American Journal of Orthodontics and Dentofacial Orthopedics, 2005
The orthodontic treatment of an adult patient with a skeletal Class III malocclusion, increased a... more The orthodontic treatment of an adult patient with a skeletal Class III malocclusion, increased anterior facial height, negative overjet, and bilateral posterior crossbite is presented. Treatment options included mandibular first premolar or third molar extractions with dentoalveolar compensation or combined surgicalorthodontic treatment. Mandibular third molar extraction with dentoalveolar compensation was the treatment choice. Biofunctional brackets, with accentuated lingual crown torque on the maxillary incisors and accentuated buccal crown torque on the mandibular incisors, were used. The anterior crossbite was corrected with intermaxillary elastics from the palatal aspect of the maxillary incisors to the labial aspect of the mandibular incisors. Class III elastics moved the maxillary teeth mesially and assisted in retruding the mandibular teeth. Patient compliance with the elastics was excellent, and satisfactory dentofacial esthetics were achieved. This treatment protocol has rigorous indications, and it is not a routine plan. The mechanotherapy and the pros and cons of this approach are discussed. (Am J Orthod Dentofacial Orthop 2005;128:787-94)
Duchenne Muscular Dystrophy (DMD) is a genetic disorder with clinical signs of muscular weaknesse... more Duchenne Muscular Dystrophy (DMD) is a genetic disorder with clinical signs of muscular weaknesses and progressive atrophy. Golden Retriever dogs show similar genotypic and phenotypic characteristics to Human Muscular Dystrophy and are considered a proper animal model for DMD studies. Latero-lateral and dorso-ventral thoracic radiographies were obtained from 10 Golden Retriever dogs affected by muscular dystrophy, to investigate possible radiographic alterations. Thorax radiographic examination revealed (a) interstitial and alveolar pattern, (b) initial phases of pneumonia and pulmonary edema, (c) cardiomegaly as a principal alteration in the thoracic cavity, (d) megaesophagus displacing the trachea and heart silhouette, and (e) cranial protrusion of the diaphragm lining into the thorax with development of a hiatus hernia displacing the stomach to the caudal mediastinum. Postmortem examination showed pleural effusion, pulmonary emphysema, degenerative and metaplasic processes in the diaphragm and intercostal muscles. Radiographic examination was considered essential for the diagnosis of cardiac and respiratory disease in Golden Retriever dogs affected by muscular dystrophy, and to identify the primary pulmonary process and to provide the establishment of suitable therapeutic treatment, with a reserved prognosis in advanced stage of the disease.
Pulmonary function evaluation in dogs can be gotten by scintigraphy exams, which are obtained wit... more Pulmonary function evaluation in dogs can be gotten by scintigraphy exams, which are obtained with radiopharmacs injections, followed by radiography. In this study it was used 10 healthful male dogs of Rottweiler breed, radiographically normal and serum negative for dirofilariasis, with administration of varied doses of human serum albumin grouped marked with technetium-99m (MAA). The results were evaluated qualitatively and quantitatively, considering the index of pulmonary perfusion and its homogeneity, being found an increase on the homogeneity of image directly related with the number of MAA particles injected. This study defines the criteria of normality and the dosage of pulmonary perfusion in healthful dogs established with scintigraphy technique.
Duchenne muscular dystrophy (DMD) is one type of human's muscular dystrophy characterized by a ge... more Duchenne muscular dystrophy (DMD) is one type of human's muscular dystrophy characterized by a genetic disorder linked to the X chromosome. The Golden Retriever muscular dystrophic (GRMD) has been extensively studied and considered the best resembling model to the human disease. Therefore, for identifying internal organs abnormality in GRMD, abdominal and pelvic ultrasonography was performed in 24 golden retriever dogs, either healthy or muscular dystrophic in different levels of disease. The GRMD ultrasonographic exams diagnosed moderate to severe liver enlargement, including hepatic vessels and their branches and increase of echogenicity in gallbladder and urinary bladder. However was not-clearly recognized pathologic images from spleen and aortic vessels were accessed. Therefore, we believe, the ultrasonographic exam was an useful procedure to the assessment of abdominal organs in dogs affected by muscular dystrophy.
... THE ENERGY RESOLUTION AND WINDOW AREA CAPABILITIES OF THE GAS PROPORTIONALSCINTILLATION COUNT... more ... THE ENERGY RESOLUTION AND WINDOW AREA CAPABILITIES OF THE GAS PROPORTIONALSCINTILLATION COUNTER M. Alice,F. Alves, AJPLPolicarpo and ... capacitance play no role on thebehaviour of the gas pro-portional scintillation counter, it is expec-ted that ...
