Caio Ferraz - Academia.edu (original) (raw)

Papers by Caio Ferraz

Research paper thumbnail of Avaliação da capacidade de remoção da smear layer das paredes de canais instrumentados utilizando diferentes substancias quimicas auxiliares ao preparo quimico-mecanico

INTRODUÇÃO 2 REVISÃO DA LITERATURA 2.1 Considerações sobre a Smear Layer 2.2 Substâncias Químicas... more INTRODUÇÃO 2 REVISÃO DA LITERATURA 2.1 Considerações sobre a Smear Layer 2.2 Substâncias Químicas Auxiliares à remoção da smear layer. 2.3 Clorexidina como substância química auxiliar ao preparo químicomecânico. 3 PROPOSIÇÃO 4 MATERIAL E MÉTODOS 4.1 Seleção e coleta da amostra 4.2 Preparo químico-mecânico dos canais radiculares 4.3 Procedimento de clivagem 4.4 Análise em Microscopia Eletrônica de Varredura 4.5 Análise estatística 5 RESULTADOS 5.1 Dados obtidos após análise dos espécimes no TERÇO CERVICAL. X 5.2 Dados obtidos após análise dos espécimes no TERÇO MÉDIO 5.3 Dados obtidos após análise dos espécimes no TERÇO APICAL 5.4 Dados obtidos após análise dos espécimes considerando os terços cervical, médio e apical.

Research paper thumbnail of Estudo in vitro da atividade antimicrobiana imediata e mediata da clorexidina gel 2% usada como irrigante endodontico contra Enterococcus faecalis

CJJedíco e.sfe frt1bt1/ho, 9los meus país Üebaslíiio e 9tlaría 9ielena, pelo exemplo de lula e co... more CJJedíco e.sfe frt1bt1/ho, 9los meus país Üebaslíiio e 9tlaría 9ielena, pelo exemplo de lula e conquísla de um ideal pelo amor, carinho, ensinamento, afelo e dedicação que ílumínamm meus caminhos obscuros; pela renúncia de seus sonhos pam que eu pudesse realizar os meus. 9los meus aoós, cpedro, 9lnlônía, Carolina e 9luguslo (in memorian), pelo exemplo de comgem, perseoemnça e dignidade para enfrentar as dificuldades que tl oida nos impõe. 9t 8uliana pelo tlmor, carinho, pacíênda e lodo apoio pam lular por nosso ideal Vil Vl11 c5e vencemos, 9llguém esteve conosco. c5e nada conseguimos, ele conlínua junto a nós. c5e persíslínnos juntos, veremos realmente que Quem nos foz conlínuar sorrirá para nós, mesmo que CJJele, na folícídade, nós tenhamos esquecido. IX 9lo meu orientador cprof CJJr. Caio Cezar CJ(andi Cferraz 9l você, que quando deveria .ser .simplesmente professor, foi meu We.sfre, Que quando deveria .ser .simplesmente mestre, foi meu :llmigo e em .sua amizade me compreendeu e me incenfívou a .seguir meu caminho.

Research paper thumbnail of Apexification with a New Intra-Canal Medicament: A Multidisciplinary Case Report

iranian endodontic journal, 2012

Dental trauma generally requires multidisciplinary planning and treatment for good prognosis. Whe... more Dental trauma generally requires multidisciplinary planning and treatment for good prognosis. When immature teeth are traumatized to a degree where pulp necrosis ensues, the objective of root canal treatment should be apexogenesis and root maturation. Apexification of the root is the conventional choice, which involves cleaning the canal and filling it with a temporary medication that stimulates the formation of a calcific apical barrier. Dental Trauma Service of Piracicaba Dental School, State University of Campinas (UNICAMP), Brazil employs a dressing for apexification treatments with calcium hydroxide, chlorhexidine gel 2% and zinc oxide. This paper reports the case of a dental trauma of the maxillary central incisors and subluxation on teeth 11, 12 and 21 that were treated with multidisciplinary collaboration (Endodontics, Periodontology and Operative Dentistry) to improve prognosis. After five-years there were no pathological conditions and the teeth showed every evidences of s...

Research paper thumbnail of Evaluation of Endodontic Treatments Performed by Students in a Brazilian Dental School

Journal of Dental Education, 2005

The aims of this study were to evaluate the clinical outcomes of root canal treatments performed ... more The aims of this study were to evaluate the clinical outcomes of root canal treatments performed by final‐year students in the Dental School of Piracicaba, State University of Campinas, SP, Brazil, during the year 2000 and to evaluate the success rate of these treatments at follow‐ups conducted one and three years later (2001–03). All 579 endodontic treatments performed by final‐year students were selected for this investigation. Detailed personal and dental history was obtained from the patient's records. Clinical and radiographic follow‐up examinations were performed. For 78.8 percent of the cases, dental caries was recorded as the cause for performing endodontic treatment; for 8.8 percent, prosthetic reasons were given; and for 12.4 percent, failure of the endodontic treatment was the reason. The largest percentage (30.7 percent) of recalled patients was examined after one year; the success rate at this follow‐up evaluation ranged from 83 percent to 96 percent depending on th...

Research paper thumbnail of Treponema diversity in root canals with endodontic failure

European Journal of Dentistry, 2013

ABSTRACTObjective: This study sought to investigate the prevalence of eight oral Treponemas (Trep... more ABSTRACTObjective: This study sought to investigate the prevalence of eight oral Treponemas (Treponema denticola, T. amylovorum, T. maltophilum, T. medium, T. pectinovorum, T. socranskii, T. vicentii and T. lecithinolyticum) in teeth with endodontic treatment failure and periapical lesion.Methods: Samples were taken from 40 root canals presenting endodontic failure and periapical lesion. DNA extraction was performed and Nested-PCR technique was used for the detection of Treponema species using specific primers.Results: Treponemas was detected in 56.5% of the samples analyzed (22/39). Individual root canals yielded a maximum of 6 target Treponema species. T. denticola (30.8%) and T. maltophilum (30.8%) were the most frequently detected species followed by T. medium (20.5%), T. socranskii (20.5%), T. pectinovorum (17.9%) and T. vicentii (17.9%). Positive association was verified between T. denticola and T. maltophilum such as T. medium (P<.05). T. lecithinolyticum was positively as...

Research paper thumbnail of In Vitro Assessment of the Antimicrobial Action and the Mechanical Ability of Chlorhexidine Gel as an Endodontic Irrigant

Journal of Endodontics, 2001

The objective of this study was to assess the chlorhexidine gluconate gel as an endodontic irriga... more The objective of this study was to assess the chlorhexidine gluconate gel as an endodontic irrigant. First the ability of chlorhexidine gel to disinfect root canals contaminated in vitro with Enterococcus faecalis was investigated. A scanning electron microscope was also used to evaluate its cleansing ability compared with endodontic irrigants commonly used, such as sodium hypochlorite and chlorhexidine gluconate liquid. The results indicated that the chlorhexidine gel produced a cleaner root canal surface and had an antimicrobial ability comparable with that obtained with the other solutions tested. It was concluded that chlorhexidine gluconate in gel form has potential for use as an endodontic irrigant.

