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Aim: The aim of the study was to investigate the influence of cavity cleaning and conditioning on marginal integrity of directly placed post-endodontic composite class-I-restorations in vitro., Methodology: A total of 168 fully intact teeth without caries or fillings received pre-endodontic composite restorations (class-II) after their extraction. Occlusal endodontic access-cavities were prepared, and root canals were instrumented and filled with gutta-percha and an epoxy resin-based sealer. Prior to post-endodontic class-I-restoration, access cavities were completely contaminated with sealer, cleaned with alcohol and pre-treated as follows: cleaner only (alcohol), glycine-polishing, Al 2 O 3 sandblasting, carbide bur (immediate as well as delayed restoration). A positive control (not contaminated with sealer and adhesive used) and negative control (cleaner used but no adhesive) were established. Half of the teeth from each group were subjected to thermocycling and mechanical loading (TCML). Marginal integrity of post-endodontic restoration was evaluated in oro-vestibular or mesio-distal sections after AgNO 3 dye penetration (DP) by standardized photomacroscopic imaging and expressed in per cent of margin length along all segments and separately for enamel, dentine and composite, respectively. Results were analysed non-parametrically (α = .05)., Results: No restorations or teeth fractured or debonded completely. Without TCML, the median DP of all segments was significantly higher for the negative control compared with all other groups in oro-vestibular cutting direction (53%; p = .002) and in mesio-distal cutting direction (51%; p ≤ .041). The other groups without TCML revealed 16%-24% DP (oro-vestibular) and 12%-24% DP (mesio-distal). With TCML, the median DP in oro-vestibular cutting direction for all segments ranged between 48% and 62% for all groups, a significant difference was only observed between glycine-polishing and carbide bur (p = .041). In mesio-distal cutting direction, the median DP in negative control was 69% with TCML and significantly higher compared with all other groups (p = .002). For all other groups, the median DP of all segments ranged between 28% and 40% with TCML without significant differences. Error rates method (k = 7) revealed a significant influence of TCML in general on penetration of all segments in both oro-vestibular and mesio-distal cutting directions., Conclusion: Additional access cavity pre-treatment after alcohol cleaning did not improve the marginal integrity of post-endodontic composite restorations. Thorough cleaning of the access cavity with alcohol seems to assure an acceptable marginal integrity to the tooth and restorative composite., (© 2022 The Authors. International Endodontic Journal published by John Wiley & Sons Ltd on behalf of British Endodontic Society.)

Background: Fissure sealants prevent occlusal caries in permanent molars. Enamel preparation methods are used before fissure sealing., Aims: To investigate effects of bioglass air-abrasion pre-treatment with and without an adhesive, on fissure enamel of permanent teeth, with respect to etchability, microleakage and microtensile bond strength., Design: Half of the occlusal surfaces of 50 extracted premolars underwent bioglass air-abrasion. Dye was applied to the entire occlusal surface. Photographs were taken to score etched surface by dye uptake. Adhesive was applied to 25 of the bioglass-treated areas and all teeth were fissure sealed, sectioned, and evaluated using confocal microscopy. Buccal and lingual surfaces of a further eight premolars were acid-etched and randomly received: air-abrasion, adhesive, both, or none before sealant application for microtensile bond strength measurement in half of the samples immediately and half following 6 months of water immersion., Results: Linear mixed models and multinomial logistic regression were used (P = 0.05). Bioglass air-abrasion significantly improved enamel etchability and reduced microleakage. The addition of an adhesive made no difference to either microleakage or microtensile bond strength. The combination of bioglass abrasion and adhesive led to more cohesive, rather than adhesive, failure., Conclusions: Bioglass air-abrasion improved enamel etchability and reduced microleakage irrespective of the adhesive use but neither pre-treatment affected the microtensile bond strength., (© 2017 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aim: To compare in vitro the sealing ability of root-end fillings with mineral trioxide aggregate (MTA) and EndoSequence BioCeramic Root Repair Material-Fast Set (BC-RRM) Putty using a novel bacterial nutrient leakage model, which provides information on whether or not intracanal bacteria are receiving nutrients from serum via leakage channels., Methodology: Sixty single-rooted decoronated mandibular incisors with instrumented root canals were subjected to root-end resection and ultrasonic preparation. The root specimens were mounted in the experimental apparatus, and the root-end cavities filled with the test materials. The positive control group used warm Gutta-percha and no sealer. In the negative controls, the entire resected surface was covered with varnish. After sterilization in ethylene oxide, the root canal was inoculated with 1.5 × 10(5) washed cells of Enterococcus faecalis. The apparatus was filled with foetal bovine serum, leaving only the apical root immersed. After 30-day incubation, samples were taken from the canal, cultured and the colony-forming units (CFUs) counted. Statistical analysis was performed using the Mann-Whitney test for quantitative and the Fisher exact test for qualitative data., Results: In the MTA group, 10 of 20 (50%) specimens still had detectable viable bacteria in the canals (mean, 8.97 × 10(3)  CFUs). In the BC-RRM Putty group, 5 of 18 (28%) specimens were positive for bacterial growth (mean, 2.88 × 10(4)  CFUs). There was no significant difference when comparing the quantitative or presence/absence data from the MTA and BC-RRM Putty groups. Positive and negative controls yielded the expected results., Conclusions: MTA and BC-RRM Putty had similar sealing ability. The experimental model was effective in determining whether or not residual intracanal bacteria could survive by receiving nutrients from outside., (© 2015 British Endodontic Society. Published by John Wiley & Sons Ltd.)

Background: The use of external sources of energy may accelerate the setting rate of glass ionomer cements (GICs) allowing better initial mechanical properties., Aim: To investigate the influence of ultrasound and halogen light on the microleakage and hardness of enamel adjacent to GIC restorations, after artificial caries challenge., Design: Cavities were prepared in 60 primary canines, restored with GIC, and randomly distributed into three groups: control group (CG), light group (LG) - irradiation with a halogen light-curing unit for 60s, and ultrasonic group (UG) - application of ultrasonic scaler device for 15s. All specimens were then submitted to a cariogenic challenge in a pH cycling model. Half of sample in each group were immersed in methylene blue for 4h and sectioned for dye penetration analysis. The remaining specimens were submitted to Knoop cross-sectional microhardness assessments, and mineral changes were calculated for adjacent enamel., Results: Data were compared using Kruskal-Wallis test and two-way ANOVA with 5% significance. Higher dye penetration was observed for the UG (P<0.01). No significant mineral changes were observed between groups (P=0.844)., Conclusion: The use of halogen light-curing unit does not seem to interfere with the properties of GICs, whereas the use of ultrasound can affect its marginal sealing., (© 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.)

Aim: To evaluate two nanoparticle-enhanced polymer root-end filling materials (NERP1 and NERP2) on the initial apical seal as compared to a polymer-based commercial compomer., Methodology: One hundred and forty extracted roots with completely formed apices were resected 3 mm from the apex. Cavities were then prepared in the apical openings of the resected root ends using an ultrasonic handpiece to a depth of 3 mm. The roots were then randomly divided into five groups to receive one of five root-end filling materials. Roots in groups 1 and 2 received NERP1 and NERP2, whilst those in groups 3 and 4 received identical polymers as groups 1 and 2 but without nanoparticle addition (RP1 and RP2, respectively). The root-end cavities for the fifth group were filled with commercially available root-end filling compomer. Roots were mounted in a dual-chamber leakage apparatus and inoculated coronally with Enterococcus faecalis. Turbidity of the apical broth was assessed daily for 4 weeks as a sign of initial leakage. The results were statistically analysed using odds ratio and Fisher's chi-square analysis., Results: Nanoparticle-enhanced root-end filling polymer 1 displayed significantly fewer leaked samples compared to all other tested groups as early as 5 days, whilst NERP2 was not significantly different compared to other groups. Odds ratio analysis revealed leakage of the commercial compomer was 12 times more likely than NERP1., Conclusion: Nanoparticle-enhanced root-end filling polymer 1 can reduce apical microleakage significantly under laboratory conditions., (© 2011 International Endodontic Journal.)

