Search Results (239)

Background: Successful root canal treatment depends on achieving an effective three-dimensional seal and limiting microbial persistence and reinfection. Dentinal tubule penetration may enhance sealing by increasing sealer–dentin contact and micromechanical retention. This study compared the dentinal tubule penetration of BioRoot RCS, NeoSealer Flo, and TotalFill BC Sealer with AH Plus using the calcium-sensitive fluorophore Fluo-3 and evaluated the effect of sonic activation of final irrigation. Methods: 128 extracted human single-rooted teeth were allocated to four sealer groups and subdivided according to final irrigation protocol: non-activated final irrigation (NAFI) or sonic-activated final irrigation (SAFI). Sealers were labeled with 0.1% Fluo-3, and canals were obturated using the single-cone technique. Root sections obtained at 3, 5, and 8 mm from the apex were analyzed by CLSM. Penetration area and depth percentages were calculated and statistically compared (p < 0.05). Results: All sealers penetrated dentinal tubules. For overall penetration, under NAFI, BioRoot RCS and NeoSealer Flo showed significantly greater penetration area than AH Plus and TotalFill BC Sealer, while BioRoot RCS showed significantly greater penetration depth than AH Plus and TotalFill BC Sealer. Under SAFI, BioRoot RCS and NeoSealer Flo showed significantly greater penetration area than TotalFill BC Sealer, whereas NeoSealer Flo showed significantly greater penetration depth than all other sealers (p < 0.05). Sonic activation significantly increased penetration in selected sealers and root thirds; for NeoSealer Flo, penetration depth increased from 37.55% to 49.15% in the coronal third and from 33.10% to 48.73% in the middle third, while AH Plus also showed increased penetration apically and no significant effect was observed for BioRoot RCS. Penetration was generally greatest coronally and lowest apically. Conclusions: Dentinal tubule penetration was influenced by sealer type, final irrigation protocol, and root third. Sonic activation improved penetration under specific conditions but did not produce a uniform effect across all sealers or root thirds. Full article

Background: Continuous chelation with etidronic acid (1-Hydroxyethylidene-1,1-diphosphonic acid, HEDP) has been proposed as a less aggressive alternative to sequential irrigation with ethylenediaminetetraacetic acid (EDTA) in endodontics. This systematic review and meta-analysis aimed to compare the effects of these two protocols on the mechanical properties and structure of root dentin. Methods: PubMed, Scopus, and Cochrane Central databases were searched up to June 2026 for in vitro studies comparing continuous chelation (NaOCl + HEDP mixture) with sequential irrigation (NaOCl and EDTA) on root dentin of permanent teeth. Studies on coronal dentin and those not using NaOCl + HEDP as a mixture were excluded. Risk of bias was assessed using the QUIN tool. Meta-analyses were performed for fracture resistance using a random-effects model. This review was registered in PROSPERO (CRD420250630663). Results: Twenty studies with a total of 572 specimens were included. Six studies had a low risk of bias and thirteen had a medium risk. The qualitative synthesis showed that HEDP generally resulted in similar or lower levels of erosion, microhardness reduction, demineralization, and collagen degradation compared to EDTA. The meta-analysis revealed no significant difference in fracture resistance (5 studies; SMD = 0.28; 95% CI: −0.37 to 0.92; p = 0.40); however, substantial heterogeneity was observed (I² = 66.7%). Conclusions: The evidence was limited by substantial heterogeneity and mainly medium risk of bias. Within the limitations, in vitro evidence suggests that continuous chelation with HEDP is comparable to EDTA in terms of root dentin mechanical properties and composition, supporting its use as a chelating agent in endodontic practice. This research received no external funding. Full article

