Comparative effectiveness of preemptive administration of ibuprofen and ibuprofen-arginine on the anesthetic success of inferior alveolar nerve block in teeth with symptomatic irreversible pulpitis - A double-blind randomized clinical trial.

OBJECTIVES: This study examined the impact of premedication with ibuprofen and ibuprofen-arginine and the influence of preoperative pain and anxiety on inferior alveolar nerve block (IANB) efficacy in cases of symptomatic irreversible pulpitis. MATERIALS AND METHODS: The study involved 150 SIP patients who were randomly assigned to receive ibuprofen (600 mg), ibuprofen-arginine (1,155 mg), or a placebo 30 min before IANB. Preoperative anxiety and pain levels were assessed using the Modified Dental Anxiety Scale and the Heft-Parker visual scale. IANB efficacy was determined by the absence of or mild pain during the procedure. Statistical analysis included chi-square, z-tests, Analysis of Variance, and Student's t tests. RESULTS: The ibuprofen and ibuprofen-arginine groups exhibited significantly higher IANB success rates (62% and 78%, respectively) compared to the placebo group (34%). However, no significant difference was observed between the ibuprofen and ibuprofen-arginine groups. Patients with successful IANB in the ibuprofen and ibuprofen-arginine groups displayed lower median anxiety scores (8) than those with failed blocks (15) and lower mean preoperative pain scores (118.3). CONCLUSION: In cases of symptomatic irreversible pulpitis the preemptive medication with ibuprofen-arginine effectively increased the efficacy of the inferior alveolar nerve block The inferior alveolar nerve block efficacy was influenced by preoperative anxiety levels and the intensity of pain. CLINICAL RELEVANCE: This research underscores the potential benefits of oral premedication with ibuprofen and ibuprofen-arginine in improving anesthesia outcomes in cases of symptomatic irreversible pulpitis.

Frequency and Risk Factors of Maxillary Sinusitis of Endodontic Origin Evaluated by a Dynamic Navigation and a New Filter of Cone-Beam Computed Tomography.

INTRODUCTION: The aim of this study was to determine the frequency and risk factors of maxillary sinusitis of endodontic origin (MSEO) on posterior maxillary teeth evaluated using dynamic navigation and a novel filter of cone-beam computed tomographic (CBCT) imaging. METHODS: CBCT scans of 453 patients (814 teeth) were selected. Data were divided into 4 groups: (1) root canal treatment (RCT), (2) relation of the root apex to the maxillary sinus, (3) apical periodontitis (AP), and (4) maxillary sinus inflammation (no inflammation, periapical osteoperiostitis, periapical mucositis, partial obstruction, or total obstruction). Frequency distribution and cross-tabulation were used for data analysis. The association of maxillary sinus abnormalities with other variables was analyzed using the chi-square test. The significance level was set at 5%, and the association between dependent and independent variables was analyzed using robust Poisson regression models. RESULTS: MSEO was found in 65.6% of the cases, and the highest frequency rates were in the periapical mucositis (44%) and partial obstruction (15.8%) groups. The rates of risk factors were highest in the cases of RCT (54.9%), AP (34.3%), and the root apex in contact with the maxillary sinus (53.8%). The most frequent sex and age group were female (55.8%) and 41-50 years (30.5%). CONCLUSIONS: The frequency of MSEO was high and positively associated with RCT, AP, and the root apex's position in contact with the floor of the maxillary sinus. The maxillary sinus filter of the CBCT software provides a clear image of maxillary sinus abnormalities.

A Conservative Approach to Surgical Management of Root Canal Perforation.

