Journal of Endodontics RSS feed: Current Issue. The Journal of Endodontics , the official journal of the American Association of Endodontists, publishes scientific articles, case reports and comparison studies evaluating materials and methods of pulp conservation and endodontic treatment. Endodontists and general dentists can learn about new concepts in root canal treatment and the latest advances in techniques and instrumentation in the one journal that helps them keep pace with rapid changes in this field. The Journal of Endodontics is ranked 7th of 55 Dentistry, Oral Surgery & Medicine category on the 2009 Journal Citation Reports®, published by Thomson Reuters, and has an Impact Factor of 2.727.http://www.jendodon.com/?rss=yesElsevier Inc.en © 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved. Journal of Endodontics0099-2399363March 2010 © 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved. healthpermissions@elsevier.comhttp://www.jendodon.com/article/PIIS0099239909010103/abstract?rss=yesAbstract: Introduction: Anesthetic efficacy of inferior alveolar nerve block decreases in patients with irreversible pulpitis. It was hypothesized that premedication with nonsteroidal anti-inflammatory drugs might improve the success rates in patients with inflamed pulps.Methods: Sixty-nine adult volunteers who were actively experiencing pain participated in this prospective, randomized, double-blind study. The patients were divided into 3 groups on a random basis and were randomly given 1 of the 3 drugs including ibuprofen, ketorolac, and placebo 1 hour before anesthesia. All patients received standard inferior alveolar nerve block of 2% lidocaine with 1:200,000 epinephrine. Endodontic access preparation was initiated after 15 minutes of initial inferior alveolar nerve block. Pain during treatment was recorded by using a Heft Parker visual analog scale. Success was recorded as none or mild pain.Results: Statistical analysis with nonparametric χ2 tests showed that placebo gave 29% success rate. Premedication with ibuprofen gave 27%, and premedication with ketorolac gave 39% success rate. There was no significant difference between the 3 groups.Conclusions: Preoperative administration of ibuprofen or ketorolac has no significant effect on success rate of inferior alveolar nerve block in patients with irreversible pulpitis.Comparative Evaluation of Effect of Preoperative Oral Medication of Ibuprofen and Ketorolac on Anesthetic Efficacy of Inferior Alveolar Nerve Block with Lidocaine in Patients with Irreversible Pulpitis: A Prospective, Double-blind, Randomized Clinical TrialVivek Aggarwal, Mamta Singla, Debipada Kabi10.1016/j.joen.2009.11.010Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4CONSORT Randomized Clinical Trials375378http://www.jendodon.com/article/PIIS0099239909011078/abstract?rss=yesAbstract: Introduction: The purpose of this prospective, randomized, double-blind, placebo-controlled study was to determine the effect of the administration of preoperative ibuprofen on the success of the inferior alveolar nerve block (IAN) in patients with irreversible pulpitis.Methods: One hundred endodontic emergency patients diagnosed with irreversible pulpitis of a mandibular posterior tooth randomly received, in a double-blind manner, identical capsules of either 800 mg ibuprofen or placebo 45 minutes before the administration of a conventional IAN block. Access was begun 15 minutes after completion of the IAN block, and all patients had profound lip numbness. Success was defined as no or mild pain (visual analogue scale recordings) on access or initial instrumentation.Results and Conclusions: The success rate for the IAN block was 41% with ibuprofen and 35% with placebo, with no significant difference (P = .57) between the 2 groups. For mandibular posterior teeth, a dose of 800 mg of ibuprofen given 45 minutes before the administration of the IAN block did not result in a statistically significant increase in anesthetic success in patients with irreversible pulpitis.Effect of Preoperative Ibuprofen on the Success of the Inferior Alveolar Nerve Block in Patients with Irreversible PulpitisMark Oleson, Melissa Drum, Al Reader, John Nusstein, Mike Beck10.1016/j.joen.2009.12.030Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4CONSORT Randomized Clinical Trials379382http://www.jendodon.com/article/PIIS0099239909008978/abstract?rss=yesAbstract: Introduction: Four generations of methacrylate resin–based sealers have been available commercially. Three of these were introduced during the last 5 years when the concept of simultaneous bonding of root canal sealers to root filling materials and dentin was popularized.Methods: This article presents an overview of methacrylate resin–based sealers, with the objectives of clarifying the behavior of these materials and delineating their limitations in clinical application.Results: The first generation sealer was introduced in the mid-1970s. The initial enthusiasm associated with its use eventually diminished as a result of its suboptimal physical, biologic, and clinical properties. With advances in self-etching adhesive technology acquired from adhesive dentistry, methacrylate resin–based sealers were reintroduced in the beginning of the 21st century to support the introduction of bondable root canal filling materials. Three different generations of these sealers have since been available commercially. Although some in vitro studies on the sealing ability, self-etching potential, biocompatibility, and removability of the sealers showed better potential over conventional nonbonding sealers, accomplishing the ideal goal of a monoblock in the root canal space with these materials is still regarded as a major challenge.Conclusions: On the basis of the in vitro and in vivo data available to date, there appears to be no clear benefit with the use of methacrylate resin–based sealers in conjunction with adhesive root filling materials at this point in their development.Critical Review on Methacrylate Resin–based Root Canal SealersYoung Kyung Kim, Simone Grandini, Jason M. Ames, Li-sha Gu, Sung Kyo Kim, David H. Pashley, James L. Gutmann, Franklin R. Tay10.1016/j.joen.2009.10.023Journal of Endodontics 36, 3 (2010)2009-12-18Journal of Endodontics2009-12-18363S0099-2399(10)X0002-4Review Articles383399http://www.jendodon.com/article/PIIS0099239909007699/abstract?rss=yesAbstract: Introduction: Mineral trioxide aggregate (MTA) has been recommended for various uses in endodontics. Two previous publications provided a comprehensive list of articles from November 1993–September 2009 regarding the chemical and physical properties, sealing ability, antibacterial activity, leakage, and biocompatibility of MTA. The purpose of Part III of this literature review is to present a comprehensive list of articles regarding animal studies, clinical applications, drawbacks, and mechanism of action of MTA.Methods: A review of the literature was performed by using electronic and hand-searching methods for the clinical applications of MTA in experimental animals and humans as well as its drawbacks and mechanism of action from November 1993–September 2009.Results: MTA is a promising material for root-end filling, perforation repair, vital pulp therapy, and apical barrier formation for teeth with necrotic pulps and open apexes. Despite the presence of numerous case reports and case series regarding these applications, there are few designed research