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Aim: To compare histologically the debridement efficacy of four irrigation techniques in root canals instrumented with a reciprocating single file. Methodology: From recently extracted premolars with vital pulp, 68 were selected and classified as having round canals (mesiodistal diameter similar to buccolingual) or oval‐shaped canals (mesiodistal diameter 2.5 times larger than buccolingual) (n = 32, each) by means of bidirectional radiographs. Four additional uninstrumented samples served as histological controls. The root canals of the specimens were accessed and then instrumented with Reciproc R25® and further assigned to one of four experimental groups according to the complementary irrigation technique: Group I, conventional syringe; Group II, passive ultrasonic irrigation; Group III, manual dynamic activation (MDA); and Group IV, EndoActivator®. Roots were then demineralized and the apical 3 mm was multi‐sliced and processed for histologic examination. The percentage of residual pulp tissue was calculated at each cross section. Kruskal–Wallis and Mann–Whitney tests were used to evaluate the effects of irrigation technique, root canal shape and level of cross section on the percentage of residual pulp tissue (P < 0.05). Results: Irrigation technique and root canal shape significantly influenced the percentage of residual pulp tissue (P < 0.05) of canals instrumented with the R25 instrument. Percentage of residual pulp tissue was significantly less using ultrasonic irrigation (P < 0.05), but there was no difference between other irrigation techniques (P > 0.05). Round canals retained significantly less percentage of residual pulp tissue compared to oval‐shaped canals (P = 0.001). At 3 mm, there was less pulp tissue compared to levels 2 and 1 mm (P < 0.05). Conclusions: In canals instrumented with R25 files, ultrasonic irrigation was more effective in removing pulp tissue in the apical level, especially for the debridement of oval‐shaped canals. [ABSTRACT FROM AUTHOR]

The capacity of glycoprotein (GP) excreted by Pseudoalteromonas antarctica NF[sub 3], to protect phosphatidylcholine (PC) liposomes against the action of the anionic surfactant sodium dodecyl sulfate (SDS) was studied in detail. To this end, changes in the surfactant partitioning between the lipid bilayer and the aqueous phase (partition coefficients, K) and in the effective surfactant to PC molar ratios (R[sub e]) were determined as a function of the amount of GP assembled with liposomes. The permeability of liposomes was determined by monitoring the changes in the fluorescence intensity of liposomes due to the release of the fluorescent dye 5(6)-carboxyfluorescein (CF) from the interior of vesicles to the bulk aqueous phase. Increasing GP amounts in the system resulted in the same interaction step as a rise in R[sub e] and a fall in the surfactant partitioning between the lipid bilayer and water. Hence, the higher the proportion of GP, the lower the surfactant ability to alter the permeability of liposomes and the lower its affinity with these bilayer structures. In addition, increasing GP proportions resulted in the same interaction step as a progressive increase of the free surfactant concentration (S[sub W]). The fact that the S[sub W] was always lower than the surfactant critical micelle concentration indicates that the interaction of SDS with coated liposomes was mainly ruled by the action of surfactant monomers in all cases. [ABSTRACT FROM AUTHOR]

Growth of Pseudomonas aeruginosa strain 44T1 on glucose, an n-alkane mixture or olive oil was characterized by the formation of intracellular lipid inclusions and extracellular accumulation of rhamnolipids. Maximum values of cellular lipid accumulation were obtained in olive-oil-grown cells and reached up to 38% w/w of its dry biomass. The principal fatty acids of cellular lipids drived from P. aeruginosa cultures varied with the carbon source employed. The major fatty acids detected were palmitic and trans-oleic acids. Arachidonic acid was only found in medium containing glucose or the n-alkane mixture. [ABSTRACT FROM AUTHOR]

