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The aim of the study was to evaluate the effect of preparation depth and intraradicular extension on the marginal and internal adaptation of computer-aided design/computerassisted manufacture (CAD/CAM) endocrown restorations. Standardized preparations were made in resin endodontic tooth models (Nissin Dental), with an intracoronal preparation depth of 2 mm (group H2), with extra 1-(group H3) or 2-mm (group H4) intraradicular extensions in the root canals (n=12). Vita Enamic polymer-infiltrated ceramic-network material endocrowns were fabricated using the CEREC AC CAD/CAM system and were seated on the prepared teeth. Specimens were evaluated by microtomography. Horizontal and vertical tomographic sections were recorded and reconstructed by using the CTSkan software (TView v1.1, Skyscan).The surface/void volume (S/V) in the region of interest was calculated. Marginal gap (MG), absolute marginal discrepancy (MD), and internal marginal gap were measured at various measuring locations and calculated in microscale (μm). Marginal and internal discrepancy data (μm) were analyzed with nonparametric Kruskal-Wallis analysis of variance by ranks with Dunn's post hoc, whereas S/V data were analyzed by one-way analysis of variance and Bonferroni multiple comparisons (α=0.05). Significant differences were found in MG, MD, and internal gap width values between the groups, with H2 showing the lowest values from all groups. S/V calculations presented significant differences between H2 and the other two groups (H3 and H4) tested, with H2 again showing the lowest values. Increasing the intraradicular extension of endocrown restorations increased the marginal and internal gap of endocrown restorations. [ABSTRACT FROM AUTHOR]

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The aim of the study was to evaluate the effect of preparation depth and intraradicular extension on the marginal and internal adaptation of computer-aided design/computer-assisted manufacture (CAD/CAM) endocrown restorations. Standardized preparations were made in resin endodontic tooth models (Nissin Dental), with an intracoronal preparation depth of 2 mm (group H2), with extra 1- (group H3) or 2-mm (group H4) intraradicular extensions in the root canals (n=12). Vita Enamic polymer-infiltrated ceramic-network material endocrowns were fabricated using the CEREC AC CAD/CAM system and were seated on the prepared teeth. Specimens were evaluated by microtomography. Horizontal and vertical tomographic sections were recorded and reconstructed by using the CTSkan software (TView v1.1, Skyscan).The surface/void volume (S/V) in the region of interest was calculated. Marginal gap (MG), absolute marginal discrepancy (MD), and internal marginal gap were measured at various measuring locations and calculated in microscale (μm). Marginal and internal discrepancy data (μm) were analyzed with nonparametric Kruskal-Wallis analysis of variance by ranks with Dunn's post hoc, whereas S/V data were analyzed by one-way analysis of variance and Bonferroni multiple comparisons (α=0.05). Significant differences were found in MG, MD, and internal gap width values between the groups, with H2 showing the lowest values from all groups. S/V calculations presented significant differences between H2 and the other two groups (H3 and H4) tested, with H2 again showing the lowest values. Increasing the intraradicular extension of endocrown restorations increased the marginal and internal gap of endocrown restorations.

Background: The aim of this study was the characterization of mechanical properties of representative types of orthodontic wires employing instrumented indentation testing (IIT) according to ISO 14577., Methods: Segments were cut from ten wires. The first six are made of stainless steel (SS), two are made of Ni-Ti, and the last two are made of titanium molybdenum alloys (TMA). Then, the Martens hardness (HM), the Vickers hardness (HVIT) based on indentation hardness (H IT), the indentation modulus (E IT), the ratio of elastic to total work (η IT), and the traditional Vickers hardness (HV1) were measured by IIT. The results were statistically analyzed by one-way ANOVA followed by Student-Newman-Keuls (SNK) test at a = 0.05. The HVIT and HV1 data were analyzed by paired t test (a = 0.05)., Results: SS wires showed the highest hardness followed by TMA and Ni-Ti alloys. However, all wires showed significantly lower HVIT compared to corresponding HV1, a finding probably appended to elastic recovery around the indentation. E IT for all wires tested was determined much lower than the nominal values of the corresponding alloys due to the implication of residual stress field at the slope of unloading curve. Elastic to total work ratio was ranged from 45.8 to 64.4 % which is higher than that expected for ductile alloys (<30 %)., Conclusions: The products tested illustrated significant differences in their mechanical properties. Although IIT provides reliable data for hardness and elastic index of materials tested, the intense residual stress field developed during the manufacturing process significantly affects the determination of modulus of elasticity.