Bioceramic sealers have gained widespread acceptance in contemporary endodontics due to their favorable biological properties, dimensional stability, and bioactivity. However, their strong adhesion to dentinal walls and penetration into dentinal tubules may complicate removal during endodontic retreatment procedures. Additionally, the obturation technique may influence both the retreatability of root canal filling materials and the bond strength of sealers and resins to radicular dentin. Methods: One hundred extracted human single-rooted teeth were instrumented using the WaveOne Gold system and obturated with a bioceramic sealer using two techniques: single-cone (Group A, n = 50) and warm vertical compaction (Group B, n = 50). After sealer setting, retreatment procedures were performed using ProTaper Universal Retreatment files combined with passive ultrasonic irrigation. Scanning electron microscopy was used to evaluate smear layer removal and dentinal tubule obstruction. Eighty specimens were subsequently re-obturated with a bioceramic sealer and divided into four subgroups according to the obturation technique used before and after retreatment. A push-out bond strength test was performed on coronal, middle, and apical root sections. Statistical analysis was conducted using SPSS software with a significance level set at p ≤ 0.05. Results: No statistically significant differences were observed between the groups regarding the working time required for root filling removal (p > 0.05). However, significant differences were found in push-out bond strength values among the experimental groups (p < 0.05). Specimens obturated using warm vertical compaction showed significantly higher bond strength compared with the single-cone technique. Scanning electron microscopy observations revealed less residual bioceramic sealer on dentinal walls in the warm vertical compaction group. Conclusions: Within the limitations of this in vitro study, the warm vertical compaction technique demonstrated superior bonding performance and resulted in less residual bioceramic sealer after retreatment compared with the single-cone technique. Full article

Endodontic irrigant solutions act as crucial pretreatment conditioning agents in dentin biomimetic remineralization, preparing the collagen scaffold for calcium phosphate infiltration and subsequent tooth structure reconstruction. In this study, root dentin discs were exposed for 10 min to five irrigant solutions: sodium hypochlorite (NaClO, 3%), EDTA (17%), citric acid (CA, 10%), chlorhexidine (CHX, 2%), and an innovative experimental formulation containing citric acid (7%) and surfactants. Samples were then aged in Hank’s Balanced Salt Solution (HBSS) at 37 °C for three months to simulate long-term clinical conditions. Physicochemical modifications of the collagen and apatite phases were assessed at each experimental stage using ATR-FTIR spectroscopy, with the A_CaP/A_{Amide I} and A₈₇₀/A_CaP absorbance ratios as markers of the degree of mineralization and apatite carbonate content, respectively. Results indicated that CHX- and EDTA-treated dentin exhibited the highest remineralization after ageing, while NaClO impeded remineralization due to collagen degradation. The experimental irrigant produced the most pronounced demineralization, followed by CA; however, it also facilitated significant remineralization, attributed to citrate–collagen binding and surfactant-enhanced apatite nucleation. NaClO selectively degraded collagen and increased apatite crystallinity; CA inhibited apatite nucleation through adsorbed citrate ions, and CHX and EDTA induced minimal alterations. These findings provide molecular-level evidence linking short-term irrigant effects to the long-term potential for dentin biomineralization, with direct implications for irrigant selection in regenerative endodontic protocols. It should be noted that this study was conducted on dentin discs obtained from a single tooth; all findings should therefore be regarded as preliminary and require confirmation in studies with larger, biologically independent sample sizes. Full article

Sodium hypochlorite (NaOCl), as the most commonly used irrigant solution, offers strong antibacterial and organic tissue dissolving properties and has the potential to express a strong corrosive effect. The aim of the study was to evaluate the effects of NaOCl on corrosion behavior and cyclic fatigue in five different types of NiTi rotary endodontic instruments. The study examined: ProTaper Universal, ProTaper Next, Twisted File, HyFlex CM, and BioRace, each with 24 samples. Each group was divided into a control subgroup and a subgroup exposed to electrochemical testing of corrosion in 5.25% NaOCl. All instruments were exposed to a cyclic fatigue test in artificial canals with a curvature angle of 60 degrees and radius of 2 mm. The corrosion potential of NaOCl was determined in all groups of instruments. ProTaper Universal had a significantly lower corrosion resistance than ProTaper Next (p < 0.05), Twisted File, BioRace, and HyFlex CM (p < 0.001). HyFlex CM showed significantly higher resistance to cyclic fatigue compared to all the other groups of instruments (p < 0.001). Surface corrosion reduced cyclic fatigue resistance in most of the instrument groups, except in heat-treated instruments with controlled memory. HyFlex CM has proven to have the highest resistance to corrosion and cyclic fatigue. Full article