Calcium hydroxide has been included within several materials and antimicrobial formulations that are used in a number of treatment modalities in endodontics. These include, inter-appointment intracanal medicaments, pulp-capping agents and root canal sealers. Calcium hydroxide formulations are also used during treatment of root perforations, root fractures and root resorption and have a role in dental traumatology, for example, following tooth avulsion and luxation injuries. The purpose of this paper is to review the properties and clinical applications of calcium hydroxide in endodontics and dental traumatology including its antibacterial activity, antifungal activity, effect on bacterial biofilms, the synergism between calcium hydroxide and other agents, its effects on the properties of dentine, the diffusion of hydroxyl ions through dentine and its toxicity. Pure calcium hydroxide paste has a high pH (approximately 12.5-12.8) and is classified chemically as a strong base. Its main actions are achieved through the ionic dissociation of Ca(2+) and OH(-) ions and their effect on vital tissues, the induction of hard-tissue deposition and the antibacterial properties. The lethal effects of calcium hydroxide on bacterial cells are probably due to protein denaturation and damage to DNA and cytoplasmic membranes. It has a wide range of antimicrobial activity against common endodontic pathogens but is less effective against Enterococcus faecalis and Candida albicans. Calcium hydroxide is also an effective anti-endotoxin agent. However, its effect on microbial biofilms is controversial., (© 2011 International Endodontic Journal.)

Aim: To investigate the impact of dentine conditioning on sealing ability and dentine bond strength of an epoxy resin sealer., Methodology: Root canals in 90 single-rooted teeth were instrumented using a rotary Ni-Ti system. Fifty canals were irrigated with water during instrumentation, 40 with 3% NaOCl. A final flush was performed in the water-irrigated specimens with water (negative control), 3% NaOCl, 17% EDTA, 7% maleic acid (MA) or 2% chlorhexidine. The hypochlorite irrigated specimens received a final flush with a decalcifying agent (EDTA or MA) and then 3% NaOCl or 3% NaOCl and then the decalcifying agent (n = 10, each). Canals were all filled with AH Plus. Fluid transport was measured on day 3 and 30. Roots were then sectioned, and push-out tests were performed in coronal, middle and apical root thirds. Results were analysed using analysis of variance (anova) with Bonferroni's adjustment. Spearman's rank correlation was computed between fluid transport and push-out bond strength., Results: Leakage decreased over time (P < 0.05). Push-out bond strength was highest in coronal and lowest in apical root thirds (P < 0.05). Irrigating protocols with final application of a decalcifying agent greatly decreased the leakage and increased push-out bond strength values, in contrast to groups where NaOCl was applied last (P < 0.05), wherein the effect of the decalcifying agent was abolished. Chlorhexidine had no impact on the outcomes. Fluid transport and push-out bond strength correlated strongly (ρ = -0.83)., Conclusions: AH Plus appears to bond to the organic phase of dentine. This bond influences its sealing ability., (© 2011 International Endodontic Journal.)

Aim: To evaluate bacterial leakage after filling root canals with several endodontic sealers, including MTA-based materials., Methodology: One hundred and thirty single-rooted extracted human teeth were randomly divided into experimental groups (n = 15) and two control groups (n = 5). Six root canal sealers were namely: AH Plus (AHP), Sealer 26 (S26), Epiphany SE (ESE), Sealapex (SEL), Active GP (AGP), Endofill (EDF), and two MTA-based sealers were namely: Endo CPM Sealer (CPM) and MTA-based sealer (MTAS, MTA Sealer). Teeth in the control groups were either filled with no sealer or made completely impermeable. Root canals were prepared and filled with either gutta-percha and one of the sealers or with Resilon and Epiphany SE. Teeth were sterilized by ethylene oxide prior to the bacterial leakage experiments using Enterococcus faecalis. Leakage was evaluated every 24 h for 16 weeks. Data were analysed by the Kaplan-Meier, Kruskal-Wallis and Dunn tests at 5% significance., Results: Control groups had either immediate leakage or no leakage. During 120 days, significantly more leaking samples were detected for AGP, CPM and MTAS (P < 0.05). The best sealing ability was observed for AH Plus and Sealapex (P < 0.05)., Conclusions: All sealers evaluated allowed bacterial leakage. The MTA-based sealers had the most leakage., (© 2011 International Endodontic Journal.)

Aim: To test the antimicrobial efficacy and flow properties of Guttaflow, Epiphany sealer and AH-Plus sealer., Methodology: With the use of Enterococcus faecalis ATCC 29212 as a test organism, both the agar diffusion test (ADT) and direct contact test (DCT) were performed. For DCT, sealers were mixed and placed over the bottom of sterile screw-capped test tubes. A 50 μL bacterial suspension was placed on the tested material samples. Bacteria were allowed to directly come in contact with the sealers for 1 h at 37 °C in one group and for 24 h in the other group. The suspensions were then diluted and inoculated over blood agar plates, and bacterial colony counts were determined with the use of a digital colony counter. The data in both 1- and 24-h groups were individually analysed using repeated measures ANOVA. Kruskal Wallis tests were further used to obtain comparison between 1- and 24-h results for all three sealers. In the flow assay, the sealers were placed between two glass slides, and a weight of 500 g was placed on the top of the glass. The diameters of the formed discs were recorded., Results: For both the ADT and DCT tests, Epiphany and AH-Plus sealer reduced the bacterial counts significantly (P = 0.000). Epiphany produced a greater reduction in bacterial counts when compared to AH-Plus in both the tests (P = 0.000). Guttaflow paste failed to show any antibacterial activity in both ADT & DCT. According to the flow test, all root canal sealers flowed; Epiphany sealer had the maximum flow under the given conditions, followed by AH-Plus sealer and Guttaflow paste., Conclusions: Antimicrobial activity of the sealers was greatest for Epiphany followed by AH-Plus sealer and Guttaflow. Epiphany sealer had the maximum flow followed by AH-Plus sealer and Guttaflow., (© 2010 International Endodontic Journal.)

Aim: To evaluate the sealer/dentine interface associated with an epoxy resin sealer using the combination of Goldner's trichrome stain (GTS) and scanning electron microscopy (SEM) to verify the use of the experimental methodology., Methodology: Extracted human maxillary incisors (6) were subjected to root canal treatment. Subsequent to pulp removal, canal instrumentation and smear layer removal using EDTA and NaOCl, teeth were randomly and equally assigned to a 'wet' or 'dry' group. The 'dry' group was desiccated (95% ethanol/suction/paper points/air-drying), whilst the 'wet' group was treated with a saline rinse/suction/single paper point. Canals were then filled with an epoxy-based resin sealer and warm vertical gutta-percha compaction. After 7-day storage at 37°C, roots from each group were sectioned into apical, middle and coronal horizontal subsections that were cut and split into paired halves and evaluated with GTS or SEM. With GTS sections, hybrid layer and sealer tubular penetration were measured (n=15 measurements/intracanal location/condition) and evaluated using a two-factor repeated measures analysis of variance. The SEM qualitative analysis of paired sections was included as a complementary confirmation of GTS analyses., Results: In dry and wet groups, there was no conspicuous sealer/dentine interface hybrid layer, irrespective of canal location. However, dry specimens exhibited more uniform sealer distribution with deeper tubular penetration in the coronal and middle third (P<0.05). In contrast, there was decreased sealer distribution and tubule penetration in the apical third, regardless of moisture condition (P<0.05)., Conclusions: The experimental methodology (combination of GTS and SEM) can be used to evaluate the intracanal resin sealer/dentine interface. The pilot data indicated that thorough drying of the root canal system may result in improved epoxy resin sealer distribution and deeper resin sealer tubular penetration, especially in the coronal and middle thirds of root canals., (© 2010 International Endodontic Journal.)

