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To three-dimensionally evaluate the interfacial gap of bulk-fill resin composites applied in deep Class-I restorations with different layering techniques and curing modes.Ninety-six (n = 96) samples were prepared with standardized deep Class-I cavities and adhesive procedures. Four materials were tested: SDR (SDR), SonicFill2 (SF), Admira Fusion X-Tra (AFXT), Filtek Supreme XTE (FS). Four subgroups (n = 6) were created according to layering and curing techniques: 2+2mm increments with soft start curing (SG1), 2+2 mm with conventional curing (SG2), a 4-mm increment with soft start curing (SG3), a 4-mm increment with conventional curing (SG4). All samples underwent micro-CT scans; afterwards, voids surrounding the restorations automatically underwent a thresholding procedure (Mimics, Materialise; Geomagic Studio 12, 3D Systems) to analyze the 3D interfacial gap. Statistical analysis was performed using three-way ANOVA with Tukey's test (significance p0.05).Statistically significant differences were reported between materials, layering techniques and their interaction. No statistically significant differences were reported for polymerisation mode. Bulk-fill materials showed average interfacial gap volumes ranging from 0.031 mm3 to 0.200 mm3, while FS showed volumes ranging from 0.416 mm3 to 1200 mm3.All bulk-fill materials performed statistically significantly better than did FS (p0.05), with no statistically significant differences between them. Curing mode did not influence interfacial gap volume in any group (p0.05), while bulk-filling vs layering influenced the volume of interfacial gaps only in the FS group, which performied better when incrementally applied. Regarding gap localisation, the floor of the cavity was the area with the highest likelihood of gaps in all samples.

Purpose: To evaluate interfacial gap and fracture resistance of endodontically treated maxillary premolars, restored with different glass-fiber reinforced materials. Materials and Methods: Eighty-four extracted intact premolars were endodontically treated and MOD cavities prepared. Specimens were divided into 7 groups (n = 12 for each) as follows: sound teeth (G1); no restoration (G2); direct composite restoration with fiber-reinforced composite (everX Posterior GC) (G3); direct composite restoration (Filtek Supreme XTE, 3M Oral Care; "FSXTE") (G4); a horizontal layer of high-viscosity flowable composite (G-aenial Flow, GC) was placed on the pulp chamber floor, 10 mm x 3 mm glass fibers (everStick NET, GC) were inserted into the cavity (G5); same procedure as in group 5 except the direct restoration was made incrementally with FSXTE (3M Oral Care) (G6); composite overlays were placed (G7). Specimens were scanned with micro-CT to evaluate 3D interfacial gaps before and after chewing simulation using Mimics software to calculate voids between restoration and tooth (dentin and enamel). These data (in mm3) were collected for statistical analysis. Thereafter, specimens were loaded to fracture using a universal testing machine. Maximum breaking loads were recorded in Newton (N). The data obtained were analyzed using two-way ANOVA and post-hoc Tukey's test (p < 0.05). Results: ANOVA showed that horizontal glass-fiber insertions statistically significantly reduced interfacial gaps after chewing simulation. No differences in fracture resistance were found between Filtek Supreme XTE and everX Posterior; moreover, glass-fiber insertion did not significantly improve fracture resistance in either case. Composite overlays achieved significantly better fracture toughness than did direct restorations. Conclusions: For the direct restoration of endodontically treated premolars, the insertion of glass fibers into direct composite restorations was unable to guarantee a significant increase in the fracture resistance or a significant change in the fracture pattern. However, it significantly reduced interfacial gap volume after cycling fatigue.

Aim: To compare the quality of the tridimensional (3D) filling and the presence of radiographic translucencies after root canal obturation with three different techniques: warm vertical condensation, carrier-based and single cone with bioceramic sealer. Methodology: Thirty single-rooted human teeth extracted for periodontal reasons were selected. Glide path was performed with ProGlider and shaping with ProTaper Next (PTN) X1, X2 and X3 up to working length (WL). The specimens were randomly divided into three groups (N=10) for the final 3D filling step: Buchanan's continuous wave of condensation (Group 1, G1), Thermafil® (Group 2, G2) or TotalFill® BC Points™ combined with TotalFill® BC Sealer (Group 3, G3). Micro-CT scans were performed after the obturation step and the slices were 3D reconstructed with standardized parameters. Afterwards, the filled area and the associated radiographic translucencies were computer- isolated, and their volumes were calculated. The statistical analysis was performed using one-way ANOVA and the post-hoc Student- Newmann-Keuls (P

Purpose: The management of complicated crown-root fractures is challenging for endodontic restoration. The present case describes a patient who sustained trauma to the maxillary right central incisor. Materials and Methods: Clinical and radiographic examination showed a complicated crown-root fracture and incomplete root development with periapical radiolucency and inadequate endodontic treatment with overfilling. Orthograde retreatment with MTA apical closure combined with a microsurgical approach to remove of extruded material was performed. Coronal sealing was accomplished with a direct adhesive restoration and marginal relocation. Results: A 5-year follow-up showed complete healing of the periapical lesion and correct preservation of function and esthetic parameters. Conclusion: A modern minimally invasive treatment protocol allows the maximum conservation of residual dental tissues.