Research paper thumbnail of Antimicrobial and cytotoxic effects of phosphoric acid solution compared to other root canal irrigants

Journal of Applied Oral Science, 2015

P hosphoric acid has been suggested as an irrigant due to its effectiveness in removing the smear... more P hosphoric acid has been suggested as an irrigant due to its effectiveness in removing the smear layer. Objectives: The purpose of this study was to compare the antimicrobial and cytotoxic effects of a 37% phosphoric acid solution to other irrigants commonly used in endodontics. Material and Methods: The substances 37% phosphoric acid, 17% EDTA, 10% citric acid, 2% chlorhexidine (solution and gel), and 5.25% NaOCl were evaluated. The antimicrobial activity was tested against Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Actinomyces meyeri, Parvimonas micra, Porphyromonas gingivalis, and Prevotella nigrescens according to the agar diffusion method. The cytotoxicity of the irrigants was determined by using the MTT assay. Results: Phosphoric acid presented higher antimicrobial activity compared to the other tested irrigants. With regard to the cell viability, this solution showed results similar to those with 5.25% NaOCl and 2% chlorhexidine (gel and solution), whereas 17% EDTA and 10% citric acid showed higher cell viability compared to other irrigants. Conclusion: Phosphoric acid demonstrated higher antimicrobial activity and cytotoxicity similar to that of 5.25% NaOCl and 2% chlorhexidine (gel and solution).

Research paper thumbnail of Monitoring the effectiveness of root canal procedures on endotoxin levels found in teeth with chronic apical periodontitis

Journal of Applied Oral Science, 2014

The aim of this study was to monitor the effectiveness of root canal procedures by using differen... more The aim of this study was to monitor the effectiveness of root canal procedures by using different irrigants and intracanal medication on endotoxin levels found in root canals of teeth with chronic apical periodontitis. Material and methods: Thirty root canals of teeth with pulpal necrosis associated with periapical lesions were selected and randomly divided into groups according to the irrigants used: GI-2.5% NaOCl, GII-2% chlorhexidine (CHX) gel, and GIII-saline solution (SS) (all, n=10). Samples were collected with sterile/apyrogenic paper points before (S1) and after root canal instrumentation (S2), after use of 17% ethylenediaminetetraacetic acid (EDTA) (S3), and after 30 days of intracanal medication (Ca(OH)2+SS) (S4). A turbidimetric kinetic Limulus Amebocyte Lysate assay was used for endotoxin measurement. Results: Endotoxins were detected in 100% of the root canals investigated (30/30), with a median value of 18.70 EU/mL. After irrigant tested: 2.5% NaOCl (99.65%) (GI), 2% CHX (94.27%) (GII), and SS (96.79%) (GIII) (all p<0.05). Root canal rinse with 17% EDTA (S3) for a 3-minute period failed to decrease endotoxin levels in GI and a slight decrease was observed in GII (59%) and GIII residual endotoxins: 2.5% NaOCl (90%) (GI), 2% CHX (88.8%) (GII), and SS (85.7%) (GIII, p<0.05). No differences were found in the endotoxin reduction when comparing enduring root canal instrumentation for the endotoxin removal from root canals of teeth with chronic apical periodontitis. Moreover, the use of intracanal medication for 30 days contributed for an improvement of endotoxin reduction.

Research paper thumbnail of Chlorhexidine gel associated with papain in pulp tissue dissolution

Restorative Dentistry & Endodontics, 2013

Chlorhexidine gel associated with papain in pulp tissue dissolution Objectives: This study aimed ... more Chlorhexidine gel associated with papain in pulp tissue dissolution Objectives: This study aimed to evaluate the capacity of 2% chlorhexidine gel associated with 8% papain gel in comparison with 5.25% sodium hypochlorite in bovine pulp tissue dissolution. Materials and Methods: Ninety bovine pulps of standardized sizes were used and fragmented into 5-mm sizes. The fragments were removed from the root middle third region. They were divided into 6 experimental groups (n = 15), 1) 8% papain; 2) 2% chlorhexidine; 3) 2% chlorhexidine associated with 8% papain; 4) 0.9% saline solution; 5) 2.5% sodium hypochlorite; and 6) 5.25% sodium hypochlorite. The pulp fragments were weighed and put into immobile test tubes for dissolution for time intervals of 30, 60, 90, and 120 min. Results: The 5.25% sodium hypochlorite had greater dissolution potential than the pure papain, and when associated with chlorhexidine, both promoted greater dissolution than did the saline solution and 2% chlorhexidine groups (p < 0.05). The 2.5% sodium hypochlorite promoted dissolution to a lesser extent than the groups with papain within a period of 30 min (p < 0.05), but, was comparable to the saline solution and chlorhexidine. After 120 min, the 2.5% and 5.25% sodium hypochlorite promoted dissolution of 100% of the pulp fragments, and papain, 61%, while chlorhexidine associated with papain and chlorhexidine alone dissolved only 55% and 3%, respectively. Conclusions: The 8% papain in gel, both alone and in association with chlorhexidine, was able to dissolve bovine pulp tissue, but to a lesser extent than did 5.25% sodium hypochlorite.

Research paper thumbnail of Efficacy of ethylene-diamine-tetra-acetic acid associated with chlorhexidine on intracanal medication removal: A scanning electron microscopy study

Microscopy Research and Technique, 2014

The aim of this study was to evaluate the effectiveness of 17% ethylene-diamine-tetra-acetic acid... more The aim of this study was to evaluate the effectiveness of 17% ethylene-diamine-tetra-acetic acid (EDTA) used alone or associated with 2% chlorhexidine gel (CHX) on intracanal medications (ICM) removal. Sixty single-rooted human teeth with fully formed apex were selected. The cervical and middle thirds of each canal were prepared with Gates Glidden drills and rotary files. The apical third was shaped with hand files. The specimens were randomly divided into two groups depending on the ICM used after instrumentation: calcium hydroxide Ca(OH)(2) +CHX or Ca(OH)(2) +sterile saline (SS). After seven days, each group was divided into subgroups according to the protocol used for ICM removal: instrumentation and irrigation either with EDTA, CHX+EDTA, or SS (control groups). All specimens were sectioned and processed for observation of the apical thirds by using scanning electron microscopy. Two calibrated evaluators attributed scores to each specimen. The differences between the protocols for ICM removal were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Friedman and Wilcoxon signed rank tests were used for comparison between the score of debris obtained in each root canal third. Remains of Ca(OH)(2) were found in all specimens independently of the protocol and ICM used (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 0.05). Seventeen percent EDTA showed the best results in removing ICM when used alone…

