Dentsply Tulsa Dental Specialties Research Articles

Standardization of Variable Taper Files and Corresponding Gutta-Percha Cones Amongst Manufacturers

IntroductionCurrently there is no standardization of variable taper endodontic files and corresponding gutta-percha (GP) cones. The aim of this study was to evaluate intramanufacturer and intermanufacturer variability of diameter and taper in the apical third of GP master cones and finishing files from 3 commercially available variable taper endodontic systems. MethodsDiameter measurements were recorded using digital microscopy at 1-mm increments (D1-D4) for F2 files and corresponding GP cones (n = 20 per system) from ProTaper Gold (Dentsply Tulsa Dental Specialties, Johnson City, TN), EdgeTaper Platinum (EdgeEndo, Albuquerque, NM), and ExactTaper H (SS White, Lakewood, NJ). Taper was defined as the rate of change in diameter per 1-mm increment. Mean differences in diameter were assessed using repeated measures of analysis of variance for D1 to D4 and the Wilks test for differences in taper. ResultsIn the apical third, ProTaper and EdgeEndo mean file diameters were significantly smaller than corresponding GP cone diameters (P < .01, P < .01, respectively). Contrastingly, SS White file diameters were significantly larger than their corresponding GP cones (P = .02). Files from all manufacturers had significantly smaller diameters than advertised (nominal) values (P < .01). ProTaper GP cones had similar diameters to nominal values (P = .30), while EdgeEndo and SS White GP cones were significantly smaller (P < .01). Amongst files and corresponding GP cones from all systems, taper was nonstandardized. ConclusionsSize discrepancies between finishing files and corresponding GP cones can be expected amongst variable taper endodontic systems. Therefore, clinicians should be prepared to make intraoperative adjustments when obturating.

A Comparative Evaluation of Contact Angle and Depth of Penetration of Sodium Hypochlorite With Various Surfactants: An In Vitro Study.

Sodium hypochlorite (NaOCl) is regarded as the most frequently used root canal irrigant. Its high surface tension prevents its penetration into complex canal anatomies. The present study assesses the contact angle and penetration depth of 2.5% NaOCl with 0.2% cetrimide and propylene glycol. Sixty recently extractedmandibular premolars with a single root were obtained. Thirty were sectioned longitudinally, and the remaining 30 teeth were sectioned transversely. Acrylic blocks were used to mount the parts, and 5 µL of each of the following solutions was placed on the dentin surface: Group 1: 2.5% NaOCl (control), Group 2: 0.2% cetrimide + 2.5% NaOCl, and Group 3: propylene glycol + 2.5% NaOCl. Following this, contact angle analysis was made using a contact angle goniometer. We prepared and instrumented access cavities in 30 teeth to work up to the size of the ProTaper Gold F2 (Dentsply Tulsa Dental Specialties, Tulsa, OK). Samples were allocated to the three groups, and irrigation was done accordingly. They were sectioned at the coronal, middle, and apical thirds and then subjected to confocal laser scanning microscopy. The data were analyzed using a one-way ANOVA and a Tukey multiple comparison test. Group 2 had the least contact angle (35.20°) and the highest depth of penetration (DOP; 752.409 µm) when compared to Groups 1 and 3. The DOP decreased significantly from the coronal, middle, and apical thirds. No discernible variation in the contact angle was found between the radicular and coronal portions. 0.2% cetrimide improved the efficiency of 2.5% NaOCl as an irrigant by lowering its contact angle and increasing its DOP.

Incidence of Postoperative Pain after Single Visit Root Canal Treatment using XP-endo Shaper, 2Shape and ProTaper Gold Rotary Systems: A Prospective Randomized Clinical Trial.