This study describes a conservative approach to surgical management of root canal perforation in maxillary lateral incisors. A patient was referred for retreatment of a maxillary lateral incisor. Her chief complaint was discomfort in the buccal mucosa. Periapical radiography showed radiopaque material consistent with sealing material inside the root canal. A CBCT scan was acquired and revealed a gutta-percha cone outside the root canal, from the middle third to beyond the root apex. The imaging examination showed that the pulp cavity had not been affected. Thus, we took the clinical alternative of surgically managing the perforation by sealing with MTA, thereby avoiding endodontic treatment, and followed up with only clinical and radiographic control. At the two-year follow-up, after the surgical procedure to remove the extruded filling material, we observed bone tissue formation and positive response to pulp tests, without any clinical signs or symptoms. Root perforation is considered an unpleasant error in an operative procedure. Once a perforation is properly diagnosed, located, and sealed with biomaterial, a favorable prognosis is often achieved. MTA offered good sealing of the perforation, with promising results. Decision-making using the CBCT scan enabled us to adopt a conservative approach and favored more reliable treatment predictability.

Potential of a New Cone-Beam CT Software for Blooming Artifact Reduction.

This study evaluated the dimensions of intraradicular posts using a new cone beam CT (CBCT) software, and verified the potential of blooming artifact reduction. Sixty-three single-rooted human teeth were shaped, obturated, prepared for intracanal post placement and distributed into three groups: G1: anatomically customized prefabricated glass fiber posts; G2: low-fusion alloy posts; G3: gold alloy posts. After post fabrication and luting with RelyX U200®, specimens were sectioned axially at 9 mm from the root apex, and markings were made on the root surfaces (X-, Y- and Z-axes). The dimensions of the original posts (control group) were measured using a digital micrometer. CBCT scans of the teeth were obtained using a PreXion 3D Elite® scanner. Posts were measured on CBCT scans using DICOM files and the e-Vol DX software. A specific filter, Blooming Artefact Reduction (BAR), was developed to analyze intracanal posts. Statistical data were evaluated using the Van de Waerden nonparametric analysis of variance and, after that, normalized data were analyzed using the Tukey test. The level of significance was set at α = 5%. The measures of the anatomical prefabricated, low-fusion alloy and gold alloy intracanal posts obtained using the e-Vol DX CBCT software and a micrometer were not significantly different (p>0.05). The use of the BAR filter of the e-Vol DX software application did not induce any dimensional differences on CBCT scans of intracanal posts when compared with measurements made with a micrometer on original posts. The use of the BAR filter eliminated blooming artifacts.

Method to Determine the Root Canal Anatomic Dimension by using a New Cone-Beam Computed Tomography Software.

This study discusses a method to determine the root canal anatomic dimension by using e-Vol DX software. The methodology consists in initially establishes the correct positions which will be measured, define the point on the edge of the anatomical structure, and next adjust the intermediate position in the grayscale of CBCT image. Afterward, thin sections (0.10 mm) are obtained from 3D reconstructed slices in the filter for the measurements, in order to determine the edge of the anatomical surface in the axial plane. A replication of positions in 3D mode is done in multiplanar reconstruction (MPR) of CBCT images, where the correct position is established with the aid of a positioning guide. The 3D density is adjusted so that it is in the same dimension as the 2D image, and a dimension calibration occurs to the point where there is a coincidence between 3D and 2D. This calibration is done only at the beginning of the measurement. Next, the intermediate position of the division between the grayscale is verified in the CBCT scan. Once one side has been completed, it is moved to the other side and follows the same guidelines described above. When setting the position of the courses in the other margin, being that 2D mode is used as reference. Thus, one obtains the required measure, being checked in the two points. The creation of this filter in the e-Vol DX software for measurement, and its appropriate management, allows more effective applications when it is desired to obtain diameters of anatomical structures.

Demetallization of Enterococcus faecalis biofilm: a preliminary study.

