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Aim: The aim of this study was to determine the bond strength (BS) of a self-adhesive resin cement to the contaminated root dentin., Materials and Methods: The crown and apical third of twenty single-rooted teeth were removed. The root canals were flared and 1-mm-thick root sections were obtained. The sections were rinsed, dried, and sterilized. The control group (n=20) was composed of one section of each third, which remained immersed in sterile trypticase soy broth (TSB) for 2 months. The other sections comprised the experimental group ( n = 40) and were immersed in a suspension of Enterococcus faecalis . The culture medium was changed at every 4 days for 2 months. The sections were rinsed with distilled water, dried, and the root canal space was filled with the self-adhesive resin cement RelyX™ U200. After 24 h, the push-out test was performed and the types of interface failure were observed on a stereo microscope., Statistical Analysis: Data were statistically analyzed by the nonparametric Mann-Whitney test (α=5%)., Results: A significant reduction was observed in the BS of resin cement to the contaminated dentin compared to the healthy dentin, for both thirds analyzed ( P < 0.05). The BS was significantly greater at the cervical third compared to the middle third for specimens in the experimental group ( P < 0.05). Adhesive and mixed failures were observed more frequently in specimens contaminated with E. faecalis., Conclusion: Bacterial contamination negatively infl uenced the BS of the self-adhesive resin cement to the root dentin, and there was a predominance of adhesive and mixed failures., Competing Interests: There are no conflicts of interest.

Background/aim: Natural resources, such as coconut water, propolis, and egg whites, have been examined as possible storage media for avulsed teeth. However, there is a lack of research focused on the efficacy of these three products together compared with Hank's balanced salt solution and milk. The aim of this study was to evaluate the capacity of seven storage media to maintain the viability of human periodontal ligament fibroblasts (PDLFs)., Material and Methods: PDLFs were kept at 5°C and 20°C, in skimmed milk (SMilk), whole milk (WMilk), recently prepared Hank's balanced salt solution (HBSS), Save-A-Tooth ® system's HBSS (Save), natural coconut water (Coconut), Propolis, and egg white (Egg) for 3, 6, 24, 48, 72, 96, and 120 h, through the analysis of tetrazolium salt-based colorimetric (MTT) assay., Results: At 5°C, SMilk and WMilk were better than HBSS in maintaining cell viability, from 24 h onward. At 20°C, HBSS was the best storage medium at 96 and 120 h. At both temperatures, from 6 h onward, Coconut, Propolis and Egg were less effective than SMilk, WMilk, and HBSS. In general, the performance of Coconut, Propolis and Egg were not influenced by storage temperature. However, the lowest temperature undermined the effectiveness of HBSS from 24 h and favored SMilk and WMilk, from 96 and 48 h onward, respectively. Save and water were the worst storage media., Conclusion: SMilk was the best storage medium, followed by WMilk and HBSS. Coconut, Propolis, and Egg can be indicated for the conservation of PDLF up to 3 h. The lower temperature (5°C) undermined the effectiveness of HBSS and favored SMilk and WMilk., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: To assess tooth crown's color after intracanal treatment with triple antibiotic paste (TAP) or calcium hydroxide (CH); cervical sealing with glass ionomer cement (GIC) or mineral trioxide aggregate (MTA); and bleaching with carbamide peroxide., Material and Methods: After pulp removal and color spectrophotometer measurement, 50 bovine incisors were divided into 4 experimental groups and one control (untreated). Experiments were performed in phases (Ph). Ph1: TAP (ciprofloxacin, metronidazole, minocycline), TAPM (ciprofloxacin, metronidazole, amoxicillin), DAP (ciprofloxacin, metronidazole), or CH treatment groups. After 1 and 3 days (d); 1, 2, 3 weeks (w); and 1, 2, 3 and 4 months (m), color was measured and medications were removed. Ph2: GIC or MTA cervical sealing, each using half of the specimens from each group. Color was assessed after 1d, 3d; 1w, 2w, 3w; 1m and 2m. Ph3: Two bleaching sessions, each followed by color measurement. Data were analyzed with ANOVA and post-hoc Holm-Sidak method., Results: Ph1: Specimens of TAP group presented higher color alteration (ΔE) mean than those of TAPM group. No significant difference was found among TAP or TAPM and CH, DAP or Control groups. Ph2: cervical sealing materials showed no influence on color alteration. Ph3: Different ΔE means (from different groups), prior to bleaching, became equivalent after one bleaching session., Conclusions: TAP induces higher color alteration than TAPM; color alteration increases over time; cervical sealing material has no influence on color alteration; and, dental bleaching was able to recover, at least partially, the tooth crown's color.