Introduction: Bacterial biofilm communities established in the apical part of infected root canal... more Introduction: Bacterial biofilm communities established in the apical part of infected root canals are conceivably of utmost importance in the pathogenesis of apical periodontitis. This study investigated the diversity of the apical endodontic microbiota by using cryopulverized root segments and massive parallel pyrosequencing analysis. Methods: Ten extracted teeth with attached apical periodontitis lesions were sectioned to obtain 2 root fragments (apical and middle/coronal segments). Apical root fragments were cryogenically ground, and DNA was extracted from samples and subjected to multiplex tag-encoded FLXtitanium amplicon pyrosequencing. Results: Pyrosequencing analysis yielded partial 16S rRNA gene sequences that were taxonomically classified into 187 bacterial species-level phylotypes (at 3% divergence), 84 genera, and 10 phyla. The most represented, abundant, and prevalent phyla were Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria, and Actinobacteria. The majority of species-level phylotypes occurred at low levels. The mean number of species-level phylotypes per sample was 37 (range, 13-80). A great interindividual variation in the composition of the apical microbiota was disclosed. Conclusions: This study extensively describes the diversity of the bacterial communities present selectively in the apical part of root canals of teeth with apical periodontitis and revealed a previously unanticipated high bacterial diversity. (J Endod 2011;37:1499-1503
Introduction: This in vitro study aimed to investigate the antibacterial effects of photodynamic ... more Introduction: This in vitro study aimed to investigate the antibacterial effects of photodynamic therapy (PDT) with methylene blue (MB) or toluidine blue (TB) (both at 15 mg/mL) as a supplement to instrumentation/irrigation of root canals experimentally contaminated with Enterococcus faecalis. Methods: Seventy extracted teeth had their root canals contaminated with an endodontic strain of E. faecalis for 7 days, instrumented with nickel-titanium instruments and irrigated either with 2.5% NaOCl or with 0.85% NaCl, and then randomly distributed into four experimental groups: MB/NaOCl (PDT with MB and NaOCl as the irrigant), TB/NaOCl (PDT with TB and NaOCl as the irrigant), MB/NaCl (PDT with MB and NaCl as the irrigant), and TB/NaCl (PDT with TB and NaCl as the irrigant). For PDT, the photosensitizer remained in the canal for 2 minutes before exposed to red light emitted from a diode laser for 4 minutes. Samples were taken before and after instrumentation/irrigation and following the specific PDT procedure for each group, plated onto Mitis-salivarius agar and the colony forming units counted. Results: Regardless of the irrigant used (NaOCl or NaCl), instrumentation significantly reduced bacterial counts in comparison to the baseline (p < 0.001). NaOCl as the irrigant was significantly more effective than NaCl, and this difference persisted after PDT, irrespective of the photosensitizer used (p < 0.05). PDT with either MB or TB did not significantly enhance disinfection after chemomechanical preparation using NaOCl as irrigant (p > 0.05). No significant differences were observed between the two photosensitizers (p > 0.05). Conclusion: These in vitro results suggest that PDT with either MB or TB may not exert a significant supplemental effect to instrumentation/irrigation procedures with regard to intracanal disinfection. Further adjustments in the PDT protocol may be required to enhance predictability in bacterial elimination before clinical use is recommended. (J Endod 2009;-:1-5)
Introduction: Oval-shaped root canals might represent a great challenge for proper disinfection. ... more Introduction: Oval-shaped root canals might represent a great challenge for proper disinfection. This study compared the capability of a newly developed instrument, the self-adjusting file (SAF), and rotary nickeltitanium (NiTi) instrumentation to eliminate Enterococcus faecalis populations from long oval root canals of extracted human teeth. As a secondary purpose, the ability of a modification in sampling technique to recover bacteria lodged in recesses of oval canals was evaluated. Methods: Long oval canals from mandibular incisors and maxillary second premolars were infected with E. faecalis (ATCC 29212) for 30 days and then randomly distributed into 2 experimental groups. In group 1, canals were prepared up to a 40/04 rotary BioRaCe instrument by using irrigation with NaviTip needles; in group 2, canals were prepared by using the SAF system with continuous irrigation. NaOCl and ethylenediaminetetraacetic acid were used as irrigants. Bacteriologic samples were taken before (S1) and after preparation (S2a and S2b). Results: Reduction in the bacterial populations was highly significant in both groups (P < .001). Preparation of long oval canals with the SAF was significantly more effective than rotary NiTi instrumentation in reducing intracanal E. faecalis counts (P = .01). Frequency of positive cultures in S2 samples was 11 of 20 (55%) for rotary instrumentation and 4 of 20 (20%) for SAF instrumentation (P = .048). S2b samples (modified method) yielded more positive samples than S2a (12/40 vs 5/40), but this difference reached no statistical significance (P > .05). Conclusions: The SAF system was significantly more effective than rotary NiTi instrumentation used with syringe/needle irrigation in disinfecting long oval root canals in vitro. A modified sampling technique might be necessary for oval canals. (J Endod 2010;36:1860-1865
