological response than other treatments used before delayed replantation of avulsed teeth. This review followed the PRISMA checklist and was registered in PROSPERO. MEDLINE (PubMed), Embase, Scopus and Web of Science were searched from their inception to July 14, 2022. Data were independently extracted by two reviewers. Data were collected about species, number of animals, number and type of teeth, groups evaluated, extra-alveolar time, parameters for PBM and other study groups, presence and characteristics of containment, observation time points, evaluation methods, characteristics evaluated, and significant results. The ARRIVE and SYRCLE tools were used to assess the methodological quality and risk of bias (RoB) of the studies. After screening, six studies were included in the review synthesis. Three of the four studies that evaluated root resorption as an outcome found that PBM decreases its occurrence after delayed tooth replantation. A meta-analysis was not conducted because some data were missing in the included studies. Half of the studies evaluating ankylosis found an increase in its occurrence after PBM. Two studies evaluated inflammatory responses and found a reduction of inflammation after PBM. In general, studies had high methodological heterogeneity, intermediate reporting quality and high RoB. Despite the methodological quality and RoB limitations of the studies, the histological responses after delayed tooth replantation were more favourable in the PBM groups. Preclinical studies supported by guidelines should define laser parameters for future clinical studies.

Cytotoxicity, biocompatibility and osteoinductive profile of an MTA-hydrogel-based cement: An in vitro and animal study.

AIM: This study aimed to evaluate the cytotoxicity, biocompatibility and osteoinductive profile of a mineral trioxide aggregate (MTA)-hydrogel-based material (MTA Flow) in comparison with MTA Angelus. METHODOLOGY: Cell viability was evaluated in human periodontal ligament stem cells (hPDLSCs) using the methyl-thiazol-tetrazolium (MTT) colourimetric assay. Polyethylene tubes containing the tested materials and empty polyethylene tubes (control) were implanted in the subcutaneous tissue of Wistar rats. Cellular (lymphocyte infiltration) and extracellular events (ECM; collagen fibres) were analysed in histological sections. Immunohistochemical (collagen I, osteopontin, bone sialoprotein, bone morphogenetic protein4) analyses were also performed. RESULTS: At 24, 48 and 72 h, all tested groups showed cell viability similar to control (p > .05). Regarding biocompatibility, all groups showed similar cellular events represented by a slight inflammatory reaction characterized by hyperaemia and a mild lymphocytic inflammatory infiltrate. The analysis of lymphocytes during the time showed a decrease in these cells in the control group and a significant interaction between MTA Angelus and control (p < .001), with MTA Angelus showing a more extensive inflammatory infiltrate. Regarding fibres, an increase in content was observed in all groups during the experimental time (7, 30 and 60 days), however, no difference was detected among the experimental groups (p = .063). After 60 days, the immunoexpression of bone matrix proteins in the MTA Flow group was similar to or higher than that observed in the MTA Angelus and in the control group. CONCLUSIONS: MTA Flow showed a non-cytotoxic behaviour, biocompatibility and ability to stimulate tissue mineralization.

Does aPDT reduce bacterial load in endodontic infected teeth? A systematic review and meta-analysis.

This systematic review investigated whether antimicrobial photodynamic therapy (aPDT) after chemomechanical root canal disinfection (CD) yields a greater microbial load reduction than only CD. An electronic literature search was conducted on four databases up to November 2022, with no language or publication date restrictions. Randomized and non-randomized clinical trials were included if participants had a primary endodontic infection in permanent teeth, and if microbial loads before and after using aPDT were compared. Two researchers independently screened titles and abstracts to determine study eligibility. Assessments included risk of bias and methodological quality. This review was registered in PROSPERO (CRD42020181783). Eight studies were included in the qualitative analysis, and six were eligible for meta-analysis. In the random effects model, aPDT significantly improved the results of root canal disinfection when compared with standard protocols for cleaning and shaping (p = 0.04, 95% CI -1.72, -0.05). Subgroup analysis suggested that aPDT has a better effect on reducing the load of anaerobic microorganisms (p = 0.003, 95% CI -3.36, -0.69). The use of aPDT as an adjunct to chemomechanical disinfection promotes additional reduction of the microbial load and, therefore, seems to improve the results of root canal treatments in permanent teeth with a primary endodontic infection. However, certainty of evidence should be improved.