Aim: To evaluate nanoparticulate calcium carbonate (NPCC) using transmission electron microscopy and the effects of NPCC addition to MTA in regard to the setting time, dimensional change, compressive strength, solubility and pH., Methodology: The experimental groups were G1 (MTA), G2 (MTA with 5% NPCC) and G3 (MTA with 10% NPCC). The tests followed ISO and ADA standards. The specimens in the dimensional change and compressive strength tests were measured immediately after setting, after 24 h and after 30 days. In the solubility test, rings filled with cement were weighed after setting and after 30 days. The pH was measured after 24 h and 30 days. The data were analysed with the ANOVA, Tukey's and Kruskal-Wallis tests (α = 5%)., Results: The setting time was reduced (P < 0.05) in samples from G2 and G3 compared to G1. After 24 h, the dimensional change was similar amongst the groups, and after 30 days, G2 was associated with less alteration than G1 and G3. There was a difference in the compressive strength (P < 0.001) after 24 h and 30 days (G1 > G2 > G3). The solubility test revealed a difference amongst the groups when the specimens were hydrated: G2 > G1 > G3 and dehydrated: G3 > G2 > G1. The pH of the groups was similar at 24 h with higher values in each group after 30 days (P < 0.05), and G2 and G3 had similar mean pH values but both were higher than G1., Conclusions: Nanoparticulate calcium carbonate had a cubic morphology with few impurities. The addition of nanoparticulate calcium carbonate to MTA accelerated the setting time, decreased compressive strength and, after 30 days, resulted in lower dimensional change (G2), higher solubility and a higher pH., (© 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.)

Revascularization of immature teeth with necrotic pulps traditionally involves the use of triple antibiotic paste, which may sometimes lead to undesirable complications. The objective of this study was to assess tissue repair in immature dog teeth with apical periodontitis subjected to revascularization, comparing two different pastes used for root canal disinfection. Apical periodontitis was induced in 30 dog premolars. Teeth were randomly divided into three experimental groups: root canals filled with triple antibiotic paste (n = 10); root canals filled with 1% propolis paste (n = 10); and no medication (n = 10). An additional group (n = 10, no intervention) was used as control. After 7 months, the jaws were histologically evaluated for the following variables: newly formed mineralized tissue (present/absent); vital tissue in the canal space (absent/periodontal ligament-like/pulp-like); apical extension of root (present/absent); and severity of inflammatory process (absent/mild/moderate/severe). There were no statistically significant differences among the experimental groups in new mineralized tissue formation and apical root development. The formation of vital tissue in the canal space, in turn, was statistically different between the triple paste and propolis groups: vital tissues were present in all revascularized teeth disinfected with propolis paste (100%), compared to 71% of those disinfected with the triple paste. Severity of inflammatory process was different between the triple paste and no medication groups. The new tissues formed onto canal walls and in the root canal space showed characteristics of cementum and periodontal ligament, respectively. Propolis may have some advantages over the triple paste for the revascularization of immature teeth.

The objective of this study was to evaluate the effectiveness of various storage media at 20 °C in maintaining the viability of human periodontal ligament fibroblasts (HPLF) over time. HPLF were maintained at 20 °C in skim milk (SM), whole milk (WM), freshly prepared Hank's balanced salt solution (HBSS), Save-A-Tooth(r), natural coconut water (NCW), coconut water industrialized (ICW) and tap water (negative control) for 3, 6, 24, 48, 72, 96 and 120 h. Cells maintained in Minimal Essential Medium (MEM-37) at 37 °C served as a positive control. Cell viability was determined by MTT assay. Statistical analysis was performed by Kruskal-Wallis test and Scheffe test (α = 5%). From 24 h, NCW was significantly better in maintaining cell viability than all other tested storage media (p<0.05). SM and WM were significantly better than HBSS for up to 72 h. Save-A-Tooth(r) and ICW were the worst conservation storage media. In conclusion, the effectiveness of the tested storage media to maintain the viability of the periodontal ligament cells was as follows, in a descending order: NCW > MEM-37> SM and IM> HBSS> ICW > Save-A-Tooth(r)> tap water.

Objective: This study investigated the effect of passive ultrasonic irrigation (PUI) on diffusion of hydroxyl ions through radicular dentine., Materials and Methods: After chemomechanical preparation of root canals in 60 human teeth, the cementoenamel junction and the apical 3 mm of each root were covered with fast-setting adhesive. Four final irrigation protocols were applied (n = 10): group (G)1: irrigation with EDTA + NaOCl; G2: EDTA + PUI + NaOCl; G3: EDTA+(NaOCl + PUI); G4: (EDTA + PUI) + (NaOCl + PUI). Ten teeth irrigated with distilled water followed by PUI (G5) served as the negative control. After drying, the canals were filled with calcium hydroxide paste (CH), sealed and kept in individual vials containing 10 mL of distilled water with known pH values. At 7, 14, and 21 days, the pH of the water in the vials was measured. The pH values in various groups were analyzed with two-way ANOVA (irrigation protocol and time period as factors) and Holm-Sidak multiple comparison test (α = 0.05)., Results: Changes in pH was not significantly different among groups (P = 0.651) but was significant different among different time periods (P < 0.0001). For all groups, ion diffusion was higher at 14 and 21 days than at 7 days., Conclusions: PUI has no effect on diffusion of hydroxyl ions through radicular dentine. When CH is used as temporary filling material, a waiting period of at least 14 days is required to create an alkaline environment within the radicular dentine., Clinical Relevance: The use of PUI during final irrigation phase does not improve the action of CH when it is used as temporary filling material.