Bacteria located at the apical part of infected root canals are arguably directly involved in the... more Bacteria located at the apical part of infected root canals are arguably directly involved in the pathogenesis of apical periodontitis. This study was conducted to profile and further compare the bacterial communities established at the apical and middle/coronal segments of infected root canals. Extracted teeth with attached apical periodontitis lesions were sectioned so as to obtain two root fragments representing the apical third and the coronal two thirds. Root fragments were subjected to a cryogenic grinding approach. DNA was extracted from root powder samples and used as a template for bacterial community profiling using a 16S ribosomal RNA gene-based seminested polymerase chain reaction/denaturing gradient gel electrophoresis approach. The mean number of bands in apical samples from teeth with primary infections was 28, ranging from 18 to 48, whereas in the middle/coronal samples, it was also 28, ranging from 19 to 36. Findings showed that the profile of bacterial community colonizing the apical third of infected root canals is as diverse as that occurring at the middle/coronal thirds. A high variability was observed for both interindividual (samples from the same region but from different patients) and intraindividual (samples from different regions of the same tooth) comparisons. The methodology used to prepare and analyze samples was highly effective in disclosing a previously unanticipated broad diversity of endodontic bacterial communities, especially at the apical part of infected root canals. (J Endod 2009;35:486-492)
Introduction: This study compared the ability of different approaches to supplement the antibacte... more Introduction: This study compared the ability of different approaches to supplement the antibacterial effects of chemomechanical preparation in ovalshaped root canals. Methods: Long oval canals from extracted teeth infected with Enterococcus faecalis (ATCC 29212) were chemomechanically prepared up to a 40/04 rotary BioRaCe instrument using 2.5% NaOCl irrigation and then subjected to two supplementary protocols. In the passive ultrasonic irrigation (PUI)/ chlorhexidine (CHX) group, canals were subjected to PUI for the activation of NaOCl followed by a final rinse with 0.2% CHX digluconate solution. In the Hedstr€ om group, canals received additional Hedstr€ om filing directed towards the buccal and lingual canal recesses. Bacteriological samples were taken before and after preparation, after PUI or Hedstr€ om instrumentation, and after CHX final rinsing. Results: Chemomechanical preparation and the supplementary steps promoted a highly significant bacterial reduction (P < .001). Quantitative (reduction in levels) and qualitative (frequency of negative cultures) analyses showed that PUI alone or Hedstr€ om filing did not significantly increase bacterial reduction (P > .05). Further rinsing with CHX also failed to significantly increase bacterial elimination when compared with post-PUI samples. However, the cumulative antibacterial effects of PUI and CHX final rinse were effective in significantly reducing bacterial counts to levels below those achieved after preparation (P = .03). This combined PUI/CHX approach also resulted in a significant increase in the incidence of negative cultures (P = .04). Conclusions: Findings suggest that there may be a benefit of using the PUI for the activation of NaOCl followed by a final rinse with CHX as supplementary steps in the treatment of infected oval-shaped root canals. (J Endod 2011;37:496-501)
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2005
Introduction: This cross-sectional study determined the prevalence of apical periodontitis in 108... more Introduction: This cross-sectional study determined the prevalence of apical periodontitis in 1086 root canal-treated teeth from an urban Colombian population and evaluated the association of several factors with the periradicular status. Methods: Periapical radiographs were used for analyses, and teeth were classified as healthy or diseased according to the periradicular status. Other factors were also evaluated for their association with the periradicular conditions, including gender, quality of both endodontic treatment and coronal restoration, apical level of filling, and presence of post restoration. Results: Fifty-one percent of the treated teeth were classified as healthy. Only 33% of the teeth had endodontic treatment rated as adequate. The quality of both endodontic treatment and coronal restoration significantly influenced the periradicular conditions (P < .001). Combined data revealed that teeth with both adequate endodontic treatment and adequate restorations showed significantly better periradicular status than the other combinations (P < .01), except for teeth with adequate treatment and inadequate restoration (P = .08). Canals filled up to 0-2 mm short of the apex had a significantly higher number of teeth rated as healthy than overfilled or underfilled cases (P = .02). Regression analysis showed that the quality of endodontic treatment was the most significant factor influencing the periradicular status (P < .001). Gender and presence of post restoration had no association with the periradicular conditions. Conclusions: Data from this Colombian population showed a relatively high prevalence of apical periodontitis in root canal-treated teeth. This was largely due to an equally high prevalence of treatments performed under substandard technical quality. The quality of the endodontic treatment was the most determinant factor for healthy periradicular status. (J Endod 2013;39:600-604)