To evaluate the incidence of postoperative pain, treatment time and analgesic intake after single visit endodontic treatment of mandibular molars using XP-endo Shaper, 2Shape and ProTaper Gold rotary systems. 150 patients with irreversible pulpitis were scheduled for single visit root canal treatment. Teeth were randomly assigned to one of the three groups: ProTaper Gold (PTG; Dentsply Tulsa Dental Specialties, Johnson City, TN), 2Shape (2S; Micro-Mega, Besancon, Cedex, France) and XP-endo Shaper (XPES; FKG Dentaire, La Chaux-de-Fonds, Switzerland). Preoperative and postoperative pain was rated by the patients at the beginning of treatment and after 24, 48, 72 hours and 7 days on Heft Parker's visual analog scale (HP-VAS). Highest mean postoperative pain score was recorded in PTG (P<0.05), followed by 2S and XPES respectively at all time intervals. XPES exhibited maximum reduction from preoperative pain at 24 (48.67%) and 48 hours (96.90 %) with no pain at 72 hours. Treatment time was significantly least in XPES (P<0.05) followed by 2S and PTG; but no significant difference in analgesic intake was noted. XPES exhibited least postoperative pain at all time intervals and treatment time, followed by 2S and PTG rotary systems respectively. (EEJ-2022-04-053).

ROOT СOVERAGE IN GINGIVAL RECESSION AND CORRECTION OF INSUFFICIENTLY ATTACHED GINGIVA USING OF PERIODERM ™: CASE SERIES REPORTS

Gingival recessions are one of the most common aesthetic and functional periodontal problems, but also one of the most difficult in terms of etiology and treatment. Various surgical treatments for this condition have been described in the literature. Root closure for gingival recession using PerioDerm is one such method that has shown promising results. The purpose of this case series reports is to demonstrate the benefits of PerioDerm™ Acellular Dermis (DENTSPLY Tulsa Dental Specialties; Tulsa, Oklahoma) in reducing recession and adding connective tissue during periodontal-restorative complex treatment.The use of PerioDerm has shown positive results and has shown itself as a viable option for closing roots during a recession.

Healing Assessment of Osseous Defects after Surgical Removal of Periapical Lesions in the Presence of Hydroxyapatite, Nanohydroxyapatite, and a Combination of Nanohydroxyapatite and Platelet-rich Fibrin: A Clinical Study

Abstract: Aim: to evaluate the bone healing in failed endodontically treated teeth after surgical removal of periapical lesions and placement of hydroxyapatite (HA), nanohydroxyapatite (nHA) and a combination of nanohydroxyapatite with platelet rich fibrin (PRF) periapically. Subjects and methods: the study was conducted on twenty-four patients having periapical radiolucency in single rooted teeth. The selected teeth were divided into three groups: Group A, Group B, and Group C; of 8 teeth each. All the teeth were retreated in two visits. In the first visit the old filling was removed using Protaper retreatment files (Dentsply Sirona®) then irrigation with sodium hypochlorite 2.5% was done. All canals were dried and filled with Di-antibiotic paste (metronidazole and ciprofloxacin). In the second visit the canals were obturated with Pro Taper gutta-percha points and root canal sealer (Adseal resin sealer) followed by surgical intervention in the same day. A periapical curettage along with apicoectomy were established. In all the groups, root end cavity was prepared and filled with MTA (ProRoot MTA; DENTSPLY Tulsa Dental Specialties). In Group A, hydroxyapatite powder was packed in the curetted periapical defect. In Group B, nanohydroxyapatite powder was packed in the curetted periapical defect. In Group C, nanohydroxyapatite with PRF were mixed and packed in the curetted periapical defect. In all groups, patients recall visits were scheduled at 1, 3, and 6 months’ time intervals for clinical and radiological evaluation. Results: after one month; there was a statistically significant difference between the median percentage changes in lesions size in the three groups. Pair-wise comparisons between groups revealed that there was no statistically significant difference between group B (nHA) and group C (PRF and nHA) groups. Both showed statistically significantly higher median percentage reduction in lesions size than group A (HA group). After three as well as six months; there was no statistically significant difference between the median percentage decreases in lesions size in the three groups. Conclusion: It was concluded that nHA combination with PRF produced faster periapical healing (bone regeneration) in the first three months than nHA alone. However, HA produce periapical healing (bone regeneration) after six months.