Objectives: To identify the TiO2 phases of the root surface of commercially available titanium dental implants, subjected to various surface treatments., Methods: The titanium implants studied were: Allfit (ALF), Ice (ICE), IMZ TPS (TPS), Laser Lok (LLK), Prima Connex (PRC), Ospol (OSP), Osseospeed TX (OSS), Osseotite Full (OTF), Replace Select (RPS), SLA (SLA) and Trilobe (TRB). The root parts of the implants (n:2) were analyzed by Raman microspectroscopy employing argon ion laser excitation (514.5nm wavelength) and a 100 μm × 100 μm sampling area at two randomly selected sites., Results: The spectra of OSP and RPS showed the characteristic peaks of anatase, with traces of rutile (RPS). Complex phases composed of anatase, rutile and amorphous TiO2 were identified in ALF, ICE and LLK. Rutile and amorphous TiO2 were found in PRC, OSS, OTF, TPS and TRB, whereas rutile and possibly brookite were traced in SLA. In all implants, except OSP and RPS, peaks assigned to organic impurities (CH2, CH3) and carbonates were recorded. Ti2O3 was identified in OTF, PRC and Al2O3 in TRB., Significance: Great variations in the TiO2 polymorphs were registered among the implant root surfaces tested. Considering the important differences in the biological activity of these polymorphs, it can be concluded that provision of information regarding the TiO2 state on implant surfaces should be a mandatory task for implant manufacturers., (Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.)

Two shades of four resin cements (Calibra, Clearfil Esthetic, Insure, Variolink II), in light- and dual-curing modes, were tested for colour matching with their corresponding try-in pastes, immediately after photopolymerization and after 24-hour dry and dark storage. Colour measurements were performed for 0.8 mm-thick specimens through a 0.8mm-thick ceramic plate. For each resin cement, colour differences (deltaE) were calculated between the two curing modes, and between the corresponding try-in paste, at baseline and after 24h. deltaE>0 values were detected between all resin cements and their try-in pastes, which were brand/shade/curing mode depended. The try-in pastes of the Variolink II system demonstrated the best colour matching (deltaE<2). Try-in pastes of Calibra and Insure, at both curing modes, did not match at an acceptable value, the shade of their corresponding resin cements (deltaE>3.3). Calibra presented the highest colour differences. deltaE values of the Clearfil Esthetic system immediately after photo-activation ranged between 2 and 3 units. A ceramic restoration may fail aesthetically as a result of not acceptable colour match (deltaE>3.3) between the shade of certain resin cements and their relevant try-in pastes.

Purpose: To evaluate the efficacy of the DenShield desensitizing system, based on calcium sodium phosphosilicate, in the hypersensitivity reduction for a 6-month period in periodontitis patients previously subjected to periodontal treatment and to compare the combination of the in-office paste and at-home dentifrice use to the at-home dentifrice use alone., Methods: A total of 248 teeth (eight teeth in each subject) in 31 periodontitis patients (mean age 48 +/- 8 years) previously subjected to periodontal treatment were studied. 193 (77.8%) teeth had been treated with phase I periodontal treatment alone (non-surgical treatment) and 55 (22.2%) had been additionally subjected to periodontal surgery. Periodontal clinical parameters were recorded for each subject. Hypersensitivity was assessed by tactile and air-blast stimuli. The hypersensitive teeth of each of two quadrants in each subject were randomly assigned with split-mouth design to in-office application of DenShield Starter paste (four teeth) or placebo (distilled water) (four teeth). After the in-office application each patient used the DenShield dentifrices (Builder and Saver) for 6 months. The final evaluation was at 6 months., Results: The prevalence and the degree of baseline hypersensitivity was significantly higher for the surgically than the non-surgically-treated teeth (83.6% versus 68.4%) and it was greater in teeth with attachment loss. The dentin hypersensitivity observed after periodontal treatment was significantly reduced in periodontitis patients who used the DenShield system for 6 months. There was no difference in hypersensitivity reduction between the additional in-office application of the DenShield and the at-home use of the DenShield dentifrices alone.

