Potential of curcumin-mediated photodynamic inactivation to reduce oral colonization.

OBJECTIVE: The present study assessed the susceptibility of salivary pathogens to photodynamic inactivation (PDI), mediated by a water-soluble mixture of curcuminoids (CRM) and LED light. METHODS: A 10mL sample of unstimulated saliva was collected from volunteers. The inoculum was prepared using 9mL of saline and 1mL of saliva. Inoculum suspensions were divided into 14 groups and treated according to the description below. Groups that received the PDI treatment (light for 1min or 5min and 1.5g/L or 3.0g/L of CRM concentration) were called C1.5L1.8, C1.5L9.0, C3.0L1.8, C3.0L9.0. To evaluate the CRM decontamination alone, the C1.5/1,C1.5/5,C3.0/1 and C3.0/5 groups were assessed. Likewise, light alone was evaluated through the L1.8 and L9.0 groups. Chlorhexidine at 0.12% (CLX) for 1 or 5min was used for the positive control groups (CLX1 and CLX5, respectively); saline was used for 1 or 5min (CTR1, CTR5, respectively) for the negative control groups. After the tests, serial dilutions were performed, and the resulting samples were plated on blood agar in microaerophilic conditions. The number of colony forming units (CFU/mL) was determined and log10-transformed. Data were analyzed using a One-way Analysis of Variance with Welch correction, followed by the Games Howell's test (α=0.05). Log reduction (LR) measure for antimicrobial efficacy was also calculated using data from the CTR5 as untreated samples. RESULTS: The CHX5 showed the best antimicrobial result, followed by the CLX1. The antimicrobial effect of CRM was more pronounced when associated with light (PDI), but significantly lower than the CLX5 effect. The C3.0L9.0 protocol showed similar results to the CLX1. CONCLUSION: The results show that PDI with CRM at the studied concentrations is as effective for oral decontamination in clinical dental care conditions as the CLX at 0.12% for 1min.

Use of computerized tomography for diagnosis and follow-up after endodontic surgery: clinical case report with 8 years of follow-up.

Computerized tomography (CT) is a valuable tool for diagnosis and planning in conventional and surgical endodontic therapy. This case report describes the use of CT in the diagnosis of a periapical lesion undetected by periapical radiography in the mandibular molar area. The CT also showed a possible mesial root perforation associated with the lesion. Following CT, surgical planning, periradicular curettage, and sealing of the root perforation were performed. Eight years after surgery, cone beam CT revealed periapical bone repair. Computerized tomography can be an important resource for diagnosis and planning in conventional and surgical endodontic therapy, as well as for evaluation of post-treatment bone repair.

Actividad antimicrobiana de diferentes tipos de cementos endodónticos

El objetivo de este estudio fue evaluar la actividad antimicrobiana de los cementos endodónticos a base de resina (Epiphany, Sealer 26 e AH Plus), cementos a base de silicona (Roeko Seal) y cementos de óxido de zinc y eugenol (Intrafill), sobre cinco diferentes especies de microorganismos. El método utilizado fue el de difusión en Agar. Una capa base fue confeccionada usando Agar Müller-Hinton (MH) y los pozos fueron formados por la remoción del Agar. Los materiales fueron colocados en los pozos después de su manipulación. Los microorganismos usados fueron: Micrococcus luteus (ATCC 9341), Staphylococcus aureus (ATCC6538), Escherichia coli (ATCC10538), Pseudomonas aeruginosa (ATCC27853), Candida albicans (ATCC 1023) y Enterococcus faecalis (ATCC 10541). Las placas fueron mantenidas a temperatura ambiente por 2 horas para pre-difusión y posteriormente incubadas a 37(0) C por 24 horas. Los resultados demostraron que el cemento Epiphany y el Sealer 26 presentaron actividad antimicrobiana sobre todas las cepas evaluadas. El cemento AH Plus y el Intrafill mostraron una acción antimicrobiana sobre todos los microorganismos excepto P aeruginosa y el Roeko Seal no fue efectivo sobre ningún microorganismo.

The aim of this study was to evaluate the antimicrobial activity of root canal sealers based on resins (Epiphany, Sealer 26 and AH Plus), silicon (Roeko Seal) and zinc oxide and eugenol (Intrafill), against five different microorganism strains. The agar diffusion method was used. A base layer was made using Müller-Hinton agar (MH) and wells were formed by removing agar. The materials were placed into the wells immediately after manipulation. The microorganisms used were: Micrococcus luteus (ATCC9341), Staphylococcus aureus (ATCC6538), Escherichia coli (ATCC10538), Pseudomonas aeruginosa (ATCC27853), Candida albicans (ATCC 10231), and Enterococcus faecalis (ATCC 10541).The plates were kept at room temperature for 2 h for prediffusion and then incubated at 37(0) C for 24 h. The results showed that Epiphany and Sealer 26 presented antimicrobial activity against all strains. AH Plus and Intrafill presented antimicrobial activity against all strains except P aeruginosa and Roeko Seal wasn’t effective against any microorganism.

Detection of periapical lesion development by conventional radiography or computed tomography.