Visualization of bubbles generation of electrical-driven EndoActivator tips during solutions activation in a root canal model and a modified extracted tooth: A pilot study

Background: EndoActivator, a sonically-driven canal irrigation system (Dentsply Tulsa Dental Specialties, Tulsa, OK), has been developed for activating root canal irrigants, and has recently been released onto the market. Purpose: To obtain an initial understanding of bubbles generation of electrical EndoActivator tips during activation of the irrigant in a transparent root canal model and a modified extracted tooth. Methods: A modified extracted tooth and a straight glass model were filled with a solution containing 17% EDTA or 3% NaOCl. A medium activator tip 22-mm polymer noncutting #25, 0.04 file driven by an electrical sonic hand-piece at 190 Hz (highest level) induced pressure waves that produced macro- and micro-bubbles. The physical mechanisms involved were visualized using a Miro 320S high-speed imaging system (Phantom, Wayne, NJ, USA) with high temporal and spatial resolutions. The imaging system acquired images at 25,000 frames per second with 320×x240 pixels per image, and attached a 60-mm f/2.8 macro lens (Nikon, Tokyo, Japan). Results: The end of the tip did not generate bubbles formation. Disruption of surface tension at the air–solution system in the glass canal model by an electrical sonic driven EndoActivator tip generated bubbles in the solution. However, it did not occur at the system of solution–air interfaces in the glass canal and modified extracted tooth. Conclusion: The physical mechanism of the solution activated by an electrical sonic driven EndoActivator tip in generting bubbles formation is because the surface tension at the air–solution system disruption. No bubbles formation occurred in the solution in the restricted space either in the solution-air system or modified extracted tooth. Better understanding of the physical mechanisms that relate specifically to the activation behaviour of EndoActivator tips in solutions is key to improving the cleaning mechanism that applies during root canal treatment.

Biological Characteristics and Odontogenic Differentiation Effects of Calcium Silicate-Based Pulp Capping Materials.

We compared calcium silicate-based pulp capping materials to conventional calcium hydroxide in terms of their biological properties and potential effects on odontogenic differentiation in human dental pulp stem cells (hDPSCs). We cultured hDPSCs on disks (7-mm diameter, 4-mm high) of ProRoot MTA (Dentsply Tulsa Dental Specialties), Biodentine (Septodont), TheraCal LC (Bisco), or Dycal (Dentsply Tulsa Dental Specialties). Cell viability was assessed with cell counting (CCK) and scanning electron microscopy (SEM). Odontogenic activity was assessed by measuring alkaline phosphatase (ALP) activity and gene expression (quantitative real-time PCR). CCK assays showed that Dycal reduced cell viability compared to the other materials (p < 0.05). SEM showed low and absent cell attachment on TheraCal LC and Dycal disks, respectively. hDPSCs exposed to TheraCal LC and Dycal showed higher ALP activity on day 6 than the control group (p < 0.05). The day-9 Runx2 expression was higher in the ProRoot MTA and TheraCal LC groups than in the control group (p < 0.05). On day 14, the ProRoot MTA group showed the highest dentin sialophosphoprotein levels (not significant; p > 0.05). In conclusion, various pulp capping materials, except Dycal, exhibited biological properties favorable to hDPSC viability. ProRoot MTA and TheraCal LC promoted higher Runx2 expression than Biodentine. Future studies should explore the odontogenic potential of pulp capping materials.

Mineral trioxide aggregate

The purpose of this two-part series is to review the composition, properties, products, and clinical aspects of mineral trioxide aggregate (MTA) materials.search engines to include relevant scientific citations from the peer-reviewed journals published in English. MTA is a refined form of the parent compound, Portland cement (PC). It demonstrates a strong biocompatible nature owing to the high pH and its ability to form hydroxyapatite. MTA materials provide a better seal than traditional endodontic materials as observed in dye leakage, fluid filtration, protein leakage, and bacterial penetration leakage studies, and it has been recognized as a bioactive material. Currently a variety of MTA commercial products are available, including Proroot® Gray MTA and White MTA both from DENTSPLY Tulsa Dental Specialties , and MTA Angelus Although these materials are indicated for various dental uses. This first of this series highlights and discusses the composition, physical, and/or chemical properties of MTA. A subsequent article will offer an overview of the material aspect (commercial products) and clinical considerations for MTA materials.