Aims: To evaluate (i) the sealing ability of two sealers, mineral trioxide aggregate sealer (MTAS) and Pulp Canal Sealer (PCS), used with gutta-percha utilizing the fluid filtration method, (ii) leaching and surface characteristics in Hank's balanced salt solution (HBSS) over a period of time., Methodology: Surface characteristics in HBSS were evaluated under the scanning electron microscope after 1 and 28 days, and the leaching of both sealers were assessed by inductively coupled plasma atomic absorption spectrometry (ICP-AAS). In addition, 24 single rooted extracted teeth were root filled using warm vertical compaction with either MTAS or PCS used as sealers with gutta-percha. Four teeth were used as positive and negative controls. Sealing ability was evaluated after 1 or 28 days using the fluid filtration method., Results: Mineral trioxide aggregate sealer exhibited crystalline deposits rich in calcium and phosphorus on its surface when in contact with a physiological solution. These crystalline deposits were absent in PCS and on MTAS stored at 100% humidity. The sealing ability of MTAS was similar to that of PCS., Conclusions: The novel sealer based on mineral trioxide aggregate had comparable sealing ability to a proprietary brand sealer cement. In contact with a simulated body fluid, the MTA sealer released calcium ions in solution that encouraged the deposition of calcium phosphate crystals., (© 2010 International Endodontic Journal.)

Aim: To evaluate the ability of two resin-based filling materials to provide immediate and long-term sealing of the root canal., Methodology: A total of eighty-two human roots were instrumented and filled with AH Plus/gutta-percha or Epiphany/Resilon. Root filled teeth were sealed coronally either with Coltosol or Clearfil SE Bond/Filtek Z250 or were left unsealed. The quality of root canal sealing was assessed by a fluid filtration method performed at immediate and 180-day time intervals. Mean fluid filtration rates were analyzed by three-way repeated measures anova and Tukey post hoc test., Results: Specimens filled with Epiphany/Resilon exhibited higher leakage than specimens filled with AH Plus/gutta-percha (P < 0.05), regardless of the coronal sealing condition and period of evaluation. No difference was detected between coronal restorative materials (P > 0.05), whilst leakage in teeth without any coronal restoration was significantly higher (P < 0.05). After storage, a significant decrease in leakage (P < 0.05) was observed in all experimental groups., Conclusions: AH Plus/gutta-percha provided superior root canal sealing at both immediate and 180-day time periods. The presence of a coronal seal reduced leakage significantly. Storage of root filled specimens did not disturb the sealing ability of the tested materials.

Aim: To evaluate bacterial leakage of Apexit Plus, a new root canal sealer, in comparison with AH Plus., Methodology: A total of 56 single-rooted human teeth were randomly divided into two experimental groups of 16 roots and two control groups. Roots were filled by lateral condensation with Gutta-percha and AH Plus or with Gutta-percha and Apexit Plus. A split chamber microbial leakage model was used in which Streptococcus mutans placed in the upper chamber could reach the lower chamber only through the filled canal. Positive controls were filled only with Gutta-percha and tested with bacteria, whereas negative controls were sealed with wax to test the seal between chambers. Additionally, film thickness, solubility and dimensional change were determined., Results: All positive controls leaked within 24 h, whereas none of the negative controls leaked after 30 days. Apexit Plus had significant less bacterial leakage (log-rank test, P < 0.0001) than AH Plus. AH Plus (0.3% solubility) showed a slightly lower solubility than Apexit Plus (0.5% solubility) but a larger film thickness (28 vs. 11 mum) according to ISO 6876:2001., Conclusion: Apexit Plus had a better sealing ability in comparison with AH Plus.

Aim: To evaluate the percentage of gutta-percha and sealer-filled canal area when four different types of master gutta-percha cones were used., Methodology: Sixty mandibular premolars with straight canals were instrumented using System ProTaper rotary instruments with a crown-down technique and assigned to four groups. Canals were obturated with AH-26 sealer either using lateral condensation and 0.02 taper gutta-percha cones (group A), 0.04 taper gutta-percha cones (group B), nonstandardized F- medium (group C) master gutta-percha cones, or a single System ProTaper gutta-percha cone (group D). The percentage of gutta-percha and sealer-filled area was calculated in horizontal sections of the apical portion of each canal, using image analysis software. The data was statistically analysed using Kruskal-Wallis test., Results: The distribution of filling materials amongst groups was not significantly different at each level of sectioning (P > 0.05)., Conclusion: The percentage of gutta-percha and sealer-filled canal area was similar when canals were filled with different master cones using lateral condensation or single cone techniques.

Aim: To evaluate the resistance to ex vivo bacterial leakage over a 40-day period of root canal fillings with five new root canal sealers: RC Sealer, Epiphany, EndoREZ, GuttaFlow and Acroseal, compared with Apexit, AH Plus and RoekoSeal., Methodology: One hundred and forty-four single rooted human teeth were divided randomly into eight test (n = 15) and two control groups (n = 12). The root canals were filled using a single cone technique with gutta-percha except in the Epiphany and EndoREZ groups. These were filled with Resilon and resin-coated gutta-percha, respectively. The gutta-percha surface of the GuttaFlow group was coated with an experimental primer prior to filling. Positive controls were filled with gutta-percha without sealer and tested with bacteria, whereas negative controls were sealed with wax to test the seal between the chambers. Filled roots were incorporated in a split chamber model system using Streptococcus mutans as a microbial marker. Leakage was assessed for turbidity of the broth in the lower chamber every day for 40 days. Survival analysis was performed using the Kaplan-Meier product limit method and event times were compared using the Log-rank test (alpha = 0.05)., Results: Epiphany, GuttaFlow with test primer and Apexit prevented leakage significantly better than AH Plus, RC Sealer, RoekoSeal, EndoREZ and Acroseal (P < 0.05). None of the specimens in the AH Plus, RC Sealer, RoekoSeal and EndoREZ groups resisted bacterial penetration for 40 days., Conclusion: The new sealers, Epiphany and GuttaFlow with primer, along with Apexit, showed better resistance to bacterial penetration than the other new or traditional sealers tested.

Aim: To compare the sealing ability and the canal-filled area (gutta-percha + sealer) of three current filling techniques in oval-shaped canals., Methodology: A total of 50 oval-shaped root canals were prepared and root filled as follows: G1: lateral condensation (n = 10), G2: System B (n = 10) and G3: Thermafil system (n = 10). All teeth were mounted in a two-chamber apparatus and the coronal access was exposed to human saliva. The appearance of turbidity in the BHI broth over a 15-week period was observed. A cross section of each tooth was made 5 mm from the apex and the samples were prepared for microscopic analysis. Digital image measurements of the cross-sectional area and the area filled by gutta-percha and sealer were performed. Log-rank and Fisher's exact tests were used to analyse the leakage data. Student's t-test was used to analyse the filled-area data., Results: Overall, 30% of the specimens of G1 and G2 and 20% of G3 demonstrated leakage after 15 weeks and no significant difference was found amongst the groups (P > 0.05). The percentage of canal-filled area was 68, 70 and 78%, respectively (P > 0.05). The correlation analysis revealed no significant relation between the pattern of bacterial leakage and canal-filled area (P = 0.128)., Conclusions: No significant difference in apical sealing and canal-filled area in oval-shaped canals was seen between the three filling techniques. No significant correlation was found between the quality of the apical seal and the filled-area of the root canal space.