Research paper thumbnail of Comparison of Endotoxin Levels in Previous Studies on Primary Endodontic Infections

Journal of Endodontics, 2011

Background: This study was performed to determine which of the quantitative methods, namely, chro... more Background: This study was performed to determine which of the quantitative methods, namely, chromogenic endpoint, chromogenic kinetic, and turbidimetric kinetic ones, best fit for the analysis of primary endodontic infections. Methods: Twenty-one root canals with apical periodontitis were sampled with paper points. The same sample was analyzed by means of the endpoint chromogenic Limulus amebocyte lysate (LAL) assay (QCL), quantitative kinetic chromogenic LAL assay (KQCL), and kinetic turbidimetric LAL assay (Turbidimetric). Results: All three LAL methods were effective in the recovery of endotoxin from root canal infection. Regardless of the method tested, endotoxin was detected in 100% of the root canals (21/21). The KQCL assay yielded a median value of endotoxin of 7.49 EU/ mL, close to and not significantly different from those for the turbidimetric test (9.19 EU/mL) (both kinetic methods) (p > 0.05). In contrast, the endpoint QCL showed a median value of 34.20 EU/mL (p < 0.05). The comparison of the three methods revealed that both turbidimetric and KQCL methods were more precise, with best reproducibility (the coefficient variation between analysis of the root canal and its duplicate was lower than 10%). The inhibition/enhancement assay indicated a good interaction between the root canal samples with the turbidimetric method. Conclusion: This study has revealed that quantitative kineticturbidimetric and kinetic-chromogenic LAL methods are best fitted for the analysis of endotoxins in root canal infection, both being more precise and allowing better reproducibility compared with the endpoint-QCL assay.

Research paper thumbnail of In vitro assessment of the immediate and prolonged antimicrobial action of chlorhexidine gel as an endodontic irrigant against Enterococcus faecalis

Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 2005

The aim of this study was to assess in vitro the antimicrobial activity of 2% chlorhexidine gel a... more The aim of this study was to assess in vitro the antimicrobial activity of 2% chlorhexidine gel against Enterococcus faecalis, comparing it to other endodontic irrigants (2% chlorhexidine liquid and 5.25% sodium hypochlorite). Study design. Eighty roots of human mandibular premolars were prepared by serial instrumentation technique, autoclaved, and contaminated for 7 days with E faecalis monocultures. The roots were then divided into 5 groups according to the irrigant substance used during the standardized biomechanical preparation. In order to evaluate the antimicrobial action of the irrigant substances, 3 microbial samples were taken: initial (before the biomechanical preparation); post-treatment (immediately after the biomechanical preparation), and final (7 days after the biomechanical preparation). The microbiological samples were plated to count the colony-forming units (CFU). Results. The 2% chlorhexidine gel and 2% chlorhexidine liquid significantly reduced the E faecalis CFU in the post-treatment and final microbiological samples. The 5.25% sodium hypochlorite also reduced the E faecalis CFU immediately after the root canal instrumentation, but it was not able to keep the root canal free of detectable E faecalis in the final sample. Conclusions. The 2% chlorhexidine gluconate (gel and liquid) antimicrobial ability was more effective than 5.25% sodium hypochlorite in keeping low CFU of E faecalis for 7 days after the biomechanical preparation.

Research paper thumbnail of Radiographic prevalence of root canal ramifications in a sample of root canal treatments in a Brazilian Dental School

Brazilian Oral Research, 2007

The aim of this study was to radiographically investigate the presence of root canal ramification... more The aim of this study was to radiographically investigate the presence of root canal ramifications found after endodontic treatment, and to determine any relationship between their presence and the type of the auxiliary chemical substance used. The study evaluated 1,470 endodontic treatments performed by final year undergraduate students at the Dental School of Piracicaba, State University of Campinas (UNICAMP), SP, Brazil, during the period from 1998 to 2000. The X-rays taken during treatment were evaluated in order to establish the presence of ramifications of the root canal system. The initial X-ray did not show the presence of any canal ramifications. After filling, X-rays showed only 3 ramification types: 3.06% of lateral canals, 2.99% of apical deltas, and 0.1% of interradicular canals. The maxillary premolars showed the highest number of lateral canals (n = 13), followed by mandibular premolars (n = 10) and maxillary incisors (n = 10). Apical deltas were mostly found in mandi...

Research paper thumbnail of Effect of Chemical Irrigants on the Bond Strength of a Self-Etching Adhesive to Pulp Chamber Dentin

Journal of Endodontics, 2006

The aim of this study was to evaluate the influence of endodontic irrigants on adhesion to pulp c... more The aim of this study was to evaluate the influence of endodontic irrigants on adhesion to pulp chamber dentin. Seventy crowns of bovine incisors were cut to expose the pulp chamber. Specimens were divided into seven groups, according to the irrigant solution used: G1, 0.9% sodium chlorite (control); G2, 5.25% NaOCl; G3, 5.25% NaOCl ϩ 17% EDTA; G4, 2% chlorhexidine solution; G5, 2% CHX solution ϩ 17% EDTA; G6, 2% chlorhexidine in a gel base; and G7, 2% CHX gel ϩ 17% EDTA. After irrigation, Clearfil SE Bond was applied to pulp chamber dentin, followed by Filtek Z250 composite. Six rectangular sticks were obtained from each specimen and dentin/resin interface was tested in tension. Bond strength means were analyzed by ANOVA and Tukey test. There was a significant decrease in bond strength associated to NaOCl, whereas chlorhexidine irrigation showed no effects on adhesion. It was concluded that endodontic irrigants affected differently bond strength to pulp chamber dentin.

Research paper thumbnail of Pulp Revascularization after Root Canal Decontamination with Calcium Hydroxide and 2% Chlorhexidine Gel

Journal of Endodontics, 2013

Introduction: Pulp revascularization may be considered a promising alternative for necrotic immat... more Introduction: Pulp revascularization may be considered a promising alternative for necrotic immature teeth. Many studies have accomplished passive decontamination associated with an antibiotic paste. To date, there is no report evaluating calcium hydroxide associated with 2% chlorhexidine gel for revascularization therapy. The aim of this case report was to describe a new proposal for pulp revascularization with mechanical decontamination and intracanal medication composed of calcium hydroxide and 2% chlorhexidine gel. Methods: The patient, a 9-year-old girl, suffered an intrusion associated with pulp exposure caused by an enamel-dentin fracture in her maxillary left central incisor. After diagnosis, treatment consisted of revascularization therapy with gentle manual instrumentation of the cervical and medium thirds of the root in addition to intracanal medication with calcium hydroxide and 2% chlorhexidine gel for 21 days. In the second session, a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate (MTA; Angelus, Londrina, Paran a, Brazil) was used for cervical sealing of the canal. Coronal sealing was performed with temporary filling material and composite resin. Results: During the follow-up period, the root canal space showed a progressive decrease in width, mineralized tissue deposition on root canal walls, and apical closure. A cone-beam computed tomography scan taken at the 2-year follow-up confirmed these findings and did not show complete root canal calcification. Conclusions: This new proposal for revascularization therapy with 2% chlorhexidine gel may be used for the treatment of necrotic immature root canals.