Influence of Progressive Versus Minimal Canal Preparations on the Fracture Resistance of Mandibular Molars: A 3-Dimensional Finite Element Analysis

IntroductionThis study compared the residual tooth strength and stress distribution of a mandibular molar prepared with different variable tapered file systems using finite element analysis (FEA). MethodsTwo preaccessed mandibular molar TruTeeth (Endo 3DP; Acadental, Lenexa, KS) were subjected to simulated endodontic treatment in this study. One tooth was instrumented with ProTaper Gold (Dentsply Tulsa Dental Specialties, Tulsa, OK), and the other was instrumented with V-Taper 2H (SS White Dental, Lakewood, NJ). The 2 teeth were scanned using micro–computed tomographic imaging, and stereolithographic surface meshes were developed for FEA. Each model was subjected to a 200-N multipoint load-simulating mastication. The results of the FEA provided quantitative and qualitative measurements for von Mises stress distribution and total deformation. ResultsThe maximum von Mises stress was greater in the ProTaper Gold–prepared model than the V-Taper 2H prepared model. In both models, total deformation values were highest in the clinical crown on the buccal aspect of the tooth. The highest stress values were found in the pericervical dentin, and stress decreased apically through the root. ConclusionsWithin the limitations of this study, it can be concluded that the maximum stress values within the tooth prepared by ProTaper Gold were higher than those in the tooth prepared by V-Taper 2H. Canal preparation with the V-Taper 2H system preserves more pericervical dentin, which may increase the resistance to fracture.

Comparison of irrigant activation devices and conventional needle irrigation on smear layer and debris removal in curved canals. (Smear layer removal from irrigant activation using SEM).

To compare the effectiveness of smear layer and debris removal in the final rinse of curved canals of permanent molars using different commercially available irrigant activation devices. The mesial roots of 74 extracted maxillary and mandibular molars were instrumented using the Mtwo nickel-titanium rotary system (VDW GmbH, Munich, Germany). They were then randomly assigned to one of three groups, varying in their final rinse protocol. Group 1 (n=15) - conventional needle irrigation with 4% NaOCl; Group 2 (n=19) - EndoActivator® (Dentsply Tulsa Dental Specialties, Tulsa, OK, USA) with 4% NaOCl; Group 3 (n=17) - XP-endo® Finisher (FKG Dentaire SA, La Chaux-de-Fonds, Switzerland) with 4% NaOCl. After the final rinse, all canals were flushed with 1mL 15% EDTA for 60s and then flushed with saline. The roots were split longitudinally and prepared for scanning electron microscope imaging. ImageJ for Windows was utilised to assess the images for smear layer removal, while two blinded investigators assessed debris presence in the middle and apical thirds using a 5-point scale. There was no significant difference in smear layer and debris removal between treatment and control groups in the same canal zones. A significant difference was noted across different canal zones both within and across the groups. There is no statistically significant difference in effectiveness between activated irrigation techniques and manual activation. Further investigations are required to evaluate all methods available and determine the most efficient technique to irrigate successfully.

Comparative in vitro Assessment of Tooth Color Change under the Influence of Nano Fast Cement and MTA.

Statement of the Problem: Tooth color changes followed by treatment with bioceramic materials are always a matter of concern.Purpose: The aim of the present in vitro study was to compare tooth discoloration that occurs in human teeth filled with ProRoot WMTA (DENTSPLY Tulsa Dental Specialties, Tulsa, OK) and those filled with Nano Fast Cement (NFC) over the course of 3 months.Materials and Method: In this experimental study, Thirty human intact premolars were obtained. The roots of all teeth were removed by a horizontal cut about 2 mm below the cementoenamel junction. The pulp tissues were removed using a barbed broach (Mani, Tokyo, Japan).The teeth were randomly divided to 3 groups (n= 10) including the control (no material), ProRoot WMTA and NFC. The experimental materials were condensed into the crowns and the teeth ends were sealed with light-cure glass ionomer cement (GC Corporation, Tokyo, Japan). The color was assessed at TBL (baseline; after preparation of the cavities but before placement of the materials), TPO (immediately after placement of the filling material and provisional restoration), T4 (after 4weeks of storage), and T12 (after 12weeks) of storage.Results: The discoloration was evident in all teeth, immediately (TPO) after applying MTA and NFC. The highest ΔΕ was noted in WMTA at 12 weeks, followed by NFC; however, there was no significant difference between the discolorations induced by these two materials. Conclusion: Similar levels of clinically observable tooth discoloration were detected by using either WMTA or NFC.