The aim of this study was to compare the bacterial community profiles of the root canal microbiot... more The aim of this study was to compare the bacterial community profiles of the root canal microbiota associated with chronic apical periodontitis from Brazilian and Norwegian patients using the denaturing gradient gel electrophoresis (DGGE) and the ribosomal intergenic spacer analysis (RISA) approaches. DNA extracted from root canal samples was subjected to polymerase chain reaction using primers appropriate for further DGGE or RISA analysis. The resulting banding patterns representative of the bacterial community structures in samples from the two locations were compared. DGGE and RISA fingerprints showed a great interindividual variability in the bacterial community profiles, irrespective of the geographic location of the patient. However, similarities among the bacterial community DGGE profiles revealed the existence of a geography-related pattern. (J Endod 2008;34:1457-1461
Introduction: Bacteria located in the apical root canal system potentially participate in the pat... more Introduction: Bacteria located in the apical root canal system potentially participate in the pathogenesis of apical periodontitis. Detection and identification of apical bacteria can be compromised because of limitations in conventional sampling and identification procedures. This study identified several bacterial taxa in the apical and middle/coronal segments of primarily infected root canal system by using pulverized root segments and a culture-independent molecular method. Methods: Seventeen extracted teeth with attached apical periodontitis lesions were sectioned to obtain 2 root fragments (apical and middle/coronal segments). Root fragments were cryogenically ground, and DNA was extracted from samples. After multiple displacement amplification, DNA from samples was used as template in a reverse-capture checkerboard hybridization assay targeting 28 bacterial taxa. Results: Bacterial DNA was detected in all samples. The most prevalent taxa in the apical root canal system were Olsenella uli (76.5%), Prevotella baroniae (71%), Porphyromonas endodontalis (65%), Fusobacterium nucleatum (53%), and Tannerella forsythia (47%). O. uli, P. endodontalis, and Propionibacterium acnes were as frequently detected in apical samples as they were in middle/coronal samples. P. baroniae, T. forsythia, and F. nucleatum were found more frequently in the apical part of the canal as compared with matched coronal segments. Streptococcus species were more prevalent in middle/coronal samples. The median and mean of shared bacterial taxa between matched apical and middle/coronal segments were 27% and 41%, respectively. Conclusions: Several candidate endodontic pathogens were very prevalent in the apical root canal system. The apical microbiota was usually complex and differed in species composition when compared with the microbiota of middle/coronal samples from the same tooth. (J Endod 2010;36: 1617-1621
Bacteria located at the apical portion of the root canals are conceivably in a strategic position... more Bacteria located at the apical portion of the root canals are conceivably in a strategic position to induce damage to the periradicular tissues and resulting inflammatory diseases. This study sought to investigate the prevalence of 11 selected putative endodontic pathogens in the apical third of infected root canals associated with periradicular lesions. The apical root portion of 23 extracted teeth with carious pulpal exposures and attached periradicular lesions was sectioned, and the root canals were sampled for microbiological investigation. DNA was extracted from the samples and analyzed for the presence of 11 bacterial species using a nested polymerase chain reaction assay. The results showed that Pseuramibacter alactolyticus occurred in 10 cases (44%), Treponema denticola in 6 (26%), Fusobacterium nucleatum in 6 (26%), Porphyromonas endodontalis in 4 (17%), Filifactor alocis in 2 (9%), Dialister pneumosintes in 1 (4%), Porphyromonas gingivalis in 1 (4%), and Tannerella forsythensis in 1 (4%). No sample yielded Prevotella intermedia, Prevotella nigrescens, or Campylobacter rectus. Of the samples examined, 17 were positive for at least 1 of the target species. Occurrence of these bacterial species in the apical third of infected root canals suggests that they can be involved in causation of periradicular lesions.
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2009
Objective. Bacteria settled in the apical root canal are in a privileged position to inflict dama... more Objective. Bacteria settled in the apical root canal are in a privileged position to inflict damage to the periradicular tissues. Therefore, the species identified in this region can be of special relevance for the pathogenesis of apical periodontitis. This study investigated the occurrence and levels of several bacterial taxa in the apical root canal of teeth with apical periodontitis. Study design. DNA extracts from samples taken from the apical part of the root canal of extracted teeth evincing chronic apical periodontitis lesions served as templates for analysis of the presence and levels of 28 bacterial species/ phylotypes using a 16S ribosomal RNA gene-based reverse-capture checkerboard hybridization assay. Results. Bacterial DNA was detected in 19 out of 20 samples. Detected taxa included Pseudoramibacter alactolyticus (32%), Bacteroidetes clone X083 (26%), Streptococcus species (21%), Olsenella uli (10.5%), Synergistes clone BA121 (10.5%), Fusobacterium nucleatum (10.5%), Porphyromonas endodontalis (10.5%), Dialister clone BS016 (5%), Filifactor alocis (5%), Parvimonas micra (5%), and Treponema denticola (5%). Of these, only Bacteroidetes clone X083 and Synergistes clone BA121 were found at levels above 10 5 . Conclusion. Occurrence of these bacterial taxa in the apical part of infected root canals indicates their potential pathogenetic role in the etiology of apical periodontitis. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 107:721-726) Supported by grants 470417/2004-8, 300693/2005-2, and 304552/ 2006-2, from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), a Brazilian governmental institution.
