Endodontics

Introduction-Eliminating and/or inhibiting bacterial growth within the root canal system have been shown to play a key role in the regenerative outcome. The aim of this study was to synthesize and determine in vitro both the antimicrobial effectiveness and cytocompatibility of bi-mix antibiotic-containing polydioxanone (PDS)-based polymer scaffolds. Methods-Antibiotic-containing (metronidazole, MET and ciprofloxacin, CIP) polymer solutions (distinct antibiotic weight ratios) were spun into fibers as a potential mimic to the double antibiotic paste (DAP, a MET/CIP mixture). Fiber morphology, chemical characteristics, and tensile strength were evaluated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and tensile testing, respectively. Antimicrobial efficacy was tested over time (aliquot collection) against Enterococcus faecalis (Ef), Porphyromonas gingivalis (Pg), and Fusobacterium nucleatum (Fn). Similarly, cytotoxicity was evaluated in human dental pulp stem cells (hDPSCs). Data were statistically analyzed (p<0.05). Results-SEM and FTIR confirmed that electrospinning was able to produce antibioticcontaining fibers with diameter mostly in the nanoscale. Tensile strength of 1:1MET/CIP scaffolds was significantly (p<0.05) higher than pure PDS (control). Meanwhile, all other groups presented similar strength as the control. Aliquots obtained from antibiotic-containing scaffolds inhibited growth of Ef, Pg and Fn, except pure MET that did not show an inhibitory action towards Pg or Fn. Antibiotic-containing aliquots promoted slight hDPSCs viability reduction, but none of them were considered to be cytotoxic.

Introduction: Diagnostic terminology used in endodontics has been based on historical use, textbook and glossary terms, best-available science, and personal conviction. There is minimal evidence that establishes an absolute set of terms that can be used to make a definitive diagnosis. As a component of the Consensus Conference on Diagnostic Terminology held in October 2008, an online survey was conducted to invitees to assess their opinions on diagnosis. Methods: Thirty-six questions were developed by the oversight committee and chairs of the subcommittees. Most questions used a modified Likert scale to generate a response. At least a 51% agreement or disagreement to the statement was considered a consensus, and a response greater than 25% but less than 51% generated a minority report. Results: Thirtyone of the 36 questions were designed to determine consensus. All 31 generated a consensus response, with 14 of those generating a minority report. Minority reports suggest that there was still greater than 25% of the respondents who did not follow consensus. Possible explanations were provided for those statements that generated a minority report. Conclusions: Data from the online survey provided trends and preferences toward particular diagnostic terms and beliefs. The limitations of such a survey are multiple including the limited size and nature of the respondent group, responses based on opinion, and question design. The online survey results suggest an awareness for the specialty to develop better diagnostic tools and terminology that are biologically and metric based.

Introduction: Consensus Conference Subcommittee 2 was charged with the identification and definition of all diagnostic terms for pulpal health and disease states by using a systematic review of the literature. Methods: Eight databases were searched, and numerous widely recognized endodontic texts were consulted. For each reference the level of evidence was determined, and the findings were summarized by members of the subcommittee. Highest levels of evidence were always included when available. Areas of inquiry included quantification of pulpal pain, the designation of conditions that can be identified in the dental pulp, diagnostic terms that can best represent pulpal health and disease, and metrics used to arrive at such designations. Results and Conclusions: On the basis of the findings of this inquiry, specific diagnostic terms for pulpal health and disease are suggested. In addition, numerous areas for further study were identified. (J Endod 2009;35:1645-1657 A n evidence-based practice centers on the integration of the best clinically relevant scientific information with the patient's desires and the individual practitioner's clinical practice abilities. Its ultimate goal is to enhance patient care through the development of appropriate treatment modalities for specific clinical presentations. The development of standard terminology is at the center of patient care in that it facilitates communication between the patient and doctor as well as between dental health professionals. Presently in endodontics there is no standard diagnostic nomenclature consensus for pulpal status in health or disease. The objective of this analysis was the establishment of evidencebased diagnostic nomenclature for clinically encountered pulpal conditions.

The purpose of this paper was to study the reaction of rat subcutaneous connective tissue to the implantation of dentin tubes filled with white mineral trioxide aggregate (MTA), a material that will be marketed. The tubes were implanted into rat subcutaneous tissue and the animals were sacrificed after 7 and 30 days. The undecalcified pieces were prepared for histological analysis with polarized light and von Kossa technique for mineralized tissues. Granulations birefringent to polarized light and an irregular structure like a bridge were observed next to the material; both were von Kossa positive. Also, in the dentin wall tubules a layer of birefringent granulations was observed. The results were similar to those reported for gray MTA, indicating that the mechanisms of action of the white and gray MTA are similar.