studies regarding clinical applications of this material. MTA has some known drawbacks such as a long setting time, high cost, and potential of discoloration. Hydroxyapatite crystals form over MTA when it comes in contact with tissue synthetic fluid. This can act as a nidus for the formation of calcified structures after the use of this material in endodontic treatments.Conclusions: On the basis of available information, it appears that MTA is the material of choice for some clinical applications. More clinical studies are needed to confirm its efficacy compared with other materials.Mineral Trioxide Aggregate: A Comprehensive Literature Review—Part III: Clinical Applications, Drawbacks, and Mechanism of ActionMasoud Parirokh, Mahmoud Torabinejad10.1016/j.joen.2009.09.009Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Review Articles400413http://www.jendodon.com/article/PIIS0099239909010139/abstract?rss=yesAbstract: Introduction: Many recent technological advancements have been made in the field of endodontics; however, comparatively few studies have evaluated their impact on tooth survival. This study compared the survival rates of endodontic treatment performed by using classic techniques (eg, instrumentation with stainless steel hand files, alternating 5.25% NaOCl and 3% H2O2 irrigation, mostly multiple treatment visits, and so on) versus those performed using more contemporary techniques (eg, instrumentation with hand and rotary nickel-titanium files, frequent single-visit treatment, NaOCl, EDTA, chlorhexidine, H2O2 irrigation, warm vertical or lateral condensation obturation, use of surgical microscopes, electronic apex locators, and so on).Methods: Using a retrospective chart review, clinical data were obtained for 984 endodontically treated teeth in 857 patients. Survival was defined as radiographic evidence of the treated tooth being present in the oral cavity 12 months or more after initial treatment. A mixed-model Poisson regression analysis was used to compare failure rates.Results: Of the 459 teeth in the classic group, there was an overall survival rate of 98% with an average follow-up time of 75.7 months. Of 525 teeth in the contemporary group, there was an overall survival rate of 96%, with an average follow-up time of 34 months. Considerably more treatments in the classic group were completed in multiple appointments (91%) than in the contemporary group (39%). More teeth in the classic group underwent posttreatment interventions (6.7% vs 0.9%, respectively).Conclusions: No statistically significant difference was noted between the two technique groups or between single or multiple visits in terms of survival.Comparison of Classic Endodontic Techniques versus Contemporary Techniques on Endodontic Treatment SuccessChris H. Fleming, Mark S. Litaker, Larry W. Alley, Paul D. Eleazer10.1016/j.joen.2009.11.013Journal of Endodontics 36, 3 (2010)2010-01-25Journal of Endodontics2010-01-25363S0099-2399(10)X0002-4Clinical Research414418http://www.jendodon.com/article/PIIS009923990901108X/abstract?rss=yesAbstract: Introduction: This study compared the difference in pulpal blood flow between vital and root-filled teeth by using ultrasound Doppler imaging.Methods: To compare the difference in pulpal blood flow between vital and root-filled teeth, 11 patients (mean age, 32.06 years; 3 male, 8 female) who had undergone root canal treatment on the anterior tooth of the maxilla or mandible and had a vital contralateral tooth were examined. Pulpal blood flow measurements were performed on the vital and root canal–treated teeth by using ultrasound Doppler imaging. The parameters examined were the maximum linear velocity (Vas), average linear velocity (Vam), minimum linear velocity (Vakd), pulsation index (PI), and circulation resistance (RI), which are indicators of the pulpal blood flow. The differences between the vital and root-filled teeth were examined by using a paired t test at the 95% confidence interval.Results: There were significant differences in the Vas, Vam, Vakd, and RI between the vital and root-filled teeth (P < .05). With the root-filled teeth, ultrasound Doppler imaging revealed a linear and nonpulsed waveform, whereas the vital teeth showed a pulsed waveform that is characteristic of an arteriole.Conclusions: Ultrasound Doppler imaging can detect pulpal blood flow in vital tooth through indicators such as Vas, Vam, Vakd, PI, and RI.Pulpal Blood Flow Measurement with Ultrasound Doppler ImagingMin-Jung Yoon, Euiseong Kim, Seoung-Jong Lee, Young-Min Bae, Sergey Kim, Sung-Ho Park10.1016/j.joen.2009.12.031Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Clinical Research419422http://www.jendodon.com/article/PIIS0099239909009480/abstract?rss=yesAbstract: Introduction: This study investigated the differentiation of radicular cysts from granulomas. Cone beam computed tomography (CBCT) imaging was compared with the existing standard, biopsy and histopathology.Methods: Forty-five patients scheduled for an apicoectomy received a CBCT scan of the involved arch. Two oral and maxillofacial radiologists, working independently and using the same criteria, categorized the CBCT images as one of the following: cyst, likely cyst, likely granuloma, granuloma, or other. After apicoectomies, two oral pathologists, working independently and using the same criteria, diagnosed the surgical specimens as one of the following: radicular cyst, granuloma, or other. We examined the following: (1) interrater agreement between pathologists as to the biopsy diagnosis, (2) interrater agreement between radiologists as to the CBCT diagnosis, and (3) accuracy of radiologists' diagnostic assessments using histopathology as the standard.Results: Findings showed strong interrater reliability between pathologists (κ = 0.79, z = 5.46, p < 0.0001) and weak interrater reliability between radiologists (κ = 0.14, p = not significant). Accuracy (true-positives plus true-negatives) for the two radiologists was 51% and 63%.Conclusion: Under the conditions of this study, based on the inconsistency of the radiologists' reports as evidenced by statistical analyses, it was concluded that CBCT imaging is not a reliable diagnostic method for differentiating radicular cysts from granulomas. Surgical biopsy and histopathological evaluation remain the standard procedure for differentiating radicular cysts from granulomas.Evaluation of Pathologists (Histopathology) and Radiologists (Cone Beam Computed Tomography) Differentiating Radicular Cysts from GranulomasPaul A. Rosenberg, Jared Frisbie, Jaehoon Lee, Kyung Lee, Herbert Frommer, Shailesh Kottal, Joan Phelan, Louis Lin, Gene Fisch10.1016/j.joen.2009.11.005Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Clinical Research423428http://www.jendodon.com/article/PIIS0099239909010231/abstract?rss=yesAbstract: Introduction: The purpose of this prospective, randomized single-blind study was to compare the degree of pulpal anesthesia obtained with the inferior alveolar nerve (IAN) block administered by using a peripheral nerve stimulator compared with a conventional IAN block by using a cartridge of 2% lidocaine with 1:100,000 epinephrine.Methods: Forty-six adult volunteers randomly received a conventional IAN block or an IAN block administered with a peripheral nerve stimulator at 2 separate appointments. An electric pulp tester was used to test for anesthesia of the first molar, first premolar, and lateral incisor in 4-minute cycles for 