FM - Faculdade de Medicina
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A FM - Faculdade de Medicina, da Universidade Federal de Goiás, oferece curso de Graduação em: Medicina. Além de Especialização em: Saúde.
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Item Análise microscópica de polpas de dentes humanos permanentes traumatizados(2009) Bruno, Kely Firmino; Alencar, Ana Helena Gonçalves de; Estrela, Carlos; Batista, Aline Carvalho; Pimenta, Fabiana CristinaThis study microscopically analyzed the pulp of 20 human permanent traumatized teeth with intact crowns and clinical diagnosis of pulp necrosis, and evaluated this diagnosis concerning histopatologic findings. The removed pulp specimens were stained with hematoxylin and eosin, for evaluation of possible morphological alterations, and Brown e Brenn method, to verify microorganisms. General subjective analysis and statistical analyses (diagnostic analysis) revealed that 3 teeth (15%) did not present pulp tissue, being characterized as complete autolysis; analysis of pulp samples was performed on the other 17 (85%) cases, among which 3 (15%) exhibited partial necrosis without possibility of repair and 14 (70%) presented complete necrosis; in 12 (65%) out of 17 pulps the presence of microorganisms could be conformed by Brown and Brenn method and none of the clinical criteria employed for the diagnosis of pulp necrosis in traumatized teeth was pathognomonic. The present results allowed the following conclusions: concerning the microscopic findings, 100% of traumatized teeth presented pulp necrosis and 65% of them with microorganisms; the pulp vitality tests to heat, cold and vertical percussion test were the most reliable to diagnose pulp necrosis in traumatized teeth.Item Analysis of 261 avulsed permanent teeth of patients treated in a dental urgency service(2015-03) Guedes, Orlando Aguirre; Borges, Álvaro Henrique; Bandeca, Matheus Coelho; Estrela, Cyntia Rodrigues de Araújo; Alencar, Ana Helena Gonçalves de; Estrela, CarlosObjective: The aim of this study was to evaluate the epidemiological aspects and clinical factors associated with avulsion of permanent teeth. Materials and Methods: The sample consisted of 261 avulsed teeth of 170 patients seen in the Dental School of the Federal University of Goiás, Brazil, from 2000 to 2008. Result: The highest incidence was found among boys (71.18%) aged 6-15 years (61.18%). The main etiologic factors were falls (51.76%) and traffic accidents (29.41%). Most cases occurred in autumn (March to June; 31.18%) and winter (June to September; 27.65%). Most avulsed teeth were the maxillary central incisor (62.45%), followed by the maxillary lateral incisor (21.46%). A high proportion (67.23%) of injured teeth had a completely formed root apex. Replantation was used to treat 119 teeth (45.59%) in 86 patients. Most replantations were delayed (89.08%). Thirty-eight teeth (31.93%) were stored in dry media. Periodontal healing was found in 41 teeth (34.45%), inflammatory root resorption, in 44 (36.97%) and replacement root resorption, in 22 (18.49%). The most frequent treatments for replanted teeth were endodontic treatment and temporary filling of the root canal with calcium hydroxide (58.92%) and endodontic treatment and definitive root canal filling (26.89%). Conclusion: The epidemiological and clinical aspects of tooth avulsion in this study were similar to those reported in other studies. The number of replantation was low, the number of teeth stored in non-physiological conditions was high, and replantation was often delayed.Item Apical root resorption due to orthodontic treatment detected by cone beam computed tomography(2013) Castro, Iury Oliveira; Alencar, Ana Helena Gonçalves de; Valladares Neto, José; Estrela, CarlosObjective: To determine the frequency of apical root resorption (ARR) due to orthodontic treatment using cone beam computed tomography (CBCT) in a sample of 1256 roots from 30 patients. Materials and Methods: All patients had Class I malocclusion with crowding. Of the 30 patients evaluated, 11 were boys and 19 were girls; their mean age was 13 years (11 to 16 years). Orthodontic treatment followed the nonextraction treatment. CBCT images were obtained before and after orthodontic treatment, and ARR was determined using Axial Guided Navigation of CBCT images. Results: All patients had ARR. No statistically significant association was found between resorption frequency, gender, and age. ARR was detected using CBCT in 46% of all roots that underwent orthodontic treatment. Conclusions: CBCT was effective for detecting in vivo even minimal degrees of ARR due to orthodontic treatment and allowed three-dimensional evaluation of dental roots and visualization of palatine roots of maxillary molars. The highest frequencies and the most significant ARR occurred in incisors and distal roots of first maxillary and mandibular molars. (Angle Orthod. 