Objectives To determine the concentration of calcium, iron, manganese and zinc ions after the application of chelator to Enterococcus faecalis biofilms. Material and Methods Fifty bovine maxillary central incisors were prepared and inoculated with E. faecalis for 60 days. The following were used as irrigation solutions: 17% EDTA (pH 3, 7 and 10), 2.5% sodium hypochlorite (NaOCl) combined with 17% EDTA (pH 3, 7 and 10), distilled water (pH 3, 7 and 10), and 2.5% NaOCl. Each solution was kept in the root canal for five minutes. Fifteen uncontaminated root canals were irrigated with 17% EDTA (pH 3, 7 and 10). Six teeth were used as bacterial control. The number of calcium, iron, manganese and zinc ions was determined using flame atomic absorption spectrometry. Mean ± standard deviation (SD) values were used for descriptive statistics. Results Calcium chelation using 17% EDTA at pH 7 was higher than at pH 3 and 10, regardless of whether bacterial biofilm was present. The highest concentration of iron occurred at pH 3 in the presence of bacterial biofilm. The highest concentration of manganese found was 2.5% NaOCl and 17% EDTA at pH 7 in the presence of bacterial biofilm. Zinc levels were not detectable. Conclusions The pH of chelating agents affected the removal of calcium, iron, and manganese ions. The concentration of iron ions in root canals with bacterial biofilm was higher after the use of 17% EDTA at pH 3 than after the use of the other solutions at all pH levels.

Common Operative Procedural Errors and Clinical Factors Associated with Root Canal Treatment.

Operative procedural errors must be well analyzed in order to avoid influence negatively the root canal treatment (RCT) prognosis. The successful RCT prevents tooth loss and avoids pain and apical periodontitis. This review aimed to categorize common operative procedure errors and clinical factors associated with RCT. Based on this, will be approached common errors of procedures within the clinical operative sequence: endodontic treatment planning, pulp and periapical disease diagnosis, anaesthesia, access cavity preparation, isolation with rubber dam, root canal preparation, root canal filling and retreatment, restoration of endodontically treated teeth, postoperative pain, follow up of endodontically treated teeth. The professional must remind that in each phase of RCT an operative error may have adverse implication on prognosis, and these errors characterize risk factors to failure. The knowledge of probable operative procedural errors and its consequences are essentials to avoid future problems to the tooth health.

Oxygen Saturation in the Dental Pulp of Maxillary Premolars in Different Age Groups - Part 1.

The aim of this study was to determine oxygen saturation levels in the dental pulp of maxillary premolars in different age groups. A total of 120 human maxillary premolars with normal dental pulps were selected covering the following age groups: 20-24, 25-29, 30-34, 35-39 and 40-44 years (n=24 each group). Oxygen saturation was assessed using pulse oximetry. Analysis of variance was used to assess differences in oxygen saturation levels and Tukey's test was used to identify the age groups that differed from each other. Significance was set at 0.05. Mean oxygen saturation of 120 premolars was 86.20% considering all age groups. Significantly reduced levels were found in the oldest group compared to the other groups: 40 to 44 years - 80.00% vs. 89.71, 87.67, 88.71, and 84.80% for age groups 20-24, 25-29, 30-34, 35-39 years, respectively. The mean oxygen saturation levels were similar between 20 and 39 years of age (86.20%) in the whole sample, but reduced significantly in the 40-44-year age group, suggesting that older patients present lower oxygen saturation results even in the absence of pulp tissue injury.

Antimicrobial potential of ozone in an ultrasonic cleaning system against Staphylococcus aureus.

The aim of this study was to evaluate the antimicrobial potential of ozone applied to 3 different solutions in an ultrasonic cleaning system against Staphylococcus aureus. A total of 120 mL of S. aureus were mixed in 6 L of the experimental solutions (sterile distilled water, vinegar and sterile distilled water + Endozime AWpluz) used in a ultrasonic cleaning system (UCS). Ozone was produced by an electric discharge through a current of oxygen and bubbling with flow rate at 7 g/h ozone (1.2%) into the microbial suspensions. Ten mL of each experimental suspension were collected and 5 fold dilutions were made in 9 mL of BHI and incubated at 37 degrees C for 48 h. Bacterial growth was evaluated by turbidity of the culture medium. At the same time, 1 mL of bacterial samples was collected and inoculated in BHIA plates. After incubation at 37 degrees C for 48 h, the number of colony forming units (cfu) per mL on BHIA surface was counted. In dilution test in BHI tubes and in BHIA plates (cfu/mL), bacterial growth was not observed in any of the experimental solutions when ozone was added. Under the tested conditions, it may be concluded that the addition of ozone to a ultrasonic cleaning system containing different experimental solutions resulted in antibacterial activity against S. aureus.