Does MTA provide a more favourable histological response than other materials in the repair of furcal perforations? A systematic review.

BACKGROUND: There is no consensus on which furcal perforation repair material induces a more favourable histological response. This systematic review of laboratory studies provides an overview of the studies comparing repair materials in animal models. OBJECTIVES: To evaluate whether mineral trioxide aggregate (MTA) yields a more favourable histological response than other materials when used to repair furcal perforations in animal experimental models. METHODS: This review followed the PRISMA checklist. The studies included various materials used to repair furcal perforations and compared the histological responses with MTA. An electronic search was conducted in EMBASE, PubMed, Scopus and Web of Science up to 2 September 2020, with no language or publication date restrictions. Studies whose full text was unavailable were excluded. The ARRIVE and SYRCLE tools were used to assess the methodological quality and risk of bias (RoB) of the studies. RESULTS: The studies included in the qualitative synthesis were conducted in rat (n = 3) and dog (n = 17) models. They were classified as having a low quality, high methodological heterogeneity and high RoB. MTA and Biodentine, the materials most often compared, reduced the inflammatory reaction to mild over time. In addition, a mineralized tissue was formed in all studies. The response yielded by MTA was better than or equivalent to that of the other tested materials. DISCUSSION: This review confirmed that MTA is the reference standard material for furcal perforation repair. However, research using animal models has inherent limitations, and the substantial methodological heterogeneity across the studies included should be considered. Therefore, the knowledge generated by this systematic review should be translated into clinical practice cautiously. CONCLUSIONS: Features described in the report and quality assessment guidelines, such as PRIASE, ARRIVE and SYRCLE, should guide researchers. Despite the high RoB and the low methodological quality of the studies included, findings indicated that MTA yields a more favourable histological response than other materials in the repair of furcal perforations. REGISTRATION: PROSPERO (CRD42020181297).

Photobiomodulation therapy improves human dental pulp stem cell viability and migration in vitro associated to upregulation of histone acetylation.

This in vitro study evaluated the role of photobiomodulation therapy (PBMT) on viability and migration of human dental pulp stem cells (hDPSCs) and its association to epigenetic mechanisms such as histone acetylation. The hDPSCs were characterized and assigned into control and PBMT groups. For the PBMT, five laser irradiations at 6-h intervals were performed using a continuous-wave InGaAlP diode laser. Viability (MTT), migration (scratch), and histone acetylation H3 (H3K9ac immunofluorescence) were evaluated immediately after the last irradiation. PBMT significantly increased the viability (P = 0.004). Also, PBMT group showed significantly increased migration of cells in the wound compared to the control in 6 h (P = 0.002), 12 h (P = 0.014) and 18 h (P = 0.083) being faster than the control, which only finished the process at 24 h. PBMT induced epigenetic modifications in hDPSC due to increased histone acetylation (P = 0.001). PBMT increased viability and migration of hDPSCs, which are related with the upregulation of histone acetylation and could be considered a promising adjuvant therapy for regenerative endodontic treatment.

Antimicrobial effect of bioceramic cements on multispecies microcosm biofilm: a confocal laser microscopy study.