60minutes. Anesthesia was considered successful when 2 consecutive 80 readings were obtained within 15minutes, and the 80 reading was continuously sustained through the 60th minute.Results: With the peripheral nerve stimulator for the IAN block, successful pulpal anesthesia ranged from 32%–37%. For the conventional IAN block, successful pulpal anesthesia ranged from 32%–45%. There was no significant difference between the 2 IAN block techniques.Conclusions: We concluded that the IAN block administered with a peripheral nerve stimulator did not increase the success rate of pulpal anesthesia when compared with a conventional IAN block.A Prospective, Randomized Single-blind Study of the Anesthetic Efficacy of the Inferior Alveolar Nerve Block Administered with a Peripheral Nerve StimulatorFredric Simon, Al Reader, Melissa Drum, John Nusstein, Mike Beck10.1016/j.joen.2009.11.023Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Clinical Research429433http://www.jendodon.com/article/PIIS0099239909010656/abstract?rss=yesAbstract: Introduction: Although many studies have reported on the morphology of maxillary first premolars, to our knowledge, there has never been an investigation reporting the anatomic position of the palatal (P) root tip relative to the B root tip in mesiodistal (MD), buccopalatal (BP), and apicocoronal (AC) dimensions. Such information could help clinicians more accurately locate root apices, reduce surgical morbidity, and improve the precision and prognosis of endodontic periradicular surgery for this tooth.Methods: Fifty extracted, bifurcated, human maxillary first premolars were individually mounted and photographed under 10× magnification and oriented to simulate a clinical view.Results: The P apex was superimposed by the B apex in 25 of 50 specimens, distal to the B apex in 24 of 50, and mesial to the B apex in only 1 instance. When not superimposed by or mesial to the B apex, the P apex was usually 1.4 ± 0.7 mm distal to the B apex. In 98% of specimens, the P apex was positioned palatocoronal or palatocoronodistal to the B apex.Conclusions: This knowledge can be used to clinically minimize the size of osteotomies required to locate P root apices during endodontic surgery.Predicting the Anatomical Position of the Palatal Root Apex in Maxillary First Premolars During Surgical Endodontic TreatmentStanton D. Widmer, James C. Kulild, Mary P. Walker, Karen B. Williams, Jerald Katz10.1016/j.joen.2009.12.013Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Clinical Research434437http://www.jendodon.com/article/PIIS0099239909010668/abstract?rss=yesAbstract: Introduction: The incisive/mental nerve block (IMNB) could be an alternative to the inferior alveolar nerve block in the mandibular anterior teeth. The effectiveness of articaine has not been tested in IMNB.Methods: This prospective randomized double-blind crossover study compared the anesthetic efficacy of 0.6 mL 4% articaine and 2% lidocaine, both with 1:100.000 epinephrine administered as IMNB to 40 volunteers in two sessions. Pulpal anesthesia of lateral incisor through premolars was tested with an electric pulp tester. The injection and postoperative pain were evaluated by using visual analog scales. The onset (time from the end of injection to the absence of pulpal response) and duration of pulpal anesthesia (time recorded before two positive responses to the pulp tester) and the anesthesia success (two consecutive readings of 80 without response and onset ≤10 minutes) were measured.Results: Articaine provided a higher success rate (p < 0.001) of anesthesia than lidocaine for the lateral incisor (32.5%), the canine (55%), and the first (72.5%) and second (80%) premolars and a faster onset (p < 0.05) for canine and increased duration (p < 0.05) of anesthesia for premolars. The median duration of premolars anesthesia was 10 and 20 minutes, respectively, with lidocaine and articaine. There were no differences in pain scores between the solutions (p > 0.05).Conclusions: Articaine promoted higher anesthesia success and longer duration of anesthesia than lidocaine for most of the teeth after IMNB although anesthesia success could be considered clinically appropriated only for premolars. The volume of local anesthetic used in the present study may not be appropriate for procedures lasting longer than 10 minutes.Anesthetic Efficacy of Articaine and Lidocaine for Incisive/Mental Nerve BlockCamila Batista da Silva, Luciana Aranha Berto, Maria Cristina Volpato, Juliana Cama Ramacciato, Rogério Heládio Lopes Motta, José Ranali, Francisco Carlos Groppo10.1016/j.joen.2009.12.014Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Clinical Research438441http://www.jendodon.com/article/PIIS009923990901070X/abstract?rss=yesAbstract: Introduction: The presence of cracks and fractures in teeth can pose difficulties in diagnosis, prognosis assessment, and treatment recommendations. When a tooth has no significant restorations or caries, whereby the pulp is nonvital in the absence of a luxation injury, it is suggested that this necrosis is likely caused by a significant longitudinal crack that extends from the occlusal surface and into the pulp. This type of presentation has been termed “fracture necrosis.”Methods: Twenty-seven teeth with nonvital pulps were evaluated that had no restorations or minimally deep restorations and no signs of caries. These teeth were extracted and evaluated as to the depth and location of any potential fracture.Results: All evaluated teeth were found to have cracks that extended from the occlusal surface into the pulp and progressed to an external root surface.Conclusion: Pulp necrosis, in the absence of restorations, caries, or luxation injuries, is likely caused by a longitudinal fracture extending from the occlusal surface and into the pulp. Based on the available literature, these types of teeth may have a poor prognosis after endodontic treatment, with the potential ramification of extensive periodontal and/or periapical bone loss. Extraction may be considered as the primary treatment option.Fracture Necrosis: Diagnosis, Prognosis Assessment, and Treatment RecommendationsLouis H. Berman, Sergio Kuttler10.1016/j.joen.2009.12.018Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Clinical Research442446http://www.jendodon.com/article/PIIS0099239909010218/abstract?rss=yesAbstract: Introduction: Although simvastatin has multiple demonstrable effects, its function in dentinogenesis remains unclear. In this study, we tested the hypothesis that the addition of simvastatin to human dental pulp cells (HDPCs) stimulates odontogenesis both by promoting odontoblastic differentiation and by favoring the release of angiogenic factors. In addition, the role of heme oxygenase-1 (HO-1) in these effects was investigated.Methods: The expression of markers for odontoblastic differentiation and angiogenesis was analyzed by means of alkaline phosphatase (ALP) activity, alizarin red staining, and Western blotting.Results: Simvastatin enhanced the differentiation of HDPCs by up-regulating mineralization nodules and odontogenic markers as well as angiogenic markers. These phenomena were then correlated with the induction of HO-1 protein levels. The inducing effect of simvastatin on odontoblastic differentiation and angiogenesis was nullified by an HO-1 inhibitor and a carbon monoxide (CO) scavenger.Conclusions: These results suggested that simvastatin exerts its odontoblastic differentiation and