Evaluation of Periapical Lesions and Their Association with Maxillary Sinus Abnormalities on Cone-beam Computed Tomographic Images.

INTRODUCTION: Periapical inflammation is often responsible for distinct maxillary sinus (MS) changes. This retrospective, cross-sectional study evaluated the association between the clinical characteristics of periapical lesions (presence, size, and distance) in maxillary posterior teeth and the presence of sinus abnormalities by evaluating cone-beam computed tomographic (CBCT) images obtained from an archived collection. Apart from sex, no other patient information was available. METHODS: The study sample was composed of CBCT images of 143 MSs of patients with at least 1 maxillary posterior tooth with a periapical lesion and 178 MSs of patients without periapical radiolucent lesions. Sinus abnormalities were classified as mucosal thickening, sinus polyp, antral pseudocyst, nonspecific opacification, periostitis, and antral calcification; periapical radiolucent areas were classified using the CBCT periapical index, and the distance between the periapical lesion edge and the MS floor was measured. Data were analyzed using chi-square tests at a level of significance set at α = 0.05. RESULTS: Most sinus abnormalities were associated with at least 1 maxillary posterior tooth with a periapical lesion (P > .05). The most frequent sinus abnormality in the presence of a periapical lesion was mucosal thickening. All teeth with a CBCT periapical index score of 5 were associated with sinus abnormalities. The highest frequency of abnormalities was found when the radiolucent area was subjacent to the sinus floor. CONCLUSIONS: Maxillary posterior teeth with periapical radiolucent lesions had the highest frequency of sinus abnormalities. The size of a periapical lesion was not associated with the frequency of sinus abnormalities. A close spatial relationship between periapical lesions and sinuses resulted most frequently in sinus abnormalities.

Identification of Apical and Cervical Curvature Radius of Human Molars.

To determine the frequency of apical and cervical curvatures in human molars using the radius method and cone-beam computed tomography (CBCT) images. Four hundred images of mandibular and maxillary first and second molars were selected from a database of CBCT exams. The radius of curvature of curved root canals was measured using a circumcenter based on three mathematical points. Radii were classified according to the following scores: 0 - straight line; 1 - large radius (r > 8 mm, mild curvature); 2 - intermediate radius (r > 4 and r < 8 mm, moderate curvature); and 3 - small radius (r ≤ 4 mm, severe curvature). The frequency of curved root canals was analyzed according to root canal, root thirds, and coronal and sagittal planes, and assessed using the chi-square test (significance at α = 0.05). Of the 1,200 evaluated root canals, 92.75% presented curved root canals in the apical third and 73.25% in the cervical third on coronal plane images; sagittal plane analysis yielded 89.75% of curved canals in the apical third and 77% in the cervical third. Root canals with a large radius were significantly more frequent when compared with the other categories, regardless of root third or plane. Most root canals of maxillary and mandibular first and second molars showed some degree of curvature in the apical and cervical thirds, regardless of the analyzed plane (coronal or sagittal).

Frequency of Root Canal Isthmi in Human Permanent Teeth Determined by Cone-beam Computed Tomography.

INTRODUCTION: This study evaluated the frequency of root canal isthmi (RCIs) in human permanent teeth by using cone-beam computed tomography. METHODS: A sample of 1400 teeth of 618 patients (394 women; mean age, 43.4 years) was selected. RCIs were detected longitudinally on 0.1-mm/0.1-mm axial slices of cone-beam computed tomography images of roots scanned from the pulp orifice to the apex, and findings were classified into 7 categories according to RCIs beginning and end: (1) both in the cervical third, (2) begin in the cervical third and end in the middle third, (3) begin in the cervical third and end in the apical third, (4) both in the middle third, (5) begin in the middle third and end in the apical third, (6) both in the apical third, or (7) no isthmus. A χ(2) test with Yates correction or the Fisher exact test was used to analyze categorical variables, described as frequencies (%). The Student t test was used to compare quantitative variables. RESULTS: RCI is a common anatomic structure in human permanent teeth, except in maxillary anterior teeth. CONCLUSIONS: The higher frequencies of RCIs (87.9%) were found in mandibular first molars. The frequencies of RCIs according to mean age and tooth group were not significantly different (P > .05), except in mandibular central incisors. RCIs were less frequent among older patients.