Introduction: There is evidence to suggest that an association exists between oral infections and coronary heart disease (CHD). Subjects presenting lesions of endodontic origin (LEOs) or pulpal inflammation had an increased risk of developing CHD. However, findings concerning systemic manifestations of apical periodontitis (AP) remain controversial. An association between CD14 gene polymorphisms and atherosclerosisassociated diseases has been shown, but there are no data regarding an association between CD14 polymorphism and AP. This study evaluated associations between clinical oral health status, CD14 polymorphisms, and CHD. Methods: A case-controlled clinical trial was designed to compare middle-aged adults with acute myocardial infarction or unstable angina (n = 51) within 12 months of the acute event defined as first manifestation with healthy controls (n = 49). Participants were matched for age, sex, and socioeconomic status. Indicators of oral disease and compliance were evaluated. CD14 polymorphisms were analyzed by restriction fragment length polymorphism-polymerase chain reaction. Results: CHD subjects had a higher prevalence of oral diseases and lower compliance to oral preventive strategies than healthy controls. Multivariate analysis showed a positive association between missing teeth (odds ratio [OR] = 1.37; 95% confidence interval [CI], 1.02-1.85), the number of LEOs (OR = 4.37; 95% CI, 1.69-11.28), chronic periodontitis (OR = 5.87; 95% CI, 1.17-29.4), and CHD. No statistically significant association emerged between the CD14 C(À260)T and the CD14 C(À159)T polymorphism, endodontic or periodontal disease, and CHD. Conclusions: Chronic oral diseases may increase the risk of CHD and may be an unconventional risk factor for CHD. (J Endod 2012;38:1570-1577

We aimed to compare the apical sealing ability of two experimental retrograde root-filling cements and mineral trioxide aggregate using a fluid filtration method. X-ray diffraction (XRD) and X-ray fluorescence spectrometry (XRF) were used to evaluate structural and qualitative characteristics. Thirty single-rooted extracted teeth were treated, root-end prepared, and obturated using MTA and two experimental cements. Fluid filtration was measured during a 5-minute period after 4, 24, and 48 hours and 1, 2, and 12 weeks. The results were statistically compared by using a two-way analysis of variance (p Ͻ 0.05). The marginal adaptation was evaluated by using a SEM replica technique. XRD analyses showed similar patterns. XRF showed lower amounts of SiO 2 and FeO 3 in the experimental cements. All cements showed a reduced fluid flow rate over time. No significant differences were found between the cements. The SEM replica indicated a good marginal adaptation to dentinal walls. Both experimental cements showed suitable properties as retrograde rootfilling materials. (J Endod 2007;33:742-745)

The identification and interpretation of periapical bony lesions is important for accurate diagnosis and treatment. Diagnostic accuracy may depend on the extent of bony involvement of the lesion as well as on the type of diagnostic imaging system used. A recent advance in imaging technology is direct digital imaging (DDI). The standard DDI system uses a sensor containing a charge-coupled device (CCD) that produces an image as an array of pixels displayed on a computer monitor. The computerized image can be manipulated and enhanced with computer software. Advantages of DDI include a 50% reduction in radiation exposure, 1 immediate image generation, image manipulation, elimination of chemical processing of radiographs, and enhancement of one's ability to educate patients.

Root canal samples, taken from periapical tissue exudates during routine root canal treatment procedures, were processed for identification of tumor necrosis factor using a mouse anti-human monoclonal antibody and enzyme-linked immunosorbent assay. Detectable levels of tumor necrosis factor were identified in periapical tissue exudates in chronic apical periodontitis.

Introduction: The present in vitro study was conducted with the aim of evaluating and comparing the cytotoxic effects of three root-end filling materials, Pro-Root mineral trioxide aggregate (ProRoot MTA; Dentsply Tulsa Dental, Memphis, TN), MTA Angelus (Angelus, Londrina, Brazil), and a modified zinc oxideeugenol cement (Super-EBA; Bosworth Co, Skokie, IL) on human periodontal ligament (PDL) fibroblasts. Methods: PDL cells were cultured in an mineral trioxide aggregate (MTA)-or a Super-EBA-conditioned medium to assess the viability as determined by the trypan blue exclusion assay. The proliferation of the cells was recorded, and the cellular morphology was observed by confocal microscopy. Moreover, PDL cell aggregates were cultured on the substrate surfaces to assess cell adhesion. Results: ProRoot MTA was found to be the most biocompatible material, whereas Super-EBA was found to be the most cytotoxic material because it significantly inhibited the cell growth and adherence on its. In the presence of ProRoot MTA, the PDL cell proliferation was almost unaltered. MTA Angelus was found to be more cytotoxic than ProRoot MTA, offering, however, excellent scaffold properties for the adhesion of cell aggregates. Conclusions: Under the conditions of the present study, it seems that commercially available forms of MTA may behave in different ways regarding their proliferative effect on human PDL fibroblasts. ProRoot MTA appears to be the most biocompatible of the three tested materials when considering use for root-end endodontic microsurgery.