American Journal of Orthodontics and Dentofacial Orthopedics, 2005
The orthodontic treatment of an adult patient with a skeletal Class III malocclusion, increased a... more The orthodontic treatment of an adult patient with a skeletal Class III malocclusion, increased anterior facial height, negative overjet, and bilateral posterior crossbite is presented. Treatment options included mandibular first premolar or third molar extractions with dentoalveolar compensation or combined surgicalorthodontic treatment. Mandibular third molar extraction with dentoalveolar compensation was the treatment choice. Biofunctional brackets, with accentuated lingual crown torque on the maxillary incisors and accentuated buccal crown torque on the mandibular incisors, were used. The anterior crossbite was corrected with intermaxillary elastics from the palatal aspect of the maxillary incisors to the labial aspect of the mandibular incisors. Class III elastics moved the maxillary teeth mesially and assisted in retruding the mandibular teeth. Patient compliance with the elastics was excellent, and satisfactory dentofacial esthetics were achieved. This treatment protocol has rigorous indications, and it is not a routine plan. The mechanotherapy and the pros and cons of this approach are discussed. (Am J Orthod Dentofacial Orthop 2005;128:787-94)
Duchenne Muscular Dystrophy (DMD) is a genetic disorder with clinical signs of muscular weaknesse... more Duchenne Muscular Dystrophy (DMD) is a genetic disorder with clinical signs of muscular weaknesses and progressive atrophy. Golden Retriever dogs show similar genotypic and phenotypic characteristics to Human Muscular Dystrophy and are considered a proper animal model for DMD studies. Latero-lateral and dorso-ventral thoracic radiographies were obtained from 10 Golden Retriever dogs affected by muscular dystrophy, to investigate possible radiographic alterations. Thorax radiographic examination revealed (a) interstitial and alveolar pattern, (b) initial phases of pneumonia and pulmonary edema, (c) cardiomegaly as a principal alteration in the thoracic cavity, (d) megaesophagus displacing the trachea and heart silhouette, and (e) cranial protrusion of the diaphragm lining into the thorax with development of a hiatus hernia displacing the stomach to the caudal mediastinum. Postmortem examination showed pleural effusion, pulmonary emphysema, degenerative and metaplasic processes in the diaphragm and intercostal muscles. Radiographic examination was considered essential for the diagnosis of cardiac and respiratory disease in Golden Retriever dogs affected by muscular dystrophy, and to identify the primary pulmonary process and to provide the establishment of suitable therapeutic treatment, with a reserved prognosis in advanced stage of the disease.
Pulmonary function evaluation in dogs can be gotten by scintigraphy exams, which are obtained wit... more Pulmonary function evaluation in dogs can be gotten by scintigraphy exams, which are obtained with radiopharmacs injections, followed by radiography. In this study it was used 10 healthful male dogs of Rottweiler breed, radiographically normal and serum negative for dirofilariasis, with administration of varied doses of human serum albumin grouped marked with technetium-99m (MAA). The results were evaluated qualitatively and quantitatively, considering the index of pulmonary perfusion and its homogeneity, being found an increase on the homogeneity of image directly related with the number of MAA particles injected. This study defines the criteria of normality and the dosage of pulmonary perfusion in healthful dogs established with scintigraphy technique.
Duchenne muscular dystrophy (DMD) is one type of human's muscular dystrophy characterized by a ge... more Duchenne muscular dystrophy (DMD) is one type of human's muscular dystrophy characterized by a genetic disorder linked to the X chromosome. The Golden Retriever muscular dystrophic (GRMD) has been extensively studied and considered the best resembling model to the human disease. Therefore, for identifying internal organs abnormality in GRMD, abdominal and pelvic ultrasonography was performed in 24 golden retriever dogs, either healthy or muscular dystrophic in different levels of disease. The GRMD ultrasonographic exams diagnosed moderate to severe liver enlargement, including hepatic vessels and their branches and increase of echogenicity in gallbladder and urinary bladder. However was not-clearly recognized pathologic images from spleen and aortic vessels were accessed. Therefore, we believe, the ultrasonographic exam was an useful procedure to the assessment of abdominal organs in dogs affected by muscular dystrophy.
... THE ENERGY RESOLUTION AND WINDOW AREA CAPABILITIES OF THE GAS PROPORTIONALSCINTILLATION COUNT... more ... THE ENERGY RESOLUTION AND WINDOW AREA CAPABILITIES OF THE GAS PROPORTIONALSCINTILLATION COUNTER M. Alice,F. Alves, AJPLPolicarpo and ... capacitance play no role on thebehaviour of the gas pro-portional scintillation counter, it is expec-ted that ...