Micro–computed Tomographic Assessment and Comparative Study of the Shaping Ability of 6 Nickel-Titanium Files: An In Vitro Study

IntroductionThis research studies and compares the shaping ability of WaveOne Gold (WG; Dentsply Tulsa Dental Specialties, Tulsa, OK), the Reciproc Blue (RB; VDW, Munich, Germany), TRUShape (TS, Dentsply Tulsa Dental Specialties), XP-endo Shaper (XP; FKG, La Chaux-de-Fonds, Switzerland), iRace (IR, FKG), and TruNatomy (TN; Dentsply Sirona, Ballaigues, Switzerland) in the preparation of moderately curved canals and using micro–computed tomographic technology. MethodsSixty lower molars with 2 mesial canals were randomly distributed into 6 groups of 10 molars and 20 canals per group (n = 20). Specimens were scanned before and after preparation using the SkyScan 1275 (Bruker microCT, Kontich, Belgium). Group 1 was treated with WG, group 2 with RB, group 3 with TS, group 4 with XP, group 5 with IR, and group 6 with TN. After instrumentation, researchers quantified the changes produced in the canal geometry in terms of surface, volume, structure thickness, surface convexity index, structure model index, percentage of surface touched, and centroids. Wilcoxon and analysis of variance tests were performed to compare the values before and after preparation and the differences between groups. The significance level was established at 5%. ResultsThere were no significant differences between WG and RB (P > .05) and between TN and XP (P > .05). TN had significant differences with WG, RB, TS, and IR (P < .05). All the files produced similar apical transportation (P > .05). ConclusionsWG and RB and TN and XP had similar shaping effectivity. TS and WG touched the highest percentages of canal surfaces (81% and 73%, respectively) but produced the biggest changes in the canal anatomy. TN and XP better kept the canal anatomy, but TN touched the lowest percentage of canal surface (50%). All the files used were able to clean and to shape moderately curved canals with minimal apical transportation.

Evaluation of Torsional Resistance and Bending Stiffness of Coronal Flaring Nickel-Titanium Instruments.

Objective:The aim of this study was to evaluate the bending and torsional resistance of the following instruments: Mtwo 25/.07 (MT - VDW, Munich, Germany), Navigator W-XN 25.07 (WXN - Wizard Navigator, Medin, Nové Město na Moravě, Czech Republic), ProTaper Universal SX 19/.04 (PSX - Dentsply Tulsa Dental Specialties, Tulsa, USA), MK Orifice Shapper 17/.08 (OS - MK Life Medical and Dental Products, Porto Alegre, Brazil) and MK Sequence 17.12 (MKS - MK Life Medical and Dental Products, Porto Alegre, Brazil).Methods:One hundred instruments were used (n=20). Resistance to bending (n=10), torque and angular deflection (n=10) at the failure of new instruments were measured according to ISO 3630-1. Metal mass volume at 3 mm from the tip was evaluated using micro-computed tomography (micro-CT). The fractured surface of each fragment was examined by scanning electron microscopy (SEM). Data were analysed using 1-way analysis of variance and Tukey tests.Results:Torsional resistance values of MK Sequence were higher than the other groups (P<0.05). No differences were observed among MT, WXN and OS (P>0.05) and PTS, which presented the lowest values (P<0.05). MT showed the highest angular deflection (P<0.05). WXN and PSX presented no significant difference (P>0.05). PSX and OS also showed no significant differences (P>0.05). MKS instruments had the lowest angular deflection values (P<0.05). There were significant differences among all the groups in bending stiffness test (P<0.05), but PSX had the lowest torque to bend (P<0.05). MKS had the larger metal mass volume at 3 mm from the tip (P<0.05). SEM analysis showed similar and typical features of torsional failure for all instruments tested.Conclusion:In conclusion, MK Sequence 17/.12 had the highest torsional fracture resistance. Mtwo 25/.07 showed higher angular deflection capacity, and ProTaper Universal SX the 19/.04 lower bending stiffness.