OBJECTIVES: To assess the viability of multispecies microcosm biofilm after contact with NeoMTA Plus, Biodentine, and MTA Angelus. MATERIALS AND METHODS: Fifty-four human dentin blocks (4 × 5 × 4 mm) were allocated to Hawley retainers, worn by six volunteers for 72 h. The blocks were then individually incubated in BHI broth for 21 days at 37 °C. At the end of experimental time for biofilm growth, the samples were randomly divided into four groups (n = 12): NeoMTA Plus, Biodentine, MTA Angelus, and negative control. The materials were placed in contact with the blocks. All samples were placed in cell-culture plate wells and incubated in BHI broth for 7 days at 37 °C. One sample from each volunteer (n = 6) was analyzed by SEM to describe the biofilm morphology. CLSM was performed to determine the percentage of viable biofilm biovolume. The data were statistically analyzed by one-way ANOVA and Tukey's multiple comparison test (α = 5%). RESULTS: SEM showed biofilm formed by spherical and rod-shaped bacteria surrounded by an extracellular matrix. No material was able to kill all biofilm cells, and all groups had more than 50% of viable bacteria. NeoMTA Plus was significantly different from the negative control group (P < .05). CONCLUSIONS: All tested materials were not effective against multispecies microcosm biofilm. CLINICAL RELEVANCE: NeoMTA Plus, Biodentine, and MTA Angelus were not effective against multispecies microcosm biofilm. It is essential to understand that these bioceramic cements are indicated for infected clinical situations. Thus, complementary disinfection procedures should be conducted prior to filling with these materials.

Efficacy of a thermally treated single file compared with rotary systems in endodontic retreatment of curved canals: a micro-CT study.

OBJECTIVES: This study aimed to compare WaveOne Gold with ProTaper and RaCe systems regarding remaining filling material, apical transportation (AT), and working time (WT) after (i) filling removal and (ii) shaping of curved canals. METHODS: Thirty mesiobuccal canals of maxillary molars were prepared and filled. After 30 days, they were randomly assigned into three groups (n = 10), according to the instruments used for filling removal and shaping, respectively: WOG-WaveOne Gold Primary and Medium; PTG-ProTaper Retreatment and ProTaper Next; RCG-D-RaCe and RaCe. Micro-CT analysis assessed the residual filling material and AT. WT was recorded. Data were statistically analyzed (α = .05). RESULTS: There was no significant difference between groups in the amount of filling material at any evaluated moment (P > .05). All groups presented low AT values. The WT was similar in all groups in filling removal (P > .05), and in shaping step WOG was faster than PTG and RCG (P < .05). CONCLUSIONS: Neither system could completely remove the filling material. The instruments evaluated were safe and the reciprocating system was faster than the rotary systems in shaping the canals. CLINICAL RELEVANCE: This study provided consistent information on filling material removal capacity of WaveOne Gold. Considering that all tested systems were safe, WaveOne Gold may be an alternative with cost-effectiveness and shorter learning curve for endodontic retreatment.

Bone tissue reaction, setting time, solubility, and pH of root repair materials.

OBJECTIVES: This study aims to compare the bone tissue reaction, setting time, solubility, and pH of NeoMTA Plus, Biodentine (BD), and MTA Angelus (MTA-A). MATERIALS AND METHODS: Initial and final setting times (n = 7) and solubility up to 7 days (n = 11) were evaluated in accordance with ASTM C266-15 and ANSI/ADA Specification No. 57, respectively. pH (n = 10) was measured up to 28 days. Bone tissue reactions in 48 rats' femur were histologically analyzed after 7, 30, and 90 days. ANOVA and Tukey's tests compared setting time, solubility, and pH data; bone reactions data were compared by Kruskal-Wallis and Dunn's tests. RESULTS: NeoMTA Plus had longer initial and final setting times than MTA-A and BD (P < 0.05). At 7 days, BD showed the highest solubility, similar to NeoMTA Plus (P > 0.05) and different from MTA-A (P < 0.05). NeoMTA Plus had a progressive mass loss over time; at 7 days, it was significantly different from the initial mass (P < 0.05). BD showed higher pH in the periods assessed when compared to the other materials (P < 0.05). Bone tissue repair had no differences between groups in each experimental period (P > 0.05). All groups presented no difference from 30 to 90 days (P > 0.05) and had better bone repair at 90 days than at 7 days (P < 0.05). CONCLUSIONS: NeoMTA Plus, BD, and MTA-A showed satisfactory setting time, high mass loss, alkaline pH, and allowed bone repair. CLINICAL RELEVANCE: Calcium silicate-based cements are indicated for multiple clinical situations. NeoMTA Plus and BD showed satisfactory physical-chemical and biological properties, being considered as alternatives to MTA-A, as root repair materials for clinical use.