2013;83:196– 203.)Item Apical root resorption of maxillary fi rst molars related to headgear use as detected by cone beam computed tomography(2011-12) Freitas, Jairo Curado de; Lyra, Olavo César Porto; Alencar, Ana Helena Gonçalves de; Estrela, CarlosExtraoral traction (EOT) by occipital headgear is a widely used anchorage and orthopedic approach for the control of maxillary growth. The aims of this study were: 1) to test the hypothesis that headgear use may increase the risk of apical root resorption, using cone beam computed tomography (CBCT) to detect root resorptions of maxillary fi rst molars, and 2) to assess which roots are more prone to resorption and to which extent. A total of 112 maxillary fi rst molars from 56 patients at 52 to 288 months after orthodontic treatment were evaluated to detect apical root resorption on CBCT images. Patients were divided into two groups: Group 1, patients who used EOT for up to six months; Group 2, patients who did not use EOT. The Levander and Malmgren scoring system was used to classify the root apices of maxillary fi rst molars. Signifi cance was set at 5%. Kappa statistics was used to assess agreement; scores were evaluated twice, according to the study methods. There were no differences in the frequency and severity of apical root resorption of maxillary fi rst permanent molars in the two groups as detected by CBCT. The use of EOT did not show association with frequency and severity of ARR considering a long time of follow up.Item Avaliação da dor e de testes de vitalidade para o diagnóstico da inflamação pulpar(1995) Estrela, Carlos; Lopes, Hélio Pereira; Resende, Edison Vivas de; Alencar, Ana Helena Gonçalves deItem Avaliação da padronização e da precisão de réguas endodônticas milimetradas utilizadas para odontometria em endodontia(2005) Alencar, Ana Helena Gonçalves de; Bruno, Kelly Firmino; Arruda, Moema Fernandes de; Barnabé, WilliamThe endodontic millimetered ruler is necessary to transfer working length to the endodontic instrument. It must be standardized and accurate to avoid mistakes in interpretation or measurement which may compromise the success of endodontic therapy. The purpose of this study was thus to evaluate the standardization and accuracy of four different brands of millimetered rulers used for endodontic odontometry. Eighty rulers were selected and included in four groups of twenty each, according to brand: 1. Malleifer; 2. Jon; 3. no brand name; and 4. Imagem. They were measured with a profile projector. Three cycles were carried out for each position with reference points from 15 to 25 mm at a temperature of 19.9 °C. as measured by a thermohygrometer. After statistical analysis using Friedman and linear regression tests, it was concluded that there was no standardization among the four brands of endodontic rulers tested. All of the endodontic rulers, whatever the brand, were imprecise in their measurements. Of the four groups, the no-brand rulers were the most accurate, followed by Imagem, Jon and Malleifer.Item Avaliação qualitativa do preparo de canais radiculares realizado “in vitro” com instrumentos rotatórios de níquel - titânio RaCe e K3(2010) Carvalho, Lúcia M.; Silva, Julio Almeida; Decurcio, Daniel de Almeida; Crosara, Mariana Borges; Alencar, Ana Helena Gonçalves deThe aim of this study was to analyze the taper and regulari- ty of root canals prepared with rotary nickel-titanium system Race ® and K3 ® , using angle reducer Dentflex ® . The experiment involved mesial canals of thirty human molars, upper and lo- wer were randomly assigned to two groups of fifteen, according to the two types of rotary instruments: RaCe ® and K3 ® . Since then, there was casting of root canals, to then subject the teeth to demineralization in 35% hydrochloric acid, thereby obtaining the same mold. These patterns were analyzed, where there was a taper and regularity of root canals prepared. The data were