A mandibular first molar with more than four canals is an interesting example of anatomic variations, especially when four of these canals are located in distal roots. This report describes a case of a mandibular first molar with six canals (two mesial and four distal canals in two distal roots). The canals were equipped with a K-file and irrigated with NaOCl (5.25%) and normal saline as the final irrigant. The canals were filled laterally with gutta percha and AH26 sealer (De Trey, Dentsply, Switzerland). This case shows a rare anatomic configuration and points out the importance of looking for additional canals.

This study was conducted to observe the rat subcutaneous connective tissue reaction to implanted dentin tubes that were filled with mineral trioxide aggregate, Sealapex, Calciobiotic Root Canal Sealer (CRCS), Sealer 26, and the experimental material, Sealer Plus. The animals were sacrificed after 7 and 30 days, and the specimens were prepared for histological analysis after serial sections with a hard-tissue microtome. The undecalcified sections were examined with polarized light after staining according to the Von Kossa technique for calcium. At the tube openings, there were Von Kossa-positive granules that were birefringent to polarized light. Next to these granulations, there was irregular tissue, like a bridge, that was Von Kossa-positive. The dentin walls of the tubes exhibited a structure highly birefringent to polarized light, usually like a layer, in the tubules. These results were observed with all the studied materials, except the CRCS, which didn&#39;t exhibit any kind of...

IntroductionObtaining hemostasis in the surgical crypt during periradicular surgery is essential. It allows for improved visibility and contributes to a dry environment suitable for the placement of moisture-sensitive root-end filling material. Although current materials may not be moisture sensitive during setting, hemostasis is important for proper placement of root-end filling materials during apical surgery. A new hemostatic agent, HemCon dental

Up-to-date studies comparing endodontic treatment versus implant-supported prosthesis have shown similar clinical outcome and survival rates. However, no data are available comparing both treatment modalities based on the patient's perception of quality of life. This study was designed to qualitatively describe and compare the quality of life of patients with restored, single endodontically treated teeth versus patients with single implant-supported fixed prostheses. Methods: Forty-eight patients agreed to participate in the study (n = 24 from each treatment modality). Of those, 37 actually participated in the study: 17 were endodontically treated and 20 had an implantsupported prosthesis. Patients in each of the two groups were randomly selected from the Graduate Endodontics and Graduate Periodontics Departments, respectively. Six focus group discussions (n = 3 per treatment group) were held and audio-recorded for subsequent thematic analysis. Data were analyzed to identify common themes within each category and compared to assess any differences in quality of life between the two treatments. Additionally, a quality of life survey, the shortened version of the Oral Health Impact Profile (OHIP-14), was given before the discussion group and the responses analyzed. Results: The results obtained from this study show similar overall OHIP scores and show a high rate of satisfaction with both treatment modalities. Content analysis of the discussion groups revealed several themes and subthemes. The major themes were importance of overall health, financial implications of the treatments, perception of the treatments and its outcomes, time since treatment, and follow-up dental visits. Conclusions: The results help identify patients' perception and concerns with each treatment modality and assist the clinician and patient in the selection of an optimal treatment for their given situation. In addition to the prognosis and outcomes, clinicians should consider patients' perceptions and preferences as well as the influence each therapy may have on their quality of life, both short-and long-term. Overall, all the participants in this study were pleased with the treatment received and expressed a clear message to save their natural dentition whenever possible. (J Endod 2011;37:903-909)

Studies conducted in Iran indicated dissatisfaction of many students of dentistry in acquiring sufficient skill to carry out therapeutical procedures. The present study was aimed to analyze the effect of short lectures on promoting the knowledge of interns in Endodontic course. In this quasi-experimental study, the knowledge and skill of the experimental group (teaching via short lectures) and control group (traditional teaching method) were compared in Endodontic course. Totally 20 students were included in each experimental and control group. Data were collected by a questionnaire consisting of two sections: demographic information and self-evaluation of the endodontics' knowledge and skill (30 questions). The means of scores in the pre-test and pot-test in control group were 99±11.2 and 102±11.7, respectively (P=0.13) and the means of scores in experimental group were 100±9.4 and 119±13.7 indicating a significant difference (P<0.05). Short lecture as a simple, inexpensive and less time-consuming method is an efficient method to promote the knowledge in Endodontic course.

