Search

The aim of this study was to compare the effects of new irrigation solvent mixtures with Methyl ethyl ketone (MEK)/Tetrachloroethylene (TCE) and MEK/Orange oil (OOil), and different agitation techniques on dentin hardness. One hundred forty-four mandibular teeth were prepared and standardized, with each root's middle part transversely sectioned. Initial hardness was measured using a Vickers microhardness tester. Specimens were divided into four groups of agitation techniques (n = 36): no agitation; EndoActivator; IrriSafe; and XP-endo Finisher R. Each group was subdivided into six subgroups of irrigation protocols (n = 6): saline solution; NaOCl + EDTA; NaOCl + EDTA + MEK/TCE; MEK/TCE; NaOCl + EDTA + MEK/OOil; MEK/OOil. Final hardness was measured. The irrigation protocols NaOCl + EDTA, NaOCl + EDTA + MEK/TCE, and NaOCl + EDTA + MEK/OOil significantly decreased dentin hardness, while MEK/OOil increased it (p < 0.05). Comparing to NaOCl + EDTA sequence, dentin hardness increased significantly with the additional exposure to MEK/TCE (3%NaOCl + 17%EDTA + MEK/TCE) or MEK/OOil (3%NaOCl + 17%EDTA + MEK/OOil) (p < 0.05). There were no significant differences regarding agitation effects on dentin hardness decrease. The irrigation protocols affected dentin hardness significantly. However, the additional solvent proposals do not seem to address further concerns on dentin's mechanical properties. Agitation did not show any influence on dentin's hardness reduction. [ABSTRACT FROM AUTHOR]

This study evaluated changes in the root canal length (RCL) and the accuracy of the electronic apex locator (EAL) during the different stages of endodontic treatment and retreatment. Fifty-six mesial root canals of mandibular molars were selected. The actual root canal length (AL) of the canals was obtained by inserting a size 15 hand file up to the apical foramen, under magnification. The electronic lengths were obtained at the "APEX" mark of Root ZX II, using an alginate model. Both measurements were performed at three different stages of the initial root canal treatment—unflared, flared, and concluded—and at two stages of retreatment, after achieving patency and repreparation. Data were statistically analyzed and the significance level established was 5%. All stages produced a significant reduction in the AL (p < 0.05). The greatest variation was observed between the unflared–flared stages (0.2 mm) and between concluded–patency stages (0.09 mm), with no difference between them (p > 0.05). The accuracy of Root ZX II was negatively affected after achieving patency, presenting statistically significant difference compared to the other stages (p < 0.05). A significant reduction in the RCL was observed along the different stages of endodontic treatment and retreatment. The EAL was accurate to measure the root canals in most stages, except after achieving patency for endodontic retreatment. Determining and monitoring the RCL is an essential step towards a favorable prognosis, since it reduced along the different stages evaluated. Root ZX II was not accurate for endodontic retreatment. [ABSTRACT FROM AUTHOR]

This study aimed to analyse the effect of root-end resection on the sealing ability of orthograde apical plugs of three root-end filling materials (MTA Repair HP, Biodentine, MTA Plus) using the bacterial leakage method and compare it with the retrograde root-end filling technique. Eighty-four extracted mandibular premolar teeth with single root and single straight canals were selected and randomly divided into two main experimental groups (n = 36) depending on the apical plug placement technique and a control: Group I: orthograde technique, followed by root-end resection; Group II: retrograde root-end filling technique; one control Group III (n = 12): obturation with gutta-percha, followed by root-end resection. Experimental groups were further subdivided into three subgroups A, B, and C (n = 12) depending on the three different root-end filling materials used. An apical plug of 3 mm thickness was obtained in both the experimental groups. The apical sealing ability was evaluated with the dual-chamber bacterial leakage method. Statistical analysis was performed using the Kaplan–Meier survival analysis test. By the end of 30 days, the occurrence of turbidity indicating bacterial leakage was 75% in MTA Repair HP, 83.3% in Biodentine, and 91.7% in MTA Plus samples. This trend of turbidity was similar in both orthograde and retrograde technique. The control group showed turbidity in all the samples (100%). More MTA Repair HP samples (25%) survived the 30 days observation period with no bacterial leakage compared to Biodentine (16.7%) and MTA Plus (8.3%). The sealing ability of already set root-end filling materials placed through the orthograde technique did not deteriorate after root-end resection. Also among three root-end filling materials, MTA Repair HP presented the lowest bacterial microleakage followed by Biodentine and MTA Plus, respectively. [ABSTRACT FROM AUTHOR]