Aim: To determine the effect of active distraction when playing PlayStation® video games, compared to passive distraction when watching a cartoon with audiovisual eyeglasses, on parental perception of patients' anxiety, and children's anxiety, pain, behaviour and heart rate during restorative procedures in paediatric dentistry., Materials and Methods: Study design: Randomised crossover clinical trial. There were 34 patients in the cartoon film group (passive distraction) and 34 in the Playstation® video game group (active distraction), aged 6-8 years, who required a minimum of 2 visits for restorative treatment. Rimax® iVision 5.0 eyeglasses were used in both groups. Parental perception of patients' anxiety (Modified Corah Dental Anxiety Scale), and children's anxiety (Venham Picture Test), pain (Wong-Baker Faces Scale), behaviour (Frankl Scale) and heart rate were evaluated at each of the treatment visits. Preference for and satisfaction with the audiovisual product were also assessed., Results: There were significant differences in self-reported pain between control (P=0.016) and experimental (P=0.013) visits in both groups, with lower values in the Playstation® video game group. No significant differences were found (P>0.05) in the other variables evaluated with the use of active distraction. A significant increase in heart rate was recorded at each treatment visit (P=0.0001) when the anaesthetic was injected. All the patients wanted to continue watching or playing their chosen cartoon or Playstation® video game during subsequent visits., Conclusion: The use of PlayStation® video games for active audiovisual distraction, compared with passive distraction with a cartoon, improved self-reported pain but did not reduce parents' perception of patients' anxiety, pain, global behaviour, or heart rate. Both distraction methods were accepted by paediatric patients.

Endodontic treatment of teeth with pulp canal obliteration presents a challenge given the high likelihood of procedural errors and complications during treatment. These drawbacks can be avoided by using a personalized 3-dimensional (3D) guide designed by overlaying a cone-beam computed tomographic scan with an intraoral scan of the patient. This 3D guide enables the clinician to obtain a straight access to the obliterated root canal.This article described guided endodontics in managing 7 severely obliterated teeth using both virtually designed 3D guides and a customized 1-mm-diameter cylindrical bur. This treatment approach was demonstrated to be safe and fast and can be considered as a predictable technique for the location of calcified canals, thus minimizing complications., (Copyright © 2020 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objective: This study aims to perform a systematic review and meta-analysis of clinical trials in order to evaluate the clinical and radiographic success rates of primary teeth pulpotomy performed with biodentine, when compared to MTA., Methods: Search strategies were conducted in nine databases on August 5th, 2017, update on February 14th, 2018. Clinical articles were selected, which were in accordance with the inclusion and exclusion criteria and the research objective. They were analyzed by meta-analysis at three time points (6, 12, and 18 months)., Results: Out of the 233 publications initially identified, only 9 studies that fulfilled the inclusion criteria were included in the review. The 6-month overall clinical (RR = 0.99; 95% CI = 0.96-1.02, p = 0.92) and radiographic success rates (RR = 0.96; 95% CI = 0.92-1.00, p = 0.28) showed that biodentine vs. MTA did not differ statistically. The 12 and 18-month overall clinical success rates, respectively (RR = 1.01; 95% CI = 0.97-1.04, p = 0.77; RR = 0.98; 95% CI = 0.92-1.05, p = 0.74) and radiographic success rates, respectively (RR = 0.97; 95% CI = 0.92-1.02, p = 0.11; RR = 1.00; 95% CI = 0.91-1.10, p = 0.56) also showed that biodentine vs. MTA did not differ statistically., Conclusion: There is no superiority of one material over the other, MTA versus biodentine., Clinical Relevance: This systematic review comparing the performance of biodentine in relation to the MTA when used in the pulpotomy technique in primary teeth. Although MTA is considered the gold standard material for pulpotomy procedures, it has some drawbacks (poor handling, staining potential, long setting time); thus, it is important to evaluate the clinical performance of other calcium silicate-based cements like biodentine that overcome this drawbacks.

