Comparison of the dentin tubule penetration of AH Plus, WellRoot ST, and MTA BioSeal after obturation, retreatment, and re-shaping of the root canals.

It was aimed to compare the dentine tubule penetration of AH Plus, MTA Bioseal, and WellRoot ST after filling, retreating, and reshaping the root canals by using a novel microscopic method. Seventy-five mandibular incisors with single root canals were shaped with Protaper Next system (PTN; X2-25/0.06) The teeth were obturated with AH Plus labeled with Rhodamin B and MTA Bioseal or WellRoot ST sealer which were labeled with Fluo-3. Then the root canal fillings were removed with Protaper Universal Retreatment files. At the last stage, the teeth were reshaped with PTN (X3-30/0.07). The samples were transversally sectioned and examined using a Cytation 5 reader and Gen5 software regarding the mean and the maximum depth of sealer penetration. No significant difference was observed between the groups, except for the 6 mm level after reshaping the root canals (p < .05). It is not possible to completely remove the sealer remnants from the dentin walls even after reshaping the root canals. RESEARCH HIGHLIGHTS: Even after reshaping the root canals in the retreatment procedure, it is not possible to completely remove the filling residues of the epoxy-resin-based, calcium-silicate-based and MTA-based endodontic pastes from the dentin walls.

Effects of boric acid combined with injectable platelet rich fibrin on the mineralized nodule formation and the viability of human dental pulp stem cells.

BACKGROUND: The present study aimed to evaluate the viability of human dental pulp stem cells (hDPSCs) exposed to boric acid (BA) and injectable platelet-rich fibrin (I-PRF). MATERIALS AND METHODS: hDPSCs were isolated from impacted third molars. Nine milliliters of whole blood was transferred to I-PRF tubes and centrifuged at 700 rpm for 3 minutes. A BA solution was prepared by dissolving BA in a 0.1 g/ml stock solution. The cells were divided into four groups: control, I-PRF, BA, and BA + I-PRF. Cell viability was evaluated using flow cytometry. Mineralized calcium nodules were observed using Alizarin Red staining. The data were analyzed using two-way analysis of variance and Tukey's HSD test (p<0.05). RESULTS: The highest percentage of viable cells was in the I-PRF group, and the lowest percentage of viable cells was in the BA group at all times. Larger calcium nodules were observed in the BA group compared to the other groups. CONCLUSION: The use of I-PRF with or without BA had a positive effect on cell viability. BA and I-PRF affected the formation of mineralized calcium nodules. I-PRF and BA may be used in combination because these substances minimally reduce cell viability and promote mineralized nodule formation.

Effect of nanosized bioactive glass addition on some physical properties of biodentine.

The aim of this in vitro study was to investigate some physical properties of Biodentine (BD) (Septodont, France) that has been modified by adding nanosized bioactive glass (nBG) particles to it in different ratios. The cement was modified by adding 1% (7 mg) and 2% (14 mg) nBG powder to BD. BD was used as the control group in its commercial form. A total of 240 cement samples (n = 80) were prepared according to the standard measurements for each test. Subsequently, tests to determine compressive strength, microhardness, initial setting time, and solubility of the samples were performed. The obtained data were statistically analyzed using one-way ANOVA and Tukey's HDS tests, and the significance level was found to be 0.05. The compressive strength values of the samples modified with 1% and 2% nBG were higher than those of the unmodified BD; however, no statistically significant difference was found between them [BD + nBG (2 wt%) ⩾ BD+nBG (1 wt%) ⩾ control BD], (p > 0.05). The microhardness values of the samples modified with 1% and 2% nBG were found to be significantly higher than those of the control group [BD + nBG (2 wt%) > BD+nBG (1 wt%) > control BD], p < 0.05. Initial setting times were determined as 14 min for unmodified BD, 13 min for BD + nBG (1 wt%), and 12 min for BD + nBG (2 wt%). The addition of nBG to BD significantly reduced the initial setting time of BD (p < 0.05). A significant decrease was observed in the solubility of the BD modified with nBG samples compared to that of the control group [control BD > BD+nBG (1 wt%) >BD+nBG (2 wt%)], p < 0.05. Within the limitations of this study, it was found that the addition of certain amounts of nBG to BD positively affected some physical properties of the cement. Future in vitro and in vivo studies should be performed to prove the clinical applicability of the cements used in this study.