The demand for aesthetic restoration is a key factor in the placement and popularity of direct composites. New technologies have been implemented over a period of time in the shade matching of composites, which is more reliable than the conventional approach to date. Difficulty with rapidly evolving technologies and inflationary pressure due to increased costs can be the reason why most practitioners use the Vita classic shade guide as traditional method. These traditional shade guides are often manufactured according to the properties of porcelain materials rather than composite resin options.
Aim: This article compares the color difference (ΔE) between Vita classic shade tab and customized composite shade tab using spectophotometric analysis for predictable shade matching in direct composite restorations.
Materials and Methods: In order to compare the customized composite shade tab (A1 and A2) with the regular Vita classic shade tab (A1 and A2), five A1 and A2 shade tabs were fabricated from two separate composite brands (AmelogenTM Plus-ULTRADENT, Coltene Brilliant) in order to obtain a total of twenty samples (n=5 each). The fabrication of the customized shade tabs was done using Smile line Style Italiano mini guide kit. All the twenty samples, (customized composite A1, A2 shade tabs) and the Vita classic A1 and A2 shade tab were subjected to spectrophotometric analysis using Data color 650 sphectrophotometer to measure the CIE-Lab values. Based on CIE-Lab parameters obtained from computerized spectrophotometry digital reading of A1, A2 customized composite shade tab and A1, A2 Vita classic shade tabs, the Euclidean distance (ΔE) between two color points (composite-Vita classic) was calculated for the determination of color differences.
Conclusion: There was a perceptible color difference between the most commonly used Vita classic shade tab and the customized shade tab. Therefore, shade matching in direct composite restoration requires customized composite shade tabs to achieve predictable results.
Keywords: Shade guide, Spectrophotomter, Shade matching, Customized composite shade tab.

A new circuit was designed to automatically compensate for measurement errors of an electronic apex locator in various electrolytes. Thirty-one root canals were clinically tested for accuracy. A file was inserted into the canal until the apex signal was obtained, at which point the file was immobilized with glass-ionomer cement. After extraction, the apical area was exposed and the position of the file tip was examined under an operating microscope. Distances from the major foramen and cemento dentinal junction (CDJ) were recorded. The average distance from the major foramen was -0.13 mm with a range of -1.28 mm and +0.46 mm. The average distance in 26 detectable CDJ samples was +0.18 mm with a range of -0.98 mm and +0.65 mm. The measurements, which were within +/- 0.5 mm, were 94% (29/31) from the major foramen and 92% (24/26) from the CDJ. Measurement consistencies within one SD were 81% for the major foramen and 65% for the CDJ, respectively. Measurements within two SD were 97% f...

Introduction: Vocabulary and writing style have been shown to affect the readability of patient-education materials. Readability is generally defined as the ease of understanding or comprehension because of the style of writing. Microsoft Word software (Microsoft Corporation, Bellevue, WA) can quantify and report readability statistics, providing both the Flesch Reading Ease score and the Flesch-Kincaid Grade Level score of selected documents. Methods: This study evaluated the readability of 22 endodontic patient education web sites and 15 endodontic patient education brochures. The web sites and brochures were arbitrarily selected based on availability, reputation of the source, and relevance to endodontic patients. Results: The Flesch Reading Ease score and the Flesch-Kincaid Grade Level score were determined for the 37 selected materials. The Flesch Reading Ease scores varied between 44.4 and 76.6, and the Flesch-Kincaid Grade Level scores ranged between 4.5 and 10.6. Conclusions: These findings remind practitioners that some patients may have difficulty reading some endodontic educational materials. (J Endod 2010;36:1703-1706

Introduction: Enterococcus faecalis is a member of the mammalian gastrointestinal microbiota but has been considered a leading cause of hospital-acquired infections. In the oral cavity, it is commonly detected from root canals of teeth with failed endodontic treatment. However, little is known about the virulence and genetic relatedness among E. faecalis isolates from different clinical sources. This study compared the presence of enterococcal virulence factors among root canal strains and clinical isolates from hospitalized patients to identify virulent clusters of E. faecalis. Methods: Multilocus sequence typing analysis was used to determine genetic lineages of 40 E. faecalis clinical isolates from different sources. Virulence clusters were determined by evaluating capsule (cps) locus polymorphisms, pathogenicity island gene content, and antibiotic resistance genes by polymerase chain reaction. Results: The clinical isolates from hospitalized patients formed a phylogenetically separate group and were mostly grouped in the clonal complex 2, which is a known virulent cluster of E. faecalis that has caused infection outbreaks globally. The clonal complex 2 group comprised capsule-producing strains harboring multiple antibiotic resistance and pathogenicity island genes. On the other hand, the endodontic isolates were more diverse and harbored few virulence and antibiotic resistance genes. In particular, although more closely related to isolates from hospitalized patients, capsuleproducing E. faecalis strains from root canals did not carry more virulence/antibiotic genes than other endodontic isolates. Conclusions: E. faecalis isolates from endodontic infections have a genetic and virulence profile different from pathogenic clusters of hospitalized patients' isolates, which is most likely due to niche specialization conferred mainly by variable regions in the genome. (J Endod 2013;39:858-864)