Odontogenic cutaneous sinus tracts represent an uncommon clinical manifestation of chronic dental infection and are frequently misdiagnosed due to the absence of dental symptoms and their resemblance to dermatologic lesions. This case report describes the nonsurgical endodontic management of a cutaneous sinus tract of dental origin in a 13-year-old patient. The patient presented with a persistent extraoral lesion in the mandibular region, initially evaluated by non-dental specialists. Clinical and radiographic examination revealed a necrotic mandibular first molar associated with a periapical radiolucency and intraoral sinus tract. Nonsurgical root canal treatment was performed using chemomechanical debridement with sodium hypochlorite irrigation and calcium hydroxide as an intracanal medicament. Complete obturation was achieved following resolution of intracanal exudation. No surgical intervention of the cutaneous lesion was undertaken. Progressive healing of the periapical lesion and spontaneous resolution of the extraoral sinus tract were observed over a 6-month follow-up period. This case is noteworthy because it combines a prolonged diagnostic delay, an atypical extraoral manifestation in a child, and successful resolution by nonsurgical endodontic therapy alone without surgical excision of the cutaneous lesion. The 6-month follow-up confirms sustained clinical and radiographic healing, underscoring the importance of early recognition and conservative management in pediatric patients. Early identification and elimination of the dental source can prevent unnecessary surgical procedures and minimize the risk of permanent scarring. Full article

Sodium hypochlorite (NaOCl) remains the gold standard irrigant in endodontics due to its proteolytic and antimicrobial properties, whereas hydrogen peroxide (HP) is widely used for internal bleaching because of its oxidative capacity. Both agents have been associated with chemical and structural alterations in dentin; however, the impact of their sequential application on the organic–mineral balance has not been fully elucidated. Objective: To evaluate whether the isolated and sequential application of 5.25% NaOCl and 37.5% HP induces chemical alterations in dentin by analyzing changes in the organic matrix and mineral phase using Fourier-transform infrared spectroscopy (FTIR) and Energy-dispersive X-ray spectroscopy (EDX). Methods: Twenty-four independent dentin sections (n = 6 per group) from six human third molars were distributed using a tooth-balanced allocation into four groups: Control, NaOCl (5.25%, 15 min), HP (37.5%, 30 min), and sequential NaOCl+HP. FTIR assessed organic (amide I, II, III, CH₂) and inorganic (phosphate, carbonate) components through baseline-corrected integrated areas, Full Width at Half Maximum (FWHM), and molecular ratios. Surface elemental composition and the calculated Ca/P atomic ratio were determined by EDX. Multiple sub-measurements per specimen were averaged before statistical analysis. Data were analyzed using Kruskal–Wallis and Mann–Whitney U tests with Bonferroni correction (p < 0.05). Results: FTIR revealed treatment-dependent modifications. NaOCl reduced absorbance in organic-associated bands, indicating collagen degradation, whereas HP altered the mineral phase. The NaOCl+HP group exhibited increased numerical values for integrated band areas, with differences detected in carbonate, phosphate, and amide III bands (p < 0.05), reflecting structural disorganization and modified spectral signal rather than tissue preservation. No differences were detected across the calculated infrared ratios (p > 0.05). EDX showed decreased absolute atomic percentages of Ca, P, and O in the NaOCl+HP group (p < 0.05), indicating structural demineralization, while its stoichiometric Ca/P ratio remained at 1.56. Isolated HP shifted the mineral stoichiometry to the highest numerical Ca/P ratio (1.69; range 1.58–1.80). Fluorine decreased across all treated groups (p < 0.001). Conclusions: Sequential NaOCl and HP application triggers distinct chemical alterations compared to individual treatments, inducing severe structural disorganization of the organic network and absolute mineral depletion of Ca and P. This multi-agent sequence alters dentin stoichiometry, which may compromise the biomechanical integrity of the tissue. Full article