angiogenesis-inducing effects in HDPCs through a mechanism that involves the action of HO-1 and its product CO.Simvastatin Promotes Odontoblastic Differentiation and Expression of Angiogenic Factors via Heme Oxygenase-1 in Primary Cultured Human Dental Pulp CellsKyung-San Min, Young-Man Lee, Sung-Ok Hong, Eun-Cheol Kim10.1016/j.joen.2009.11.021Journal of Endodontics 36, 3 (2010)2010-01-25Journal of Endodontics2010-01-25363S0099-2399(10)X0002-4Biology447452http://www.jendodon.com/article/PIIS0099239909010188/abstract?rss=yesAbstract: Introduction: Dental pulp is often exposed to ischemia in case of injury or inflammation because of narrow vascular openings at the apex and poor blood circulation in dental pulp tissue. Resident stem cell populations are thought to contribute to the postischemic regeneration process. The aim of this study was to investigate the influence of simulated ischemia (serum deprivation and hypoxia) on side population (SP) stem cells of human dental pulp cells in order to provide a better understanding of the postischemic tissue repair and regeneration process.Methods: The proliferation of dental pulp cells (DPCs) after exposure to ischemic culture conditions (2% O2, 2% serum) for 24 hours and 48 hours was investigated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. The SP fraction was detected by Hoechst 33342 fluorescence flow cytometry, and the expression of SP marker ABCG2 was investigated by immunofluorescence. ABCG2 and OCT4 messenger RNA levels before and after transient ischemia were determined by real-time polymerase chain reaction.Results: Proliferation rate of DPCs was lower in 24- and 48-hour ischemic groups than control from day 5 to day 7. SP proportion was significantly higher 24 and 48 hours after simulated ischemic treatment, and immunofluorescence staining of ABCG2 also verified the increasing trend of side population. ABCG2 and OCT4 messenger RNA levels increased more than three folds in 48 hours ischemic group compared with control group.Conclusions: Side population in dental pulp cells increase notably after transient simulated ischemic culture, suggesting that SP may participate in post-ischemic repair and regeneration process of dental pulp.Side Population Increase after Simulated Transient Ischemia in Human Dental Pulp CellJinming Wang, Xi Wei, Junqi Ling, Yijun Huang, Qimei Gong10.1016/j.joen.2009.11.018Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Biology453458http://www.jendodon.com/article/PIIS0099239909010632/abstract?rss=yesAbstract: Introduction: Bacterial infection and resulting inflammation of the dental pulp might not only trigger neuroimmune interactions in this tissue but also sensitize the central nervous system (CNS) such as the thalamus via nociceptive neurons. Thus, immunopathologic changes in the rat thalamus that take place after pulp inflammation were investigated.Methods: Pulp exposure was made in mandibular right first molars of 5-week-old Wistar rats. After 24 hours, the thalamus was retrieved and subjected to either immunohistochemistry for class II major histocompatibility complex (MHC) molecules and glial fibrillary acidic protein (GFAP) or mRNA expression analysis of antigen-presenting cell–related molecules and N-methyl-D-aspartate receptor 2D subunit (NR2D) by means of reverse transcription–polymerase chain reaction (RT-PCR) and real-time PCR.Results: At 24 hours after pulp exposure, the density of class II MHC molecule–expressing and GFAP-expressing cells was increased in the contralateral thalamus. Gene expression analysis revealed the up-regulation of class II MHC molecules, CD80, CD83, CD86, and NR2D in the contralateral thalamus, as compared with the ipsilateral thalamus.Conclusions: These results suggest the signal of pulp inflammation induces neuronal activation in the CNS.Artificial Dental Pulp Exposure Injury Up-regulates Antigen-Presenting Cell–related Molecules in Rat Central Nervous SystemTomoatsu Kaneko, Mitsuhiro Kaneko, Uraiwan Chokechanachaisakul, Jun Kawamura, Reika Kaneko, Mitsuhiro Sunakawa, Takashi Okiji, Hideaki Suda10.1016/j.joen.2009.12.011Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Biology459464http://www.jendodon.com/article/PIIS0099239909010607/abstract?rss=yesAbstract: Introduction: Mineral trioxide aggregate (MTA) and calcium silicate (CS) cements exhibit acceptable physical and chemical properties. The aim of the present study was to evaluate the effects of MTA and CS cements on inflammatory reactions in primary cultured human dental pulp cells.Methods: The mitochondrial colorimetric assay was used to evaluate pulp cell survival rates. Fluorescent immunohistochemistry was used to observe focal adhesion kinase (FAK) and cyclooxygenase-2 (COX-2) distributions in the cells. Reverse transcription–polymerase chain reaction was used to assess COX-2 expression.Results: The results showed that MTA and CS are biocompatible with pulp cells (P > .05). FAK was well-distributed in pulp cells in contact with both cements. Both MTA and CS cements induced pulp cell inflammation as evidenced by increased COX-2 expression.Conclusions: The present study demonstrated that MTA and CS cements are biocompatible with primary cultured pulp cells. Both cements can induce inflammatory COX-2 expression in the pulp cells.Expression of the Inflammatory Marker Cyclooxygenase-2 in Dental Pulp Cells Cultured with Mineral Trioxide Aggregate or Calcium Silicate CementsChih-Lin Chen, Chia-Tze Kao, Shinn-Jyh Ding, Ming-You Shie, Tsui-Hsien Huang10.1016/j.joen.2009.12.008Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Biology465468http://www.jendodon.com/article/PIIS0099239909010991/abstract?rss=yesAbstract: Introduction: Mesenchymal stem cells display extensive proliferative capacity of multilineage differentiation. The stromal compartment of mesenchymal tissues is considered to harbor stem cells. We assessed the endodermal differentiation of mesenchymal cells from deciduous and wisdom tooth pulp.Methods: Dental mesenchymal cells were isolated and expanded in vitro. After cell cultures had been established, cells were characterized using known stem cell markers. For hepatic differentiation the media was supplemented with hepatic growth factor, dexamethasone, Insulin-Transferrin-Selenium-X, and oncostatin.Results: Both cultures showed a number of cells positive for specific hepatic markers including α-fetoprotein, albumin, and hepatic nuclear factor 4α after differentiation. Also, small clusters of cells positive for insulin-like growth factor 1 were found. The concentration of urea increased significantly in the media. Moreover, a significant amount of glycogen was found in the cells.Conclusion: Because the cells proved to produce specific hepatic proteins and to start functions specific for hepatocytes, such as storing glycogen and urea production, we may state that the mesenchymal cell cultures from wisdom and deciduous tooth pulp acquired morphologic and functional characteristics of hepatocytes.Deciduous and Permanent Dental Pulp Mesenchymal Cells Acquire Hepatic Morphologic and Functional Features In VitroNikolay Ishkitiev, Ken Yaegaki, Bogdan Calenic, Taka Nakahara, Hiroshi Ishikawa, Vanyo Mitiev, Markus Haapasalo10.1016/j.joen.2009.12.022Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Biology469474http://www.jendodon.com/article/PIIS009923990901111X/abstract?rss=yesAbstract: Introduction: Collagen-degrading matrix metalloproteinases (MMPs) are expressed