The purpose of this study was to determine the effect of one dose of a common narcotic-based pain reliever (Vicodin) on a battery of oral sensitivity tests across time in women. Fifteen Caucasian women randomly were given an oral dose of 10 mg of hydrocodone/1000 mg of acetaminophen or placebo in a double-blind, cross-over design. At baseline (before drug) and after 2, 4, and 8 h each subject was evaluated for sensitivity thresholds with four tests around an experimental tooth: (a) electric pulp tester applied to exposed root; (b) electric pulp tester on adjacent mucosa; (c) increasing probe pressure (grams) on adjacent mucosa; and (d) decreasing cold probe (°C) on the exposed root. The outcomes of all tests were not statistically different between drug and placebo treatments at any time point (p > 0.05). These results suggest that a systemic dose of hydrocodone/acetaminophen has little impact on healthy pulp or mucosa sensitivity in women as measured by common diagnostic tests.

Huntington's disease is a lethal autosomal dominant disorder that affects men and women equally. The prevalence of Huntington's disease in North America is 5 to 10 per 100,000 people. It is characterized by regular personality changes, dementia, and choreiform (dance-like) movements. Literature concerning dental treatment of patients who have been diagnosed with this type of disease is scarce. Continuous ingestion of medications to control the symptoms of this disease leads to xerostomia, which, maximized by unrestrained movements, often leads to progressive tooth decay, irreversible pulpitis, and tooth loss. Maintenance of teeth in patients with this type of disease is desirable and challenging. Like any patient, a comprehensive treatment plan needs to be developed with equal emphasis on restoration and home care. This case report illustrates how a morphologically difficult endodontic procedure can be successfully administered in a patient diagnosed with HD. Overall case success was attributed to a dental team approach and short-duration appointments to limit patient stress.

The purpose of this research was to investigate whether calcium ions from a paste of calcium hydroxide [Ca(OH)2] and saline introduced into root canals diffuse through the dentin to reach the surface of the root. Six teeth were opened and submitted to a biomechanical process, after which all the smear layer was removed. The experiment was divided into three phases: dissolution, dissolution and diffusion I, and dissolution and diffusion I1.

This study compared the difference in decision making regarding retreatment of endodontically treated teeth by general dental practitioners and endodontists. Thirty radiographs of endodontically treated teeth taken from undergraduate records with their respective case descriptions were submitted to fifteen endodontists and fifteen general dental practitioners. Seven treatment alternatives were given as choices; reasons for retreatment, if chosen, were also requested and presented as choices. The results showed statistically different decisions among these two groups regarding retreatment cases. More endodontists opted for retreatment of cases, while higher percentages of general dentists decided to observe, not treat or extract. To prevent misdiagnosis and eventually mistreatment, endodontic decision making should be taught. Currently, there are no specific guidelines for management of failed root canal retreatment. It is suggested that guidelines generated by evidence-based dentistry may produce less variation in clinical decision making.

Root canal morphology changes during canal preparation, and these changes may vary depending on the technique used. Such changes have been studied in vitro by measuring cross-sections of canals before and after preparation. This current study used nondestructive high-resolution scanning tomography to assess changes in the canals' paths after preparation. A microcomputed tomography scanner (cubic resolution 34 m) was used to analyze 18 canals in 6 extracted maxillary molars. Canals were scanned before and after preparation using either K-Files, Lightspeed, or ProFile .04 rotary instruments. A special mounting device enabled precise repositioning and scanning of the specimens after preparation. Differences in surface area (⌬A in mm 2 ) and volume (⌬V in mm 3 ) of each canal before and after preparation were calculated using custom-made software. ⌬V ranged from 0.64 to 2.86, with a mean of 1.61 ؎ 0.7, whereas ⌬A varied from 0.72 to 9.66, with a mean of 4.16 ؎ 2.63. Mean ⌬V and ⌬A for the K-File, ProFile, and Lightspeed groups were 1.28 ؎ 0.57 and 2.58 ؎ 1.83; 1.79 ؎ 0.66 and 4.86 ؎ 2.53; and 1.81 ؎ 0.57 and 5.31 ؎ 2.98, respectively. Canal anatomy and the effects of preparation were further analyzed using the Structure Model Index and the Transportation of Centers of Mass. Under the conditions of this study variations in canal geometry before preparation had more influence on the changes during preparation than the techniques themselves. Consequently studies comparing the effects of root canal instruments on canal anatomy should also consider details of the preoperative canal geometry.