The aim of this systematic review was to assess the influence of different final irrigation protocols and activation methods on the dentinal tubular penetration of calcium silicate-based sealers (CSSs). The review followed the PRISMA 2020 guidelines, and the protocol was registered in the Open Science Framework (OSF; DOI: 10.17605/OSF.IO/5HTVN). A PICOS-based research question was formulated, and a comprehensive literature search was conducted in MEDLINE, Scopus, Embase, Web of Science, and SciELO up to October 2025. After study selection, a qualitative synthesis of methodologies and outcomes was performed, and methodological quality was assessed using the QUIN tool. Twenty-one in vitro studies were included, all of which used single-rooted teeth or single roots. The available evidence suggests that final irrigation protocols may influence CSS penetration, although the magnitude and consistency of this effect varied substantially across studies. Sodium hypochlorite (NaOCl) and 17% EDTA were the most frequently investigated irrigants and were generally associated with improved penetration, but no irrigation protocol or activation technique can currently be considered superior. Current research trends include the evaluation of chelating agents, continuous chelation protocols, and irrigant activation systems such as passive ultrasonic irrigation, sonic activation, laser activation, and XP-Endo Finisher. Future studies should standardize irrigation protocols, activation methods, sealer types, obturation techniques, microscopy-based assessment procedures, and penetration outcome measures, while also including larger samples and more anatomically complex root canal systems. Full article

Background/Objectives: The aim of this study was to compare the effectiveness of the Reciproc Blue (RB) and MicroMega Remover (MR) systems in removing root canal filling material and to evaluate the effect of passive ultrasonic irrigation (PUI) on remaining filling material (RFM) using micro-computed tomography (micro-CT)-based three-dimensional (3D) analysis. Methods: Forty single-rooted mandibular premolar teeth were included in the study. The root canals were prepared up to size F2 using the ProTaper Gold rotary file system and obturated with the lateral compaction technique. After the initial micro-CT scan, the teeth were randomly divided into four groups: Group RB, Group MR, Group RB + PUI, and Group MR + PUI (n = 10). Following retreatment, a second micro-CT scan was performed. The percentage of RFM was calculated, and statistical analyses were performed using Kruskal–Wallis and Mann–Whitney U tests with Bonferroni correction. A rank-based factorial analysis was additionally performed (p < 0.05). Results: RFM was observed in all groups. No significant difference was found between the RB (7.37%) and MR (7.31%) systems (p > 0.05). However, the groups treated with PUI (RB + PUI and MR + PUI) showed significantly lower RFM values than the groups without PUI (p = 0.001). Factorial analysis revealed no significant effect of file system or file system × PUI interaction, whereas PUI significantly reduced RFM (p < 0.001). Conclusions: The RB and MR systems demonstrated similar effectiveness in removing root canal filling material. Although complete canal cleanliness could not be achieved, under the in vitro conditions of the present study, PUI significantly reduced the amount of micro-CT-measured RFM. Full article

Background: The objective was to synthesize and critically appraise systematic reviews with meta-analysis evaluating the association between irrigation, instrumentation, and obturation procedures and post-operative endodontic pain. Methods: An umbrella review was conducted following PRISMA guidelines. Electronic searches identified systematic reviews published between 2016 and 2025. Eligible studies are systematic reviews that include meta-analyses, published in English and correlating the presence of post-operative pain in 3 different critical stages of root canal treatments, namely irrigation, instrumentation and obturation. Methodological quality was assessed using the AMSTAR 2 tool. Outcomes included pain prevalence and intensity at different time points. Results: Out of 368 records, 25 systematic reviews with meta-analysis met the inclusion criteria: 9 on irrigation, 8 on instrumentation, and 8 on obturation. NaOCl concentrations, irrigant activation, and intracanal cryotherapy were repeatedly reported as being associated with reduced short-term post-operative pain. For instrumentation, most reviews reported lower pain with rotary systems, but two studies found no difference or favored reciprocating kinematics. Apical patency did not appear to increase pain and foraminal enlargement may increase early pain. No clinically consistent differences were observed between bioceramic/calcium silicate-based and resin-based sealers, although calcium silicate sealers seem to support periapical healing. However, the certainty of these findings was limited by heterogeneity, methodological weaknesses, and overlap among primary studies. Methodological limitations were identified across reviews, mainly related to no protocol registration (n = 4), incomplete reporting of excluded studies with justification (n = 11), limited assessment of publication bias, and poor reporting of funding sources for primary studies. Conclusions: Based on current evidence, irrigation, instrumentation, and obturation procedures may influence short-term post-operative pain. However, these findings remain tentative because of heterogeneity, methodological weaknesses, variable review quality, and overlap among primary studies. Further high-quality reviews and clinical trials are needed. Full article