Analysis of second mesiobuccal root canal instrumentation in maxillary first molars with three nickel-titanium rotary instruments: a micro-computed tomographic study.

The aim of this study was to evaluate the shaping characteristics of Protaper Universal (PTU; Dentsply Tulsa Dental Specialties, Johnson City, TN), Hero Shaper (HS; MicroMega, Besacon, France) and Hyflex CM (HCM; Coltene-Whaledent, Allstetten, Switzerland) nickel-titanium systems with various apical sizes and tapers in second mesiobuccal (MB2) canal instrumentation using micro-computed tomographic imaging. A total of 27 maxillary first molars with independent patent MB2 canals were selected and randomly assigned to three groups according to the 3-dimensional morphologic aspects obtained from preoperative micro-computed tomographic scans. Canals were first negotiated with a size 8K-file and finally prepared to F1, F2, and F3 with PTU and to sizes 20.04 taper, 25.04 taper, and 30.04 taper with HS and HCM. Postoperative scans were performed after each instrumentation with the same parameters used in the initial scan. The canal volume, canal transportation, untouched canal surface and wall thickness were measured and calculated using Mimics 10.01 software (Image Works, Materialise, Belgium). Statistical analysis was performed using one-way analysis of variance post hoc LSD tests. PTU removed more dentin than HS and HCM in all sections when instrumented to the same apical size (P < 0.05). HS and HCM presented a lower mean value of canal transportation than PTU in all measured sizes and sections. PTU presented a lower mean value of distal wall thickness than HS and HCM at the level of 1 and 2mm below the furcation region in all measured sizes. In conclusion, for MB2 canal instrumentation, HS and HCM of 0.04 taper are safer than PTU.

Comparative Assessment of the Shaping and Cleaning Abilities of M-Pro and Revo-S versus ProTaper Next Rotary Ni-Ti Systems: An In Vitro study

Objective: The aim of the present study was to compare the canal transportation, centering ratio, debris and smear layer score after using 3 rotary Ni-Ti systems, Revo-S (RS; Micro-Mega, Besancon Cedex, France) and ProTaper Next (PTN; Dentsply Tulsa Dental Specialties, Tulsa, OK) and M-Pro system( Guangdong, China, Mainland). Material and methods: Thirty nine mesiobuccal root canals of extracted lower first molars with 20˚ to 45˚ angle of curvature and were divided randomly into 3 groups of 13 samples each: group RS, group M-Pro and group PTN. Root canal transportation and centering ratio were evaluated at 3, 6 and 9 mm from apex using i-CAT CBCT (Hatfield, pennsylvania ,USA) before and after preparation.Thirteen Roots from each group were split longitudinally using diamond disc, by making a groove on buccal and lingual side of root without reaching the lumen of the canal.The root halves were examined under Scan Electron Microscope (SEM) by magnification x 1000 and x 4000 for debris and smear layer respectively The significance level was set at P ≤ 0.05. Results: There was no statistically significant difference in canal transportation, canal centering ratio, debris and smear layer score between the three tested groups. Conclusion: From the obtained results and within the limitations of this study, the following could be concluded:M-Pro Nickel Titanium rotary system had a negligible effect on root canal transportation which was similar to the ProTaper Next and Revo-S systems and no system was able to clean the root canal system completely.