tabulated and analyzed statistically by the Mann-Whitney and Chi-square. The results indicate the predominance of regular conical forms, in all thirds (cervical, middle, apical) in mesial buccal and mesial lingual and palatine canals prepared with Race ® and K3 ® , but statistically significant difference between the number of occurrence of irregular cylindrical shape along the lines of mesiobuccal canals below, prepared with RaCe ® .Item Avaliação radiográfica da posição e forma do forame mentual em uma subpopulação Brasileira(2011) Guedes, Orlando Aguirre; Rabelo, Luiz Eduardo Gregoris; Porto, Olavo Cesar Lyra; Alencar, Ana Helena Gonçalves de; Estrela, CarlosObjective: It was evaluated the position and shape of mental foramen on digital panoramic radiographs in a Brazilian sub- population. Material and Methods: Five hundred and eighteen panoramic radiographs were consecutively selected from a sec- ondary database from a private radiology clinic and analyzed according to age, gender and symmetry. Two specialists in den- tal radiology determined the horizontal and vertical positions and the format of 1036 mental foramen. Results: The highest frequency of the mental foramen was located between the long axis of the first and second premolars (55.89%). There was no difference in horizontal position in relation to gender and age Symmetries were observed in 68.91% of the sample. The vertical positioning of the foramen showed a common location below the apex of the first and second lower premolars (55.31%). Dif- ference in vertical relationship was observed only in patients aged 10 to 20 years. Symmetries were observed in 84.36% of cases. A large number of mental foramen had undefined/irregu- lar contours (62.74%), with symmetries in 68.15%. Conclusion: The mental foramen is commonly presented below and between the first and second premolars and with undefined/irregular format.Item Avaliação radiográfica da posição e forma do forame mentual em uma subpopulação brasileira(2011) Guedes, Orlando Aguirre; Rabelo, Luiz Eduardo Gregoris; Porto, Olavo Cesar Lyra; Alencar, Ana Helena Gonçalves de; Estrela, CarlosObjective: It was evaluated the position and shape of mental foramen on digital panoramic radiographs in a Brazilian sub- population. Material and Methods: Five hundred and eighteen panoramic radiographs were consecutively selected from a sec- ondary database from a private radiology clinic and analyzed according to age, gender and symmetry. Two specialists in den- tal radiology determined the horizontal and vertical positions and the format of 1036 mental foramen. Results: The highest frequency of the mental foramen was located between the long axis of the first and second premolars (55.89%). There was no difference in horizontal position in relation to gender and age. Symmetries were observed in 68.91% of the sample. The vertical positioning of the foramen showed a common location below the apex of the first and second lower premolars (55.31%). Dif- ference in vertical relationship was observed only in patients aged 10 to 20 years. Symmetries were observed in 84.36% of cases. A large number of mental foramen had undefined/irregu- lar contours (62.74%), with symmetries in 68.15%. Conclusion: The mental foramen is commonly presented below and between the first and second premolars and with undefined/irregular format.Item Caracterização da imagem do canal radicular preenchido com hidróxido de cálcio na tomografia computadorizada de feixe cônico(2011) Estrela, Carlos; Decurcio, Daniel de Almeida; Silva, Julio Almeida; Porto, Olavo Cesar Lyra; Alencar, Ana Helena Gonçalves deAim: To characterize the image of the root canal filled in with calcium hydroxide in cone beam computed tomography (CBCT). Methodology: Twenty-seven root canals were prepared up to K-file #50, 1 mm below the foramen. After, the teeth were randomly divided into three groups: group 1- root canals filled in with calcium hydroxide paste associated with saline (n=9); group 2- root canals filled with Endo-Fill ® and gutta-percha (n=9); group 3- root canals without filling (n=9). After root canals preparation and filling, CBCT images were acquired and the specimens sectioned in axial, sagittal or coronal plans using Endo Z drills at high speed. Root canals measurements from cross sections of specimens were obtained using a digital caliper, and from CBCT images using the manufacturer’s software. The differences