Research paper thumbnail of Enterococcus faecalis in dental root canals detected by culture and by polymerase chain reaction analysis

Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 2006

The objective of this study was to investigate the presence of Enterococcus faecalis in endodonti... more The objective of this study was to investigate the presence of Enterococcus faecalis in endodontic infections by culture and polymerase chain reaction analyses. Study design. Microbial samples were obtained from 50 teeth with untreated necrotic pulps (primary infection) and from 50 teeth with failing endodontic treatment (secondary infection). Culture techniques were used including serial dilution, plating, incubation, and biochemical identification. For PCR detection, samples were analyzed using a species-specific primer of the 16S rDNA and the downstream intergenic spacer region. Results. Culture and PCR detected the test species in 23 of 100 and 79 of 100 of the teeth, respectively. E faecalis was cultured from 2 (4%) of 50 necrotic canals and from 21 (42%) of 50 root-treated canals. PCR detection identified the target species in 41 (82%) and 38 (76%) of 50 primary and secondary infections respectively. Conclusion. E faecalis was detected as frequently in teeth with necrotic pulp as in teeth with failing endodontic treatment when a PCR analysis was used.

Research paper thumbnail of Root canal microbiota of dogs’ teeth with periapical lesions induced by two different methods

Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 2006

Objective. The microbial composition was investigated in root canals of dogs' teeth with periapic... more Objective. The microbial composition was investigated in root canals of dogs' teeth with periapical lesions induced by 2 different methods: open versus sealed canals. Study design. Teeth from Group I (n ϭ 16) were left open for a week, then sealed with composite resin for 120 days. The teeth from Group II (n ϭ 16) were left open for the same period. Microbiological samples from the root canals were collected and processed by the anaerobic technique for identification and counting of microorganisms after establishment of periapical reactions. Results. Seventy-four cultivable isolates were recovered in sealed canals (Group I). Strict anaerobes accounted for 64.9% of all species isolated, and gram-negative microorganisms accounted for 55.4%. Microbial genera most frequently isolated were Prevotella, Fusobacterium, Peptostreptococcus, Streptococcus, Enterococcus, Clostridium, and Porphyromonas. Statistical analysis by Pearson chi-square or Fisher's test revealed positive association between sealed teeth and strict anaerobes (P Ͻ .05). In open canals (Group II), from a total of 58 cultivable isolates, 19% were strict anaerobes and 81% facultative anaerobes, with predominance of gram-positive species (75.8%). Genera most frequently isolated were Streptococcus, Propionibacterium, Staphylococcus, Neisseria, and Prevotella. Conclusion. Strict anaerobes were most frequently found in sealed teeth rather than in the teeth with canals left exposed to the oral cavity for 4 months. Therefore, the method that induced periapical inflammatory lesions by intentional oral exposure, followed by tooth sealing, produced root canal microbiota similar to the same found in humans.

Research paper thumbnail of Recovery of Enterococcus faecalis after single‐ or multiple‐visit root canal treatments carried out in infected teeth ex vivo

International Endodontic Journal, 2005

Aim To assess the presence of Enterococcus faecalis after root canal treatment in single or mult... more Aim To assess the presence of Enterococcus faecalis after root canal treatment in single or multiple visits in an ex vivo model.Methodology Forty‐five premolar teeth were infected ex vivo with E. faecalis for 60 days. The canals were then prepared using a crowndown technique with System GT and Gates–Glidden burs and irrigated with 2% chlorhexidine gel. The specimens were divided into five groups (G1, G2, G3, G4 and G5) according to the time elapsed between chemical–mechanical preparation and root canal filling, the irrigant solution used and the use or nonuse of a calcium hydroxide intra‐canal medicament. The teeth were then root‐filled and incubated for 60 days at 37 °C. Dentine chips were removed from the canal walls with sequential sterile round burs at low speed. The samples obtained with each bur were immediately collected in separate test tubes containing Brain–Heart Infusion broth. These samples were placed onto agar plates and colony forming units were counted after 24 h a...

Research paper thumbnail of In vitro antimicrobial activity of sodium hypochlorite and chlorhexidine against selected single‐species biofilms

International Endodontic Journal, 2006

Aim To investigate the antimicrobial activity of 2.5% and 5.25% sodium hypochlorite and 2.0% chl... more Aim To investigate the antimicrobial activity of 2.5% and 5.25% sodium hypochlorite and 2.0% chlorhexidine gel and liquid as endodontic‐irrigating substances against selected single‐species biofilms.Methods Single‐species biofilms of Enterococcus faecalis, Staphylococcus aureus, Candida albicans, Prevotella intermedia, Porphyromonas gingivalis, Porphyromonas endodontalis and Fusobacterium nucleatum were generated on a cellulose nitrate membrane placed on agar medium. The biofilms were then immersed in the endodontic‐irrigating substances for 30 s and also for 5, 10, 15, 30 and 60 min, with and without mechanical agitation. Sterile saline was used as control. After each time period, the membrane filters were then transferred to tubes containing 2 mL of fresh broth medium plus neutralizers (in order to prevent the residual action of the tested substances). The micro‐organisms were suspended using a vortex, and the inoculum was serially diluted 10‐fold. Aliquots of the dilutions were...

Research paper thumbnail of In vitro antimicrobial activity of several concentrations of sodium hypochlorite and chlorhexidine gluconate in the elimination of Enterococcus faecalis

International Endodontic Journal, 2001

AimThe aim of this study was to assess, in vitro, the effectiveness of several concentrations of ... more AimThe aim of this study was to assess, in vitro, the effectiveness of several concentrations of NaOCl (0.5%, 1%, 2.5%, 4% and 5.25%) and two forms of chlorhexidine gluconate (gel and liquid) in three concentrations (0.2%, 1% and 2%) in the elimination of E. faecalis.MethodologyA broth dilution test using 24‐well cell culture plates was performed and the time taken for the irrigants to kill bacterial cells was recorded. Isolated 24 h colonies of pure cultures of E. faecalis grown on 10% sheep blood plus Brain Heart Infusion (BHI) agar plates were suspended in sterile 0.85% NaCl solution. The cell suspension was adjusted spectrophotometrically to match the turbidity of a McFarland 0.5 scale. One mL of each tested substance was placed on the bottom of wells of 24‐well cell culture plates (Corning, NY), including the control group (sterile saline). Six wells were used for each time period and irrigant concentration. Two mL of the bacterial suspension were ultrasonically mixed for 10 s ...