Antimicrobial effect of 2% sodium hypochlorite and 2% chlorhexidine tested by different methods.

The objective of this study was to analyze the antimicrobial effect of 2% sodium hypochlorite (NaOCl) and 2% chlorhexidine (CHX) by agar diffusion test and by direct exposure test. Five microorganisms: Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aernginosa, Bacillus subtilis, Candida albicans, and one mixture of these were used. These strains were inoculated in brain heart infusion (BHI) and incubated at 37 degrees C for 24 h. For the agar diffusion test (ADT), 18 Petri plates with 20 ml of BHI agar were inoculated with 0.1 ml of the microbial suspensions, using sterile swabs that were spread on the medium, obtaining growth injunction. Fifty-four paper disks (9 mm in diameter) were immersed in the experimental solutions for 1 min. Subsequently, three papers disks containing one of the substances were placed on the BHI agar surface in each agar plate. The plates were maintained for 1 h at room temperature, and then incubated at 37 degrees C for 48 h. The diameter of microbial inhibition was measured around the papers disks containing the substances. For the direct exposure test, 162#50 sterile absorbent paper points were immersed in the experimental suspensions for 5 min, and were then placed on Petri plates and covered with one of the irrigant solutions, or with sterile distilled water (control group). After intervals of 5, 1 0 and 30 min, the paper points were removed from contact with the solutions and individually immersed in 7 ml of Letheen Broth, followed by incubation at 37 degrees C for 48 h. Microbial growth was evaluated by turbidity of the culture medium. A 0.1 ml inoculum obtained from the Letheen Broth was transferred to 7 ml of BHI, and incubated at 37 degrees C for 48 h. Bacterial growth was again evaluated by turbidity of the culture medium. Gram stain of BHI cultures was used for verification of contamination and growth was determined by macroscopic and microscopic examination. The best performance of antimicrobial effectiveness of NaOCI was observed in the direct exposure test, and of CHX was observed in the agar diffusion test. The magnitude of antimicrobial effect was influenced by the experimental methods, biological indicators and exposure time.

Root canal filling with calcium hydroxide using different techniques.

Several different techniques for placing calcium hydroxide into root canals have been proposed, such as amalgam carriers, vertical pluggers, McSpadden compactors, Lentulo drills, files and special syringes. Because correct filling of the root canal is necessary for calcium hydroxide paste to act effectively, the aim of this research was to study different techniques of root canal filling with calcium hydroxide pastes in dog teeth. The placement of calcium hydroxide with a file, absorbent paper points and vertical pluggers presented the lowest number of empty spaces in the three thirds of the root canal, followed by the Lentulo drill and the McSpadden compactor.

Mechanism of action of sodium hypochlorite.

The choice of an irrigating solution for use in infected root canals requires previous knowledge of the microorganisms responsible for the infectious process as well as the properties of different irrigating solutions. Complex internal anatomy, host defenses and microorganism virulence are important factors in the treatment of teeth with asymptomatic apical periodontitis. Irrigating solutions must have expressive antimicrobial action and tissue dissolution capacity. Sodium hypochlorite is the most used irrigating solution in endodontics, because its mechanism of action causes biosynthetic alterations in cellular metabolism and phospholipid destruction, formation of chloramines that interfere in cellular metabolism, oxidative action with irreversible enzymatic inactivation in bacteria, and lipid and fatty acid degradation. The aim of this work is to discuss the mechanism of action of sodium hypochlorite based on its antimicrobial and physico-chemical properties.