Apical periodontitis is a common inflammatory oral condition and a major cause of endodontic treatment need. The present retrospective clinical study aimed to evaluate the frequency, distribution, and radiographic healing of teeth diagnosed with apical periodontitis following primary endodontic treatment or nonsurgical retreatment within a specific patient cohort. Consecutive patients presenting for endodontic treatment at the study clinic between 2020 and 2021 were screened for inclusion. Eligible cases were those in which patients provided written informed consent, presented with periapical inflammatory pathology, and underwent conservative endodontic treatment. Exclusion criteria were incomplete data, non-functional or non-restorable teeth, third molars, pregnancy, probing depth ≥ 4 mm, radiographic bone loss, pathologic tooth mobility due to attachment loss, periodontal involvement of the lesion, and primary dentition. A total of 277 teeth, all diagnosed with apical periodontitis at baseline, were included. Some patients contributed more than one tooth. All treatments were performed by a single operator according to a standardized clinical protocol, including uniform diagnostic criteria, chemo-mechanical preparation, irrigation regimen, obturation technique, and radiographic follow-up at 12 and 24 months. Periapical healing was assessed radiographically using the Periapical Index (PAI). Within this cohort, elderly patients significantly represented the largest proportion of those treated (p < 0.001). Maxillary teeth also comprised a significantly higher proportion of cases than mandibular teeth (55.2% vs. 44.8%). The mean initial PAI score was 3.37 ± 0.9 points, with a median of 3 points, and the final score was 1.31 ± 0.93 points, with a median of 1 point. Radiographic healing was observed in 56.68% of cases at 12 months and in 84.84% of cases at 24 months. Primary endodontic treatment and nonsurgical retreatment of teeth with apical periodontitis in this selected patient population were associated with substantial radiographic improvement over a 24-month follow-up period. These findings support the value of standardized endodontic management and longitudinal radiographic monitoring. Full article

Background: The biological response of the periodontal ligament (PDL) following endodontic treatment remains insufficiently investigated. This systematic review aimed to evaluate the influence of endodontic treatment modalities on PDL-related healing outcomes and periapical tissue repair. Methods: A systematic review was conducted according to PRISMA 2020 guidelines. PubMed, Scopus, Web of Science, and the Cochrane Library were searched for randomized clinical trials published between 2015 and 2025. Studies evaluating the effects of endodontic interventions on clinical, radiographic, or biological outcomes associated with PDL healing. Risk of bias was assessed using the Cochrane RoB 2 tool. Results: Ten randomized clinical trials involving approximately 710 participants were included. Endodontic treatment was generally associated with favorable healing outcomes, reflected by reductions in periapical lesion size, improvement of radiographic parameters, and resolution of clinical symptoms. Single-visit and multiple-visit treatments demonstrated comparable long-term healing outcomes, although single-visit protocols were associated with increased short-term postoperative discomfort. Activated irrigation techniques appeared to enhance healing compared with conventional irrigation methods. Most studies were judged as having some concerns regarding risk of bias. Conclusions: Current evidence suggests that endodontic treatment can promote favorable healing of the periodontal ligament–periapical complex through effective infection control and resolution of inflammation. However, the certainty of evidence remains moderate because of methodological heterogeneity and the limited availability of studies directly assessing biological PDL outcomes. Further well-designed randomized clinical trials with standardized outcome measures and longer follow-up periods are required. Full article