between the sizes of specimens and CBCT images were determined at different plans. Results: Specimens images of the group containing calcium hydroxide paste had densities similar to those ones observed in dentin, which did not allow the measurement in order to determine size change. The group filled in with Endo-Fill ® and gutta-percha showed an increase of 37.40% to 47.40% in the dimensions of radiopaque images. Conclusion: Images of cone beam computed tomography in root canals filled in with calcium hydroxide pastes showed densities similar to those of dentin, which did not determine dimensional changes. Care should be taken that these images are not confused with calcified canalsItem Caracterização da imagem do canal radicular preenchido com hidróxido de cálcio na tomografia computadorizada de feixe cônico(2011) Estrela, Carlos; Decurcio, Daniel de Almeida; Silva, Julio Almeida; Porto, Olavo Cesar Lyra; Alencar, Ana Helena Gonçalves de; Estrela, Cyntia Rodrigues de AraújoAim: To characterize the image of the root canal fil- led in with calcium hydroxide in cone beam computed tomography (CBCT). Methodology: Twenty-seven root canals were prepared up to K-file #50, 1 mm below the foramen. After, the teeth were ran- domly divided into three groups: group 1- root canals filled in with calcium hydroxide paste associated with saline (n=9); group 2- root canals filled with Endo-Fill ® and gutta-percha (n=9); group 3- root canals without filling (n=9). After root canals preparation and filling, CBCT images were acquired and the specimens sectioned in axial, sagittal or coronal plans using Endo Z drills at high speed. Root canals measurements from cross sections of specimens were obtained using a digital caliper, and from CBCT images using the manufacturer’s software. The differences between the sizes of specimens and CBCT images were determined at different plans. Results: Specimens images of the group containing cal- cium hydroxide paste had densities similar to those ones obser- ved in dentin, which did not allow the measurement in order to determine size change. The group filled in with Endo-Fill ® and gutta-percha showed an increase of 37.40% to 47.40% in the dimensions of radiopaque images. Conclusion: Images of cone beam computed tomography in root canals filled in with calcium hydroxide pastes showed den- sities similar to those of dentin, which did not determine dimen- sional changes. Care should be taken that these images are not confused with calcified canals.Item Characterization of calcium oxide in root perforation sealer materials(2012) Estrela, Carlos; Sousa Neto, Manoel Damião; Guedes, Orlando Aguirre; Alencar, Ana Helena Gonçalves de; Duarte, Marco Antonio Hungaro; Pécora, Jesus DjalmaRoot perforation represents an undesirable complication that may lead to an unfavorable prognosis. The aims of this study were to characterize and to compare the presence of calcium oxide (CaO) on the chemical composition of materials used for root perforation therapy: gray and white mineral trioxide aggregate (MTA) and Portland cement (PC), gray MTA+5%CaO and gray MTA+10%CaO. The last two materials were analyzed to evaluate the increase of CaO in the final sample. CaO alone was used as a standard. Eighteen polyethylene tubes with an internal diameter of 3 mm and 3 mm in length were prepared, filled and then transferred to a chamber with 95% relative humidity and a temperature of 37 o C. The chemical compounds (particularly CaO) and the main components were analyzed by energy-dispersive X-ray microanalysis (EDX). EDX revealed the following concentrations of CaO: gray MTA: 59.28%, white MTA: 63.09%; PC: 72.51%; gray MTA+5%CaO: 63.48% and gray MTA+10%CaO: 67.55%. The tested materials presented different concentrations of CaO. Even with an increase of 5 and 10% CaO in gray MTA, the CaO levels found in the MTA samples were lower than those found in PC.Item Characterization of successful root canal treatment(2014) Estrela, Carlos; Holland, Roberto; Estrela, Cyntia Rodrigues de Araújo; Alencar, Ana Helena Gonçalves de; Sousa Neto, Manoel Damiao de; Pécora, Jesus DjalmaKnowing the outcome of root canal treatment (RCT) is determinant to substantiate the clinical decision making process, especially when RCT is weighed against the extraction of natural teeth or replacement by prosthetic elements. The ideal scenario in all clinical situations should combine healing/prevention