Method to determine the root canal anatomic dimension by using a new cone-beam computed tomography software

Abstract This study discusses a method to determine the root canal anatomic dimension by using e-Vol DX software. The methodology consists in initially establishes the correct positions which will be measured, define the point on the edge of the anatomical structure, and next adjust the intermediate position in the grayscale of CBCT image. Afterward, thin sections (0.10 mm) are obtained from 3D reconstructed slices in the filter for the measurements, in order to determine the edge of the anatomical surface in the axial plane. A replication of positions in 3D mode is done in multiplanar reconstruction (MPR) of CBCT images, where the correct position is established with the aid of a positioning guide. The 3D density is adjusted so that it is in the same dimension as the 2D image, and a dimension calibration occurs to the point where there is a coincidence between 3D and 2D. This calibration is done only at the beginning of the measurement. Next, the intermediate position of the division between the grayscale is verified in the CBCT scan. Once one side has been completed, it is moved to the other side and follows the same guidelines described above. When setting the position of the courses in the other margin, being that 2D mode is used as reference. Thus, one obtains the required measure, being checked in the two points. The creation of this filter in the e-Vol DX software for measurement, and its appropriate management, allows more effective applications when it is desired to obtain diameters of anatomical structures.

Resumo Este estudo discute um método para determinar a dimensão anatômica do canal radicular usando o software e-Vol DX. A metodologia consiste em inicialmente estabelecer as posições corretas que serão medidas, definir o ponto na borda da estrutura anatômica e ajustar a posição intermediária na escala de cinza na imagem em tomografia computadorizada de feixe cônico (TCFC). A seguir, slices finos (0,10mm) são obtidos a partir de cortes 3D reconstruídos no filtro para as medidas, a fim de determinar a borda da superfície anatômica no plano axial. Uma replicação de posições no modo 3D é feita em reconstrução multiplanar (MPR) em imagens de TCFC, onde a posição correta é estabelecida com o auxílio de um guia de posicionamento. A densidade 3D é ajustada de modo a ficar na mesma dimensão da imagem 2D, e então realiza-se uma calibração de dimensão até o ponto em que há uma coincidência entre o modo 3D e 2D. Essa calibração é feita apenas no início da medição. Posteriormente, a posição intermediária da divisão entre a escala de cinza é verificada na TCFC. Uma vez que um lado tenha sido concluído, o guia é movido para o outro lado, e segue-se as mesmas diretrizes descritas. Define-se a posição do marcador na outra margem, sendo que o modo 2D usado como referência. Assim, obtém-se a medida necessária, sendo verificado nas duas margens do canal radicular. A criação deste filtro no software e-Vol DX para medição e seu uso apropriado permite aplicações eficazes quando se deseja obter diâmetros de estruturas anatômicas.

Ortodontia interceptativa no tratamento de mordida cruzada posterior bilateral e mordida aberta anterior: relato de caso / Interceptive orthodontics in the treatment of bilateral posterior crossbite and anterior open bite: case report

O diagnóstico e a intervenção precoce da má oclusão, possibilitam um crescimento adequado do complexo maxilo mandibular. O objetivo deste trabalho é apresentar um relato de caso clínico de um paciente em fase de dentadura mista que apresentava mordida aberta anterior e mordida cruzada posterior bilateral. Foi proposto a instalação de um disjuntor maxilar tipo Haas. Considerações finais: Após a instalação do aparelho o paciente interrompeu o hábito de sucção digital que possuía. A expansão maxilar promovida pelo expansor Haas associada à interrupção do hábito, resultaram na correção da mordida aberta e mordida cruzada posterior bilateral. Paciente faz uso de placa de Hawley para contenção há 9 meses.

Diagnosis and early intervention of malocclusion enable adequate growth of the mandibular maxillary complex. The aim of this paper is to report a case of a patient with mixed dentition who presented anterior open bite and bilateral posterior crossbite. It has been proposed to install a Haas type jaw breaker. Final considerations: After the device was installed, the patient discontinued his digital sucking habit. The maxillary expansion promoted by Haas expander associated with the interruption of the habit resulted in the correction of the open bite and bilateral posterior crossbite. Patient has been using Hawley plaque for retention for 9 months.