Aim: Apical periodontitis (AP) is correlated with a higher risk of developing cardiovascular disease (CVD). No data currently exist to suggest that endothelial dysfunction (ED) improves after endodontic treatment in patients who have AP, despite a link between chronic AP and ED. This study was designed to investigate the expression of early ED markers in young adults with chronic AP, before and after root canal treatment. Methodology: 41 subjects (20 controls and 21 patients with AP) were examined at enrolment. Patients with AP were also assessed 2 and 12 months after treatment. ENDO-PAT was used to measure endothelial flow reserve (EFR) and ELISAs were used to assess plasma levels of interleukin (IL)-1, IL-6 and TNF-alpha, vasoconstrictor ED endothelin (ET)-1, the circulating endothelial adhesion markers intercellular adhesion molecule-1 (ICAM)-1/ CD54 and soluble vascular cellular adhesion molecule-1 (sVCAM)-1/CD106, soluble CD14, and the endothelial leukocyte adhesion molecule E-selectin. Results: Baseline serum levels of ET-1, ICAM-1, E-selectin, IL-1, and sCD14 were elevated in patients with AP compared to the control group. There was no macroscopic evidence of reduced EFR in either group. Treatment for AP was associated with reduced inflammation and improved early ED, indicated by a lowering of IL-1, sCD14, ET-1, ICAM-1/ CD54 and E-selectin levels to resemble those of control subjects. Conclusions: Early vascular ED may be driven by AP but is reversible with effective endodontic treatment.

Purpose: To evaluate the immediate and aged bond strength and interfacial nanolaekage of different adhesives and protocols on dental elements prepared with diamond burs and Er:YAG laser. Materials and Methods: Forty molar crowns were flattened and a standardized smear layer was created. Teeth were divided into two main groups according to the dentin cutting technique: 1. Er:YAG laser for 30 s at 30 Hz repetition rate, 250 mJ energy per pulse, and water spray irrigation set at level 8; and 2. diamond bur. Each group was then divided into subgroups according to the adhesive protocol: SG1: dentin etching for 15 s followed by universal adhesive application (All Bond Universal, Bisco); SG2: universal adhesive application (All Bond Universal); SG3: two-step self-etch adhesive application (Clearfil SE Bond 2, Kuraray Noritake); SG4: etching followed by 3-step etch-and-rinse adhesive application (Optibond FL, Kerr). After curing the adhesives, resin composite buildups of 4 mm were made and specimens were sectioned to obtain 1-mm-thick sticks in accordance with the μTBS test technique. Sticks were stressed to failure at baseline and after 6 months of storage in artificial saliva. Three teeth per group were prepared for nanoleakage interfacial analyses. Data were statistically analyzed with three-way ANOVA and Tukey's post-hoc test (p < 0.05). Results: A significant difference in bond strengths was found for treatment, aging, and adhesive protocol. Nanoleak age analysis showed higher marginal infiltration in Er:YAG-treated groups both at baseline and after aging. Conclusions: Surfaces prepared with diamond burs presented higher bond strengths than did those prepared with Er:YAG laser. Adhesive protocols and aging could influence the adhesive-dentin interface. Further studies are necessary to validate the results obtained.

Introduction: The aim of this micro-CT study was to analyze the geometrical shaping outcomes after instrumentation with rotary and reciprocating glide path and shaping systems. Materials and Methods: The mesio-buccal canals of thirty extracted maxillary first permanent molars were randomized into two groups (n=15): rotary system ProGlider and ProTaper Next X1, X2 (PG-PTN) was compared with reciprocating system WaveOne Gold Glider and WaveOne Gold Primary (WOGG-WOG). Irrigation was performed with EDTA 10% and NaOCl 5%. Specimens were micro-CT scanned before instrumentation and after glide path and shaping. The measured parameters were the increase in canal volume and surface area, the centroid shift and the canal geometry variation through RDR and RA. These parameters were measured in the apical and coronal levels and at the point of maximum curvature. One-way ANOVA and post hoc Turkey-Kramer tests were used to describe the impact of the instrumentation on the selected parameters (P