Micro–computed Tomographic Assessment of Supplementary Cleaning Techniques for Removing Bioceramic Sealer and Gutta-percha in Oval Canals

IntroductionThe aim of this study was to conduct a micro–computed tomographic assessment of the effectiveness of 3 supplementary cleaning techniques in reducing the residual volume of gutta-percha and a bioceramic sealer after performing endodontic retreatment procedures in teeth with oval canals. MethodsThirty-six mandibular premolars were instrumented with the ProTaper Next system (instruments X1–X3; Dentsply Maillefer, Ballaigues, Switzerland) and filled with gutta-percha and Bio-C Sealer (Angelus, Londrina, PR, Brazil) using the single-cone technique. The teeth were reinstrumented with the Reciproc R40 instrument (VDW, Munich, Germany) and divided into 3 groups according to the supplementary cleaning technique used (n = 12): ultrasonic-assisted irrigation (UAI), EndoActivator (Dentsply Tulsa Dental Specialties, Tulsa, OK) irrigation (EAI), or the XP-endo Finisher R system (XPR; FKG Dentaire, La Chaux-de-Fonds, Switzerland). Micro–computed tomographic imaging was used to quantify the residual volume of filling material. One-way analysis of variance complemented by the Tukey test was used to perform the statistical analysis (P < .05). ResultsSignificant reductions were obtained in the residual filling material after supplementary cleaning (P < .05). XPR (47.5%) led to significantly greater (P < .05) filling material removal than UAI (16.6%) or EAI (22.6%). The removal values of the 2 latter systems were not significantly different. ConclusionsXPR was more effective than UAI and EAI in removing filling material in mandibular premolars with oval canals. None of the tested supplementary cleaning techniques completely removed the residual filling material.

Biocompatibility and Bioactivity of Set Direct Pulp Capping Materials on Human Dental Pulp Stem Cells.

In this study, we assessed the biocompatibility and bioactivity of various pulp capping materials—ProRoot MTA (Dentsply Tulsa Dental Specialties), Biodentine (Septodont), TheraCal LC (Bisco), and Dycal (Dentsply Caulk)—on human dental pulp stem cells (hDPSCs). Experimental disks (diameter, 7 mm; height, 4 mm) were stored in a humified incubator at 37 °C for 48 h. Then, the pulp capping materials were tested for cytotoxic effects by methyl-thiazoldiphenyl-tetrazolium and scratch wound healing assays, and for mineralization potential by Alizarin red S (ARS) staining assay and alkaline phosphatase enzyme (ALP) activity. Cell viability and cell migration did not significantly differ between ProRoot MTA, Biodentine, and control (p > 0.05). TheraCal LC exhibited slower cell migration on days 2–4 compared to control (p < 0.05), and Dycal showed no cell migration. ALP activity was highest with Biodentine on days 10 and 14, and was lowered with TheraCal LC and Dycal (p < 0.05). In the ARS assay, hDPSCs grown in ProRoot MTA and TheraCal LC eluates showed significantly increased mineralized nodule formation on day 21 compared to Biodentine, Dycal, and control (p < 0.05). These findings indicate that ProRoot MTA, Biodentine, and TheraCal LC exhibit better biocompatibility and bioactivity than Dycal.

Effect of Curvature Location on Fatigue Resistance of Five Nickel-titanium Files Determined at Body Temperature

IntroductionThe purpose of this study was to evaluate the effect of 5 different curvature locations on the fatigue resistance of thermomechanically treated nickel-titanium (NiTi) files and superelastic NiTi files at body temperature and to document the corresponding phase transformations. MethodsEndoSequence (ES; Brasseler USA, Savannah, GA), EndoSequence CM (ESCM, Brasseler USA), K3 (SybronEndo, Orange, CA), K3XF (SybronEndo), and Vortex Blue (VB; Dentsply Tulsa Dental Specialties, Tulsa, OK) NiTi files (size 25/.04) were subjected to fatigue tests inside customized artificial canals containing a curvature of 60° and a 3-mm radius. There were 5 different canals based on the location of initial curvature; these included groups in which the distance between the canal orifice and the location of the curvature (DOC) was 5, 6, 8, 10, and 11 mm. The model canal was immersed in water at 37°C ± 1°C. The number of cycles to failure (Nf) was recorded, and the fracture surface of the fragments was examined by scanning electron microscopy. Two unused files of each brand were examined by differential scanning calorimetry. ResultsThe Nf was highest in the 10-mm and 11-mm DOC groups and lowest with the 5-mm and 6-mm DOC groups (P < .05). ESCM files had the highest fatigue resistance followed by the VB, K3XF, K3, and ES files (P < .05). ESCM files had the highest Nf (P < .05), and ES and K3 files had the lowest Nf (P < .05) depending on the curvature location. Two endothermic peaks were observed on the heating curve of the heat-treated files (ESCM, K3XF, and VB). ConclusionsThe location of the canal curvature had a significant effect on the fatigue resistance of both heat-treated and superelastic NiTi files. The fatigue life of files in the coronal curve was quite short.