Introduction: Bacterial biofilm communities established in the apical part of infected root canal... more Introduction: Bacterial biofilm communities established in the apical part of infected root canals are conceivably of utmost importance in the pathogenesis of apical periodontitis. This study investigated the diversity of the apical endodontic microbiota by using cryopulverized root segments and massive parallel pyrosequencing analysis. Methods: Ten extracted teeth with attached apical periodontitis lesions were sectioned to obtain 2 root fragments (apical and middle/coronal segments). Apical root fragments were cryogenically ground, and DNA was extracted from samples and subjected to multiplex tag-encoded FLXtitanium amplicon pyrosequencing. Results: Pyrosequencing analysis yielded partial 16S rRNA gene sequences that were taxonomically classified into 187 bacterial species-level phylotypes (at 3% divergence), 84 genera, and 10 phyla. The most represented, abundant, and prevalent phyla were Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria, and Actinobacteria. The majority of species-level phylotypes occurred at low levels. The mean number of species-level phylotypes per sample was 37 (range, 13-80). A great interindividual variation in the composition of the apical microbiota was disclosed. Conclusions: This study extensively describes the diversity of the bacterial communities present selectively in the apical part of root canals of teeth with apical periodontitis and revealed a previously unanticipated high bacterial diversity. (J Endod 2011;37:1499-1503
Introduction: This in vitro study aimed to investigate the antibacterial effects of photodynamic ... more Introduction: This in vitro study aimed to investigate the antibacterial effects of photodynamic therapy (PDT) with methylene blue (MB) or toluidine blue (TB) (both at 15 mg/mL) as a supplement to instrumentation/irrigation of root canals experimentally contaminated with Enterococcus faecalis. Methods: Seventy extracted teeth had their root canals contaminated with an endodontic strain of E. faecalis for 7 days, instrumented with nickel-titanium instruments and irrigated either with 2.5% NaOCl or with 0.85% NaCl, and then randomly distributed into four experimental groups: MB/NaOCl (PDT with MB and NaOCl as the irrigant), TB/NaOCl (PDT with TB and NaOCl as the irrigant), MB/NaCl (PDT with MB and NaCl as the irrigant), and TB/NaCl (PDT with TB and NaCl as the irrigant). For PDT, the photosensitizer remained in the canal for 2 minutes before exposed to red light emitted from a diode laser for 4 minutes. Samples were taken before and after instrumentation/irrigation and following the specific PDT procedure for each group, plated onto Mitis-salivarius agar and the colony forming units counted. Results: Regardless of the irrigant used (NaOCl or NaCl), instrumentation significantly reduced bacterial counts in comparison to the baseline (p < 0.001). NaOCl as the irrigant was significantly more effective than NaCl, and this difference persisted after PDT, irrespective of the photosensitizer used (p < 0.05). PDT with either MB or TB did not significantly enhance disinfection after chemomechanical preparation using NaOCl as irrigant (p > 0.05). No significant differences were observed between the two photosensitizers (p > 0.05). Conclusion: These in vitro results suggest that PDT with either MB or TB may not exert a significant supplemental effect to instrumentation/irrigation procedures with regard to intracanal disinfection. Further adjustments in the PDT protocol may be required to enhance predictability in bacterial elimination before clinical use is recommended. (J Endod 2009;-:1-5)
Introduction: Oval-shaped root canals might represent a great challenge for proper disinfection. ... more Introduction: Oval-shaped root canals might represent a great challenge for proper disinfection. This study compared the capability of a newly developed instrument, the self-adjusting file (SAF), and rotary nickeltitanium (NiTi) instrumentation to eliminate Enterococcus faecalis populations from long oval root canals of extracted human teeth. As a secondary purpose, the ability of a modification in sampling technique to recover bacteria lodged in recesses of oval canals was evaluated. Methods: Long oval canals from mandibular incisors and maxillary second premolars were infected with E. faecalis (ATCC 29212) for 30 days and then randomly distributed into 2 experimental groups. In group 1, canals were prepared up to a 40/04 rotary BioRaCe instrument by using irrigation with NaviTip needles; in group 2, canals were prepared by using the SAF system with continuous irrigation. NaOCl and ethylenediaminetetraacetic acid were used as irrigants. Bacteriologic samples were taken before (S1) and after preparation (S2a and S2b). Results: Reduction in the bacterial populations was highly significant in both groups (P < .001). Preparation of long oval canals with the SAF was significantly more effective than rotary NiTi instrumentation in reducing intracanal E. faecalis counts (P = .01). Frequency of positive cultures in S2 samples was 11 of 20 (55%) for rotary instrumentation and 4 of 20 (20%) for SAF instrumentation (P = .048). S2b samples (modified method) yielded more positive samples than S2a (12/40 vs 5/40), but this difference reached no statistical significance (P > .05). Conclusions: The SAF system was significantly more effective than rotary NiTi instrumentation used with syringe/needle irrigation in disinfecting long oval root canals in vitro. A modified sampling technique might be necessary for oval canals. (J Endod 2010;36:1860-1865