Dentin deproteinization strategies are being revisited as adjunctive approaches to reduce technique sensitivity, improve monomer infiltration to mineralized dentin, and enhance the longevity of resin–dentin interfaces. This organized narrative review critically summarizes the chemistry, kinetics, biological considerations, and clinical translatability of agents used for smear-layer deproteinization or post-etching deproteinization. Searches of PubMed/MEDLINE, Scopus, and LILACS up to October 2025 were used to identify evidence on oxidizing irrigants (sodium hypochlorite/hypochlorous acid, calcium hypochlorite, peracetic acid, chlorine dioxide), enzymatic proteolysis treatments (bromelain, papain, trypsin/pepsin, and GAG-targeting enzymes), physical approaches (heat and lasers), and post-oxidizer reducing/antioxidant strategies. Oxidizers provide the fastest and most surface-verified organic removal, but their clinical value is limited by concentration- and time-dependent oxidative carry-over, which interferes with free-radical polymerization. Enzymes offer a more selective route, although their support is driven largely by bond strength and morphological outcomes rather than direct surface-chemical confirmation. Heat remains a proof-of-principle method rather than a clinical option, whereas laser protocols are highly parameter-sensitive. Overall, deproteinization should be interpreted through a combined framework of surface chemistry, adhesive compatibility, aging behavior, biosafety, and chairside feasibility. Current evidence supports cautious, protocol-specific development rather than routine clinical adoption, with priority given to clinically realistic time-dose windows and paired surface/aging outcomes. Full article

Root canal disinfection remains challenging due to anatomical complexity and the limitations of mechanical instrumentation. Evidence on irrigation is often fragmented and focused on isolated outcomes, limiting clinically integrated protocols. This narrative review provides a clinically oriented interpretation of contemporary irrigation and activation strategies, introducing a substrate-centered perspective emphasizing dentin modification and material interaction. A structured narrative search was conducted in PubMed, Scopus, and Web of Science up to February 2026 using keywords related to irrigants, irrigation protocols, activation techniques, and dentin–material interactions. Studies were selected based on clinical relevance, including complex anatomy, mature biofilms, and realistic irrigation sequences. Irrigation effectiveness is determined by the interplay between irrigant chemistry, fluid dynamics, and activation-mediated distribution within the root canal system, as well as by irrigation-induced dentin modifications influencing the dentin–material interface. Sodium hypochlorite and chelating agents remain central, although their performance depends on delivery and activation. Activation enhances irrigant exchange, biofilm disruption, and penetration into complex regions. Irrigation also induces physicochemical changes in dentin, affecting sealer penetration and interfacial stability. It should not only be considered a disinfection step but also a substrate-conditioning phase linking cleaning to obturation, with implications for treatment predictability and long-term outcomes. Full article

Background/Objectives: Effective irrigation of the apical third remains one of the greatest challenges in root canal treatment, particularly in curved canals where anatomical complexity restricts irrigant penetration. This in vitro study evaluated the irrigation efficacy of four syringe-needle designs under standardized conditions. Methods: Ten transparent resin blocks with approximately 30° curved canals were instrumented to size 30/0.04 taper. Four irrigation needle designs were tested: flat open-ended (27G), notched open-ended (27G), double-vented closed-ended (27G), and finally a flexible polypropylene closed-ended (IrriFlex, 30G) used as a reference. Canals were filled with methylene blue and irrigated dynamically with distilled water. Residual dye was quantified spectrophotometrically at 665–668 nm. Data were analyzed using ANOVA with post hoc testing (p < 0.05). Results: Significant differences were found among the needle designs. The flexible polypropylene needle showed the lowest absorbance values and performed significantly better than both the flat open-ended and double-vented metallic needles. The notched open-ended needle demonstrated irrigation efficacy comparable to the flexible needle. The double-vented metallic needle exhibited the highest residual dye levels, indicating the poorest irrigation performance. Conclusions: Needle design significantly influences irrigation efficacy in curved root canals. Flexible and notched designs enhanced apical dye removal compared with conventional metallic open-ended and side-vented needles. Differences in performance appear to be governed by a combination of vent configuration, needle flexibility, penetration depth, and fluid-dynamic behavior rather than needle gauge alone. Full article