of disease (apical periodontitis) and the functional retention of the tooth. Understanding the risk factors associated with endodontic failure is a key factor to increase the chances of success. The logical action is to reverse the existing disease, which requires intervention to neutralize the bacterial invasion and disrupt the bacterial biofilm within the complex anatomy. Success is more predictable when the immune host defenses are favorable. However, success has different meanings to the dentist, to the patient and to the tooth itself. The life of an endodontically treated tooth depends on the accuracy of the diagnosis and planning, excellence of disinfection, instrumentation and filling procedures (antimicrobial strategies, root canal shaping and coronal and apical seal) and finally the rehabilitation management. The interpretation of constant or intermittent pain and/or discomfort associated with apical periodontitis (AP) in endodontically treated tooth may be suggestive of endodontic failure. The success features of RCT, namely absence of pain, regression of AP, tight seal of canal and coronal spaces, and recovery of tooth function, must be reevaluated over time. In case of doubt between success and failure, cone beam computed tomography (CBCT) could be indicated for detection and precise localization of AP. The possibility of map reading on CBCT images characterizes the real multidimensional structure, providing accurate information on the presence, absence or regression of AP. The survival of an endodontically treated tooth implies understanding the biological and mechanical outcomes as multifactorial events over the individual’s life span. The objective of this review of literature is to discuss relevant factors associated with patient’s health, tooth and dentist that could account for a successful RCT.Item Chemical elements characterization of root canal sealers using scanning electron microscopy and energy dispersive x-ray analysis(2014-03) Sampaio, Felipe Cavalcanti; Alencar, Ana Helena Gonçalves de; Guedes, Orlando Aguirre; Veloso, Heloisa Helena Pinho; Santos, Tatiane Oliveira dos; Estrela, CarlosIntroduction: The aim of this study was to evaluate the chemical elements composition of root canal filling materials using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray analysis (EDX). Methods: Eighteen standard polyethylene tubes were filled with the following materials: Sealapex®, Sealer 26®, MTA Fillapex®, Pulp Canal Sealer®, Endofill® and AH Plus®. After 48 hours at 37°C and 95% relative humidity, the samples were surface-sputtered with gold and analyzed using SEM at 5000X magnification. Their chemical composition and element distributionwere determined using EDX. Results were evaluated qualitatively (SEM images and elemental mapping) and quantitatively (weight percentage). Results: Calcium oxide- and hydroxide-based sealers (Sealapex® and Sealer 26®) had calcium peaks of 53.58 wt% and 65.00 wt%. MTA Fillapex® had 30.58 wt% of calcium and high amounts of silicon (31.02 wt%) and bismuth (27.38 wt%). Zinc oxide- and eugenol-based sealers, Pulp Canal Sealer® and Endofill®, had 67.74 wt% and 63.16 wt% of zinc each. AH Plus® had a higher amount of zirconium (64.24 wt%). All materials had elements other than those described by the manufacturers. Surface analysis using EDX revealed that regularity varied, element distribution was uniform, and particles had similar sizes and variable shapes. Conclusions: Most chemical elements were those described by the manufacturers, but percentages were different. The surface of root canal sealers had different regularity findings, uniform distribution and particles of similar sizes but variable shapes.Item Chemical elements characterization of root canal sealers using scanning electron microscopy and energy dispersive x-ray analysis(2014-03) Sampaio, Felipe Cavalcanti; Alencar, Ana Helena Gonçalves de; Guedes, Orlando Aguirre; Veloso, Heloisa Helena Pinho; Santos, Tatiane Oliveira dos; Estrela, CarlosIntroduction: The aim of this study was to evaluate the chemical elements composition of root canal filling materials using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray analysis (EDX). Methods: Eighteen standard polyethylene tubes were filled with the following materials: Sealapex ® , Sealer 26 ® , MTA Fillapex ® , Pulp Canal Sealer ® , Endofill ® and AH Plus ® . After 48 hours at 37°C and 95% relative