External resorption of a maxillary incisor associated with a canine with a deviating eruption path: a case report.

The aim of this case report is to describe the treatment of an 11-year-old boy who was referred to an endodontist for evaluation of external inflammatory root resorption in the distal apical third of the permanent maxillary left lateral incisor, caused by deviation in the eruption path of the permanent maxillary left canine. The results of the pulpal sensitivity test of the permanent maxillary left lateral incisor were inconclusive and similar to those for the homologous tooth, so the endodontist opted for a clinical and radiographic follow-up. The patient was referred to an orthodontist, who placed a fixed Haas-type palatal expander. After the eruption of all permanent teeth, the orthodontist placed a fixed orthodontic appliance. After approximately 3 years of monitoring, bone repair with dental remodeling was observed, and the results of a pulpal sensitivity test were positive. This case demonstrates that proper monitoring is critical in establishing the diagnosis and treatment plan and ultimately to the success of clinical management.

The effect of final irrigation on the penetrability of an epoxy resin-based sealer into dentinal tubules: a confocal microscopy study.

INTRODUCTION: The aim of this study was to compare the effect of QMix, BioPure MTAD, 17 % EDTA, and saline on the penetrability of a resin-based sealer into dentinal tubules using a confocal laser scanning microscope (CLSM) and to describe the cleaning of root canal walls by SEM. METHODS: Eighty distobuccal roots from upper molars were selected and randomly divided into four groups (n = 20) before root canal preparation according to the solution used in the final rinse protocol (FRP): QG (QMix), MG (BioPure MTAD), EG (17 % EDTA), and CG (control group: saline). Ten roots of each group were prepared for SEM, and images (×2000) from the canal walls were acquired. The remaining canals were filled with a single gutta-percha cone and AH Plus with 0.1 % Rhodamine B. The specimens were horizontally sectioned at 4 mm from the apex, and the slices were analyzed in CLSM (×10). Sealer penetration was analyzed with Adobe Photoshop software. RESULTS: QG and EG presented similar amounts of sealer penetration (P > .05). MG and CG presented the lowest penetrability values (P < .05). The best results for smear layer removal of the apical third of the root canal were achieved by the QG and EG groups when compared with MG and CG (P < .05). CONCLUSIONS: Seventeen percent EDTA and QMix promoted sealer penetration superior to that achieved by BioPure MTAD and saline. CLINICAL RELEVANCE: Despite studies have not confirmed the relationship between sealing ability of endodontic sealers and their penetration in dentinal tubules, sealer penetration assumes importance, since endodontic sealers, unlike gutta-percha, are able to penetrate in dentinal tubules, isthmus, and accessory canals, filling the root canal system.

Microbial composition and diversity in intraradicular biofilm formed in situ: New concepts based on next-generation sequencing.

This study aimed to characterize the taxonomic composition of intraradicular multispecies biofilms (IMBs) formed in situ in a model to reproduce clinical conditions. Twelve palatal roots of maxillary molars had its canals prepared. Two roots were randomly selected to sterility control. Ten intraoral prosthetic appliances with lateral slots were fabricated. The roots were positioned in the slots with the canal access open to the oral cavity. Eight volunteers wore the appliance for 21 days, and two wore it at two different time points. One root from each appliance was removed and stored at -20°C until DNA extraction and sequencing (n = 10). Biofilm was analyzed using next-generation sequencing and bioinformatics. The V4 hyper-variable region of the 16SrRNA gene was amplified and sequenced. For data analyses, the mothur pipeline was used for 16SrRNA processing, and subsequent analyses of the sequence dataset were performed in R using the MicrobiomeAnalyst R package. The taxonomy-based analysis of bacterial communities identified 562 operational taxonomic units (OTUs), which belonged to 93 genera, 44 families, and 8 phyla. Bacterial colonization was different for each biofilm, and samples did not have the same group of bacteria. Alpha and beta diversity analysis revealed some general patterns of sample clustering. A core microbiome of prevalent OTUs and genera was identified. IMBs were heterogeneous when analyzed individually, but some diversity patterns were found after sample clustering. The experimental model seemed to reproduce the actual biofilm composition in endodontic infections, which suggests that it may be used to evaluate disinfection protocols.