Aim: To evaluate the long-term sealing ability of four contemporary endodontic sealers [Pulp Canal Sealer (PCS), AH-Plus, GuttaFlow and Epiphany] using a fluid filtration technique., Methodology: The palatal roots of 40 human maxillary molar teeth were selected and the root canal was prepared using a crown-down technique (apical size 40, 6% taper). Roots were irrigated with 3% NaOCl, 17% EDTA solution and rinsed with distilled water. Canals were filled with either PCS, AH-Plus, GuttaFlow or Epiphany using a single-cone technique (n = 8). Twenty-four hours after filling, the roots were connected to an automatic flow-recording device (Flodec System) filled with double-distilled water under pressure (0.2 bar) to measure leakage. Flow rates were assessed at 6, 12 or 24-h and after 1-year of storage., Results: None of the materials fully prevented fluid flow. Fluid flow decreased after 6 h and decreased further after 12 h. After 24 h, PCS and AH-Plus allowed significantly more fluid flow than GuttaFlow and Epiphany. After 1 year, PCS allowed significantly more fluid flow than the other materials. No significant changes in leakage occurred between 24 h and 1 year., Conclusions: GuttaFlow and Epiphany allowed less fluid movement along filled straight roots.

Aim: To compare systematically the sealing ability provided by four endodontic cements: AH Plus, Pulp Canal Sealer EWT, RoekoSeal and GuttaFlow., Methodology: A sample of 100 human mandibular incisors with oval-shaped canals was selected from an initial sampling of two hundred teeth. The root canals in 80 teeth were prepared and filled by the same operator using the cold lateral compaction technique with one of the following four cements (n = 20): G1: AH Plus; G2: Pulp Canal Sealer EWT; G3: RoekoSeal and G4: GuttaFlow. Ten teeth with intact crowns served as negative controls and 10 teeth that were not root filled served as positive controls. All teeth were mounted in a two chamber apparatus and then exposed to human saliva. The number of days over a 9-weeks-period was recorded for the appearance of turbidity in the BHI broth. A Log-rank test was used to analyse the leakage data., Results: Overall, 30% of the samples of the AH Plus group (G1) and 35% of the Pulp Canal Sealer EWT group (G2) were fully contaminated after 9 weeks, whereas 15% of RoekoSeal (G3) and GuttaFlow (G4) groups were fully contaminated. There was a significant difference between (G1/G2) and (G3/G4) (P < 0.05). There was no significant difference between G1 and G2 or between G3 and G4 (P > 0.05)., Conclusion: The silicone-based sealers revealed the best results throughout the experimental period. Leakage patterns of AH plus and Pulp Canal Sealer were statistically similar.

Aim: To compare the long-term apical sealing ability of gutta-percha/AH Plus and Resilon/Epiphany., Methodology: The root canals of 90 single-rooted human mandibular premolars with single narrow root canals were prepared with ProFile 0.4 taper instruments to apical size 40. After each instrument, the canals were irrigated with 1% sodium hypochlorite. Subsequently, the teeth were randomly divided into four groups containing 20 teeth each. Additionally, 10 prepared premolars served as positive and 10 counterparts with intact crowns as negative controls. The root canals were filled with gutta-percha/AH Plus or Resilon/Epiphany using lateral or vertical compaction. Specimens were allowed to set for 7 days at 37 degrees C and 100% humidity. Subsequently, the root fillings were removed down to the apical 4 mm. Fluid movement was then assessed using a fluid transportation model and re-evaluated after 16 months of water storage. Leakage within and between groups was compared using nonparametric tests., Results: Negative controls revealed no fluid movement and positive controls displayed gross fluid movement at both times of observation. At the immediate measurement, there were no significant differences between the experimental groups (Kruskal-Wallis, P > 0.05). Gutta-percha/AH Plus fillings retained their seal after 16-months storage (Wilcoxon, P > 0.05), whilst the Resilon/Epiphany groups lost their sealing capacity (Wilcoxon, P < 0.001). In these groups, 29 of the 40 specimens exhibited gross leakage similar to positive controls., Conclusion: Initially, Resilon/Epiphany root fillings prevented fluid movement to the same degree as gutta-percha/AH Plus counterparts, but showed more fluid movement when tested at 16 months.

Aim: To evaluate the flow characteristics of AH Plus, Epiphany Root Canal Sealant, Endométhasone, Pulp Canal Sealer (EWT) and Sealapex and their ability to fill artificial lateral canals and prevent microleakage., Methodology: Flow of the sealers was analysed using the American Dental Association (ADA) 57 and the International Standards Organization (ISO) 6,876 specifications. Two lateral canals were produced in the middle and apical third of 64 roots using 0.1 mm cylindrical drills. Lateral condensation of gutta-percha or Resilon and one or other of the sealers were used to fill the root canals. Buccal-lingual digital radiographs were exposed. After the sealer had set, the roots were immersed in Indian ink and cleared in methyl salicylate. The extent of filling and dye penetration were measured on the buccal and lingual root surfaces under 30 x magnification with a stereoscope., Results: AH Plus, Epiphany and Pulp Canal Sealer (EWT) complied with ADA 57 and ISO 6,876 specifications. Sealapex complied with the ADA 57 specification but not with ISO 6,876. Endométhasone did not comply with either specification. Filling of lateral canals was similar for the five sealers tested. Dye leakage demonstrated that AH Plus, Epiphany and Sealapex permitted less leakage than Pulp Canal Sealer (EWT) (P < 0.05)., Conclusions: All the sealers flowed into the 0.1 mm artificial lateral canals. AH Plus, Epiphany and Sealapex allowed less linear leakage than Pulp Canal Sealer (EWT). The flow of Endométhasone did not comply with either ADA 57 or ISO 6,876 specifications and Sealapex did not comply with ISO 6,876.

Aim: To compare the sealing of root canals filled with two single-cone obturation systems and a warm vertical compaction technique., Methodology: Forty-two single-rooted teeth were decoronated to obtain 17-mm-long root segments. The root canals were cleaned and shaped to size 40, 0.06 taper and filled with: (i) warm vertical compaction with AH Plus (control); (ii) ActiV GP and (iii) GuttaFlow with single master cones. Leakage was evaluated by fluid filtration at 10 psi before root resection, and after 3, 6, 9 and 12 mm apical resections. Repeated measures anovas on ranks and Dunn's multiple comparison tests were performed to examine differences in fluid flow rates amongst different resection lengths for each filling technique. The surface and interior aspects of glass-ionomer filler-coated ActiV GP gutta-percha cones was evaluated with SEM., Results: No statistical difference amongst the filling techniques was seen at 0 and 3 mm root resections. ActiV GP and GuttaFlow exhibited more leakage than AH Plus at 6, 9 and 12 mm resections. AH Plus recorded the best overall results. A nonhomogeneous coating of glass-ionomer fillers on the surface of ActiV GP cones was detected., Conclusions: The two single-cone techniques examined are as effective in sealing the apex as AH Plus when the latter was used with warm vertical compaction. It is further hypothesized that the inferior coronal seal of these single-cone techniques may be improved with the placement of accessory cones to reduce sealer thickness or an immediate coronal adhesive restoration.