Research paper thumbnail of Avaliação da capacidade de remoção da smear layer das paredes de canais instrumentados utilizando diferentes substancias quimicas auxiliares ao preparo quimico-mecanico

INTRODUÇÃO 2 REVISÃO DA LITERATURA 2.1 Considerações sobre a Smear Layer 2.2 Substâncias Químicas... more INTRODUÇÃO 2 REVISÃO DA LITERATURA 2.1 Considerações sobre a Smear Layer 2.2 Substâncias Químicas Auxiliares à remoção da smear layer. 2.3 Clorexidina como substância química auxiliar ao preparo químicomecânico. 3 PROPOSIÇÃO 4 MATERIAL E MÉTODOS 4.1 Seleção e coleta da amostra 4.2 Preparo químico-mecânico dos canais radiculares 4.3 Procedimento de clivagem 4.4 Análise em Microscopia Eletrônica de Varredura 4.5 Análise estatística 5 RESULTADOS 5.1 Dados obtidos após análise dos espécimes no TERÇO CERVICAL. X 5.2 Dados obtidos após análise dos espécimes no TERÇO MÉDIO 5.3 Dados obtidos após análise dos espécimes no TERÇO APICAL 5.4 Dados obtidos após análise dos espécimes considerando os terços cervical, médio e apical.

Research paper thumbnail of Estudo in vitro da atividade antimicrobiana imediata e mediata da clorexidina gel 2% usada como irrigante endodontico contra Enterococcus faecalis

CJJedíco e.sfe frt1bt1/ho, 9los meus país Üebaslíiio e 9tlaría 9ielena, pelo exemplo de lula e co... more CJJedíco e.sfe frt1bt1/ho, 9los meus país Üebaslíiio e 9tlaría 9ielena, pelo exemplo de lula e conquísla de um ideal pelo amor, carinho, ensinamento, afelo e dedicação que ílumínamm meus caminhos obscuros; pela renúncia de seus sonhos pam que eu pudesse realizar os meus. 9los meus aoós, cpedro, 9lnlônía, Carolina e 9luguslo (in memorian), pelo exemplo de comgem, perseoemnça e dignidade para enfrentar as dificuldades que tl oida nos impõe. 9t 8uliana pelo tlmor, carinho, pacíênda e lodo apoio pam lular por nosso ideal Vil Vl11 c5e vencemos, 9llguém esteve conosco. c5e nada conseguimos, ele conlínua junto a nós. c5e persíslínnos juntos, veremos realmente que Quem nos foz conlínuar sorrirá para nós, mesmo que CJJele, na folícídade, nós tenhamos esquecido. IX 9lo meu orientador cprof CJJr. Caio Cezar CJ(andi Cferraz 9l você, que quando deveria .ser .simplesmente professor, foi meu We.sfre, Que quando deveria .ser .simplesmente mestre, foi meu :llmigo e em .sua amizade me compreendeu e me incenfívou a .seguir meu caminho.

Research paper thumbnail of Apexification with a New Intra-Canal Medicament: A Multidisciplinary Case Report

iranian endodontic journal, 2012

Dental trauma generally requires multidisciplinary planning and treatment for good prognosis. Whe... more Dental trauma generally requires multidisciplinary planning and treatment for good prognosis. When immature teeth are traumatized to a degree where pulp necrosis ensues, the objective of root canal treatment should be apexogenesis and root maturation. Apexification of the root is the conventional choice, which involves cleaning the canal and filling it with a temporary medication that stimulates the formation of a calcific apical barrier. Dental Trauma Service of Piracicaba Dental School, State University of Campinas (UNICAMP), Brazil employs a dressing for apexification treatments with calcium hydroxide, chlorhexidine gel 2% and zinc oxide. This paper reports the case of a dental trauma of the maxillary central incisors and subluxation on teeth 11, 12 and 21 that were treated with multidisciplinary collaboration (Endodontics, Periodontology and Operative Dentistry) to improve prognosis. After five-years there were no pathological conditions and the teeth showed every evidences of s...

Research paper thumbnail of Evaluation of Endodontic Treatments Performed by Students in a Brazilian Dental School

Journal of Dental Education, 2005

The aims of this study were to evaluate the clinical outcomes of root canal treatments performed ... more The aims of this study were to evaluate the clinical outcomes of root canal treatments performed by final‐year students in the Dental School of Piracicaba, State University of Campinas, SP, Brazil, during the year 2000 and to evaluate the success rate of these treatments at follow‐ups conducted one and three years later (2001–03). All 579 endodontic treatments performed by final‐year students were selected for this investigation. Detailed personal and dental history was obtained from the patient's records. Clinical and radiographic follow‐up examinations were performed. For 78.8 percent of the cases, dental caries was recorded as the cause for performing endodontic treatment; for 8.8 percent, prosthetic reasons were given; and for 12.4 percent, failure of the endodontic treatment was the reason. The largest percentage (30.7 percent) of recalled patients was examined after one year; the success rate at this follow‐up evaluation ranged from 83 percent to 96 percent depending on th...

Research paper thumbnail of Treponema diversity in root canals with endodontic failure

European Journal of Dentistry, 2013

ABSTRACTObjective: This study sought to investigate the prevalence of eight oral Treponemas (Trep... more ABSTRACTObjective: This study sought to investigate the prevalence of eight oral Treponemas (Treponema denticola, T. amylovorum, T. maltophilum, T. medium, T. pectinovorum, T. socranskii, T. vicentii and T. lecithinolyticum) in teeth with endodontic treatment failure and periapical lesion.Methods: Samples were taken from 40 root canals presenting endodontic failure and periapical lesion. DNA extraction was performed and Nested-PCR technique was used for the detection of Treponema species using specific primers.Results: Treponemas was detected in 56.5% of the samples analyzed (22/39). Individual root canals yielded a maximum of 6 target Treponema species. T. denticola (30.8%) and T. maltophilum (30.8%) were the most frequently detected species followed by T. medium (20.5%), T. socranskii (20.5%), T. pectinovorum (17.9%) and T. vicentii (17.9%). Positive association was verified between T. denticola and T. maltophilum such as T. medium (P<.05). T. lecithinolyticum was positively as...

Research paper thumbnail of In Vitro Assessment of the Antimicrobial Action and the Mechanical Ability of Chlorhexidine Gel as an Endodontic Irrigant

Journal of Endodontics, 2001

The objective of this study was to assess the chlorhexidine gluconate gel as an endodontic irriga... more The objective of this study was to assess the chlorhexidine gluconate gel as an endodontic irrigant. First the ability of chlorhexidine gel to disinfect root canals contaminated in vitro with Enterococcus faecalis was investigated. A scanning electron microscope was also used to evaluate its cleansing ability compared with endodontic irrigants commonly used, such as sodium hypochlorite and chlorhexidine gluconate liquid. The results indicated that the chlorhexidine gel produced a cleaner root canal surface and had an antimicrobial ability comparable with that obtained with the other solutions tested. It was concluded that chlorhexidine gluconate in gel form has potential for use as an endodontic irrigant.