Difficulties experienced by endodontics researchers in conducting studies and writing papers.

Objectives: The study investigated the difficulties experienced by endodontics researchers around the world in conducting studies and writing papers. Materials and Methods: A survey consisting of 18 questions on the difficulties experienced by endodontics researchers in performing studies and writing papers was e-mailed to academics in the field of endodontics working at 202 universities. The independent risk factors were analyzed using binary logistic regression at a significance level of 0.05. Results: A total of 581 individuals (10.7%) agreed to participate in the study. Almost half the participants (48.2%) reported that they had received some type of training in conducting studies and writing papers. In response to the question, "Do you get help from a statistician to perform the statistical analyses of your studies?," 77.1% answered "yes." Around 40% of the participants stated that the need to obtain ethical approval negatively affected their desire to conduct studies. The participants' regions had no effect on the reported difficulties associated with writing papers in English or conducting statistical analyses (p > 0.05). Most participants (81.8%) reported difficulties in writing the Discussion section, regardless of their region, academic degrees, or years of experience. Conclusions: The participants stated they experienced difficulties in many areas, such as conducting statistical analyses, finding new ideas, and writing in English. Engaging in a detailed examination of ethics committee rules, expanding biostatistics education, increasing the number of institutions providing research funding, and increasing the number of endodontics journals can increase the enthusiasm of endodontics researchers to publish papers.

Investigation of the effect of different chelation solutions on penetration of resin-based and bioceramic sealers with a novel method.

This study aimed to investigate the effects of different chelation solutions on the penetration of resin-based and bioceramic root canal sealers into dentinal tubules using a device that assembles conventional microplate detection with automated digital microscopy. Eighty-four single-rooted teeth were prepared with 30.07 nickel-titanium instruments and divided into four groups of 21 according to the final irrigation solutions used: saline (control), ethylenediaminetetraacetic acid (EDTA), maleic acid (MA), and etidronic acid (HEBP). The samples were obturated with AH Plus, MTA Fillapex, or EndoSequence BC Sealer using the single-cone technique. The roots were then sectioned horizontally at 2, 6, and 10 mm and examined using a Cytation 5 reader and Gen5 software. Data were compared using two-way analysis of variance followed by univariate analyses and Tukey's multiple comparison test (p < .05). The mean penetration depth in the apical thirds was higher in the MA group than in the other groups (p = .013). The mean depth in the middle and coronal thirds was almost equal in the EDTA and HEBP groups. The mean depth was significantly higher in the coronal thirds of the root canals than in any other section in all final irrigation solution groups (p < .001). EndoSequence BC Sealer displayed higher penetration depth than AH Plus and MTA Fillapex, although the differences between the examined sealers were not statistically significant. The chelation solutions increased root canal sealer penetration into the dentinal tubule.

Does the Endodontic Education Level Affect Decision-Making for Endodontically Treated Teeth With Apical Periodontitis? A Web-Based Survey.

OBJECTIVES: The management of endodontically treated teeth with apical periodontitis is debated among clinicians. The aim of this study was to evaluate treatment choices for endodontically treated teeth with different sizes of periapical lesions among endodontists, endodontics postgraduate students, general dental practitioners, and undergraduate students who had fulfilled their theoretical and clinical training in endodontics. MATERIALS AND METHODS: Periapical lesion images (no periapical lesion and 1-mm, 3-mm, and 5-mm periapical lesions) were formed on 4 different radiographs with a software program, and the survey included 16 radiographs that were emailed to 1881 participants. Treatment options included extraction, surgical or nonsurgical retreatment, and wait and see. The χ2 test was used to compare the responses of the participants. RESULTS: The survey was returned by 1039 participants (55.23%). There were statistically significant differences among the responses of all participants for all cases (P < .05), except a case with a broken file and no lesion (P = .918). All participants decided to extract at an increased size from a 1-mm periapical lesion to a 5-mm periapical lesion. At all lesion sizes, general dental practitioners planned retreatment less when compared with other groups. CONCLUSIONS: This survey study showed that there was a positive correlation between endodontic education level and retreatment decision-making. Dentists who confront seemingly hopeless endodontically treated teeth such as an instrument fracture, a missing canal, or a large periapical lesion should consult with an endodontist before making the decision to extract the tooth.