by odontoblasts and present in dentin. We hypothesized that odontoblasts express other collagen-degrading enzymes such as cysteine cathepsins, and their activity would be present in dentin, because odontoblasts are known to express at least cathepsin D. Effect of transforming growth factor beta (TGF-β) on cathepsin expression was also analyzed.Methods: Human odontoblasts and pulp tissue were cultured with and without TGF-β, and cathepsin gene expression was analyzed with DNA microarrays. Dentin cathepsin and MMP activities were analyzed by degradation of respective specific fluorogenic substrates.Results: Both odontoblasts and pulp tissue demonstrated a wide range of cysteine cathepsin expression that gave minor responses to TGF-β. Cathepsin and MMP activities were observed in all dentin samples, with significant negative correlations in their activities with tooth age.Conclusions: These results demonstrate for the first time the presence of cysteine cathepsins in dentin and suggest their role, along with MMPs, in dentin modification with aging.Cysteine Cathepsins in Human Dentin-Pulp ComplexIvarne L. Tersariol, Saulo Geraldeli, Christiane L. Minciotti, Fábio D. Nascimento, Virve Pääkkönen, Marília T. Martins, Marcela R. Carrilho, David H. Pashley, Franklin R. Tay, Tuula Salo, Leo Tjäderhane10.1016/j.joen.2009.12.034Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Biology475481http://www.jendodon.com/article/PIIS0099239909010206/abstract?rss=yesAbstract: Introduction: New filling biomaterials with better physicochemical properties would create a favorable biologic environment for the healing of periapical tissues. The aim of this study was to evaluate periapical repair after biomechanical preparation and root filling with an adhesive system compared with the gold standard material (gutta-percha + sealer) in dog teeth.Methods: The pulp of 25 root canals was removed. The apical cementum layer was perforated, and the root canals were prepared up to size #60 K-file followed by step-back shaping with the #90 K-file and filled by the lateral condensation technique. In the experimental group (n = 15), the Resilon System (Pentron Clinical Technologies, Wallingford, CT) was used. As a control material (n = 10), gutta-percha cones and pulp canal sealer were used. After 60 days, the animals were killed, and 10 histologic parameters were evaluated. Differences among the groups were analyzed by using the Mann-Whitney and Fisher exact tests.Results: In radiographic and histologic evaluations, most fillings were slightly short of the apex. Progressive regenerative stages were observed; however, there was a reduced prevalence of biologic foraminal closure. No significant differences were observed between the 2 biomaterials with regard to any of the parameters evaluated (P > .05).Conclusions: The Resilon System shows periapical biocompatibility equivalent to the gold standard material.Periapical Repair in Dog Teeth: Root Canal Adhesive Filling by Using the Resilon SystemDébora Silveira Brasil, Janir Alves Soares, Martinho Campolina Rebello Horta, Cynthia Lopes Ferreira, Eduardo Nunes, Guilherme G. Chaves, Frank Ferreira Silveira10.1016/j.joen.2009.11.020Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Technology482488http://www.jendodon.com/article/PIIS0099239909009467/abstract?rss=yesAbstract: Introduction: The antimicrobial agents chlorhexidine and doxycycline bind to dentin to provide sustained antimicrobial action. This study measured the stability of these chemicals on dentin adjacent to the root canal.Methods: Extracted human teeth were instrumented and irrigated with either MTAD or Endo-CHX. After aging at 37°C, the canals were enlarged by 0.3 mm, dentin debris was collected, and compounds were extracted. The amount of doxycyline or chlorhexidine was measured by using reverse-phase high-performance liquid chromatography.Results: After 1 day of aging, the canals contained 3.4 ± 1.3 μg doxycycline or 43 ± 20 μg chlorhexidine. The half-lives of doxycycline and chlorhexidine were calculated to be 3.0 weeks and 14 weeks, respectively. Groups monitoring decomposition of dilute doxycycline or chlorhexidine in water had half-lives of 5.8 weeks and 40 weeks, respectively. The half-life of the antimicrobials on dentin is suspected to be largely due to diffusion of the antimicrobials.Conclusions: Compared with doxycycline, chlorhexidine is more stable on root canal dentin.Stability of Doxycycline and Chlorhexidine Absorbed on Root Canal DentinBrian J. Rasimick, Jeffrey Wan, Barry L. Musikant, Allan S. Deutsch10.1016/j.joen.2009.11.003Journal of Endodontics 36, 3 (2010)2010-01-18Journal of Endodontics2010-01-18363S0099-2399(10)X0002-4Technology489492http://www.jendodon.com/article/PIIS0099239909009522/abstract?rss=yesAbstract: Introduction: Retreatment procedures might affect the adhesion capability of refilling materials to dentinal walls. The purpose of this study was to compare the effect of different retreatment techniques on bond strength of Resilon (Resilon Research LLC, Madison, CT)/Epiphany (Pentron Clinical Technologies, LLC, Wallingford, CT) self-etch (SE) with radicular dentin after canal reobturation.Methods: Sixty extracted single-rooted human teeth were prepared using Mtwo rotary files (VDW, Munich, Germany) and obturated with Resilon/Epiphany SE. The roots were randomly divided into four groups; in group 1, no retreatment procedure was done; group 2 was retreated using Mtwo R/Mtwo files; group 3 was retreated using Mtwo R/Mtwo combined with chloroform; and group 4 was retreated using Mtwo R/Mtwo combined with Endosolv R (Septodont, Paris, France). The root canals were then reobturated with Resilon/Epiphany SE. One-millimeter slices of midroot dentin were prepared for the push-out test (n = 30 slices per group). Failure modes after the push-out test were examined under microscopy. The data were analyzed by using a one-way analysis of variance and the Dunnett post hoc test.Results: Group 3 showed significantly the lowest mean bond strength (p < 0.02). No significant difference was found between the values of groups 1, 2, and 4 (p > 0.26). The mode of bond failure was predominantly adhesive for all groups.Conclusions: This study showed that the bond strength of Resilon/Epiphany SE after root canal retreatment using Mtwo files, either alone or combined with Endosolv R, was not significantly different from that of nonretreated specimens. Chloroform used for retreatment had an adverse effect on the bond strength of Resilon/Epiphany SE after root canal reobturation.Push-out Bond Strength of Resilon/Epiphany Self-etch to Intraradicular Dentin after Retreatment: A Preliminary StudyNoushin Shokouhinejad, Mohammad A. Sabeti, Mahboubeh Hasheminasab, Farhad Shafiei, Ahmad Reza Shamshiri10.1016/j.joen.2009.11.009Journal of Endodontics 36, 3 (2010)2010-01-25Journal of Endodontics2010-01-25363S0099-2399(10)X0002-4Technology493496http://www.jendodon.com/article/PIIS0099239909010140/abstract?rss=yesAbstract: Introduction: This study evaluated the effects of three different endodontic sealers on the bond strength of a fiber post cemented with adhesive resin cement.Methods: Forty-eight extracted maxillary central incisors were prepared with the step-back technique and randomly divided into four groups (n = 12 for each group): group 1, control group (gutta-percha points only, no sealer); group 2, resin-based sealer (AH plus; Dentsply De Trey GmbH, Konstanz, Germany); group 