Microbial composition and diversity in intraradicular biofilm formed in situ: New concepts based on next-generation sequencing.

This study aimed to characterize the taxonomic composition of intraradicular multispecies biofilms (IMB) formed in situ in a model to reproduce clinical conditions. Twelve palatal roots of maxillary molars had its canals prepared. Two roots were randomly selected to sterility control. Ten intraoral prosthetic appliances with lateral slots were fabricated. The roots were positioned in the slots with the canal access open to the oral cavity. Eight volunteers wore the appliance for 21 days, and two wore it at two different time points. One root from each appliance was removed and stored at -20°C until DNA extraction and sequencing (n = 10). Biofilm was analyzed using next-generation sequencing and bioinformatics. The V4 hyper-variable region of the 16SrRNA gene was amplified and sequenced. For data analyses, the mothur pipeline was used for 16SrRNA processing, and subsequent analyses of the sequence dataset were performed in R using the Microbiome Analyst R package. The taxonomy-based analysis of bacterial communities identified 562 operational taxonomic units (OTUs), which belonged to 93 genera, 44 families, and 8 phyla. Bacterial colonization was different for each biofilm, and samples did not have the same group of bacteria. Alpha and beta diversity analysis revealed some general patterns of sample clustering. A core microbiome of prevalent OTUs and genera was identified. IMBs were heterogeneous when analyzed individually, but some diversity patterns were found after sample clustering. The experimental model seemed to reproduce the actual biofilm composition in endodontic infections, which suggests that it may be used to evaluate disinfection protocols.

Effect of different disinfection protocols in bacterial viability of an intraradicular biofilm formed in situ.

The present study aimed to evaluate bacterial viability after the use of different disinfection protocols in root canals infected with a multispecies biofilm (MB) formed in situ. Palatal roots with a single canal were obtained from extracted maxillary molars and sterilized before being inserted into the mouth. The roots were contaminated with a MB in an intraoral appliance worn by ten volunteers. All volunteers wore six roots simultaneously in two intraoral devices for 21 days. One root from each volunteer was assigned to each group (n=10): PUI - passive ultrasonic irrigation; EC - Easy Clean; XPF - XP-endo Finisher; aPDT - antimicrobial photodynamic therapy; CI - conventional irrigation; and NC - negative control. The samples were evaluated under confocal laser scanning microscopy. The percentage of viable cells (VC) was calculated over the total percentage of MB biovolume. Data were statistically analyzed (α=5%). The cell viability in the entire root canal or for each third was compared between groups (Kruskal-Wallis test, Dunn post-hoc test) and for the same group (Friedman test, Dunn post-hoc test). Disinfection protocols were not significantly different from each other (P>.05). Samples in EC, PUI, and aPDT had lower cell viability than in NC (P<.05). In the coronal third of samples in the EC, XPF, PUI and aPDT, the percentage of VC biovolume was lower than in the NC (P<.05). The percentage of VC in EC samples was lower in the coronal and middle thirds than in the apical third (P<.05). EC, PUI and aPDT had significant effects on cell viability in intraradicular multispecies biofilm formed in situ when compared with untreated samples.

Impact of COVID-19 pandemic on completed treatments and referrals during urgent dental visits.