humidity, the samples were surface-sputtered with gold and analyzed using SEM at 5000X magnification. Their chemical composition and element distributionwere determined using EDX. Results were evaluated qualitatively (SEM images and elemental mapping) and quantitatively (weight percentage). Results: Calcium oxide- and hydroxide-based sealers (Sealapex ® and Sealer 26 ® ) had calcium peaks of 53.58 wt% and 65.00 wt%. MTA Fillapex ® had 30.58 wt% of calcium and high amounts of silicon (31.02 wt%) and bismuth (27.38 wt%). Zinc oxide- and eugenol-based sealers, Pulp Canal Sealer ® and Endofill ® , had 67.74 wt% and 63.16 wt% of zinc each. AH Plus ® had a higher amount of zirconium (64.24 wt%). All materials had elements other than those described by the manufacturers. Surface analysis using EDX revealed that regularity varied, element distribution was uniform, and particles had similar sizes and variable shapes. Conclusions: Most chemical elements were those described by the manufacturers, but percentages were different. The surface of root canal sealers had different regularity findings, uniform distribution and particles of similar sizes but variable shapes.Item Cone-beam computed tomography as a diagnostic method for determination of gingival thickness and distance between gingival margin and bone crest(2015) Borges, Germana Jayme; Ruiz, Luís Fernando Naldi; Alencar, Ana Helena Gonçalves de; Porto, Olavo Cesar Lyra; Estrela, CarlosThe objective of the present study was to assess cone-beam computed tomography (CBCT) as a diagnostic method for determination of gingival thickness (GT) and distance between gingival margin and vestibular (GMBC-V) and interproximal bone crests (GMBC- I). GT and GMBC-V were measured in 348 teeth and GMBC-I was measured in 377 tooth regions of 29 patients with gummy smile. GT was assessed using transgingival probing (TP), ultrasound (US), and CBCT, whereas GMBC-V and GMBC-I were assessed by transsurgical clinical evaluation (TCE) and CBCT. Statistical analyses used independent t-test, Pearson’s correlation coefficient, and simple linear regression. Difference was observed for GT: between TP, CBCT, and US considering all teeth; between TP and CBCT and between TP and US in incisors and canines; between TP and US in premolars and first molars. TP presented the highest means for GT. Positive correlation and linear regression were observed between TP and CBCT, TP and US, and CBCT and US. Difference was observed for GMBC-V and GMBC-I using TCE and CBCT, considering all teeth. Correlation and linear regression results were significant for GMBC-V and GMBC-I in incisors, canines, and premolars. CBCT is an effective diagnostic method to visualize and measure GT, GMBC-V, and GMBC-I.Item A critical analysis of the sanitization strategies on root canal cleaning(2013-12) Silva, Julio Almeida; Caetano, Cairo Henrique Moura de Siqueira; Alencar, Ana Helena Gonçalves de; Estrela, Cyntia Rodrigues de Araújo; Borges, Alvaro Henrique; Decurcio, Daniel de Almeida; Estrela, CarlosObjective: To assess the effi cacy of irrigant solutions used in endodontic treatment in terms of cleanliness, smear layer removal and tissue dissolving potency by means of a systematic review of longitudinal studies. Method: Articles were identifi ed in electronic bibliographies accessible via MEDLINE. Searches were run on the PubMed Database (http://www.ncbi.nlm. nih.gov/PubMed) for articles published from 1966 to January 10, 2012, using combinations of the following keywords: (Endodontic or root canal) and (Smear layer or clean* or tissue dissolution or organic dissolution) and (irrigants or NaOCl or sodium hypochlorite or Milton Solution or Dakin solution or Labarraque solution or chlorinated soda or chlorine or chloride or hypoclean or hypochlor or niclor or Chlor-xtra or chlorhexidine or chx or cloreximid or peridex or periogard or EDTA or Acid or citric or acetic or peracetic or malic or vinegar or citrate or Hydrogen peroxide or H 2 O 2 or Iodine or iodide or povidone or povidine or PVP or Ozone or ozonated or MTAD or Tetraclean or Endoptc or Rc prep or Morinda citrifolia or Aquatine or hydroxyethylcellulose or cat’s claw or propolis). Studies were assessed for inclusion and exclusion criteria by two independent examiners. Results: The search returned 817 articles. Four (04) studies met the preestablished inclusion criteria and not the exclusion criteria. Teeth were assessed