Aim: To evaluate the influence of passive ultrasonic irrigation (PUI) on the seal of root canal fillings., Methodology: A total of 40 mandibular premolars were distributed equally into two groups and the root canals were cleaned and shaped; they were then filled with gutta-percha and AH26 (sealer) using the warm vertical compaction technique with the System B (Analytic Technology, Redmond, WA, USA) device. In one group PUI was applied, after completion of instrumentation and hand-irrigation. In the other group, PUI was not applied. Thereafter, leakage of glucose was evaluated by measuring its concentration once a week for a total period of 56 days using a glucose penetration model. Differences between the groups in terms of glucose concentrations were statistically analysed with the Mann-Whitney test; the level of significance was set at P=0.05., Results: After the first month the root fillings in teeth where PUI had been used, sealed the root canal significantly better than in teeth where no PUI had been used (P=0.017)., Conclusion: Root fillings sealed the root canal better when PUI had been used.

The aim of this study was to examine the effectiveness of single-step self-etching adhesives in preventing nanoleakage over a 90-day water-storage period, and analyse the ultramorphological characteristics of resin-dentin interfaces. Three single-step self-etching adhesives were evaluated: Adper Prompt L-Pop - LP (3M ESPE), iBond - iB (Heraeus Kulzer), and Clearfil Tri-S Bond - S3 (Kuraray). Bonded specimens were sectioned into 0.9-mm thick slabs and stored in water for 1, 60 or 90 days. After the storage periods, a silver tracer solution was used to reveal nanometer-sized spaces and evidence of degradation within resin-dentin interfaces. Epoxy resin-embedded sections were prepared, and the interfaces observed with the TEM. Nanoleakage patterns were compared among adhesives and storage periods using image analysis software. Data were statistically analysed by two-way anova and Tukey test. Nanoleakage was observed in all resin-dentin interfaces produced by the single-step self-etching adhesives. Results showed that LP presented the lowest silver deposition means at 1 day. However, after 60 and 90 days, the area of silver deposition significantly increased for LP. iB presented intense silver deposition after 1 day and a small increase after 90 days. S3 presented the lowest silver deposition means after 60 and 90 days of water-storage.

Aim: To evaluate the sealing ability of calcium sulphate when used under composite resin for the repair of furcation perforations having different diameters., Methodology: Perforations of different diameter were created in the floors of pulp chambers in 60 extracted human molar teeth with either a number 3 (1 mm diameter) or 5 (1.5 mm diameter) round bur. The specimens of each group were divided into four sub-groups which were repaired with composite resin either alone or in combination with calcium sulphate that created an artificial floor (15 teeth group(-1)). Eight teeth without furcation perforations served as negative controls. In the leakage detection device, 1 mol L(-1) glucose solution was forced under a pressure of 1.5 KPa from the crown towards the pulp chamber floor. The concentration of leaked glucose was measured at 1, 2, 4, 7, 10, 15 and 20 days using a glucose oxidase method and the data evaluated using the rank sum test., Results: The specimens with larger perforations repaired with composite resin alone had significantly more leakage (P < 0.05). Using calcium sulphate as an artificial floor significantly decreased leakage of smaller perforations (P < 0.05). In groups repaired with calcium sulphate under composite resin, leakage in smaller perforations was markedly lower than that in larger ones (P < 0.05). No significant difference was found between the specimens with 1 or 1.5 mm perforations repaired with resin alone (P > 0.05)., Conclusions: Calcium sulphate significantly improved the sealing ability of 1 mm perforations repaired with composite resin but not for 1.5 mm perforations.

Objectives: The aim of the present study was to evaluate the effect of a thin layer of flowable composite on microleakage in Class II direct packable composite resin restorations on young permanent teeth in vitro., Methods: Twenty sound human premolars and molars extracted for orthodontic reasons were selected for this study. The teeth were randomly assigned into two groups of 10 teeth each (groups A and B). Class II cavities were prepared as uniformly as possible in the mesial and distal aspects of each tooth. The gingival margin extended apically approximately 0.5 mm beyond the cemento-enamel junction, in the dentin. Cavities in group A were restored with packable composite and Alert/Flow-it flowable composite, while groups B cavities were restored with Pyramid/Aeliteflo. The control cavities in groups A1 and B1 were restored with only packable composite. The teeth were immersed in 2% methylene blue solution for 24 h to allow dye penetration into possible existing gaps between the tooth substance and the restorative material. All teeth were subjected to thermocycling., Results: The dye penetration ranged between 6.6 and 7.2 mm. No significant difference was found between the control and the experimental groups., Conclusion: The use of flowable composite resin as intermediate material does not reduce microleakage.

Objectives: A pilot study aimed to compare the microleakage of pit and fissure sealants in acid-etched and Erbium:Yttrium Aluminium Garnet (Er:YAG)-treated enamel., Methods: Forty permanent noncarious young molars and premolars, which were extracted for orthodontic reasons, were selected. The teeth were divided into four groups, with five molars and five premolars in each group. The groups were treated as follows: (1) group A--laser irradiation of the enamel of the occlusal surface without contact and in scanning mode was carried out using an Er:YAG laser, placement of sealant material, light curing, and thermocycling between 6 degrees and 55 degrees C; (2) group B--the same as group A, but with no thermocycling; (3) group C--acid etching of the enamel surface, placement of sealant material, light curing and thermocycling; and (4) group D--the same as group C, but with no thermocycling. After being immersed in 1% methylene blue solution, all teeth were sectioned in the mesio-distal dimension into four slices. Images of the slices were then scanned to a Macintosh G3 computer and examined for marginal leakage. Leakage was measured by the degree of dye penetration. Three independent examiners evaluated the dye penetration., Results: No penetration of dye material was observed in any of the slices in any of the four groups by any of the examiners., Conclusions: No difference in microleakage was seen between lasing or acid etching, and therefore, the results of the present study would suggest that the technique may be efficacious.

Aim: To evaluate the apical seal of canals filled with a core-carrier obturator following root-end resection with and without a root-end filling., Methodology: Thirty single-rooted human teeth with single canals were used. Root canal treatment was performed and canals filled with a core-carrier obturation technique. The teeth were then randomly assigned to three groups (n = 10). In the first group root canal filling only was performed. After orthograde filling, the teeth of the second group were resected apically, perpendicular to the major axis of the root. In the third group after apical resection, a root-end cavity was prepared using ultrasonic diamond retrotips and the cavities filled with Super-EBA cement. During a period of 3 h and with a headspace pressure of 0.12 atm, methylene-blue solution was forced through a tube that was connected to the apical end of each tooth specimen. The coronal end of the tooth was connected to a capillary tube containing an air bubble. Leakage was evaluated by observing the distal displacement of the air bubble. The roots were then sectioned along their long axis. Using a stereomicroscope, linear dye infiltration at the dentine-cement interface was determined. Kruskal-Wallis and Mann-Whitney tests were used to compare the three groups., Results: Linear dye infiltration was significantly greater in root canals filled with the core-carrier obturators and resected apically (0.9 +/- 0.9 mm) when compared with those that had root-end fillings (0.2 +/- 0.4 mm). Air bubble displacement was not observed., Conclusion: Root-end filling improves the sealing of roots with core-carrier obturation following root-end resection.

Objectives: This study evaluated the effect of pumice prophylaxis on the level of microleakage around and between the sealant and enamel., Materials and Methods: A total of 32 freshly extracted sound upper first premolars, assigned as suitable for sealant application, were chosen and divided randomly into two groups: (1) a test group, without prophylaxis; and (2) a control group, with prophylaxis. Sealant was applied to all teeth using the same conventional technique, with prophylaxis being omitted in the test group. The sealed teeth were thermocycled (120 x 30 s, 5 and 55 degrees C cycles) and then immersed in 2% Basic Fuchsin solution for 72 h. Each tooth was sectioned and examined for dye penetration under a stereomicroscope (x 60 magnification)., Results: No dye penetration was seen in 19 (29.6%) of the teeth in the test group and 36 (56.2%) of the teeth in the control group. Dye had penetrated to the base of the fissure in 31 (48.4%) of the teeth in the test group and 23 (35.9%) of the teeth in the control group. Using a chi-square test for trend, the frequency of microleakage was significantly higher in the test group compared to the controls (P < 0.016)., Conclusion: Prophylaxis has a role in improving sealant retention. Removing this step may cause an increase in microleakage.