Research paper thumbnail of Antimicrobial and cytotoxic effects of phosphoric acid solution compared to other root canal irrigants

Journal of Applied Oral Science, 2015

P hosphoric acid has been suggested as an irrigant due to its effectiveness in removing the smear... more P hosphoric acid has been suggested as an irrigant due to its effectiveness in removing the smear layer. Objectives: The purpose of this study was to compare the antimicrobial and cytotoxic effects of a 37% phosphoric acid solution to other irrigants commonly used in endodontics. Material and Methods: The substances 37% phosphoric acid, 17% EDTA, 10% citric acid, 2% chlorhexidine (solution and gel), and 5.25% NaOCl were evaluated. The antimicrobial activity was tested against Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Actinomyces meyeri, Parvimonas micra, Porphyromonas gingivalis, and Prevotella nigrescens according to the agar diffusion method. The cytotoxicity of the irrigants was determined by using the MTT assay. Results: Phosphoric acid presented higher antimicrobial activity compared to the other tested irrigants. With regard to the cell viability, this solution showed results similar to those with 5.25% NaOCl and 2% chlorhexidine (gel and solution), whereas 17% EDTA and 10% citric acid showed higher cell viability compared to other irrigants. Conclusion: Phosphoric acid demonstrated higher antimicrobial activity and cytotoxicity similar to that of 5.25% NaOCl and 2% chlorhexidine (gel and solution).

Research paper thumbnail of Monitoring the effectiveness of root canal procedures on endotoxin levels found in teeth with chronic apical periodontitis

Journal of Applied Oral Science, 2014

The aim of this study was to monitor the effectiveness of root canal procedures by using differen... more The aim of this study was to monitor the effectiveness of root canal procedures by using different irrigants and intracanal medication on endotoxin levels found in root canals of teeth with chronic apical periodontitis. Material and methods: Thirty root canals of teeth with pulpal necrosis associated with periapical lesions were selected and randomly divided into groups according to the irrigants used: GI-2.5% NaOCl, GII-2% chlorhexidine (CHX) gel, and GIII-saline solution (SS) (all, n=10). Samples were collected with sterile/apyrogenic paper points before (S1) and after root canal instrumentation (S2), after use of 17% ethylenediaminetetraacetic acid (EDTA) (S3), and after 30 days of intracanal medication (Ca(OH)2+SS) (S4). A turbidimetric kinetic Limulus Amebocyte Lysate assay was used for endotoxin measurement. Results: Endotoxins were detected in 100% of the root canals investigated (30/30), with a median value of 18.70 EU/mL. After irrigant tested: 2.5% NaOCl (99.65%) (GI), 2% CHX (94.27%) (GII), and SS (96.79%) (GIII) (all p<0.05). Root canal rinse with 17% EDTA (S3) for a 3-minute period failed to decrease endotoxin levels in GI and a slight decrease was observed in GII (59%) and GIII residual endotoxins: 2.5% NaOCl (90%) (GI), 2% CHX (88.8%) (GII), and SS (85.7%) (GIII, p<0.05). No differences were found in the endotoxin reduction when comparing enduring root canal instrumentation for the endotoxin removal from root canals of teeth with chronic apical periodontitis. Moreover, the use of intracanal medication for 30 days contributed for an improvement of endotoxin reduction.

Research paper thumbnail of Chlorhexidine gel associated with papain in pulp tissue dissolution

Restorative Dentistry & Endodontics, 2013

Chlorhexidine gel associated with papain in pulp tissue dissolution Objectives: This study aimed ... more Chlorhexidine gel associated with papain in pulp tissue dissolution Objectives: This study aimed to evaluate the capacity of 2% chlorhexidine gel associated with 8% papain gel in comparison with 5.25% sodium hypochlorite in bovine pulp tissue dissolution. Materials and Methods: Ninety bovine pulps of standardized sizes were used and fragmented into 5-mm sizes. The fragments were removed from the root middle third region. They were divided into 6 experimental groups (n = 15), 1) 8% papain; 2) 2% chlorhexidine; 3) 2% chlorhexidine associated with 8% papain; 4) 0.9% saline solution; 5) 2.5% sodium hypochlorite; and 6) 5.25% sodium hypochlorite. The pulp fragments were weighed and put into immobile test tubes for dissolution for time intervals of 30, 60, 90, and 120 min. Results: The 5.25% sodium hypochlorite had greater dissolution potential than the pure papain, and when associated with chlorhexidine, both promoted greater dissolution than did the saline solution and 2% chlorhexidine groups (p < 0.05). The 2.5% sodium hypochlorite promoted dissolution to a lesser extent than the groups with papain within a period of 30 min (p < 0.05), but, was comparable to the saline solution and chlorhexidine. After 120 min, the 2.5% and 5.25% sodium hypochlorite promoted dissolution of 100% of the pulp fragments, and papain, 61%, while chlorhexidine associated with papain and chlorhexidine alone dissolved only 55% and 3%, respectively. Conclusions: The 8% papain in gel, both alone and in association with chlorhexidine, was able to dissolve bovine pulp tissue, but to a lesser extent than did 5.25% sodium hypochlorite.

Research paper thumbnail of Efficacy of ethylene-diamine-tetra-acetic acid associated with chlorhexidine on intracanal medication removal: A scanning electron microscopy study

Microscopy Research and Technique, 2014

The aim of this study was to evaluate the effectiveness of 17% ethylene-diamine-tetra-acetic acid... more The aim of this study was to evaluate the effectiveness of 17% ethylene-diamine-tetra-acetic acid (EDTA) used alone or associated with 2% chlorhexidine gel (CHX) on intracanal medications (ICM) removal. Sixty single-rooted human teeth with fully formed apex were selected. The cervical and middle thirds of each canal were prepared with Gates Glidden drills and rotary files. The apical third was shaped with hand files. The specimens were randomly divided into two groups depending on the ICM used after instrumentation: calcium hydroxide Ca(OH)(2) +CHX or Ca(OH)(2) +sterile saline (SS). After seven days, each group was divided into subgroups according to the protocol used for ICM removal: instrumentation and irrigation either with EDTA, CHX+EDTA, or SS (control groups). All specimens were sectioned and processed for observation of the apical thirds by using scanning electron microscopy. Two calibrated evaluators attributed scores to each specimen. The differences between the protocols for ICM removal were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Friedman and Wilcoxon signed rank tests were used for comparison between the score of debris obtained in each root canal third. Remains of Ca(OH)(2) were found in all specimens independently of the protocol and ICM used (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 0.05). Seventeen percent EDTA showed the best results in removing ICM when used alone…