3, zinc oxide–eugenol-based sealer (Endofill; Produits Dentaires SA, Vevey, Switzerland); and group 4, calcium hydroxide–based sealer (Sealapex; Kerr, Romulus, MI). The roots were obturated with gutta-percha using the cold lateral compaction technique. Fiber posts were cemented into the prepared post spaces with the adhesive resin cement Panavia F 2.0 (Kuraray Medical, Okayama, Japan). A push-out test was performed in a universal machine, and failure modes were observed. Morphologic changes of the root canal dentin surfaces were examined with scanning electron microscopy (SEM).Results: One-way analysis of variance revealed that sealers have significant effects on bond strength (p < 0.05). The control group had the highest mean push-out bond strength. No statistical difference was detected between the eugenol-based sealer group and the resin-based sealer group (p > 0.05). The root surfaces were covered with the smear layer and debris in all the groups after post space preparation in SEM analysis. However, some of the dentin tubules were partially open in the control and calcium hydroxide–based sealer groups after the application of the resin monomer.Conclusion: The results of this study showed that the type of canal sealer and chemomechanical preparation of the root canals affect the bond strength of a fiber post cemented with resin cement.Effects of Three Canal Sealers on Bond Strength of a Fiber PostEbru Özsezer Demiryürek, Şafak Külünk, Gözde Yüksel, Duygu Saraç, Bilinç Bulucu10.1016/j.joen.2009.11.014Journal of Endodontics 36, 3 (2010)2010-01-25Journal of Endodontics2010-01-25363S0099-2399(10)X0002-4Technology497501http://www.jendodon.com/article/PIIS0099239909008929/abstract?rss=yesAbstract: Introduction: Mineral trioxide aggregate (MTA) is composed of calcium silicate cement and bismuth oxide added for radiopacity. The bismuth oxide in MTA has been reported to have a deleterious effect on the physical and chemical properties of the hydrated material. This study aimed to investigate the hydration mechanism of calcium silicate cement loaded with different radiopacifiers for use as a root-end filling material.Methods: Calcium silicate cement loaded with barium sulfate, gold, or silver/tin alloy was hydrated, and paste microstructure was assessed after 30 days. In addition, atomic ratio plots of Al/Ca versus Si/Ca and S/Ca and Al/Ca were drawn, and X-ray energy dispersive analysis of the hydration products was performed to assess for inclusion of heavy metals. The leachate produced from the cements after storage of the cements in water for 28 days and the leaching of the radiopacifiers in an alkaline solution was assessed by using inductively coupled plasma.Results: The hydrated calcium silicate cement was composed of calcium silicate hydrate, calcium hydroxide, ettringite, and monosulfate. Unhydrated cement particles were few. No heavy metals were detected in the calcium silicate hydrate except for the bismuth in MTA. Calcium was leached out early in large quantities that reduced with time. The barium and bismuth were leached in increasing amounts. Copper was the most soluble in alkaline solution followed by bismuth and barium in smaller amounts.Conclusions: The bismuth oxide can be replaced by other radiopacifiers that do not affect the hydration mechanism of the resultant material.Hydration Characteristics of Calcium Silicate Cements with Alternative Radiopacifiers Used as Root-end Filling MaterialsJosette Camilleri10.1016/j.joen.2009.10.018Journal of Endodontics 36, 3 (2010)2010-01-25Journal of Endodontics2010-01-25363S0099-2399(10)X0002-4Technology502508http://www.jendodon.com/article/PIIS0099239909008826/abstract?rss=yesAbstract: Introduction: The purpose of this investigation was to compare the antimicrobial efficacy of root canal irrigation with the EndoVac (Discus Dental, Culver City, CA) to endodontic needle irrigation in the apical 5 mm of root canals infected with Enterococcus faecalis.Methods: Bilaterally matched, extracted human teeth were sterilized and inoculated with E. faecalis. Specimens in the EndoVac group were irrigated using the EndoVac system, whereas those in the needle group were irrigated with a 30-G side-vented needle. After chemomechanical preparation, the apical 5 mm of the roots were removed, frozen in liquid nitrogen, and pulverized to expose E. faecalis in dentinal tubules or other morphologic irregularities. The number of colony forming units (cfus) of E. faecalis per mg dentin was determined.Results: The EndoVac Group had a mean of 31.6 cfu/mg, whereas the needle group had a mean of 157 cfu/mg. This represents a bacterial reduction of 99.7% in group A and 98.8% in group B when compared with positive controls.Conclusion: Although there were fewer cfu/mg when using the EndoVac, there was not a statistically significant difference between the EndoVac and needle groups.Comparison of the Antimicrobial Efficacy of Irrigation Using the EndoVac to Endodontic Needle DeliveryTodd A. Miller, J. Craig Baumgartner10.1016/j.joen.2009.10.008Journal of Endodontics 36, 3 (2010)2010-01-25Journal of Endodontics2010-01-25363S0099-2399(10)X0002-4Technology509511http://www.jendodon.com/article/PIIS0099239909009479/abstract?rss=yesAbstract: Introduction: There is ongoing debate regarding the ideal sequence, volume, and concentration of irrigants, length of time for irrigation, and irrigation technique to achieve debridement of the root canal system. The aim of this study was to verify the impact of the final rinse technique on smear layer removal ability of 17% ethylenediaminetetraacetic acid (EDTA).Methods: Sixteen single-rooted human teeth were instrumented and divided into 2 groups at the final rinse step according to the following final rinse techniques used: continuous rinse group, continuous rinse with EDTA during 3 minutes, and rinse and soaking group, rinse with 1 mL of EDTA, soaking of the canal for 2 minutes and 30 seconds, and rinse completion with the remaining 4 mL for 30 seconds. The specimens were split lengthwise and observed under scanning electron microscope.Results: Data were analyzed with Kruskal-Wallis and Dunn tests. The continuous rinse group presented more debris-free surfaces when compared with the rinse and soaking group (P < .01). When the root canal areas were compared within the groups, no statistical differences were found (P > .05).Conclusions: It can be concluded that a continuous rinse with 5 mL of EDTA for 3 minutes can more efficiently remove the smear layer from root canal walls.Influence of Final Rinse Technique on Ability of Ethylenediaminetetraacetic Acid of Removing Smear LayerIsabel Mello, Brigitte Alvarado Kammerer, Daiana Yoshimoto, Mary Caroline Skelton Macedo, João Humberto Antoniazzi10.1016/j.joen.2009.11.004Journal of Endodontics 36, 3 (2010)2010-01-25Journal of Endodontics2010-01-25363S0099-2399(10)X0002-4Technology512514http://www.jendodon.com/article/PIIS0099239909010115/abstract?rss=yesAbstract: Introduction: The biocompatibility of chelating agents and organic acids have been explained by a variety of methods, and suggestions for use have been based more on clinical observations and physicochemical properties than on biological aspects. The present study aimed to evaluate the inflammatory response of 17% EDTA, 17% EDTA-T, and 10% citric acid in bony defect created in rat jaws.Methods: Mandibular through and through critical size defects were created bilaterally in 60 rats. Fibrinol (Baldacchi