Aim: To compare in vitro the sealing properties of five different dentine adhesive materials (Prime&Bond NT (PBNT); Prompt L-Pop (PLP); Clearfil SE Bond (CSEB); Scotchbond Multi Purpose Plus (SMPP); EBS-Multi (EBSM)) inside the pulp chamber., Methodology: Seventy-five recently extracted human molar teeth were used. The roof of the pulp chambers and roots were removed under water cooling. Pulp tissue was removed, and the canal orifices were sealed. The pulp chambers were then treated with 5% sodium hypochlorite (NaOCl) for 1 min. The teeth were randomly divided into five groups of 15 teeth each. Adhesive systems were applied to the pulp chamber walls according to the manufacturers' instructions. The samples were connected to Plexiglass plates, and a fluid filtration method was used for quantitative evaluation of leakage. Measurements of fluid movement were made at 2-min intervals for 8 min. The quality of seal of each specimen was measured immediately, after 24 h, 1 week and 1 month. The data were statistically analysed by repeated-measurements multivariate anova, Friedman test, Wilcoxon signed rank test, Kruskal-Wallis of one-way anova and Mann-Whitney U-tests. The pulp chamber wall with and without NaOCl and resin-dentine interfaces of specimens were observed under a scanning electron microscope (SEM)., Results: The leakage values of the materials were significantly different at different measurement periods. In all groups, leakage values decreased with time (P < 0.05). PBNT and PLP had the least leakage during immediate measurements (P < 0.05). After 1 month, leakage of all adhesive systems was not significantly different (P < 0.05). SEM observation of pulp chamber walls demonstrated that the irregular dentine surface without smear layer was present in the nontreated group. However, NaOCl application removed the collagen fibrils leaving the dentine surface smooth. At resin-dentine interfaces of specimens, no hybridization zone was observed., Conclusions: None of the materials had created a perfect seal to the pulp chamber walls. PBNT and PLP had better sealing over the short term, but over the long term, there were no differences between the materials.

The purpose of this study was to evaluate the microleakage characteristics of laminate veneers with different incisal edge preparation. Two groups of 20 extracted human maxillary central incisors were used for fabricating laminate veneers. The cervical margin of all veneers were placed 1 mm above the cementoenamel junction. The incisal finish line of 20 teeth was placed at the incisal edge (window type preparation). The incisal finish line of the other 20 teeth was placed linguoincisally (incisal edge overlapped type preparation). All veneers were fabricated according to the manufacturer's instructions with vacuum fired porcelain and cemented with dual-cure resin cement. The autoradiographic method was used for determination of microleakages. Microleakages at the interface of the laminate veneer and tooth were determined according to the scale described in the manuscript. Mc Nemar test was used for comparison of microleakages at cervical margins. Microleakage grades at other areas were compared in percentage. In the two preparation types the cervical microleakages were of similar degree. The incisal microleakages in the overlapped laminate veneers were greater than in the window type veneers. In conclusion, the window preparation type was more effective in terms of prevention of microleakage at the incisal margin than the overlapped type laminates.

The purpose of this in vitro study was to examine the coronal leakage of canals medicated with Ca(OH)(2) compared with the canals which did not receive Ca(OH)(2) medication before obturation with laterally condensed gutta-percha points and sealer. Sixty-one single rooted permanent canines and premolars were used. The crowns were removed from the cemento-enamel junction. After the canals were chemomechanically prepared, the roots were divided into three experimental groups as group 1, 2 and 3. The canals in group 1 and 2 were treated with ethylenediaminetetraacetic acid (EDTA) and NaOCl in order to remove the smear layer and then the canals were filled with Ca(OH)(2) paste. The coronal 3 mm of the cavities were sealed with Cavit and the samples were kept in an incubator at 37 degrees C for 7 days. No intra-canal medication was applied in group 3. The root canals were irrigated with NaOCl in group 1 and with EDTA and NaOCl in group 2, in order to remove Ca(OH)(2) before obturation. Two samples from group 1 and two from group 2 were examined under SEM in order to reveal the removal of Ca(OH)(2) paste. Following this, the canals in the experimental groups were obturated with gutta-percha and sealer. The roots were placed in India ink for 7 days and the linear dye penetration was evaluated. No significant statistical difference was found in the amount of coronal dye leakage between experimental groups (P > 0.05). The results of the present study indicated that the application of Ca(OH)(2) as a temporary dressing material had no effect on coronal leakage.

The capacity to bond to dental tissues, especially to dentine, their long-term fluoride release and their biocompatibility make glass ionomer cements (GICs) advantageous for use in endodontics, as well as in restorative dentistry. This review provides information on the basic properties of GICs, such as adhesion, antimicrobial effects and biocompatibility, particularly as they relate to use in endodontics. Indications for the use of GICs in endodontics are orthograde root canal sealing, root-end filling, repair of perforations and root resorption defects, treatment of vertical fractures and maintenance of the coronal seal. The paper includes a review on each of these indications. It is concluded that in spite of the critical handling characteristics and the inconclusive findings regarding sealing ability and antimicrobial activity, there is substantial evidence to confirm their satisfactory clinical performance. Both soft tissue and bone compatibility make them suitable for use during endodontic surgery.

Aim: To compare fluid movement (FM) along the coronal two-thirds of gutta percha/sealer root fillings placed by three different techniques., Methodology: Three groups consisting of the roots of mandibular incisors were instrumented and obturated by cold lateral compaction (LC), warm vertical compaction (VC) or the single-cone technique (SC), using RoekoSeal Automix (RSA) as the sealer. The apical 4 mm of each root filling was removed, and FM along the remaining 7 mm of the root filling was measured., Results: The VC group displayed more FM than the other two groups (P = 0.023). No significant difference in FM was found between the LC and SC groups (P = 0.629)., Conclusions: The coronal two-thirds of the VC root fillings did not prevent FM when RSA sealer was used.

Aim: The purpose of this study was to collect quantitative information about the numbers and dentine bridge secretory activity of odontoblast-like cells following dental pulp exposure., Methodology: The numbers and secretory activity of odontoblast-like cells were measured histomorphometrically between 7 days and 2 years in 161 pulp-exposed nonhuman primate teeth. The area of dentine bridges and the dimensions of cavity preparations were measured. The density of odontoblast-like cells and subjacent reorganizing tissue cells were measured beneath dentine bridge formation. The presence of operative dentine debris and tunnel defects in bridges was noted. Pulp inflammation was categorized according to ISO standards. Bacteria were detected using McKay's stain., Results: The area of dentine bridges was mediated by the density and secretory activity of odontoblast-like cells over time. The cell density of subjacent reorganizing tissue was found to be strongly associated with that of odontoblast-like cells. Bacterial microleakage was found to impede dentine bridge secretion by odontoblast-like cells., Conclusions: Pulp reparative activity occurs naturally beneath capping materials in the absence of bacterial microleakage. The outcome of pulp-capping treatments could be beneficially influenced by concentrating attention on limiting the width of pulp exposure, minimizing pulp injury by limiting the creation of operative debris and placing materials which prevent bacterial microleakage.