Dental trauma can lead to injuries in teeth and their supporting structures, which occurs most commonly in young patients and varies in severity from enamel fractures to avulsions. Root fractures are relatively uncommon among dental traumas, mostly affecting the permanent dentition. It has been reported that root fractures can undergo healing, whereas pulp necrosis can also occur.In this report, we present a case of the utilization of cone-beam computed tomography (CBCT) in the detection of possible cervical or internal resorption secondary to a mid-horizontal fracture in a 36-year-old male patient. The fractured teeth spontaneously healed and were diagnosed radiographically after 28 years. Initially, conventional radiographs showed fractured fragments with radiolucent lines. Because of possible invasive cervical resorption and doubt over internal resorption in the conventional images, it was decided to examine the teeth with cone-beam computed tomography with three-dimensional reconstructions.The images clearly showed the displaced fragments of the root fracture. Despite the appearance in the conventional radiograph, no evidence of cervical or internal resorption was detected in the teeth other than the healed root fracture.It was concluded that CBCT images should be obtained for root fractures, especially those in which cervical or internal resorption is suspected from routine conventional radiographs.

A radiographic recall evaluation of 894 endodontic cases treated by dental students at the University of Oklahoma College of Dentistry was conducted by faculty. The purpose of this study was to determine the success of standardized nonsurgical endodontic treatments by using radiographic techniques of determination and to compare the results to similar studies at other dental schools. Cases were labeled as successful, acceptable, questionable, and failing. Observations included time since treatment, age, gender, and tooth type. The combined percentage of successful and acceptable cases was 91.05%. Differences in percentage of success among recall time intervals were statistically significant (p &lt; 0.01), as were the percentages of success between tooth types treated (p &lt; 0.05). Success rate was not affected by age or gender (p &gt; 0.05). The overall rate of successful and acceptable cases in this study was found to compare favorably with those from recall studies conducted at o...

ABSTRACT : The root canal system is an arborizational, anastomotic, byzanthine, labyrinthine complexity, morphologically comparable to a mosaic. While primary canals exist, the tributaries, accessory branches and lumina of dentinal tubules harbour extensive tissue and microflora which if left untreated remains vector for persistent and refractory pathology. Therefore root canal  shaping and cleaning is of utmost importance in the success of root canal treatment. Number of systems are available for effective shaping accounting from hand files to nickel titanium rotary files to the new single file concept “WAVE ONE” KEYWORDS : Wave One, Reciprocating Motion, Nickel Titanium, Reverse  Balanced Force Technique, vCJD
| Dr VINEET VINAYAK| Dr VINEET VINAYAK|dr VINEET vinayak

This second update paper aims to provide a review of changes and developments that have occurred within the fi eld of pulp therapy for primary teeth since the publication of the BDJ's series and textbook A clinical guide to endodontics. The biological basis of pulp therapy is an area where much recent research has taken place, particularly linked to the healing capacity of pulp tissue. This has lead to the adoption of treatment techniques aimed at maintaining pulp vitality. Such techniques are introduced here as a more contemporary, biological approach to pulp management in the primary dentition.

The aim of this study was to evaluate the persistence of methacrylate-based cement residues on the dentin, after dentin surface cleaning with ethanol or acetone, with or without previous application of a dentin adhesive. Forty bovine crown fragments were obtained and the dentin surface was washed with 1.0 mL of 2.5% sodium hypochlorite (NaOCl), followed by 0.1 mL of 17% ethylenediaminetetraacetic acid application for 3 min, and final irrigation with 2.5% NaOCl. The specimens were air dried and resin-based cement was rubbed onto the dentine surface with a microbrush applicator. In 20 specimens, previously to cement, a dentin adhesive was applied in all surfaces. After 15 min, the surface was scrubbed with a cotton pellet and moistened with ethanol or acetone, compounding the following groups: G1-99.5% ethanol and G2-acetone, without previous use of dentin adhesive; G3-99.5% ethanol and G4-acetone, with previous use of dentin adhesive. The dentin surface was scrubbed until the cement residues could not be visually detected. Sections were then processed for scanning electron microscopy and evaluated at 5003 magnification and scores were attributed to each image according to the area covered by residual sealer, and data were subjected to Kruskal-Wallis at 5% significance. The lower residue presence was observed in G3 (P 5 0.005). All surface presented cement residues when acetone was used as cleaning solution (P 5 0.0005). The cleaning solutions were unable to completely remove the cement residues from both surfaces. The ethanol used after previous application of the dentin adhesive promoted the lower presence of residues.

Root thickness in the mesial canals of lower first and second molars was compared before and after flaring by using a muffle system. Gates Glidden burs or M-Series Canal Openers were used with either a straight up-and-down motion or with an anticurvature motion. It was found that Gates Glidden burs used straight up and down removed statistically more dentin at the level of the furcation than Canal Openers used straight up and down or in an anticurvature fashion. At a level 2 mm apical to the furcation, Gates Glidden burs used in an anticurvature fashion removed statistically more dentin than any other method tested.