The aim of this study was to evaluate the WaveOne Gold and One Shape New Generation systems regarding the bacterial removal from root canals infected with Enterococcus faecalis by comparing them to the conventional WaveOne and One Shape systems. Forty-eight distobuccal root canals of maxillary molars sterilized with ethylene oxide were infected with E. faecalis for 21 days, and then root canal initial bacterial sample was collected with paper cones and plated on M-enterococcus agar. The specimens were randomly divided into 4 groups according to the instrumentation: WaveOne Gold, One Shape New Generation, WaveOne and One Shape. After instrumentation, samples were collected with use of scraping and paper cones at immediate and 7 days after instrumentation. The bacterial reduction was calculated and then made intragroup analysis by Friedman test and intergroup analysis by Kruskal-Wallis with Dunn's post-hoc test, all at 5% significance. All techniques significantly reduced the number of bacteria in the root canal (p<0.05). WaveOne Gold and One Shape New Generation promoted higher bacterial reduction than WaveOne and One Shape systems (p<0.05), but no significant difference was found between WaveOne Gold and One Shape New Generation or between WaveOne and One Shape (p>0.05). Novel single-file systems promote better bacterial removal than the conventional single-file systems.

Background: The topographical features on the surface of dental implants have been considered as a critical parameter for enhancing the osseointegration of implants. In this work, we proposed a surface obtained by a combination of shot blasting and double acid etching. The double acid etching was hypothesized to increase the submicron topography and hence further stimulate the biological properties of the titanium implant., Methods: The topographical features (surface roughness and real surface area), wettability and surface chemical composition were analyzed., Results: The results showed that the proposed method produced a dual roughness, mainly composed of randomly distributed peaks and valleys with a superimposed nanoroughness, and hence with an increased specific surface area. Despite the fact that the proposed method does not introduce significant chemical changes, this treatment combination slightly increased the amount of titanium available on the surface, reducing potential surface contaminants. Furthermore, the surface showed increased contact angle values demonstrating an enhanced hydrophobicity on the surface. The biological behavior of the implants was then assessed by culturing osteoblast-like cells on the surface, showing enhanced osteoblast adhesion, proliferation and differentiation on the novel surface., Conclusions: Based on these results, the described surface with dual roughness obtained by double acid etching may be a novel route to obtain key features on the surface to enhance the osseointegration of the implant. Our approach is a simple method to obtain a dual roughness that mimics the bone structure modified by osteoclasts and increases surface area, which enhances osseointegration of dental implants.

Background/purpose: Chelating agents have been used for the removal of the smear layer on teeth. However, due to inadequate volume and/or penetration of the solutions during irrigation, smear layer removal is less effective in the apical third. The purpose of this study was to compare the efficacy of three chelating solutions with and without manual dynamic irrigation in smear layer removal., Materials and Methods: Sixty-six single-root canal teeth were decoronated, instrumented, and divided into six experimental groups ( n  = 10) and two control groups ( n  = 3). The groups received a final rinse with 1 mL of 17% EDTA and 5% or 10% citric acid (CA) for 1 minute, with or without manual dynamic activation, followed by a final 3-mL rinse with 4.2% NaOCl (5 minutes). The teeth were then longitudinally split and prepared for environmental scanning electron microscopy analysis. Digital images (500×) were taken for smear layer removal evaluation at 2 mm, 6 mm, and 10 mm from the working length., Results: The most effective smear layer removal occurred with 5% and 10% CA combined with manual dynamic activation (Groups 7 and 8), where significant differences were observed when compared with the EDTA groups (Groups 2 and 6; P < 0.05). We found no significant differences between manual dynamic activation with 5% and 10% CA (Groups 7 and 8) in smear layer or debris removal (P > 0.05)., Conclusion: Manual dynamic activation of CA improves smear layer removal, and a reduction in CA concentration to 5% does not compromise smear layer removal in comparison with higher concentrations.