histologically at points 1, 2 and 3 mm from the root apex. Sodium hypochlorite at 5.25% and 6% was the only irrigating solution for which there is scientifi c evidence of root wall cleaning activity. Conclusions: Addition of ultrasound improved the cleaning potency of irrigant solutions. Isthmus regions had the lowest percentages of area free from debris.Item Detection of apical inflammatory root resorption associated with periapical lesion using different methods(2014) Estrela, Carlos; Guedes, Orlando Aguirre; Rabelo, Luiz Eduardo Gregoris; Decurcio, Daniel de Almeida; Alencar, Ana Helena Gonçalves de; Estrela, Cyntia Rodrigues de Araújo; Figueiredo, Jose Antonio Poli deThe 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.Item Detection of procedural errors during root canal preparation with stainless steel and nickel-titanium instruments by undergraduate students using periapical radiograph and cone beam computed tomography(2013) Alves, Regis Augusto Aleixo; Souza, João Batista de; Alencar, Ana Helena Gonçalves de; Pécora, Jesus Djalma; Estrela, CarlosIntroduction: This study investigated procedural errors made during root canal preparation using stainless steel and nickel-titanium (NiTi) instruments by undergraduate students, using two diagnostic imaging methods. Materials and Methods: Sixty human molars were divided into three groups (n=20; group 1: K-Flexofile, group 2: K3, and group 3: BioRace). The root canals were filled with gutta-percha and AH Plus. Periapical radiographs and cone beam computed tomography (CBCT) images were obtained to detect procedural errors made by undergraduate students during root canal preparation. Two examiners evaluated the presence or absence of fractured instruments, perforations and canal transportations. The agreement between observers was assessed using the kappa coefficient. The Kolmogorov-Smirnov, Fisher exact, ANOVA and Tukey tests were used for statistical analysis. The level of significance was set at 5%. Results: There were no significant differences in detecting procedural errors between two- and three-dimensional diagnostic imaging methods. There were no significant differences in procedural errors between stainless steel and NiTi instruments. Mean preparation time was recorded in minutes, and results were significantly different between the three groups. NiTi instruments had the lowest mean preparation time. Conclusion: Both periapical radiographs and CBCT identified procedural errors, however, three-dimensional images offered more diagnostic resources. The frequency of procedural errors was low for any of the endodontic instruments despite being used by inexperienced operators.Item Detection of root canal isthmuses in molars by map-reading dynamic using CBCT images(2013) Pecora, Jesus Djalma; Estrela, Carlos; Bueno, Mike dos Reis; Porto, Olavo Cesar Lyra; Alencar, Ana Helena Gonçalves de; Sousa Neto, Manoel Damiao de; Estrela, Cyntia Rodrigues de AraújoThe aim of this study was to detect root isthmuses in maxillary and mandibular molars and evaluate their frequencies using map-reading dynamics in CBCT images. Two hundred extracted human maxillary and mandibular molars were used in ex vivo assay. A consecutive sample of two hundred maxillary and mandibular molars (first and second) was selected from CBCT exams. The isthmuses were detected from the pulp orifice to the apex and were recorded according to their beginning and their end, into categories: 1. begin and end in cervical third; 2. beginning in cervical third and end in middle third; 3. beginning in cervical third and end in apical third; 4. beginning and end in middle third; 5. begin in middle third and end in apical third; 6. beginning and end in apical third; 7. no isthmus. The scans were obtained in different planes with map-reading in axial slices of 0.5 mm/0.5 mm involved the coronal to apical direction. The frequencies of isthmus were analyzed according to the level of root and evaluated by Chi-square test. The level of significance was set at α=0.05. The presence of isthmus detected in maxillary molars was 86% in ex vivo assay and 62% in vivo assay, whereas in mandibular molars was observed 70% in ex vivo assay and 72% in vivo assay. The frequency of isthmus was high in both study models. The map-reading dynamics in CBCT images was found to be precise to detect the localization of isthmus.
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