Effect of gutta-percha solvents on fiberglass post bond strength to root canal dentin.

The purpose of this study was to investigate the influence of gutta-percha solvents on the bond strength of fiberglass post to root canal dentin. Forty bovine incisors were decoronated, prepared, filled, and randomly distributed into four groups (n = 10) according to the gutta-percha solvent used: control, xylene, eucalyptol and orange oil. After root canal treatment, the posts were cemented into the prepared root canals using a resin-based cement. A micro push-out test was executed, and the patterns of failure were assessed with microscopy. The data were analyzed using two-way ANOVA followed by Tukey's test. The control group exhibited greater bond strength compared to the eucalyptol group in the cervical and middle thirds of the root (P < 0.05); however, it did not differ significantly from the xylene and orange oil groups (P > 0.05). No difference was observed in the values of the xylene, orange oil, and eucalyptol groups (P > 0.05). The cervical third had higher values than the apical third for all tested solvents (P < 0.05). Adhesive failure between resin cement and dentin was the most frequent type of failure. The use of xylene and orange oil as gutta-percha solvents did not influence the bond strength of fiberglass posts to root canal dentin.

Detection of apical inflammatory root resorption associated with periapical lesion using different methods.

The aim of this study was to detect apical inflammatory root resorption (AIRR) associated with periapical lesion using cone beam computed tomography (CBCT) and scanning electronic microscopy (SEM). This clinical study evaluated AIRR in 88 root apexes, from 52 permanent teeth of 14 patients, extracted for different reasons. The patients were submitted to a clinical interview, review of dental/medical histories and clinical/imaging examinations for treatment planning. All selected teeth showed unrestorable condition because of the extensive coronal breakdown due to carious lesions, and root canal infection associated with periapical lesions. CBCT images were obtained from the patients with the aim of diagnosing the periapical diseases which showed complex or doubtful conditions. Two examiners assessed the presence or absence of AIRR. Apices were also analyzed under SEM. Chi-square test was used to compare the imaging methods for detection of AIRR. The level of statistical significance was set at 5%. AIRR associated with root canal infection and apical periodontitis was found in 61.4% of the cases studied by using SEM, and at least half of the cases by CBCT. The microscopic analysis remains as a reference standard against the imaging method to identify AIRR.

Demetallization of Enterococcus faecalis biofilm: a preliminary study

Abstract Objectives To determine the concentration of calcium, iron, manganese and zinc ions after the application of chelator to Enterococcus faecalis biofilms. Material and Methods Fifty bovine maxillary central incisors were prepared and inoculated with E. faecalis for 60 days. The following were used as irrigation solutions: 17% EDTA (pH 3, 7 and 10), 2.5% sodium hypochlorite (NaOCl) combined with 17% EDTA (pH 3, 7 and 10), distilled water (pH 3, 7 and 10), and 2.5% NaOCl. Each solution was kept in the root canal for five minutes. Fifteen uncontaminated root canals were irrigated with 17% EDTA (pH 3, 7 and 10). Six teeth were used as bacterial control. The number of calcium, iron, manganese and zinc ions was determined using flame atomic absorption spectrometry. Mean ± standard deviation (SD) values were used for descriptive statistics. Results Calcium chelation using 17% EDTA at pH 7 was higher than at pH 3 and 10, regardless of whether bacterial biofilm was present. The highest concentration of iron occurred at pH 3 in the presence of bacterial biofilm. The highest concentration of manganese found was 2.5% NaOCl and 17% EDTA at pH 7 in the presence of bacterial biofilm. Zinc levels were not detectable. Conclusions The pH of chelating agents affected the removal of calcium, iron, and manganese ions. The concentration of iron ions in root canals with bacterial biofilm was higher after the use of 17% EDTA at pH 3 than after the use of the other solutions at all pH levels.