The aim of this study was to perform an integrative review to identify the most effective supplementary protocols used after filling material (FM) removal and root canal reinstrumentation, during endodontic reintervention. The literature search was performed on the electronic databases PubMed and Latin American and Caribbean Health Sciences Literature (LILACS), using a combination of specific scientific descriptors. Selection criteria accepted articles published in English, Spanish and Portuguese languages, up to August 2021, involving in vitro and ex vivo studies. After applying the eligibility criteria, 46 articles were included for qualitative analysis. The tool for qualitative analysis of quasi-experimental studies of the Joanna Briggs Institute was used to determine the risk of bias of the included articles. The selected articles provided important data regarding the following supplementary protocols: sonic and ultrasonic activation of the irrigating solution; the use of ultrasonic inserts, XP-endo system instruments, and photon-induced photoacoustic streaming for mechanical debridement; and new devices as GentleWave system, and the self-adjusting file. Overall, all supplementary protocols demonstrated efficacy in removing the remaining FM. The implementation of various supplementary protocols can effectively remove the remaining FM from the root canal walls, although complete removal is not always achieved. However, it was not possible to determine the most effective protocol. Conversely, their association can enhance remaining FM removal. Remaining FM attached to root canal walls hinders proper chemical–mechanical preparation during endodontic reintervention. Supplementary protocols optimize the remaining FM removal, enhancing cleaning and disinfection of root canal. [ABSTRACT FROM AUTHOR]

The aim of this systematic review and meta-analysis (SRM) was to assess postoperative pain (PP) after endodontic treatment with bioceramic root canal sealer compared to AH Plus® sealer. This SRM was carried out in accordance with the items on the PRISMA 2020 checklist and Cochrane guidelines and registered in PROSPERO (CRD42021259283). Only randomized clinical trials (RCTs) were included. Meta-analysis was conducted using R software, the standardized means difference (SMD) measure of effect was calculated for quantitative variables, and the odds ratio (OR) for binary variables. The Cochrane tool (RoB 2.0) was used to assess the risk of bias, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the quality of evidence. Qualitative and quantitative analysis included 18 and 17 studies, respectively. For quantitative variables, the bioceramic root canal sealer presented less occurrence of postoperative pain than the AH Plus® sealer in 24 h (SMD − 0.17 [− 0.34; − 0.01], p = 0.0340). For binary variables, there was no difference observed between the sealers evaluated, except for sealer extrusion where the bioceramic group had lower post-filling material extrusion (OR 0.52 [0.32; 0.84], p = 0.007). Regarding the risk of bias analysis, low risk was observed for most domains, except allocation that was considered unclear, while the certainty of evidence ranged from moderate to low. The results showed that bioceramics sealers reduced postoperative endodontic pain only after 24 h and showed less sealer extrusion compared to the AH Plus® sealer. However, more robust and standardized clinical trials are needed to confirm the results with less heterogeneity and higher quality of evidence. [ABSTRACT FROM AUTHOR]

Dental implants placed in fresh extraction alveoli provide several advantages, including shorter treatment periods and improved patient comfort. After a compromised tooth extraction, the Er,Cr:YSGG laser can considerably reduce bacterial concentration. The objective of this controlled study conducted after at least 1 year of follow-up was to compare the use of immediate post-extraction implants in infected sites treated with laser (test group) versus conventional implants in edentulous sites (control group) through an analysis of pre- and post-operative radiographs. The study was based on a series of patients treated between 2014 and 2019, with a 1-year minimum follow-up, and up to over 4 years. An analysis of the clinical history of the treated patients and pre- and post-operative radiographs was performed to evaluate the implant success and to measure the marginal bone level (MBL). Overall, 149 implants were studied. There was only one failure in the test group (1%) and no failures in the control group. The test group gained 0.1 mm of the MBL compared to the baseline, while the control group lost 0.1 mm of the MBL. The difference between the two groups of only 0.2 mm was not statistically significant (P = 0.058). Immediate dental implants in infected sockets debrided and decontaminated using Er,Cr:YSGG laser do not appear to enhance the likelihood of failure; however, peri-implantitis and associated problems must be avoided by following a certain set of protocols and procedures. [ABSTRACT FROM AUTHOR]