Color match and water sorption are two factors that affect restorative materials. Discoloration is essential in the lifespan of restorations. The aim of this study was to evaluate color change and water sorption of nine flowable composites at multiple time points over 6 months. 60 samples of each composite were divided into two groups (Color Change and Water Sorption/Solubility). Each Color Change group was divided into six subgroups, which were immersed in distilled water (DW), coffee (CF), Coca-Cola (CC), red wine (RW), tea (TE) and orange juice (OJ). The color was measured at the baseline, 1, 2, 3 and 4 weeks, and 3 and 6 months and color change values (ΔE) were calculated. Each Water Sorption [WS]/Solubility [WL] group was tested according to ISO 4049:2009. The data were evaluated using two-way ANOVA, Fisher's post-hoc test and Pearson's correlation test. The composite with the lowest ΔE differed for each solution: Filtek™ Bulk Fill in DW (∆E = 0.73 (0.17-1.759)); Vertise Flow in CF (∆E = 14.75 (7.91-27.41)), in TE (∆E = 7.27 (2.81-24.81)) and OJ (∆E = 3.17 (0.87-9.92)); Tetric EvoFlow® in CC (∆E = 1.27 (0.45-4.02)); and Filtek™ Supreme XTE in RW (∆E = 8.88 (5.23-19.59)). RW caused the most discoloration (∆E = 23.62 (4.93-51.36)). Vertise Flow showed the highest water sorption (WS = 69.10 ± 7.19). The Pearson test showed statistically significant positive correlations between water sorption and solubility and between water sorption and ∆E; the positive solubility-∆E correlation was not statistically significant. The findings suggest that water sorption is one factor associated with the ability of composites to discolor; however, discoloration is a multifactorial problem.