OBJECTIVE: The aim of this study was to detect the development of experimentally induced periapical lesions using conventional radiography and computed tomography. STUDY DESIGN: The root canals of dogs' teeth were exposed to the oral environment for 7 days for contamination and then sealed for 7 days (GI), 15 days (GII), 30 days (GIII), and 60 days (GIV). Immediately after each experimental period, radiographs and tomograms were taken in order to detect the occurrence of periapical bone resorption. The periapical radiographs were digitized and areas of bone resorption were measured using the VIXWIN 2000 software. Scores were assigned to the tomograms based on the progression of periapical bone resorption. The specimens were evaluated by calibrated examiners who were blinded to the groups. The radiographic results were analyzed by ANOVA and Tukey's test (P < .05) and the tomographic results were analyzed by Kruskal-Wallis and Dunn's tests (P < .05). RESULTS: The radiographic evaluation did not reveal periapical lesions at the 7-day control. Lesions were radiographically visible at 15 and 30 days (47.4% and 77.8% of the cases, respectively) and presented similar dimensions (P > .05). At 60 days, lesions were detected in all specimens, presenting larger dimensions than those of the earlier evaluation periods (P < .05). The tomographic evaluation detected lesions at 7 and 15 days (32.5% and 83.3% of the cases, respectively). Lesions were detected in all specimens at the 30- and 60-day periods, when the greatest values of bone resorption were observed (P < .05). CONCLUSIONS: Tomography was able to detect periapical lesion development in its initial stages, even when the lesions were undetectable radiographically.

Antimicrobial activity of endodontic sealers based on calcium hydroxide and MTA.

The aim of this study was to evaluate the antimicrobial activity of a new root canal sealer containing calcium hydroxide (Acroseal) and the root canal sealer based on MTA (Endo CPM Sealer), in comparison with traditional sealers (Sealapex, Sealer 26 and Intrafill) and white MTA-Angelus, against five different microorganism strains. The materials and their components were evaluated after manipulation, employing the agar diffusion method. A base layer was made using Müller-Hinton agar (MH) and wells were made by removing agar. The materials were placed into the wells immediately after manipulation. The microorganisms used were: Micrococcus luteus (ATCC9341), Staphylococcus aureus (ATCC6538), Pseudomonas aeruginosa (ATCC27853), Candida albicans (ATCC 10231), and Enterococcus faecalis (ATCC 10541). The plates were kept at room temperature for 2 h for prediffusion and then incubated at 37 degrees C for 24 h. The results showed that Sealapex and its base paste, Sealer 26 and its powder, Endo CPM Sealer and its powder, white MTA and its powder all presented antimicrobial activity against all strains. Intrafill and its liquid presented antimicrobial activity against all strains except P. aeruginosa and Acroseal was effective only against M. luteus and S. aureus.

In vitro antimicrobial activity of endodontic sealers, MTA-based cements and Portland cement.

The aim of this study was to evaluate the antimicrobial activity of different root-end filling materials - Sealer 26, Sealapex with zinc oxide, zinc oxide and eugenol, white and gray Portland cement, white and gray MTA-Angelus, and gray Pro Root MTA - against six different microorganism strains. The agar diffusion method was used. A base layer was made using Müller-Hinton agar (MH) and wells were formed by removing the agar. The materials were placed in the wells immediately after manipulation. The microorganisms used were: Micrococcus luteus (ATCC9341), Staphylococcus aureus (ATCC6538), Escherichia coli (ATCC10538), Pseudomonas aeruginosa (ATCC27853), Candida albicans (ATCC 10231), and Enterococcus faecalis (ATCC 10541). The plates were kept at room temperature for 2 h for prediffusion and then incubated at 37 degrees C for 24 h. Triphenyltetrazolium chloride 0.05% gel was added for optimization, and the zones of inhibition were measured. Data were subjected to the Kruskal-Wallis and Dunn tests at a 5% significance level. The results showed that all materials had antimicrobial activity against all the tested strains. Analysis of the efficacy of the materials against the microbial strains showed that Sealapex with zinc oxide, zinc oxide and eugenol and Sealer 26 created larger inhibition halos than the MTA-based and Portland cements (P < 0.05). On the basis of the methodology used, it may be concluded that all endodontic sealers, MTA-based and Portland cements evaluated in this study possess antimicrobial activity, particularly the endodontic sealers.

Evaluation of periapical repair following retrograde filling with different root-end filling materials in dog teeth with periapical lesions.

OBJECTIVE: The objective of this study was to evaluate periapical repair following retrograde filling using different root-end filling materials. STUDY DESIGN: After induction of periapical lesions, 48 root canals from dog teeth were partially filled. Endodontic surgery was performed and 3 different materials were used for root-end filling: Sealer 26, Sealapex plus zinc oxide, or mineral trioxide aggregate (MTA). No additional procedures were performed in the control group after partial filling of the root canal. After 180 days, the animals were killed, the maxillas and mandibles were removed, and specimens were submitted for histologic processing. RESULTS: Histopathologic analysis revealed similar periapical repair for the groups in which Sealer 26, Sealapex plus zinc oxide, and MTA were used (P > .05). The control group showed unsatisfactory periapical repair (P < .05). CONCLUSION: There was no difference in periapical tissue healing after retrograde filling with the tested materials, which indicates that these 3 root-end filling materials are equally useful.

Comparison of rotary and manual instrumentation techniques on cleaning capacity and instrumentation time in deciduous molars.

PURPOSE: The aim of this study was to evaluate, in vitro, the cleaning capacity and time needed for instrumentation of root canals of deciduous molars by manual and rotary instrumentation. METHODS: Thirty-three deciduous molar root canals were injected with India ink and divided into 3 groups: group I--the root canal instrumented manually with K files; group II--the root canal instrumented with rotary Profile .04 instruments; group III--control group, (ie, root canals not instrumented). Instrumentation time was recorded. The teeth were cleared and the removal of India ink was measured in the cervical, middle, and apical thirds. RESULTS: There was no significant difference for cleaning capacity between manual and rotary techniques in the 3 root thirds (P>.05), but both techniques were different from the control group (P<.001). Significantly less time was needed for instrumentation with the rotary technique (3.46 minutes) than with the manual technique (9.06 minutes). CONCLUSIONS: Although no differences were found for cleaning capacity, the reduction of instrumentation time by the rotary technique was a relevant clinical factor for endodontic treatment.