Objectives: The purpose of this study was to investigate the color change in two "self-etch" and one "etch and rinse" adhesive under dark/water and photoaging conditions and to evaluate the influence of these changes on the color stability of resin composite restorative systems., Methods: The adhesives were: One-Up Bond F (OB/Tokuyama), Adper Prompt L-Pop (PL/3M Espe) and Optibond Solo Plus (OS/Kerr). 10 sample disks of each material were prepared (OB(1), LP(1), OS(1)). Additionally, 30 sample discs of TPH Spectrum (Caulk/Dentsply) resin composite were prepared and bonded with the three adhesives tested (OB(2), LP(2), OS(2) groups) to freshly cut dentin discs. 30 days of storage in deionised water (37+/-1 degrees C) in dark conditions was followed by exposure of all samples to UV light photoaging. A colorimetric evaluation (CIEL*a*b* system) was performed immediate after sample photopolymization (baseline), at 7 and 30 days of dark/water storage and after the 360h of UV aging. Color changes (DeltaE*) were calculated between baseline and subsequent measurements. The results were analyzed by independent two-way Anova and Sheffe's statistical tests (a=0.05)., Results: All the adhesives evaluated exhibited significant color changes even after early aging time into water. One-Up Bond F presented the highest color alterations under both experimental conditions and Optibond Solo Plus the lowest. The adhesives were proved able to influence the color stability of a resin composite, which is bonded to a dentin substrate. One-Up Bond F induced the strongest effect on color change of the resin composite while no differences were clarified between Adper Prompt L-Pop and Optibond Solo Plus., Conclusion: Significant color changes were determined under water and photoaging conditions for the "self-etch" and "etch and rinse" adhesives evaluated and the resin composite combined with these agents.

Purpose: To evaluate the phase separation, extent of dentin demineralization, and curing efficiency of one-step self-etching adhesives placed on dentin and on inert substrate., Materials and Methods: The adhesives tested were G-Bond (GB), iBond (IB) and Clearfil S3 Bond (SB). Two groups (2 x 3) of dentin and inert (gold) specimens were prepared for each product. The films formed on inert surfaces were subjected to mild (1st group) or strong air drying (2nd group) and examined with near- and mid-FTIR microspectroscopy. On dentin (1st group), the extent of demineralization (% DM) was evaluated before and after adhesive treatment plus rinsing with water and acetone by mid-FTIR microspectroscopy. The films formed after strong air drying (2nd group) and 20 s of light curing were rinsed with acetone, and the degree of cure (% DC) was measured by micro-multiple internal reflection FTIR spectroscopy. ANOVA was used to assess the statistically significant differences in % DM and % DC (alpha = 0.05)., Results: In GB and IB, mild air drying produced more water droplets and monomer separation than strong air drying. SB demonstrated the least separation. IB induced the highest % DM. All the adhesives demonstrated the greatest % DC on dentin. On both substrates SB showed the highest % DC values., Conclusion: Phase separation including water and/or monomers was found in all the adhesives. The extent of dentin demineralization and degree of cure varied among the products tested. The degree of cure was higher on dentin than on the inert substrate.

The colour stability of the surface and in-depth (2 mm) layer of two resin composites, a laboratory second-generation resin composite and a compomer were evaluated after 24 and 360 hours of water aging under dark and UV light conditions. The influence of various polymerization techniques on color changes was also evaluated. Color differences (deltaE*) showed higher color changes under UV light exposure than under dark storage, both at 24- and 360-hour evaluations. Color changes were statistically higher at the 360-hour assessment, in both conditions of maintenance. Compomer was the least color stable of the materials tested. Additional polymerization significantly decreased the colour change of both composite resins.

This study compared the pulp responses to two light-cured glass ionomer liners with a chemically set glass ionomer lining cement and zinc oxide-eugenol. Deep Class V cavities were prepared at high-speed with carbide burs under a water coolant in 96 teeth of three young adult beagle dogs. The smear layer was left intact according to the manufacturers' recommendations. The cavities in each quadrant were lined with either Vitrebond light-cured glass ionomer liner, X-R Ionomer light-cured liner, GC lining cement or ZOE which served as a control. All cavities were restored with Silux Plus resin composite. The ZOE liner was covered with a varnish prior to the resin composite placement. The animals were terminated at 1, 4 and 12 weeks. Jaws were excised, fixed in 10% formalin and decalcified in 5% formic acid. Teeth were sectioned at 7 microns, and stained with hematoxylin and eosin. Selected slides were stained with the Brown and Hopps method for histologic demonstration of bacteria. The microscopic findings indicated that pulpal reactions to the two light-cured glass ionomer liners were minimal and comparable to those elicited by the chemically-cured glass ionomer lining cement and ZOE. Bacteria were observed in nine specimens but only one of these revealed a moderate pulp reaction.