Research paper thumbnail of Comparison of Endotoxin Levels in Previous Studies on Primary Endodontic Infections

Journal of Endodontics, 2011

Background: This study was performed to determine which of the quantitative methods, namely, chro... more Background: This study was performed to determine which of the quantitative methods, namely, chromogenic endpoint, chromogenic kinetic, and turbidimetric kinetic ones, best fit for the analysis of primary endodontic infections. Methods: Twenty-one root canals with apical periodontitis were sampled with paper points. The same sample was analyzed by means of the endpoint chromogenic Limulus amebocyte lysate (LAL) assay (QCL), quantitative kinetic chromogenic LAL assay (KQCL), and kinetic turbidimetric LAL assay (Turbidimetric). Results: All three LAL methods were effective in the recovery of endotoxin from root canal infection. Regardless of the method tested, endotoxin was detected in 100% of the root canals (21/21). The KQCL assay yielded a median value of endotoxin of 7.49 EU/ mL, close to and not significantly different from those for the turbidimetric test (9.19 EU/mL) (both kinetic methods) (p > 0.05). In contrast, the endpoint QCL showed a median value of 34.20 EU/mL (p < 0.05). The comparison of the three methods revealed that both turbidimetric and KQCL methods were more precise, with best reproducibility (the coefficient variation between analysis of the root canal and its duplicate was lower than 10%). The inhibition/enhancement assay indicated a good interaction between the root canal samples with the turbidimetric method. Conclusion: This study has revealed that quantitative kineticturbidimetric and kinetic-chromogenic LAL methods are best fitted for the analysis of endotoxins in root canal infection, both being more precise and allowing better reproducibility compared with the endpoint-QCL assay.

Research paper thumbnail of In vitro assessment of the immediate and prolonged antimicrobial action of chlorhexidine gel as an endodontic irrigant against Enterococcus faecalis

Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 2005

The aim of this study was to assess in vitro the antimicrobial activity of 2% chlorhexidine gel a... more The aim of this study was to assess in vitro the antimicrobial activity of 2% chlorhexidine gel against Enterococcus faecalis, comparing it to other endodontic irrigants (2% chlorhexidine liquid and 5.25% sodium hypochlorite). Study design. Eighty roots of human mandibular premolars were prepared by serial instrumentation technique, autoclaved, and contaminated for 7 days with E faecalis monocultures. The roots were then divided into 5 groups according to the irrigant substance used during the standardized biomechanical preparation. In order to evaluate the antimicrobial action of the irrigant substances, 3 microbial samples were taken: initial (before the biomechanical preparation); post-treatment (immediately after the biomechanical preparation), and final (7 days after the biomechanical preparation). The microbiological samples were plated to count the colony-forming units (CFU). Results. The 2% chlorhexidine gel and 2% chlorhexidine liquid significantly reduced the E faecalis CFU in the post-treatment and final microbiological samples. The 5.25% sodium hypochlorite also reduced the E faecalis CFU immediately after the root canal instrumentation, but it was not able to keep the root canal free of detectable E faecalis in the final sample. Conclusions. The 2% chlorhexidine gluconate (gel and liquid) antimicrobial ability was more effective than 5.25% sodium hypochlorite in keeping low CFU of E faecalis for 7 days after the biomechanical preparation.

Research paper thumbnail of Radiographic prevalence of root canal ramifications in a sample of root canal treatments in a Brazilian Dental School

Brazilian Oral Research, 2007

The aim of this study was to radiographically investigate the presence of root canal ramification... more The aim of this study was to radiographically investigate the presence of root canal ramifications found after endodontic treatment, and to determine any relationship between their presence and the type of the auxiliary chemical substance used. The study evaluated 1,470 endodontic treatments performed by final year undergraduate students at the Dental School of Piracicaba, State University of Campinas (UNICAMP), SP, Brazil, during the period from 1998 to 2000. The X-rays taken during treatment were evaluated in order to establish the presence of ramifications of the root canal system. The initial X-ray did not show the presence of any canal ramifications. After filling, X-rays showed only 3 ramification types: 3.06% of lateral canals, 2.99% of apical deltas, and 0.1% of interradicular canals. The maxillary premolars showed the highest number of lateral canals (n = 13), followed by mandibular premolars (n = 10) and maxillary incisors (n = 10). Apical deltas were mostly found in mandi...

Research paper thumbnail of Effect of Chemical Irrigants on the Bond Strength of a Self-Etching Adhesive to Pulp Chamber Dentin

Journal of Endodontics, 2006

The aim of this study was to evaluate the influence of endodontic irrigants on adhesion to pulp c... more The aim of this study was to evaluate the influence of endodontic irrigants on adhesion to pulp chamber dentin. Seventy crowns of bovine incisors were cut to expose the pulp chamber. Specimens were divided into seven groups, according to the irrigant solution used: G1, 0.9% sodium chlorite (control); G2, 5.25% NaOCl; G3, 5.25% NaOCl ϩ 17% EDTA; G4, 2% chlorhexidine solution; G5, 2% CHX solution ϩ 17% EDTA; G6, 2% chlorhexidine in a gel base; and G7, 2% CHX gel ϩ 17% EDTA. After irrigation, Clearfil SE Bond was applied to pulp chamber dentin, followed by Filtek Z250 composite. Six rectangular sticks were obtained from each specimen and dentin/resin interface was tested in tension. Bond strength means were analyzed by ANOVA and Tukey test. There was a significant decrease in bond strength associated to NaOCl, whereas chlorhexidine irrigation showed no effects on adhesion. It was concluded that endodontic irrigants affected differently bond strength to pulp chamber dentin.

Research paper thumbnail of Pulp Revascularization after Root Canal Decontamination with Calcium Hydroxide and 2% Chlorhexidine Gel

Journal of Endodontics, 2013

Introduction: Pulp revascularization may be considered a promising alternative for necrotic immat... more Introduction: Pulp revascularization may be considered a promising alternative for necrotic immature teeth. Many studies have accomplished passive decontamination associated with an antibiotic paste. To date, there is no report evaluating calcium hydroxide associated with 2% chlorhexidine gel for revascularization therapy. The aim of this case report was to describe a new proposal for pulp revascularization with mechanical decontamination and intracanal medication composed of calcium hydroxide and 2% chlorhexidine gel. Methods: The patient, a 9-year-old girl, suffered an intrusion associated with pulp exposure caused by an enamel-dentin fracture in her maxillary left central incisor. After diagnosis, treatment consisted of revascularization therapy with gentle manual instrumentation of the cervical and medium thirds of the root in addition to intracanal medication with calcium hydroxide and 2% chlorhexidine gel for 21 days. In the second session, a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate (MTA; Angelus, Londrina, Paran a, Brazil) was used for cervical sealing of the canal. Coronal sealing was performed with temporary filling material and composite resin. Results: During the follow-up period, the root canal space showed a progressive decrease in width, mineralized tissue deposition on root canal walls, and apical closure. A cone-beam computed tomography scan taken at the 2-year follow-up confirmed these findings and did not show complete root canal calcification. Conclusions: This new proposal for revascularization therapy with 2% chlorhexidine gel may be used for the treatment of necrotic immature root canals.