This ecological study assessed the impact of the COVID-19 pandemic on completed treatments (CTs) and referrals during urgent dental visits to primary health care units in Brazil, and their associations with socioeconomic, geodemographic, and pandemic index factors in Brazilian municipalities. The difference in rates of procedures 12 months before and during the pandemic was calculated. Data were extracted at baseline from health information systems of all municipalities that provided urgent dental care (n = 5,229 out of 5,570). Multiple logistic regression predicted the factors associated with referrals and CTs. The number of dental urgencies increased from 3,987.9 to 4,272.4 per 100,000 inhabitants. The rates of referrals decreased in 44.1% of the municipalities, while 53.9% had lower rates of CTs. Municipalities with a greater number of oral health teams in the primary health care system (OR = 1.52, 95%CI:1.21-1.91) and with specialized services (OR = 1.80, 95%CI:1.50-2.16) were more likely to decrease referrals during the pandemic. Higher HDI and GDP per capita were associated with a larger decrease in referrals and smaller decrease in CTs. The calamity generated by the long pandemic period resulted in a greater demand for urgent visits. Less developed and larger cities seem to have been more likely to not complete treatments during urgent visits in primary dental care units in times of calamity. Primary dental care offices in smaller and less developed municipalities should be better equipped to provide appropriate assistance and to improve the problem-solving capacity of dental services during emergencies.

Impact of Particle Size on the Setting Behavior of Tricalcium Silicate: A Comparative Study Using ISO 6876 Indentation Testing and Isothermal Induction Calorimetry.

This study examines the impact of particle size on the setting behavior of tricalcium silicate powders. The setting behavior was evaluated using ISO 6876 indentation testing and isothermal induction calorimetry techniques. The objective was to compare the outcomes obtained from these methods and establish a correlation between particle size and setting characteristics. The cement pastes were manually mixed with a water-to-solid ratio of 0.66 for conducting indentation tests according to ISO 6876, while calorimetry measurements were performed using isothermal (conduction) calorimetry at room temperature. The findings demonstrate a significant influence of smaller particle sizes on accelerating the hydration process of cement pastes, resulting in a reduction of setting time by up to 24%. Moreover, the final setting times obtained through the indentation method closely approximate the inflection points of the acceleration curves acquired by calorimetry, with time deviations of less than 12% regardless of particle size.

Tip and taper compatibility of accessory gutta-percha points with rotary and reciprocating instruments.

Objectives: This study was conducted to evaluate and compare the tip and taper compatibility of accessory gutta-percha points (AGPs) with various rotary and reciprocating instruments. Materials and Methods: Using a profile analyzer, tip and taper measurements were taken of 10 AGPs of each of the 14 models available from Odous de Deus and the 4 models available from Dentsply-Maillefer. Diameter measurements were taken at 1-mm intervals, from 3 mm from the tip (D3) to 16 mm. Results: Based on the mean values obtained, 3-dimensional (3D) models of the AGPs were drawn in Autodesk Fusion 360 and superimposed on 3D models of each instrument selected (Mtwo, Reciproc, RaCe, K3, and ProDesign Logic) to determine the compatibility between the instrument and the AGP. Data corresponding to the tips and tapers of the various AGPs, as well as the tip and taper differences between the AGPs and the instruments, were analyzed using descriptive statistics. The tapers of the AGPs were subject to the American National Standards Institute/American Dental Association No. 57 standard. The Odous de Deus extra-long medium and extra-long extra-medium AGPs were shown to be compatible with Mtwo, K3, and ProDesign Logic instruments with taper 0.06 and tip sizes 25 and 30, while the Dentsply fine and fine medium cones were compatible with Mtwo, RaCe, and K3 instruments with conicity of 0.04 and tip sizes 35 and 40. Conclusions: Both the Odous de Deus and Dentsply commercial brands included 2 AGP models with tip (D3) and taper compatibility with Mtwo, RaCe, K3, and/or Prodesign Logic instruments.

Apical extrusion of sodium hypochlorite in immature teeth: comparison of three different cleaning protocols.