SA, São Paulo, Brazil), a cube-shaped compound of absorbable bovine fibrin foam and sodium chloride, was used as a carrier of the substances. One side had received Fibrinol (control), whereas the opposite side had received Fibrinol soaked with each substance on the 1st, on the 7th, on the 14th, and on the 28th day (n = 5 for each day). Hemijaws were prepared for light microscopy, and samples were stained with hematoxylin and eosin. Digitized images were analyzed with a morphometric software (ImageJ; National Institute of Mental Health, Bethesda, MD). to obtain the number of inflammatory cells per area. Comparisons were performed by using the Kruskal-Wallis test (p = 0.05).Results: For all days, 10% citric acid and 17% EDTA-T showed, respectively, the lowest and highest number of inflammatory cells per area. All tested substances and controls showed the highest inflammatory cell response on the 14th day.Conclusion: Among the tested substances, 10% citric acid proved to be the less aggressive tested solution at 14 days. At 28 days, all solutions were similar, but EDTA-T kept showing the higher number of inflammatory cells.Evaluation of Inflammatory Response of EDTA, EDTA-T, and Citric Acid in Animal ModelMíriam F. Zaccaro Scelza, Viviane Santos da Silva Pierro, Mauricio Alves Chagas, Licinio Esmeraldo da Silva, Pantaleo Scelza10.1016/j.joen.2009.11.011Journal of Endodontics 36, 3 (2010)2010-01-25Journal of Endodontics2010-01-25363S0099-2399(10)X0002-4Technology515519http://www.jendodon.com/article/PIIS0099239909010577/abstract?rss=yesAbstract: Introduction: The purpose of this investigation was to determine the concentration of sodium hypochlorite and the irrigation time required to disinfect dentin cylinders infected with Enterococcus faecalis.Methods: Four hundred fifty dentin cylinders (5 mm in diameter and 4 mm in height) with a lumen (2–3 mm in width) were prepared from freshly extracted bovine incisors. The cementum and predentin were then removed. The tubules were opened by using a 4-minute application with 17% ethylenediaminetetraacetic acid and 5.25% NaOCl and then exposed to E. faecalis (ATCC 4082) for 3 weeks in brain-heart infusion broth. The cylinders were then divided into 3 groups, and a 1.3%, 2.5%, or 5.25% concentration of NaOCl was applied in 5-, 10-, 15-, 20-, 25-, 30-, 35-, and 40-minute intervals for a total of 30 subgroups including positive and negative controls. Each test sample was placed into a tube of 2 mL brain-heart infusion broth and incubated for 72 hours. Absence of turbidity demonstrated no bacterial growth, whereas turbidity indicated presence of remaining viable bacteria.Results: The most effective irrigation regimen was 5.25% at 40 minutes, whereas irrigation with 1.3% and 2.5% NaOCl for this same time interval was ineffective in removing E. faecalis from infected dentin cylinders.Conclusions: High concentration and long exposure to NaOCl are needed for elimination of E. faecalis contaminated dentin.Minimum Contact Time and Concentration of Sodium Hypochlorite Required to Eliminate Enterococcus faecalisBonnie Retamozo, Shahrokh Shabahang, Neal Johnson, Raydolfo M. Aprecio, Mahmoud Torabinejad10.1016/j.joen.2009.12.005Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Technology520523http://www.jendodon.com/article/PIIS0099239909010127/abstract?rss=yesAbstract: Introduction: Mineral trioxide aggregate (MTA), white and gray, has many uses in endodontic therapy but is limited by its difficult handling characteristics. This study compared the physical and chemical properties of white MTA (WMTA) with three experimental root-end filling materials: Capasio (Primus Consulting, Bradenton, FL), Ceramicrete-D (Tulsa Dental Specialties/Argonne National Laboratory, Argonne, IL), and Generex-A (Dentsply Tulsa Dental Specialties, Tulsa, OK).Methods: The setting time and radiopacity were tested using International Organization for Standardization (ISO) 6876 methods. Compressive strength was measured following the ISO 9917 method. The pH of the materials was measured after mixing. A novel test was developed for washout resistance of the materials immediately after placement. Data were compared by analysis of variance and Sidak post hoc analysis (p < 0.05) for compressive strength and washout resistance.Results: The setting time of Generex-A was half that of WMTA. All materials met the ISO 6876 requirements for radiopacity. The compressive strengths after 7 days decreased in this order: Generex-A > Capasio > WMTA > Ceramicrete-D. The initial pH of Capasio and Generex-A were alkaline, similar to WMTA, whereas that of Ceramicrete-D was acidic. Significantly, alternative materials remained in situ after the washout test, whereas WMTA was displaced from the retropreparations.Conclusions: The clinical handling and washout resistance of the alternative materials were far superior to WMTA. The radiopacity, compressive strength, and washout resistance make Generex-A and Capasio materials suitable for further study. Ceramicrete-D was weaker, less radiopaque, and initially acidic.Physical and Chemical Properties of New-generation Endodontic MaterialsMicah L. Porter, Antonio Bertó, Carolyn M. Primus, Ikuya Watanabe10.1016/j.joen.2009.11.012Journal of Endodontics 36, 3 (2010)2010-01-25Journal of Endodontics2010-01-25363S0099-2399(10)X0002-4Technology524528http://www.jendodon.com/article/PIIS009923990900898X/abstract?rss=yesAbstract: Introduction: The objective of this study was to compare the efficiency of 4 ultrasonic tips to remove dentin from sectioned third molars.Methods: The 4 groups (n = 5) were as follows: ET-18D, BUC-1, TUFI-2, and P5. A P5 Newtron XSTM ultrasonic unit was used. A universal tester applied a downward force of 15g, previously determined in a pilot study, in cycles of 20 seconds for a total of 4 minutes of instrumentation time. Efficiency was measured by change in weight of the dentin specimen measured to the nearest 0.01 mg after 2 and 4 minutes of instrumentation.Results: There was no statistically significant difference in dentin removal between measurement times for any tip (P > .05). There was a statistically significant difference in dentin removal as a function of tip type (P = .0001), with the BUC-1 tip removing significantly more dentin across time.Conclusions: On the basis of the results, the BUC-1TM tip removes dentin more efficiently than the other tips tested.Comparison of the Efficiency of Four Different Ultrasonic Tips to Remove Dentin Over TimeChris Yelton, Kerri Lawlor, James C. Kulild, Mary P. Walker10.1016/j.joen.2009.10.024Journal of Endodontics 36, 3 (2010)2010-01-25Journal of Endodontics2010-01-25363S0099-2399(10)X0002-4Technology529531http://www.jendodon.com/article/PIIS0099239909010152/abstract?rss=yesAbstract: Introduction: This study compared three techniques for preparing oval-shaped root canals: Anatomic Endodontic Technology (AET), hand instruments (Hedström files; Dentsply Maillefer, Ballaigues, Switzerland), and rotary nickel-titanium (EndoWave; Morita, Osaka, Japan) instruments with regard to cleaning ability and final canal shape.Methods: Three groups each of 13 extracted human mandibular premolars with oval-shaped canals were used. After canal preparation, teeth were sectioned at three levels (coronal, middle, and apical), photographed to assess cross-sectional canal shape, and processed for histologic evaluation of canal wall planing and the presence of debris.Results: None of the techniques