Teeth undergoing root-canal therapy are susceptible to microbial contamination from oral fluids both during and after treatment. With the exception of single-visit treatment, the use of a temporary restoration is mandatory. This review aims to provide an overview of the materials and techniques used for short- and long-term restorations during and immediately after endodontic treatment, and to make clinical recommendations. Further research is necessary to determine the effectiveness of temporary restorations in the conditions of the oral environment, especially with respect to leakage and functional demands.

Aim: This in vitro study evaluated the microleakage of root fillings involving four root-canal sealers including AH Plus (De-Trey, Switzerland), RoekoSeal (Roeko, Germany). Ketac-Endo (ESPE, (Germany) and Sultan (Sultan Chemists, USA., Methodology: Forty extracted human maxillary anterior teeth were used. The coronal part of each tooth was removed and the root canals were prepared using the step-back technique and apical enlargement to size 60 file. The specimens were randomly divided into four groups of 10 samples, filled with one of the test materials and gutta-percha cones by the cold lateral condensation technique. A fluid filtration method was used for quantitative evaluation of apical leakage. The leakage was measured by the movement of an air bubble in a capillary glass tube connected to the experimental root section. Measurements of fluid movement were made at 2-min intervals for 8 min. Water transport through existing voids in the obturated canals could be measured reproducibly in this way. The quality of the seal of each specimen was measured after 7,14 and 21 days., Results: Statistical analysis indicated that all the root fillings showed less leakage after 21 days (P < 0.05). Fillings incorporating Sultan showed significantly more leakage than all other sealers., Conclusions: Root fillings with RoekoSeal in combination with cold lateral condensation technique showed better sealing than those with Ketac-Endo, AH Plus and Sultan sealers after 21 days. The fluid filtration test used in this study gave quantitative results and allowed nondestructive long-term evaluation of specimens.

Aim: To assess the ability of IRM, Coltosol, Vidrion R and Scotch Bond to seal the pulp chamber following root-canal treatment., Methodology: Root-canal treatment was completed on 100 extracted human mandibular molars. The teeth were divided into five groups of 20 teeth each, one group for each barrier material and one control group without barrier material. Two millimetres of the restorative material was placed on the pulp chamber floor. The teeth were thermocycled and evaluated for microleakage using India ink. Specimens were cleared and measurements made to the maximum point of dye penetration. The mean dye penetration for each group was compared by the Kruskal-Wallis test., Results: All groups showed dye penetration. Coltosol and IRM sealed significantly better than the other groups, preventing the coronal leakage in 84% and 75% of the specimens, respectively. Scotch Bond exhibited the highest leakage (54% of specimens with dye penetration), which did not differ significantly from the positive control group (62% with dye penetration)., Conclusions: None of the materials were able to prevent microleakage in all specimens. Vidrion R and Scotch Bond demonstrated the poorest results when used as barriers to coronal microleakage, whilst IRM and Coltosol were significantly better in preventing microleakage.

Aim: To compare the ability of a single bond adhesive to its preceding multiple step dentin bonding agent in reducing microleakage around class V composite resin in primary teeth., Material and Methods: Twelve children, between 9 and 11 years old, with non-carious primary canines indicated for extraction for orthodontic purposes, were selected for this study. Each child had facial surfaces of his or her upper and/or lower canines prepared for class V cavities. One canine was randomly selected for restoration using the Scotchbond Multi Purpose Plus System (group I) and its antimere for the Single Bond adhesive (group II). Thirty cavities were restored by Z-100 composite. Materials were handled according to the instructions of the manufacturer. All teeth were extracted one month later, immersed in 2% basic fuchsin then sectioned to evaluate dye penetration., Results: No statistically significant difference was found in the degree of microleakage between the two materials., Conclusions: Neither of the two adhesive systems was able to completely prevent leakage of class V restorations. Additional preventive measures should be implemented whenever using composite resin restorations in children.

Aim: The aim of the present study was to evaluate the long-term sealing ability (both apical and coronal) of an epoxy resin root canal sealer (AH26) when used with different gutta-percha obturation techniques., Methodology: Straight single-rooted teeth with mature apices were divided into 10 groups of 75 teeth and one group of 40 control teeth. Root canals were prepared according to the crown-down/step-back technique and using both 2.5% sodium hypochlorite and an EDTA paste. Root canals were obturated using cold lateral condensation, warm vertical condensation and hybrid condensation of gutta-percha; and with Thermafil and Soft-Core obturators. AH26 was used as the sealer in all cases. After root canal filling, each group was divided into five individual groups of 15 teeth. The first group of 15 teeth was kept for 1 day, the second for 1 week, the third for 4 months, the fourth for 6 months and the fifth for 12 months at 37 degrees C in vacutainers in 80% relative humidity. The teeth were immersed in India ink for 90 h, each root was split and sectioned longitudinally, and the maximum extent of leakage was measured using a stereomicroscope at x6 magnification., Results: Leakage occurred whatever filling technique was combined with AH26. The number of teeth with gross leakage increased with time up to 4 months, but did not appear to increase between 6 and 12 months storage. The degree of apical leakage and the number of leaking teeth in the Soft-Core obturator groups was significantly higher than all four other gutta-percha obturation techniques. Up to 4 months the degree of coronal leakage and the number of leaking teeth in the Thermafil groups was significantly higher than the other gutta-percha obturation techniques, except for Soft-Core. In the Soft-Core obturator groups the degree of coronal leakage and the number of leaking teeth was significantly higher than the other gutta-percha obturation techniques, except for Thermafil at all evaluation times., Conclusion: The hybrid gutta-percha condensation technique was superior to the other four obturation techniques in respect of apical leakage. Coronal leakage was significantly greater during the first 4 months for the Thermafil system as compared to the three condensation techniques; coronal leakage was significantly greater at all time periods for the Soft-Core system. There were no significant differences between the Thermafil and the Soft-core system.

Aim: The aim of this study was to determine the quality of cold and warm gutta-percha fillings in oval canals., Methodology: Two groups of mandibular premolars with oval canals were selected after bucco-lingual and mesio-distal radiographs indicated an internal long: short diameter of > or =1.6 at a level 5 mm from the apex. After instrumentation they were obturated, respectively, by cold lateral compaction of gutta-percha cones (cold GP) and vertical compaction of warm gutta-percha (warm GP). Leakage along apical root fillings was measured using a fluid transport model. After the leakage test, horizontal sections were cut 2 and 4 mm from the apex. The area of the canal and gutta-percha in cross-sections was measured using an image analysis program. The quality of root fillings was evaluated by calculating the percentage of gutta-percha-filled canal area (PGP)., Results: No significant difference in leakage was found between the two groups (P = 0.570). The warm GP group produced significantly higher PGPs than the cold GP group 4 mm from the apex only (P = 0.522 at 2 mm: P = 0.000 at 4 mm)., Conclusions: The percentage of gutta-percha-filled canal area using warm GP was greater than that of the cold GP in oval canals.

Aim: The purpose was to present the frequency of periapical healing in first and second/third mandibular molars, after root-end resections sealed with a dentine-bonded resin composite., Methodology: Root-end sealing of resected mandibular molar roots was made with dentine-bonded composite (Gluma-Retroplast) as a cover on the entire slightly hollowed root-end, in an attempt to prevent leakage., Results: Out of the 834 roots recalled between 6 months and 12.5 years postoperatively, 92% showed complete apical healing, 1% uncertain healing and 7% exhibited failure. The healing result of 681 first molar roots was not significantly different (P = 0.21) from that of 153 second/third molar roots, and there was no significant difference in healing between mesial and distal roots (P = 0.32 for first molars, P = 0.86 for second/third molars) or amongst six age groups (P = 0.94). In the patient group: 71-89 years, 36 roots showed an average of 97% with complete healing. Out of 25 failures who were retreated surgically, 80% showed complete healing when examined subsequently., Conclusion: Root-end sealing of mandibular molars with dentine-bonded resin composite is a promising technique giving 92% complete healing in cases examined between 6 months and 12 years postoperatively.