To investigate the efficacy of a new laser irrigation activation system [shock wave-enhanced emission photo-acoustic streaming (SWEEPS)] in terms of postoperative pain after primary root canal treatment compared with other techniques, namely photon-induced photo-acoustic streaming (PIPS), sonic system with EDDY, passive ultrasonic system (PUI), and manual dynamic activation (MDA). Two hundred patients with symptomatic irreversible pulpitis in mandibular premolar teeth were enrolled and randomly allocated to five different irrigation activation groups (n = 40) after chemo-mechanical root canal preparation. For irrigation activation, the SWEEPS and PIPS tips were attached to the Er-YAG laser system in the respective groups, while the Irrisafe tip was used in the PUI group and the EDDY tip in the sonic group. In the MDA group, irrigation was agitated with the master gutta-percha cone. At postoperative hours 8, 24, and 48 and on day 7, pain intensity was evaluated using the 10-mm Visual Analog Scale (VAS) and analgesic intake was recorded. The Kruskal–Wallis test was used to analyze the VAS scores, and pain prevalence and analgesic intake were examined with the Pearson's chi-square test at the 5% significance level. The PIPS and SWEEPS groups had the lowest level and prevalence of pain when compared to the remaining groups (P < 0.001). The PUI, sonic and MDA groups did not differ in terms of pain scores at hours 8 and 48 (P > 0.05). On day 7, the highest score and pain prevalence were recorded in the MDA group (P < 0.001). There was no difference between the groups in terms of analgesic intake (P > 0.05). Laser-activated irrigation systems provided lower postoperative pain scores and levels compared to the other activation systems. The MDA group had the highest pain scores and incidence at the end of the seventh day. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate and compare the surface deformations of different NiTi rotary files after retreatment under scanning electron microscope (SEM). A total of 240 upper central incisor teeth were obturated with vertical compaction technique and divided into 6 groups. Root canals were retreated by ProTaper Next (PTN), Twisted File Adaptive (TFA), Reciproc (RPC), ProTaper Universal Retreatment (PTR), R-Endo and Mtwo-R NiTi rotary systems. The files investigated under SEM at different magnifications and photomicrographs were captured. The photomicrographs were classified and scored. Kruskal–Wallis and Dunn tests were performed for statistical analyze at 5% significance level. PTR and RPC groups were free of defects like file separation, curving and unwinding but PTN and TFA groups showed 50% file separation. According to the photomicrographs that were captured at high magnification; there were no statistically difference between groups at the coronal thirds of the files (P > 0.05), at the middle third PTN and TFA groups showed statistically more deformation than the other groups (P < 0.05). At the apical third Reciproc was statistically showed less deformation than the other all groups (P < 0.05). Within the limitation of this in vitro study, all NiTi files showed surface deformation in SEM observation after retreatment procedures. There was less deformation in PTR and RPC groups according to other. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of several clinical factors on the success and survival rates of multiple-visit non-surgical root canal (NSRC) retreatment. Failed endodontically treated 236 teeth in 161 patients (18–72 years, 48% males; and 52% females) were retreated between March 2014 and December 2015 and were enrolled in this study. Two calibrated examiners evaluated the preoperative, intraoperative, and postoperative outcomes using the periapical index (PAI) scores. The teeth were classified as healed (healthy apical tissues, PAI ≤ 2, no signs or symptoms), healing (no signs and symptoms, PAI > 2 but reduced from the initial PAI score), and not-healed (presence of apical periodontitis, signs and/or symptoms, PAI > 2). The teeth scored as healed and healing was considered to be successful, while the not-healed ones were considered as failures. Of the 236 teeth, 135 (57.3%) in 103 patients (63.9%) were lost to follow-up, yielding to follow-up of 101 teeth (42.7%) in 58 patients (36%). Three teeth were extracted yielding to an overall success rate of 85.1%, at a mean observation time of 33.8 months. The teeth with periapical lesions < 5 mm had an 88.6% success rate, while those ≥ 5 mm had an 80% success rate (P > 0.05). While, age, gender, preoperative, intraoperative, and postoperative factors did not significantly affect the outcomes (P > 0.05), tooth type significantly affected the success rate (P < 0.05). The most frequently failed teeth were the mandibular first molars (P < 0.05). Based on these results, the multiple-visit NSRC retreatment exhibited a favorable success rate and could be offered for the endodontically failed teeth. [ABSTRACT FROM AUTHOR]