resulted in completely prepared and cleaned canals. No significant difference was found among the three techniques with regard to untouched surface, cross-sectional area, remaining fins, and canal shape at the three levels. Rotary NiTi instruments resulted in significantly less debris in the apical third compared with AET and hand instrumentation.Conclusions: AET did not perform better than rotary NiTi or hand instruments in oval-shaped canals.Comparison of Three Techniques for Preparing Oval-shaped Root CanalsNessrin A. Taha, Toshiko Ozawa, Harold H. Messer10.1016/j.joen.2009.11.015Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Technology532535http://www.jendodon.com/article/PIIS0099239909008802/abstract?rss=yesAbstract: Introduction: An immature tooth with pulpal necrosis and apical periodontitis presents a unique challenge to the endodontist. Endodontic treatment options consist of apexification, apical barriers, or more recently, revascularization. The purpose of this case series is to report three cases that used revascularization protocol as described by Banchs and Trope. Each case presented its own special circumstances and challenges. The lessons learned from each case provided guidance for more predictable outcomes on subsequent cases.Methods: Six immature teeth with apical periodontitis (in three patients) were treated via the revascularization protocol using irrigants, a triple antibiotic paste, and a coronal seal of mineral trioxide aggregate and composite.Results: For follow-up, all six teeth showed resolution of periapical radiolucencies, whereas three of six teeth showed continued root development. Two teeth displayed a positive response to vitality testing.Conclusions: Results from this case series show that revascularization is a technically challenging but effective treatment modality for the immature tooth with apical periodontitis. Based on this case series, the following recommendations are made to help with the revascularization technique: (1) clinicians should consider the use of an anesthetic without a vasoconstrictor when trying to induce bleeding, (2) a collagen matrix is useful for the controlled placement of MTA to a desired and optimal level, (3) patients/parents should be informed about the potential for staining, especially in anterior teeth when the paste contains minocycline, and (4) patient/parent compliance with the necessary multiple appointment treatment plan may be significant for case selection.Challenges in Regenerative Endodontics: A Case SeriesJoseph A. Petrino, Kendra K. Boda, Sandra Shambarger, Walter R. Bowles, Scott B. McClanahan10.1016/j.joen.2009.10.006Journal of Endodontics 36, 3 (2010)2009-12-07Journal of Endodontics2009-12-07363S0099-2399(10)X0002-4Case Report/Clinical Techniques536541http://www.jendodon.com/article/PIIS0099239909009510/abstract?rss=yesAbstract: Introduction: The root canal treatment of a mandibular molar with aberrant canal configuration can be diagnostically and technically challenging.Methods: This case report presents the clinical management of a mandibular first molar with three separate mesial canals including middle mesial canal, which was confirmed by cone-beam computed tomography (CBCT) images.Results: Posttreatment images revealed three independent root canals in the mesial root obturated efficiently to the accepted lengths in all three canals.Conclusion: This case report highlights the usefulness of CBCT imaging for accurate diagnosis and management of the unusual canal morphology.Identification of Independent Middle Mesial Canal in Mandibular First Molar Using Cone-Beam Computed Tomography ImagingSung-Ho La, Dong-Ho Jung, Eun-Cheol Kim, Kyung-San Min10.1016/j.joen.2009.11.008Journal of Endodontics 36, 3 (2010)2010-01-18Journal of Endodontics2010-01-18363S0099-2399(10)X0002-4Case Report/Clinical Techniques542545http://www.jendodon.com/article/PIIS0099239909010279/abstract?rss=yesAbstract: Introduction: Ossifying fibroma mimicking chronic apical periodontitis is extremely rare. This report describes a case of ossifying fibroma located in the periapical region of the mandibular right canine that was misdiagnosed as chronic apical periodontitis.Methods: A 40-year-old woman complained of slight pain in the right anterior mandibular region without mucosal abnormalities or swelling. Radiographically, a well-circumscribed, unilocular, radiolucent lesion was observed that was located in the periapical region of the mandibular right canine, which presented an endodontically treated root canal. Under local anesthesia, the lesion was fully excised.Results: Microscopically, there was fibrocellular connective tissue associated with a mineralized component, which consisted of lamellar or trabecular and woven bone, compatible with the diagnosis of ossifying fibroma.Conclusions: Although it is very rare, ossifying fibroma should be considered in the differential diagnosis of unusual or persistent apical radiolucencies.Ossifying Fibroma Misdiagnosed as Chronic Apical PeriodontitisFlávia Maria de Moraes Ramos-Perez, Ulysses Nicida Soares, Yara Teresinha Corrêa Silva-Sousa, Danyel Elias da Cruz Perez10.1016/j.joen.2009.11.027Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4Case Report/Clinical Techniques546548http://www.jendodon.com/article/PIIS0099239910000907/abstract?rss=yesAbstracts of Research: Schedule of Presentations10.1016/S0099-2399(10)00090-7Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4550550http://www.jendodon.com/article/PIIS0099239910000919/abstract?rss=yesAbstracts10.1016/S0099-2399(10)00091-9Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4551584http://www.jendodon.com/article/PIIS0099239910000920/abstract?rss=yesPresident's Message10.1016/S0099-2399(10)00092-0Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4585585http://www.jendodon.com/article/PIIS0099239910000932/abstract?rss=yesNews10.1016/S0099-2399(10)00093-2Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4586587http://www.jendodon.com/article/PIIS0099239910000944/abstract?rss=yesCall for Submitted Presentations10.1016/S0099-2399(10)00094-4Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4588588http://www.jendodon.com/article/PIIS0099239910000956/abstract?rss=yesAssociate Registry10.1016/S0099-2399(10)00095-6Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4589591http://www.jendodon.com/article/PIIS0099239910000968/abstract?rss=yesCE Registry10.1016/S0099-2399(10)00096-8Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4592592http://www.jendodon.com/article/PIIS009923991000097X/abstract?rss=yesFirst Annual Board Review10.1016/S0099-2399(10)00097-XJournal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4592592http://www.jendodon.com/article/PIIS0099239910000981/abstract?rss=yesSummer Conference 201010.1016/S0099-2399(10)00098-1Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4593593http://www.jendodon.com/article/PIIS0099239910000993/abstract?rss=yesAccess to Apex Education Care10.1016/S0099-2399(10)00099-3Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4593593http://www.jendodon.com/article/PIIS0099239910000816/abstract?rss=yesEditorial Board10.1016/S0099-2399(10)00081-6Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4FrontmatterA2A2http://www.jendodon.com/article/PIIS0099239910000828/abstract?rss=yesTable of Contents10.1016/S0099-2399(10)00082-8Journal of Endodontics 36, 3 (2010)2010-03-01Journal of Endodontics2010-03-01363S0099-2399(10)X0002-4FrontmatterA5A5