Comparative Surface Morphology, Chemical Composition, and Cytocompatibility of Bio-C Repair, Biodentine, and ProRoot MTA on hDPCs.

Biocompatibility is an essential property for any vital pulp material that may interact with the dental pulp tissues. Accordingly, this study aimed to compare the chemical composition and ultrastructural morphology of Biodentine (Septodont, Saint Maur-des-Fosses, France), ProRoot MTA (Dentsply Tulsa Dental Specialties, Johnson City, TN, USA), and Bio-C Repair (Angelus, Londrina, PR, Brazil), as well as their biological effects on human dental pulp cells. Chemical element characterization of the materials was undertaken using scanning electron microscopy and energy dispersive X-ray analysis (SEM-EDX). The cytotoxicity was assessed by analyzing the cell viability (MTT assay), cell morphology (immunofluorescence assay), and cell attachment (flow cytometry assay). The results were statistically analyzed using ANOVA and Tukey’s test (p < 0.05). EDX revealed that ProRoot MTA and Biodentine were mostly composed of calcium, carbon, and oxygen (among others), whereas Bio-C Repair evidenced a low concentration of calcium and the highest concentration of zirconium. SEM showed adequate attachment of human dental pulp cells (hDPCS) to vital pulp materials and cytoskeletal alterations were not observed in the presence of material eluates. Remarkably, the undiluted Biodentine group showed higher viability than the control group cells (without eluates) at 24 h, 48 h, and 72 h (p < 0.001). Based on the evidence derived from an in vitro cellular study, it was concluded that Bio-C Repair showed excellent cytocompatibility that was similar to Biodentine and ProRoot MTA.

Accuracy of Conventional Periapical Radiography in Diagnosing Furcation Repair after Perforation Treatment

IntroductionPeriapical radiography (PR) is a diagnostic tool to be used by professionals in clinical practice. The method presents limitations, and doubts still exist about its value to evaluate furcation perforation and the reparative process of hard or soft tissues after treatment. Thus, the aim of this study was to evaluate the accuracy of PR as a diagnostic method to detect both resorption of the furcation area after induced experimental perforation and repair after perforation treatment using histopathological findings as a gold standard. MethodsThirty teeth of beagle dogs with furcation perforation were filled with Biodentine (Septodont, Saint-Maur-des-Fossés, France), ProRoot White mineral trioxide aggregate (Dentsply Tulsa Dental Specialties, Tulsa, OK), or gutta-percha and examined using PR and histology. Sensitivity, specificity, predictive values, and accuracy were calculated. ResultsPR detected repair and reabsorption of furcation perforation in 55% and 48% of the teeth, respectively. Histologic analysis showed furcation perforation in 66% and 21% of the teeth, respectively. Sensitivity and specificity of PR for the detection of repair were 0.84 and 1, respectively, whereas for resorption detection, the values were 0.43 and 0.65, respectively. Diagnostic accuracy for PR was 0.89 and 0.72 for repair and resorption of furcation perforation, respectively. PR showed more accurate diagnostic (true positives + true negatives/total) in repair detection compared with resorption of furcation perforation. ConclusionsWe conclude that PR is not adequate in detecting resorption progress after the treatment of furcation perforation, and we encourage the use of digital imaging when suspicious of a possible unsuccessful result after furcation perforation treatment.