To evaluate the in vitro efficacy of surface coating sealer (SCS) in reducing the amount of water absorption and stain formation in resin composites.To evaluate the amount of water sorption, 40 stainless steel round molds (n=10 per composite) were filled with Filtek Supreme XTE; Venus Diamond; Clearfil Majesty ES-2; Gradia Direct Anterior. Groups were further divided into two subgroups (n=5) according to the presence/absence of SCS (Easy Glaze). Their masses were measured at baseline and reweighed at 1, 4, 12, and 20 weeks. For staining evaluation, 48 resin composite discs, 2 mm-thick, were obtained with the same composites and SCS was applied on a single surface of each sample. After baseline color assessment, samples were immersed in vials containing 5 mL of six different staining solutions. Color evaluation was performed again after 1, 4, 12, and 20 weeks. Three-way ANOVA was performed to evaluate differences in weight gain and color changes (P0.05).A significant protective action of SCS (P0.001), but not of the composites (P= 0.366) was found. Differences in weight and color change were not influenced by the resin composite, but only by the presence of the coating on the surface of the samples. SCS are well-established materials for polishing and protecting composite restorations from water sorption and color changes. Different staining solutions can still produce different effects on resin composite.Surface coating sealers are able to reduce water uptake and discoloration from resin composites, thus leading to less degradation of composite restorations over time.

Purpose: To evaluate the influence of a three-step etch-and-rinse versus a two-step self-etch adhesive system on immediate post-operative sensitivity. Methods: In total, 204 subjects with one posterior tooth affected by a primary carious lesion were recruited. The subjects were randomly divided into two groups, based on the two multi-step adhesive systems used: Group A (All Bond 3) and Group B (Clearfil Protect Bond). The same skilled operator carried out the restorations using a nano-hybrid composite (Venus Diamond) in oblique stratification. Each increment was light-cured for 20 seconds with a LED lamp (Translux Power Blue). Subjects received a three-level thermal sensitivity questionnaire for post-operative sensitivity ratings. The evaluations were recorded daily for 7 days. Scores were analyzed using the McNemar test and postoperative trends were analyzed with the Friedman test (P< 0.05). All (100%) enrolled subjects completed the follow-up visits. There was no statistically significant difference between the two groups in post-operative sensitivity trends. In both groups, increased post-operative sensitivity was found at Dl, which then decreased significantly during the observation period. Results: The results of this in vivo study showed that both of the tested adhesives, etch-andrinse or self-etch, provided effective dentin sealing, preventing subjects from experiencing post-operative sensitivity in the treatment of medium-depth cavities.

This in vitro study investigated the depth of cure of a microhybrid composite resin when cured with reduced times of exposure to three commercially available curing lights. Different sample thicknesses (1, 2, and 3 mm) were light cured in high intensity polymerization mode (2,400 mW/cm² for 5, 10, 15, and 20 seconds; 1,100 mW/cm² for 10, 20, 30, and 40 seconds; and 1,100 mW/cm² for 10, 20, 30, and 40 seconds, respectively). The degree of conversion (%) at the bottom of each sample was measured by Attenuated Total Reflection Fourier Transform Infrared (ATR F-TIR) analysis after each polymerization step. Data were analyzed by ANOVA for repeated measures, showing the degree of conversion was not influenced by the curing light employed (P = .622) but was significantly influenced by the thickness of composite resin (P.05). Variations in the degree of conversion vs the shorter irradiation time permitted (T1) were not significant among different lamps but were significant among different thicknesses. The depth of cure of microhybrid composite resin appears not to be influenced by the curing light employed. Increased irradiation time significantly increases the degree of conversion. Thickness strongly influences depth of cure.

The mechanisms of the Er3+ photoluminescence enhancement induced by ultrasmall Au nanoclusters (made by less than 20 atoms) incorporated by low-fluence ion implantation into Er-doped silica are discussed. We show that the energy-transfer process from moleculelike Au nanoclusters to the rare-earth ions critically depends on the evolution of the early stages of the Au metal clustering process starting from dispersed or oxidized atoms up to the formation of metal nanometric clusters. This feature has been investigated in detail combining extended x-ray-absorption fine-structure and photoluminescence spectroscopies and using different annealing atmospheres (neutral or reducing) in order to better evidence the chemical with respect to the thermal effect on Au nucleation and growth. We experimentally showed that the enhancement mechanism is improved when the optically active Er ions are coupled to Au clusters composed by 5-10 atoms and it remarkably decreases when the Au cluster size is above 20-30 atoms.