Florid cemento-osseous dysplasia (FCOD) belongs to the group of fibro-osseous lesions in which normal bone is replaced by fibrous connective tissue and calcified cementum tissue of the avascular type. Among the various types of fibro-osseous lesions, FCOD is one of the most commonly encountered diseases in clinical practice and may involve 3 or 4 of the quadrants. FCOD is located in the periapical regions of teeth, and the lesions are predominantly radiolucent (osteolytic phase), become mixed over time (cementoblast phase), and ultimately become radiopaque (osteogenic phase) with a thin radiolucent peripheral halo. The characteristics of FCOD in the initial stages are similar to those of periapical lesions of inflammatory origin, which may lead to misdiagnosis. A 38-year-old woman sought dental care because of complaints of pain on the right side of her face. A clinical examination revealed no marked alterations; a panoramic radiograph was therefore requested and revealed the presence of radiolucent lesions associated with the periapical regions of some of the lower teeth. Thus, the professional referred the patient for endodontic treatment of the associated teeth with the justification that the lesions were of endodontic origin. However, the endodontist found that the teeth responded positively to a sensitivity test. The initial diagnosis could have resulted in unnecessary root canal treatment, but after careful clinical, radiographic, and tomographic assessments by different professionals, FCOD was diagnosed, conservatively treated, and regularly monitored. It is important that dentists have a basic knowledge of the various injuries that affect the jaw bones to prevent errors in diagnosis and treatment and to promote oral health., (Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: Regenerative endodontic treatment is a new and promising approach to manage immature teeth with necrotic pulps and apical periodontitis. The use of scaffolds is essential to treatment success, but many materials are difficult to acquire and have a high cost. This study assessed tissue repair in immature dog teeth with necrotic pulps and apical periodontitis after using a gelatin-based scaffold (Gelfoam; Pharmacia & Upjohn Co, Kalamazoo, MI)., Methods: Apical periodontitis was induced in 20 immature dog teeth. After disinfection with triple antibiotic paste for 2 weeks, canals were irrigated, dried, and filled with a blood clot alone (10 teeth) or combined with Gelfoam (10 teeth). Another 10 teeth were used as negative controls (no intervention). After 7 months, the dogs were euthanized. Histologic sections were stained with hematoxylin-eosin and analyzed in relation to tissue repair. Categoric data were analyzed using the Fisher exact test (P < .05), numeric data (histomorphometric analysis), and the Mann-Whitney U test., Results: Histologic analysis revealed a higher percentage of roots with new cementumlike mineralized tissue and connective tissue inside the canal in the blood clot + Gelfoam group (P < .001). Histomorphometric analysis showed a higher area of mineralized tissue in the same group (P = .029). Apical extension of root and inflammation were similar between the experimental groups. The new tissue formed onto canal walls and in the root canal space showed characteristics of cementum and periodontal ligament, respectively., Conclusions: The use of a gelatin-based scaffold (Gelfoam) combined with a blood clot improved repair in immature dog teeth with apical periodontitis subjected to regenerative endodontic treatment., (Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The objective of this study was to evaluate the efficacy of passive ultrasonic irrigation (PUI) with 17% EDTA and 1% NaOCl solutions on smear layer removal., Methods: Root canal preparations of 32 human teeth were performed with the ProTaper system. Next, they were longitudinally fractured to permit quantitation of smear layer creation from the cervical, middle, and apical thirds of the roots by using scanning electron microscopy. After reassembling the fractured tooth halves, they were divided into 4 groups according to different final irrigation protocols: group1, EDTA + NaOCl; group 2, EDTA with PUI + NaOCl; group 3, EDTA + NaOCl with PUI; and group 4, EDTA + NaOCl, both with PUI. After irrigation, the tooth halves were separated to permit imaging the same areas by scanning electron microscopy, and a percentage of opened dentinal tubules in irrigated areas as a percent of the total area was obtained. The results were submitted to Kruskal-Wallis, analysis of variance, and Bonferroni tests (α = 0.05)., Results: The cervical third of the samples from all groups showed higher percentage of smear layer removal and open dentinal tubule areas, followed by the middle and apical thirds. Among the irrigation groups, there were statistically significant differences in cervical third between group 2 and group 4 samples, with the highest and lowest percentage of smear layer removal, respectively., Conclusions: PUI by using 1% NaOCl and ultrasonic tip placed within 1 mm of the apical foramen did not show higher efficacy in smear layer removal compared with conventional irrigation., (Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)