Eighty freshly extracted teeth were endodontically prepared and filled with gutta-percha and either a zinc oxide-eugenol-based sealer or AH26 to determine what effect these sealers, with widely differing properties, would have on apical microleakage after either immediate or delayed dowel space preparation. The teeth were randomly assigned to 1 of 4 groups, and the post space was made either immediately after filling or after being stored in 100% humidity for 1 wk. They were then immersed in a 2% methylene blue solution under vacuum, washed, and split longitudinally. The extent of dye penetration was read by five independent observers and the results analyzed. The only significant difference was in the delayed preparation group with zinc oxide-eugenol sealer, which showed greater leakage than the other groups.

Closed root canals likely have an oxygen-free environment; most bacteria in canals are anaerobic. These bacteria and other debris are difficult to remove. Unknown is tissue dissolution with chemicals under these anaerobic conditions. This study evaluated and compared dissolving properties of calcium hydroxide (Ca(OH)2) and sodium hypochlorite (NaOCI) on bovine pulp tissue in aerobic and anaerobic environments. Sixty bovine pulp specimens were dried, then randomly divided into six groups. Groups A and B were immersed in Ca(OH)2 + water solution, whereas group C and D were in 2.5% NaOCI. Groups E and F (controls) specimens were placed in distilled water. Groups A, C, and E were incubated anaerobically, and groups B, D, and F were incubated under regular atmospheric conditions, all for 7 days. Percentages of weight loss were compared between groups. Results showed the following: (a) both chemicals partially dissolved pulp tissue, (b) anaerobic environment did not alter tissue-dissolving properties of Ca(OH)2 or NaOCI, and (c) Ca(OH)2 and NaOCI were equal and more effective than water.

Pulpitis, external root resorption, and pain may be experienced during orthodontic movement. The use of nonsteroidal anti-inflammatory drugs (NSAIDs) has been suggested to control these changes. The purpose of this study was to observe pulp-dentinal reactions, root resorption, tooth pain, and tooth movement after the application of a 4-ounce intrusive orthodontic force to human maxillary first premolars in patients given the NSAID nabumetone. Thirty-four maxillary first premolars were evaluated. A placebo was prescribed to 17 patients after an intrusive force was activated and reactivated for an 8-week period on the right side. The same procedure was repeated on the left side after patients were given nabumetone. Pulp-dentinal reactions and external root resorption were evaluated by histology. Pain and movement were also evaluated. Nabumetone was found to be useful in reducing pulpitis, external root resorption, and pain caused by intrusive orthodontic movement, without altering tooth movement in response to the application of orthodontic force.

Introduction: Endodontic-periodontal combined lesion is a clinical dilemma because making a differential diagnosis and deciding a prognosis are difficult. Methods: Twenty-six cases from 14 articles involving the successful management of endodontic-periodontal lesions with concurrent regenerative procedures were reviewed. This article also presents successful treatment of an endodontic-periodontal combined lesion involving a grade II mesial furcation of a maxillary molar with root canal treatment and multiple regenerative procedures. Results: A treatment algorithm is outlined for the application of the guided tissue regeneration (GTR) in managing endodontic-periodontal combined lesion. This treatment algorithm consists of 4 phases: (1) presurgical phase (determining periodontal/regenerative prognosis), (2) endodontic phase, (3) periodontal surgical phase, and (4) post-GTR reevaluation protocol. Conclusions: The proposed 4-phase treatment algorithm might provide a beneficial guideline in managing the endodontic-periodontal combined lesions.

The cutaneous sinus tract of dental origin is an uncommon but well documented condition. Its diagnosis is not always easy unless the treating clinician considers the possibility of its dental origin. Such patients may undergo multiple surgical excisions, biopsies, and antibiotic regimens, but all of them fail with the recurrence of the sinus tract. This is because the primary etiology is incorrectly diagnosed. This case report describes the treatment of four patients presenting with variable complaints of pain and purulent or hemorrhagic discharge from lesions of the face. Clinical and radiographic examination revealed carious teeth with radiolucent areas indicating chronic periradicular abscess. The teeth were restorable, so nonsurgical endodontic therapy was performed in all of them. No systemic antibiotic therapy was provided. The patients responded well, and the cutaneous lesions healed uneventfully. Improper diagnosis can lead to needless loss of teeth that can be otherwise maintained through timely and proper management.