Bacteria located at the apical part of infected root canals are arguably directly involved in the... more Bacteria located at the apical part of infected root canals are arguably directly involved in the pathogenesis of apical periodontitis. This study was conducted to profile and further compare the bacterial communities established at the apical and middle/coronal segments of infected root canals. Extracted teeth with attached apical periodontitis lesions were sectioned so as to obtain two root fragments representing the apical third and the coronal two thirds. Root fragments were subjected to a cryogenic grinding approach. DNA was extracted from root powder samples and used as a template for bacterial community profiling using a 16S ribosomal RNA gene-based seminested polymerase chain reaction/denaturing gradient gel electrophoresis approach. The mean number of bands in apical samples from teeth with primary infections was 28, ranging from 18 to 48, whereas in the middle/coronal samples, it was also 28, ranging from 19 to 36. Findings showed that the profile of bacterial community colonizing the apical third of infected root canals is as diverse as that occurring at the middle/coronal thirds. A high variability was observed for both interindividual (samples from the same region but from different patients) and intraindividual (samples from different regions of the same tooth) comparisons. The methodology used to prepare and analyze samples was highly effective in disclosing a previously unanticipated broad diversity of endodontic bacterial communities, especially at the apical part of infected root canals. (J Endod 2009;35:486-492)
Introduction: This study compared the ability of different approaches to supplement the antibacte... more Introduction: This study compared the ability of different approaches to supplement the antibacterial effects of chemomechanical preparation in ovalshaped root canals. Methods: Long oval canals from extracted teeth infected with Enterococcus faecalis (ATCC 29212) were chemomechanically prepared up to a 40/04 rotary BioRaCe instrument using 2.5% NaOCl irrigation and then subjected to two supplementary protocols. In the passive ultrasonic irrigation (PUI)/ chlorhexidine (CHX) group, canals were subjected to PUI for the activation of NaOCl followed by a final rinse with 0.2% CHX digluconate solution. In the Hedstr€ om group, canals received additional Hedstr€ om filing directed towards the buccal and lingual canal recesses. Bacteriological samples were taken before and after preparation, after PUI or Hedstr€ om instrumentation, and after CHX final rinsing. Results: Chemomechanical preparation and the supplementary steps promoted a highly significant bacterial reduction (P < .001). Quantitative (reduction in levels) and qualitative (frequency of negative cultures) analyses showed that PUI alone or Hedstr€ om filing did not significantly increase bacterial reduction (P > .05). Further rinsing with CHX also failed to significantly increase bacterial elimination when compared with post-PUI samples. However, the cumulative antibacterial effects of PUI and CHX final rinse were effective in significantly reducing bacterial counts to levels below those achieved after preparation (P = .03). This combined PUI/CHX approach also resulted in a significant increase in the incidence of negative cultures (P = .04). Conclusions: Findings suggest that there may be a benefit of using the PUI for the activation of NaOCl followed by a final rinse with CHX as supplementary steps in the treatment of infected oval-shaped root canals. (J Endod 2011;37:496-501)
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2005
Introduction: This cross-sectional study determined the prevalence of apical periodontitis in 108... more Introduction: This cross-sectional study determined the prevalence of apical periodontitis in 1086 root canal-treated teeth from an urban Colombian population and evaluated the association of several factors with the periradicular status. Methods: Periapical radiographs were used for analyses, and teeth were classified as healthy or diseased according to the periradicular status. Other factors were also evaluated for their association with the periradicular conditions, including gender, quality of both endodontic treatment and coronal restoration, apical level of filling, and presence of post restoration. Results: Fifty-one percent of the treated teeth were classified as healthy. Only 33% of the teeth had endodontic treatment rated as adequate. The quality of both endodontic treatment and coronal restoration significantly influenced the periradicular conditions (P < .001). Combined data revealed that teeth with both adequate endodontic treatment and adequate restorations showed significantly better periradicular status than the other combinations (P < .01), except for teeth with adequate treatment and inadequate restoration (P = .08). Canals filled up to 0-2 mm short of the apex had a significantly higher number of teeth rated as healthy than overfilled or underfilled cases (P = .02). Regression analysis showed that the quality of endodontic treatment was the most significant factor influencing the periradicular status (P < .001). Gender and presence of post restoration had no association with the periradicular conditions. Conclusions: Data from this Colombian population showed a relatively high prevalence of apical periodontitis in root canal-treated teeth. This was largely due to an equally high prevalence of treatments performed under substandard technical quality. The quality of the endodontic treatment was the most determinant factor for healthy periradicular status. (J Endod 2013;39:600-604)