Research paper thumbnail of Enterococcus faecalis in dental root canals detected by culture and by polymerase chain reaction analysis

Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 2006

The objective of this study was to investigate the presence of Enterococcus faecalis in endodonti... more The objective of this study was to investigate the presence of Enterococcus faecalis in endodontic infections by culture and polymerase chain reaction analyses. Study design. Microbial samples were obtained from 50 teeth with untreated necrotic pulps (primary infection) and from 50 teeth with failing endodontic treatment (secondary infection). Culture techniques were used including serial dilution, plating, incubation, and biochemical identification. For PCR detection, samples were analyzed using a species-specific primer of the 16S rDNA and the downstream intergenic spacer region. Results. Culture and PCR detected the test species in 23 of 100 and 79 of 100 of the teeth, respectively. E faecalis was cultured from 2 (4%) of 50 necrotic canals and from 21 (42%) of 50 root-treated canals. PCR detection identified the target species in 41 (82%) and 38 (76%) of 50 primary and secondary infections respectively. Conclusion. E faecalis was detected as frequently in teeth with necrotic pulp as in teeth with failing endodontic treatment when a PCR analysis was used.

Research paper thumbnail of Root canal microbiota of dogs’ teeth with periapical lesions induced by two different methods

Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 2006

Objective. The microbial composition was investigated in root canals of dogs' teeth with periapic... more Objective. The microbial composition was investigated in root canals of dogs' teeth with periapical lesions induced by 2 different methods: open versus sealed canals. Study design. Teeth from Group I (n ϭ 16) were left open for a week, then sealed with composite resin for 120 days. The teeth from Group II (n ϭ 16) were left open for the same period. Microbiological samples from the root canals were collected and processed by the anaerobic technique for identification and counting of microorganisms after establishment of periapical reactions. Results. Seventy-four cultivable isolates were recovered in sealed canals (Group I). Strict anaerobes accounted for 64.9% of all species isolated, and gram-negative microorganisms accounted for 55.4%. Microbial genera most frequently isolated were Prevotella, Fusobacterium, Peptostreptococcus, Streptococcus, Enterococcus, Clostridium, and Porphyromonas. Statistical analysis by Pearson chi-square or Fisher's test revealed positive association between sealed teeth and strict anaerobes (P Ͻ .05). In open canals (Group II), from a total of 58 cultivable isolates, 19% were strict anaerobes and 81% facultative anaerobes, with predominance of gram-positive species (75.8%). Genera most frequently isolated were Streptococcus, Propionibacterium, Staphylococcus, Neisseria, and Prevotella. Conclusion. Strict anaerobes were most frequently found in sealed teeth rather than in the teeth with canals left exposed to the oral cavity for 4 months. Therefore, the method that induced periapical inflammatory lesions by intentional oral exposure, followed by tooth sealing, produced root canal microbiota similar to the same found in humans.

Research paper thumbnail of Recovery of Enterococcus faecalis after single‐ or multiple‐visit root canal treatments carried out in infected teeth ex vivo

International Endodontic Journal, 2005

Aim To assess the presence of Enterococcus faecalis after root canal treatment in single or mult... more Aim To assess the presence of Enterococcus faecalis after root canal treatment in single or multiple visits in an ex vivo model.Methodology Forty‐five premolar teeth were infected ex vivo with E. faecalis for 60 days. The canals were then prepared using a crowndown technique with System GT and Gates–Glidden burs and irrigated with 2% chlorhexidine gel. The specimens were divided into five groups (G1, G2, G3, G4 and G5) according to the time elapsed between chemical–mechanical preparation and root canal filling, the irrigant solution used and the use or nonuse of a calcium hydroxide intra‐canal medicament. The teeth were then root‐filled and incubated for 60 days at 37 °C. Dentine chips were removed from the canal walls with sequential sterile round burs at low speed. The samples obtained with each bur were immediately collected in separate test tubes containing Brain–Heart Infusion broth. These samples were placed onto agar plates and colony forming units were counted after 24 h a...

Research paper thumbnail of In vitro antimicrobial activity of sodium hypochlorite and chlorhexidine against selected single‐species biofilms

International Endodontic Journal, 2006

Aim To investigate the antimicrobial activity of 2.5% and 5.25% sodium hypochlorite and 2.0% chl... more Aim To investigate the antimicrobial activity of 2.5% and 5.25% sodium hypochlorite and 2.0% chlorhexidine gel and liquid as endodontic‐irrigating substances against selected single‐species biofilms.Methods Single‐species biofilms of Enterococcus faecalis, Staphylococcus aureus, Candida albicans, Prevotella intermedia, Porphyromonas gingivalis, Porphyromonas endodontalis and Fusobacterium nucleatum were generated on a cellulose nitrate membrane placed on agar medium. The biofilms were then immersed in the endodontic‐irrigating substances for 30 s and also for 5, 10, 15, 30 and 60 min, with and without mechanical agitation. Sterile saline was used as control. After each time period, the membrane filters were then transferred to tubes containing 2 mL of fresh broth medium plus neutralizers (in order to prevent the residual action of the tested substances). The micro‐organisms were suspended using a vortex, and the inoculum was serially diluted 10‐fold. Aliquots of the dilutions were...

Research paper thumbnail of In vitro antimicrobial activity of several concentrations of sodium hypochlorite and chlorhexidine gluconate in the elimination of Enterococcus faecalis

International Endodontic Journal, 2001

AimThe aim of this study was to assess, in vitro, the effectiveness of several concentrations of ... more AimThe aim of this study was to assess, in vitro, the effectiveness of several concentrations of NaOCl (0.5%, 1%, 2.5%, 4% and 5.25%) and two forms of chlorhexidine gluconate (gel and liquid) in three concentrations (0.2%, 1% and 2%) in the elimination of E. faecalis.MethodologyA broth dilution test using 24‐well cell culture plates was performed and the time taken for the irrigants to kill bacterial cells was recorded. Isolated 24 h colonies of pure cultures of E. faecalis grown on 10% sheep blood plus Brain Heart Infusion (BHI) agar plates were suspended in sterile 0.85% NaCl solution. The cell suspension was adjusted spectrophotometrically to match the turbidity of a McFarland 0.5 scale. One mL of each tested substance was placed on the bottom of wells of 24‐well cell culture plates (Corning, NY), including the control group (sterile saline). Six wells were used for each time period and irrigant concentration. Two mL of the bacterial suspension were ultrasonically mixed for 10 s ...