The aim was to compare the canal straightening of M-wire [Reciproc (VDW, Munich, Germany) and WaveOne (Dentsply Maillefer, Ballaigues, Switzerland)] and gold- and blue-wire heat-treated [Reciproc blue (VDW) and WaveOne Gold (Dentsply Maillefer)] instruments in severely curved root canals. A total of 80 root canals in extracted human teeth with angles of curvatures ranging between 25° and 35° and radii ranging between 3.1 and 8.5 mm were divided into four groups (n = 20). Based on radiographs taken prior to instrumentation, the groups were balanced with respect to the angle and the radius of canal curvature (P = 1.0 and P = 1.0, respectively). All canals were prepared to an apical size 25 according to the manufacturers' instructions. Pre- and post-instrumentation radiographs were superimposed and canal straightening was analysed using a computer imaging programme. Preparation time and instrument failure were also recorded. Data were analysed statistically using ANOVA and Student-Newman-Keuls test. During preparation no instrument fractured. All instruments maintained the original canal curvature well with no significant differences between the instruments (P = 0.278). Regarding preparation time, no significant differences between the four instruments were obtained (P > 0.05). Under the conditions of this study, all instruments respected the original canal curvature well. Instruments were safe to use. The use of the gold- and blue-wire heat-treated instruments was not associated with an improved shaping ability. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of different surface treatments on the flexural properties and adhesion of glass fiber post to self-adhesive luting agent and radicular dentin. Seventy-five single-rooted human teeth were prepared to receive a glass fiber post (Reblida). The posts were divided into five groups according to the surface treatment: Gr C (control; no treatment), Gr S (silanization for 60 s), Gr AP (airborne-particle abrasion), Gr HF (etching with 9 % hydrofluoric acid for 1 min), and Gr M10 (etching with CHCl for 10 min). Dual-cure self-adhesive luting agent (Rely X Unicem) was applied to each group for testing the adhesion using micropush-out test. Failure types were examined with stereomicroscope and surface morphology of the posts was characterized using a scanning electron microscopy (SEM). Flexural properties of posts were assessed using a three-point bending test. Data were analyzed using ANOVA and Tukey's HSD test. Statistical significance was set at the 0.05 probability level. Groups treated with M10 showed significantly higher bond strength than those obtained with other surface treatments ( P < 0.05). In general, improvements in bond strength (MPa) were found in the following order: M10 > C > S > AP > HF. Most failure modes were adhesive type of failures between dentin and luting agent (48.2%). SEM analysis revealed that the fiber post surfaces were modified after surface treatments. The surface treatments did not compromise the flexural properties of fiber posts. Application of M10 to the fiber post surfaces enhanced the adhesion to self-adhesive luting agent and radicular dentin. [ABSTRACT FROM AUTHOR]

This study investigated the long-term clinical outcome of root canal treatment. 240 root-treated teeth ( n = 61 patients) were initially classified on the basis of radiographic presence/absence of initial apical periodontitis (IAP) and clinical data. The final outcome measure was the periapical healing (healed/disease). The outcome at 6-9 months was correlated with the outcome at 10 years following treatment. Prognostic factors for the periapical healing were assessed. Extraction data were recorded. Univariate and multivariate logistic regression analysis was used to identify risk indicators for apical periodontitis (AP) development. Chi-square analysis was performed to evaluate a possible relationship between the 6-9 months outcome and the final outcome related to IAP. Mean observation time was 14 ± 3.7 years. Survival rate was 84.6 % and healing rate was 79 % (10-19 years). Predictors of outcome ( p < .05) were considered statistically significant. Multivariate logistic regression analysis showed that initial pulpal and periapical status and the quality of root canal filling as assessed two-dimensionally were independent predictors of outcome. The 6-9 months evaluation appears to be an indicator for the final outcome of primary root canal treatment both in the presence and in the absence of IAP. An initial radiolucency associated with an unsatisfactory quality and extent of root canal filling significantly diminishes the possibility of achieving long-term radiographic success. For those with uncertain healing at 6-9 months (91 %), clinicians should consider the high healing rate when estimating the prognosis and adjust the decision making accordingly. [ABSTRACT FROM AUTHOR]