This study compared standard needle irrigation, passive ultrasonic irrigation, XP-Endo Finisher and Easy Clean in the apical extrusion of sodium hypochlorite (NaOCl) in a model simulating immature teeth. Ten bovine teeth were maintained in suspension in a container with the apical portion in contact with 0.2% agarose gel containing 0.1% metacresol purple. The canals were irrigated with 2.5% NaOCl, according to each irrigation protocol. After 3 min, apical extrusion of NaOCl was observed by the colour gel change when in contact with NaOCl. The containers were photographed, and the NaOCl extrusion area was measured. All protocols showed NaOCl extrusion, providing similar area (P > 0.05). Considering the similarity among the studied protocols, all of them can be considered during the endodontic treatment of immature teeth. Further studies on the particularities of immature teeth should be performed to evaluate cell viability, cleaning efficiency, disinfection capacity and dentin removal promoted by the irrigation protocols.

XP Endo Finisher-R and PUI as supplementary methods to remove root filling materials from curved canals.

This study assessed the ability of XP-endo Finisher R (FKG, La Chaux-de-Fonds, Switzerland) to remove filling remnants from curved mesiobuccal canals of maxillary molars, using the passive ultrasonic irrigation (PUI) technique as a comparison. Twenty-four curved main mesiobuccal canals (MB1) of maxillary molars were instrumented with Wave One (#25/07) and filled with gutta-percha points and AH Plus Sealer. Samples were then re-treated with a standardized protocol with Wave One (#35/06) as the master apical file. Micro-CT scans measured baseline volume of remaining filling material (in mm3). Samples were divided into two groups (n = 12) according to the supplementary cleaning approach: (PUI) or XP-endo Finisher R. Statistics compared baseline and final volume of filling material (within-group); and the percentage of filling material reduction (between-group). Mean baseline volumes, final volumes, and percentages of reduction (%) of filling material for XP-endo Finisher R and PUI were respectively: 0.060 mm3, 0.042 mm3, and 31.28%; and 0.064 mm3, 0.054 mm3, and 16.57%. Both tested protocols reduced the amount of filling material (p < 0.05). XP-endo Finisher R had higher percentage of reduction as compared to PUI (p < 0.05). XP-endo Finisher R and PUI used as supplementary cleaning protocols during re-treatment improved the removal of root filling material in curved canals; but XP-endo Finisher R was approximately twice more efficient. The complete filling material removal during re-treatment procedures is still a challenge. Supplementary cleaning protocols may help to remove the remaining material after the complete mechanical preparation of curved canals. XP-endo Finisher R was approximately twice more efficient than PUI.

Evaluation of the biological and physicochemical properties of calcium silicate-based and epoxy resin-based root canal sealers.

Biocompatibility, dimensional stability, radiopacity, flow, and low solubility are the characteristics of an ideal endodontic sealer. This study evaluated and compared in vivo and in vitro biological and physicochemical properties of calcium silicate-based sealers: Sealer Plus BC (BC), MTA Fillapex (MF); and resin-based sealers: AH Plus (AHP) and Sealer Plus (SP). Apical papilla cells were exposed to sealer extracts and subjected to MTT, SRB, scratch, alkaline phosphatase enzyme activity (ALP) and Alizarin red staining (ALZ) assays. Sealers were histologically evaluated in connective tissue of Wistar rats in different periods. Radiopacity, film thickness, flow, setting time, pH and element analyses were investigated. BC had better results compared to AHP and MF at hour 72 for MTT assay (p < .05), and the highest cell viability under SRB (p < .05). All sealers presented ALP activity. BC presented the highest mineralized deposition under ALZ (p < .05). BC and MF promoted wound healing. All sealers induced an initial inflammation reaction that decreased over time. Eosinophils were observed at day 7 in MF (p < .05). Despite MF did not present final setting time, the sealers properties were in accordance to ISO 6876/2012 and ASTM C266-08. All sealers presented cell viability and biocompatibility. BC presented higher pH values and bioactivity. The materials tested showed physico-chemical properties in accordance with standards, except for MF setting time.