The aim of this study was to compare the bacterial community profiles of the root canal microbiot... more The aim of this study was to compare the bacterial community profiles of the root canal microbiota associated with chronic apical periodontitis from Brazilian and Norwegian patients using the denaturing gradient gel electrophoresis (DGGE) and the ribosomal intergenic spacer analysis (RISA) approaches. DNA extracted from root canal samples was subjected to polymerase chain reaction using primers appropriate for further DGGE or RISA analysis. The resulting banding patterns representative of the bacterial community structures in samples from the two locations were compared. DGGE and RISA fingerprints showed a great interindividual variability in the bacterial community profiles, irrespective of the geographic location of the patient. However, similarities among the bacterial community DGGE profiles revealed the existence of a geography-related pattern. (J Endod 2008;34:1457-1461
Introduction: Bacteria located in the apical root canal system potentially participate in the pat... more Introduction: Bacteria located in the apical root canal system potentially participate in the pathogenesis of apical periodontitis. Detection and identification of apical bacteria can be compromised because of limitations in conventional sampling and identification procedures. This study identified several bacterial taxa in the apical and middle/coronal segments of primarily infected root canal system by using pulverized root segments and a culture-independent molecular method. Methods: Seventeen extracted teeth with attached apical periodontitis lesions were sectioned to obtain 2 root fragments (apical and middle/coronal segments). Root fragments were cryogenically ground, and DNA was extracted from samples. After multiple displacement amplification, DNA from samples was used as template in a reverse-capture checkerboard hybridization assay targeting 28 bacterial taxa. Results: Bacterial DNA was detected in all samples. The most prevalent taxa in the apical root canal system were Olsenella uli (76.5%), Prevotella baroniae (71%), Porphyromonas endodontalis (65%), Fusobacterium nucleatum (53%), and Tannerella forsythia (47%). O. uli, P. endodontalis, and Propionibacterium acnes were as frequently detected in apical samples as they were in middle/coronal samples. P. baroniae, T. forsythia, and F. nucleatum were found more frequently in the apical part of the canal as compared with matched coronal segments. Streptococcus species were more prevalent in middle/coronal samples. The median and mean of shared bacterial taxa between matched apical and middle/coronal segments were 27% and 41%, respectively. Conclusions: Several candidate endodontic pathogens were very prevalent in the apical root canal system. The apical microbiota was usually complex and differed in species composition when compared with the microbiota of middle/coronal samples from the same tooth. (J Endod 2010;36: 1617-1621
Bacteria located at the apical portion of the root canals are conceivably in a strategic position... more Bacteria located at the apical portion of the root canals are conceivably in a strategic position to induce damage to the periradicular tissues and resulting inflammatory diseases. This study sought to investigate the prevalence of 11 selected putative endodontic pathogens in the apical third of infected root canals associated with periradicular lesions. The apical root portion of 23 extracted teeth with carious pulpal exposures and attached periradicular lesions was sectioned, and the root canals were sampled for microbiological investigation. DNA was extracted from the samples and analyzed for the presence of 11 bacterial species using a nested polymerase chain reaction assay. The results showed that Pseuramibacter alactolyticus occurred in 10 cases (44%), Treponema denticola in 6 (26%), Fusobacterium nucleatum in 6 (26%), Porphyromonas endodontalis in 4 (17%), Filifactor alocis in 2 (9%), Dialister pneumosintes in 1 (4%), Porphyromonas gingivalis in 1 (4%), and Tannerella forsythensis in 1 (4%). No sample yielded Prevotella intermedia, Prevotella nigrescens, or Campylobacter rectus. Of the samples examined, 17 were positive for at least 1 of the target species. Occurrence of these bacterial species in the apical third of infected root canals suggests that they can be involved in causation of periradicular lesions.
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2009
Objective. Bacteria settled in the apical root canal are in a privileged position to inflict dama... more Objective. Bacteria settled in the apical root canal are in a privileged position to inflict damage to the periradicular tissues. Therefore, the species identified in this region can be of special relevance for the pathogenesis of apical periodontitis. This study investigated the occurrence and levels of several bacterial taxa in the apical root canal of teeth with apical periodontitis. Study design. DNA extracts from samples taken from the apical part of the root canal of extracted teeth evincing chronic apical periodontitis lesions served as templates for analysis of the presence and levels of 28 bacterial species/ phylotypes using a 16S ribosomal RNA gene-based reverse-capture checkerboard hybridization assay. Results. Bacterial DNA was detected in 19 out of 20 samples. Detected taxa included Pseudoramibacter alactolyticus (32%), Bacteroidetes clone X083 (26%), Streptococcus species (21%), Olsenella uli (10.5%), Synergistes clone BA121 (10.5%), Fusobacterium nucleatum (10.5%), Porphyromonas endodontalis (10.5%), Dialister clone BS016 (5%), Filifactor alocis (5%), Parvimonas micra (5%), and Treponema denticola (5%). Of these, only Bacteroidetes clone X083 and Synergistes clone BA121 were found at levels above 10 5 . Conclusion. Occurrence of these bacterial taxa in the apical part of infected root canals indicates their potential pathogenetic role in the etiology of apical periodontitis. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 107:721-726) Supported by grants 470417/2004-8, 300693/2005-2, and 304552/ 2006-2, from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), a Brazilian governmental institution.
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