Statement of Problem: Prosthodontic treatment sometimes requires a long-term interim fixed dental prosthesis (FDP) until the definitive restoration can be cemented. However, some interim materials are weak and do not have an adequate marginal seal., Purpose: The purpose of this study was to compare the marginal fit and fracture strengths of interim FDPs fabricated by using a direct technique with different materials (Structur 3, Trim, and DuraLay) with interim prostheses (Telio CAD) made with a computer-aided design and computer-aided manufacturing (CAD/CAM) system., Material and Methods: Seventy interim FDPs were fabricated by using different materials (Structur 3, Trim, DuraLay, and Telio CAD) on a metal master model. Resin-impregnated, light-polymerizing glass fiber (GrandTEC) was used to reinforce 10 interim FDPs per material fabricated with the direct technique. Interim FDPs were stored at 37°C for 24 hours before thermocycling. Marginal fit was analyzed at 6 points in each interim FDP before and after thermocycling with either 2500 or 5000 cycles. After fracturing the interim FDPs with a universal testing machine, fracture strength, fragments separation, and fracture point were recorded. Marginal fit data were analyzed with 2-way repeated measure analysis of variance (ANOVA), fracture strength with 1-way ANOVA, and fragments separation and fracture point with the chi-square test at a 99% confidence interval., Results: All interim materials showed marginal discrepancies over time, but no significant differences were found among groups (P>.001), except in the marginal fit of interim FDPs reinforced with glass fiber (S3F), which showed the smallest marginal gap after 5000 cycles (P<.001). Reinforced interim FDPs (S3F, TMF, and DLF) and CAD/CAM FDPs (TCC) presented a fracture strength ranging between 471.3 ±62.4 N and 531.1 ±150.1 N (P>.001). Finally, significant differences were observed in the fracture point and frequency of separation (P<.001)., Conclusions: Bis-acryl reinforced with glass fiber showed the least marginal discrepancy. No differences were found between the fracture strengths of interim FDPs fabricated with CAD/CAM system and interim FDPs reinforced with glass fiber. No significant difference in fracture strength was observed between interim FDPs reinforced with glass fiber and prostheses fabricated with CAD/CAM system. However, unreinforced interim FDPs showed the lowest fracture strength., (Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Introduction: White mineral trioxide aggregate (WMTA) has been reported to cause dental discoloration. A previous study on the color stability of 5 calcium silicate-based materials investigated the color stability of Biodentine (Septodont, Saint-Maur-des-Fossés, France) in different experimental environments; however, no data are available on the color stability of teeth restored with Biodentine. In this study, we assessed the color stability under artificial light of ex vivo human teeth restored coronally with WMTA or Biodentine., Methods: Cavities were prepared on coronal tooth specimens and restored with WMTA + composite (n = 16), Biodentine + composite (n = 16), or composite alone (control, n = 3). Color was assessed spectrophotometrically at 6 time points (initial, 1 week, 2 weeks, 1 month, 3 months, and 6 months), and color difference values were calculated. Statistical analysis was performed using analysis of variance and the Fisher least significant difference test for which P < .05 was considered statistically significant., Results: The WMTA group showed discoloration at 1 week, which increased over time. The Biodentine and control groups showed color stability and were not significantly different from one another., Conclusions: Teeth treated with WMTA exhibited discoloration, whereas those treated with Biodentine maintained color stability throughout the study. However, further in vivo studies are necessary to corroborate these results., (Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objectives: To compare the efficacy of Reciproc(®) (VDW GmbH) and ProFile(®) (Dentsply Maillefer) instruments at removing gutta-percha from straight and curved root canals ex vivo filled using the cold lateral condensation and GuttaMaster(®) (VDW GmbH) techniques., Material and Methods: Forty mesial roots of mandibular molars with two curved canals and 80 single-rooted teeth with straight root canals, a total of 160 root canals, were randomly assigned to eight groups (canals per group = 20) according to filling technique, retreatment instrument and root canal curvature as follows: Group I, cold lateral condensation/ProFile(®)/straight; Group II, cold lateral condensation/ProFile(®)/curved; Group III, cold lateral condensation/Reciproc(®)/straight; Group IV, cold lateral condensation/Reciproc(®)/curved; Group V, GuttaMaster(®)/ProFile(®)/straight; Group VI, GuttaMaster(®)/ProFile(®)/curved; Group VII, GuttaMaster(®)/Reciproc(®)/straight; and Group VIII, GuttaMaster(®)/Reciproc(®)/curved. The following data were recorded: procedural errors, retreatment duration and canal wall cleanliness. Means and standard deviations were calculated and analysed using the Kruskal-Wallis test, one-way analysis of variance and Tukey's test (P < 0.05)., Results: Reciproc(®) instruments were significantly faster than ProFile(®) instruments at removing GuttaMaster(®) from both straight (P = 0.0001) and curved (P = 0.0003) root canals. Reciproc(®) were statistically more effective than ProFile(®) instruments in removing GuttaMaster(®) from straight root canals (P = 0.021). Regardless of filling technique or retreatment instrument, gutta-percha was removed more rapidly from curved than from straight root canals (P = 0.0001)., Conclusions: Neither system completely removed filling material from the root canals. Compared with ProFile(®) instruments, Reciproc(®) instruments removed GuttaMaster(®) filling material from straight and curved root canals more rapidly.

This study provides a morphological characterization of the inner anatomy of the root canals of permanent first and second molars in Chalcolithic and early Bronze Age human fossils using cone-beam computed tomography. The general evolutionary trend in present-day human dentition is related to morphological simplification. As little is known about when this trend appeared in Homo sapiens populations, the aim of this work is to test the presence of modern radicular morphology 4,400 years ago. Fifty-four permanent first and second maxillary and mandibular molars of 17 individuals were included in the study. All maxillary first and second molars showed three separate roots. Almost all the lower molars analyzed (100% of first molars and 75% of second molars) had two separate roots. More differences in the canal system configuration were documented in the maxillary mesiobuccal roots than in the palatal or distobuccal roots. The most variable tooth in root and canal configuration is the maxillary second molar. It should be pointed out that 12.5% of the teeth analyzed showed a C-shaped root configuration., (© 2014 Wiley Periodicals, Inc.)