Introduction: The aim of this study was to investigate the effect of different concentrations of cetrimide with or without 5% EDTA solution on the microhardness of human root dentin in vitro. Methods: Twenty-five recently extracted single-rooted human teeth were selected. The roots were split longitudinally into 2 parts. The specimens were randomly divided into the following 5 groups and were treated with 5% EDTA, 5% EDTA + 0.25% cetrimide, 5% EDTA + 0.50% cetrimide, 0.25% cetrimide, and 0.50% cetrimide immediately after the initial baseline microhardness measurements. A standardized volume of 50 mL of each solution was used for 1 minute. The reference microhardness values of untreated specimens were initially measured with a Vickers indenter under a 50-g load and a 10-second dwell time at the midroot level of the root dentin. Posttreatment microhardness values were obtained in the same manner as the initial ones. The decrease in microhardness was calculated as a percentage. Data were analyzed statistically by 1-way analysis of variance (P = .05) and the post hoc Tukey test for multiple comparisons at the same level of significance. Results: All solutions significantly decreased the microhardness of root dentin (P < .05). Although there was no significant difference among the solutions (P > .05), the specimens in the EDTA + 0.50% cetrimide solution group showed the highest change in microhardness. The plain EDTA and plain 0.50% cetrimide groups had similar values. Conclusions: The use of surfactants higher than 0.25% in concentration is questionable for clinical conditions. (J Endod 2012;38:704-707)

The purpose of the present study was to assess the effect of the presence of surfactants over time on free available chlorine (FAC), pH, viscosity, and surface tension of sodium hypochlorite (NaOCl) preparations. Three preparations containing surfactant (Chlor-XTRA 6% [Vista Dental Products, Racine, WI], Hypocelle 4% Forte [Dentalife, Ringwood, Australia], and White King Lemon [Pental, Shepparton, Australia]) and 2 without, Vista 6% (Vista Dental Products) and Hypocelle 4% Forte plain (Dentalife), were tested. The solutions were stored in closed plastic bottles and protected from light at a constant 20°C for 213 days. FAC was measured using iodometric titration, whereas pH, surface tension, and viscosity were measured using a pH meter, pendant drop method, and rheometer, respectively. The influence of the type of solution and the presence of surfactant over time on FAC was compared with the aid of linear regression models. Two-way analysis of variance was used to evaluate the effect...

Severe pain and/or swelling following a root canal treatment appointment are serious sequelae. Information varies or is incomplete as to the incidence of these conditions and related factors. In this study, data were collected at root canal treatment appointments on demographics, pulp/periapical diagnoses, presenting symptoms, treatment procedures, and number of appointments. Patients that then experienced a flare-up (a severe problem requiring an unscheduled visit and treatment) had the correlating factors examined. Statistical determinations were by chi-square analysis with significance at 0.05 or less. Nine hundred forty-six visits resulted in an incidence of 3.17% flare-ups. Flare-ups were positively correlated with more severe presenting symptoms, pulp necrosis with painful apical pathosis, and patients on analgesics. Fewer flare-ups occurred in undergraduate patients and following obturation procedures. There was no correlation between patient demographics or systemic conditio...

Introduction: The purpose of this study was to quantitatively analyze the effects of different concentrations and exposure times of sodium hypochlorite (NaOCl) on dentin deproteination and to determine the suitable concentrations and exposure times to minimize the effects of deproteination on dentin. Methods: Intact human dentin slabs were treated with 0.5%, 1%, or 2.25% NaOCl for 1, 5, or 10 minutes. A 0.9% NaCl solution served as the control. To investigate the effect of NaOCl on the surface chemical changes to human dentin, the attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy technique was used to analyze the amide:phosphate ratio and carbonate:phosphate ratio. Results: The amide:phosphate ratio decreased significantly after NaOCl treatment as compared with the control group (p < 0.05). In the 0.5% NaOCl treatment group, the amide:phosphate ratio was significantly higher than that in the 1% and the 2.25% NaOCl treatment groups (p < 0.05). The different exposure times (1, 5, or 10 minutes) of NaOCl within the same concentration did not influence the amide:phosphate ratio (p > 0.05). NaOCl treatment did not affect the carbonate:phosphate ratio (p > 0.05). Conclusions: NaOCl, 0.5%, is recommended as the predominant concentration for routine use during root canal therapy to minimize any NaOCl-induced dentin deproteination. It is suggested that a prolonged exposure to low concentrations of NaOCl is less damaging to dentin in attempting to achieve antisepsis during instrumentation of root canal therapy. (J Endod 2010;36: 2008-2011

ProFile nickel-titanium Gates Glidden drills were tested in bending fatigue to simulate clinical conditions. Ten samples each in sizes #1 through #6 were placed in a device that deflected the drill head 4 mm from the axis. The drill head was placed inside a ball bearing fixture, which allowed it to run free at 4000 rpm, and the total number of revolutions was recorded until failure. Fracture surfaces were examined with a scanning electron microscope to determine the initiation site and nature of the failure process. Mean Ϯ SD for the number of revolutions to failure for the drill sizes were: #1: 1826.3 Ϯ 542.5; #2: 5395.7 Ϯ 2581.5; #3: 694.4 Ϯ 516.8; #4: 261.0 Ϯ 138.0; #5: 49.6 Ϯ 14.9; #6: 195.9 Ϯ 78.5. All drills failed in a ductile mode, and fracture initiation sites appeared to be coincident with machining grooves or other flaws, suggesting the need for improved manufacturing procedures.