Objectives: To investigate the influence of three Erbium:YAG pulse energies (200 mJ, 240 mJ, and 300 mJ with a 100 mJ dentine finish) on the microleakage of Class V compomer restorations (Compoglass)., Design: In vitro study., Sample and Methods: Sixty-one extracted human premolar teeth were randomly allocated to three groups (according to pulse energy). Each tooth hosted one test cavity prepared with one of the three Er:YAG pulse energies using a pulse repetition rate of 5 Hz and a pulse duration of 250 microseconds, and one control cavity prepared with a conventional diamond bur in a high-speed hand piece. Both cavities were placed at the cervical margin of the tooth and were restored and finished according to the manufacturer's instructions. Each tooth was then stored in 0.12% thymol solution at 37 degrees C for three months, before being thermocycled through water baths between 5 degrees C and 55 degrees C for 240 cycles. Microleakage was assessed using a methylene blue dye penetration technique and was quantified using a score 0 (none) to 4 (to and into the axial wall). The data was analysed using the Kruskal-Wallis and Mann-Whitney U-tests., Results: Leakage was seen in all groups at both the dentine and enamel margins. There were no statistically significant differences in leakage (P < 0.05) at either the enamel or dentine margins, except for the 240 mJ lased enamel margins. This group performed significantly better than the enamel margins prepared with 200 mJ (P = 0.03) and the 300/100 mJ (P = 0.01) laser energies as well as the conventionally prepared enamel margins (P < 0.001)., Conclusion: Cavity preparation with this Erbium:YAG laser did not influence the microleakage of Compoglass restorations adversely. Different pulse energies were required for optimum cavity sealing at the enamel and dentine margins and for different materials.

Aim: This study evaluated the removal of smear layer at the apical stop by pulsed Nd:YAG laser irradiation with or without black ink, and the degree of apical leakage after obturation in vitro., Methodology: Sixty extracted human single-rooted teeth were used in this study. The teeth were instrumented up to a size 40 K-file, and then divided into three groups of 20 teeth each: group 1 was unlased as a control group; group 2 was treated with a laser; group 3 was treated with a laser and black ink. The laser was operated at 2 W and 20 pp for 2 s, and irradiation was performed twice with a 30-s interval. In each group, 10 teeth for the leakage study were obturated and immersed in rhodamine B solution for 48 h at 37 degrees C, and the others were used for evaluation of remaining smear layer. All teeth were bisected longitudinally and observed by stereoscopy or scanning electron microscopy., Results: The smear layer in the laser-treated groups almost melted or evaporated, and was removed significantly compared with the control group (P < 0.05). Leakage was observed in 60% of samples in group 1 and in 20% of samples in group 2. No leakage was observed in group 3, which was significantly different from the control (P < 0.05)., Conclusions: These results suggest that pulsed Nd:YAG laser irradiation with black ink increases the removal of smear layer compared with that without black ink, and reduces apical leakage after obturation significantly.

This in vitro study evaluated the effect of different luting procedures on the proper seating of ceramic inlays and on the marginal seal through microleakage testing. Sixty mesial-, occlusal-, distal- (MOD) cavities were prepared in third molars, and distributed among four groups. In the control group 1, the cavity surface was treated with dentin and enamel bonding agents; ceramic inlays were placed into the cavity and light cured. In group 2, the dentin and enamel bonding agents were cured prior to the placing of the inlays, and following the insertion. In group 3, the inlays were luted without enamel bonding. In group 4, the inlays were cemented using a one-bottle bonding and two times light curing. The groups with only one time light curing at the end of the luting process exhibited the smallest luting space following cementation. The smallest dye penetration values were obtained for the two groups with separate light curing of the dentin bonding agent. Reducing the film thickness of polymerized dentin bonding agents, i.e. by changing the composition of the bonding agents, could facilitate proper seating of ceramic inlays together with a better marginal seal.

Aim: The purpose of this study was to evaluate the sealing ability of two contemporary endodontic obturation and restorative techniques and materials., Methodology: Seventy-nine extracted human single-rooted teeth were distributed randomly in two experimental groups of 36 and 37 specimens (groups 1 and 2, respectively), one group of three positive controls and one of three negative controls. The teeth were radiographed preoperatively, accessed, and instrumented. After smear layer removal, the teeth in group 1 were obturated using the System B and Obtura and were restored coronally with Core Paste using Tenure as a bonding agent. The teeth in group 2 were obturated using the Microseal technique and were restored coronally with amalgam using Panavia 21 as a bonding agent. All teeth in groups 1 and 2 were coated with three layers of nail varnish on all of their surfaces apart from the apical 4.0 mm and the coronal area above the cemento-enamel junction. The positive control teeth were obturated, restored coronally and completely coated with varnish, whereas the negative control teeth were not obturated, restored coronally, nor coated with varnish. The teeth were radiographed postoperatively and retained in saline solution for 10 days. For the next 10 days they were submerged in India ink. Subsequently all teeth were demineralized, dehydrated and rendered transparent. Dye penetration was measured using a stereomicroscope., Results: All materials and techniques provided minimal to zero dye penetration, apart from one specimen in the Core Paste group that showed 4.0 mm of dye penetration. The Wilcoxon rank sum test and t-test showed no statistically significant differences and all materials and techniques tested presented with a high degree of acceptability., Conclusions: It was concluded that these contemporary techniques and materials provide equally good results, but long-term studies are needed for outright inferences to be drawn relative to their clinical performance.

Objective: To improve the quality of resin restorations, studies are necessary not only of the physical properties of materials but also of the cavity geometry. We have evaluated marginal microleakage for two types of photo-curing composite resin applied to cavities with different marginal structures., Sample and Methods: The test materials were 91 extracted upper primary molars. The two composite resins used in this experiment were Liner Bond II (LBII) and Photo Clearfil A (PCA). A class I cavity was created in each tooth; the cavity configuration was a round bevel, a straight bevel and a butt joint. The tooth was then restored with each composite resin. Each tooth was exposed to thermal cycles, followed by immersion in 0.2% basic fuchsin solution. Three sections, through the mesial, central and distal areas of each tooth were taken. The penetration of the dye was examined with a stereoscopic microscope. The sites of observation for examination of microleakage were awarded scores of between 0 and 7., Results: LBII-among the three marginal forms, absence of leakage was observed most frequently in the straight bevel group followed by the round bevel and the butt joint groups, in the mesial and distal sections. In the central section, the straight bevel did not show any scores of 0, 6 or 7. PCA-an absence of leakage in the mesial section occurred most frequently for the round bevel group. However, the absence of leakage in the central and distal sections was most frequent for the straight bevel group. Microleakage of the central section (with scores from 1 to 7) was frequently lower than that for the mesial and distal sections. Scores of 5 and above in the central section were observed only in the butt joint group. The frequency and mean score of leakage were clearly higher in LBII than in PCA, with one significant exception. For both composite resins, the butt joint group showed higher-mean scores of leakage than did either the round or straight bevel group, but for PCA, the mean score of the central section was lower than the other two sections in all groups., Conclusion: Our study shows that beveling does reduce marginal leakage. This leakage was more frequently observed with the use of LBII than with PCA. However, the amount of tooth ground away was greater for the bevel-treated cavity. In considering these features, special care is necessary in selecting the bur for treating a bevelled cavity.