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Safety and effectiveness of maxillary early loaded titanium implants with a novel nanostructured calcium-incorporated surface (Xpeed): 1-year results from a pilot multicenter randomised controlled trial.
Esposito, M, Grusovin, MG, Pellegrino, G, Soardi, E, Felice, P
European journal of oral implantology. 2012;(3):241-9
Abstract
PURPOSE To evaluate clinical safety and effectiveness of a novel calcium-incorporated titanium implant (Xpeed, MegaGen Implant Co. Limited, Gyeongbuk, South Korea). MATERIALS AND METHODS Sixty patients were randomised to receive either 1 to 6 calcium-incorporated or control titanium implants in the maxilla according to a parallel group design at 2 different centres. Implants were submerged and exposed at 3 different endpoints in equal groups of 20 patients each at 12, 10 and 8 weeks, respectively. Within 2 weeks, implants were functionally loaded with provisional or definitive prostheses. Outcome measures were prosthesis failures, implant failures, any complications and peri-implant marginal bone level changes. RESULTS Thirty patients received 45 calcium-incorporated implants and 30 patients received 42 control titanium implants. One year after loading, no drop-outs and no prosthesis or implant failures occurred. There were no statistically significant differences between groups for complications (P = 0.61; difference in proportions = -0.27; 95% CI -0.71 to 0.18) and mean marginal bone level changes (P = 0.64; mean difference -0.04 mm; 95% CI -0.22 to 0.13). CONCLUSIONS Nanostructured calcium-incorporated titanium implants seem to be at least as effective and safe as conventional titanium implants.
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Remineralization of early caries by a nano-hydroxyapatite dentifrice.
Najibfard, K, Ramalingam, K, Chedjieu, I, Amaechi, BT
The Journal of clinical dentistry. 2011;(5):139-43
Abstract
OBJECTIVE The purpose of this randomized, double-blind, crossover, in situ study was to evaluate the efficacy of nano-hydroxyapatite (nHAP) dentifrices on caries remineralization and demineralization inhibition. METHODS Three demineralized enamel blocks (A,B,C) and one healthy block (D), cut from each of 30 molars, were exposed respectively to dentifrices of A) 5% nHAP, B) 10% nHAP, C) 1100 ppm fluoride, and D) 10% nHAP via an intra-oral appliance worn by 30 adults in this four-phase study lasting 28 days per phase. Baseline and post-test mineral loss (delta Z) and lesion depth (LD) were quantified using microradiography. RESULTS Pair-wise comparison (baseline versus test) demonstrated significant (p < 0.001) reductions in delta Z and LD in A, B, and C. ANOVA showed no significant differences among the three products in percent mineral gain. No demineralization occurred in the sound enamel specimens exposed intra-orally while using 10% nHAP. CONCLUSION nHAP dentifrice caused remineralization comparable to a fluoride dentifrice, and inhibited caries development, thus suggesting that an nHAP dentifrice can be an effective alternative to fluoride toothpaste.
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Three-body wear of resin denture teeth with and without nanofillers.
Stober, T, Henninger, M, Schmitter, M, Pritsch, M, Rammelsberg, P
The Journal of prosthetic dentistry. 2010;(2):108-17
Abstract
STATEMENT OF PROBLEM The wear behavior of newly developed denture teeth with nanofillers may be different from teeth with other chemical formulations. PURPOSE The purpose of this study was to examine the 3-body wear resistance of 11 different commercially available resin denture teeth. MATERIAL AND METHODS The materials tested were conventional (SR Orthotyp PE, Orthognath) and cross-linked acrylic resin teeth without inorganic fillers (Premium 8, SR Postaris DCL, Trubyte Portrait, Artiplus), composite resin teeth with inorganic fillers (SR Orthosit PE, Vitapan), and composite resin teeth (experimental materials) with inorganic nanofillers (NC Veracia Posterior, e-Ha, Mondial). Human enamel and a ceramic denture tooth (Lumin Vacuum) were used as reference materials. The 3-body wear test was performed in a wear machine developed by the Academic Center for Dentistry Amsterdam (ACTA), with millet suspension acting as an abrasive medium (n=10, test load: 15 N, slip rate: 20%, number of cycles: 100,000). Wear was determined with the aid of a profilometer. Data were analyzed with the Kruskal-Wallis test and Mann-Whitney U test using the closed testing approach (significance level for familywise error rate, alpha=.05). RESULTS None of the acrylic and composite resin materials tested in this study demonstrated the 3-body wear resistance of ceramic teeth or human enamel. Teeth with inorganic fillers demonstrated significantly lower wear values than conventional or cross-linked acrylic resin teeth without fillers. Composite resin teeth with traditional fillers showed significantly lower wear than composite resin teeth with nanofillers. CONCLUSIONS Denture teeth with and without inorganic fillers differed significantly with regard to the degree of wear generated in the ACTA wear simulator. The incorporation of nanofillers did not improve the wear resistance compared to teeth with traditional fillers.
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Shear bond strength of three different nano-restorative materials to dentin.
Korkmaz, Y, Gurgan, S, Firat, E, Nathanson, D
Operative dentistry. 2010;(1):50-7
Abstract
OBJECTIVES To evaluate the shear bond strength (SBS) of a nano-composite, a flowable nano-composite and a nano glass ionomer to dentin in vitro. MATERIALS AND METHODS Sixty human molars were ground flat, exposing the dentin surfaces, and they were randomly divided into five groups according to the restorative materials and adhesive systems used (n = 12/group). The restoratives were applied to all dentin surfaces according to the manufacturer's instructions, using a special jig (Ultradent) in the following manner: Group 1: a nano-composite (NC) (Filtek Supreme XT-3M ESPE) was applied with a two-step self-etch adhesive (SE) (Adper SE Plus-3M ESPE); Group 2: NC was applied with an etch&rinse adhesive (SB) (Adper Single Bond 2-3M ESPE); Group 3: a flowable nano-composite (FNC, Filtek Supreme XT Flow-3M ESPE) was applied with SE; Group 4: FNC was applied with SB and Group 5: a nanofilled resin-modified glass ionomer (Ketac N100-3M ESPE) was applied with Ketac Nano Primer (3M ESPE). The bonded specimens were stored in distilled water (37 degrees C, 24 hours) and tested for SBS in a universal testing machine (1 mm/minute). Two specimens from each group were subjected to SEM evaluations of the adhesive interfaces. Failure modes were determined using a stereomicroscope. The mean SBS values were calculated and the data were analyzed with the Kruskal Wallis and Mann-Whitney-U tests (p < 0.05). RESULTS Mean SBS values (MPa) for the groups were 13.64; 7.83; 11.20; 4.12 and 0.64 for Groups 1, 2, 3, 4 and 5, respectively. Group 1 exhibited a significantly higher value than all the other groups; whereas, Group 5 had the lowest value (p < 0.05). The SE adhesive yielded higher bond values than the SB adhesive with NC and FNC restorative materials. Failure modes in all the groups were primarily adhesive. CONCLUSION The results demonstrate the capacity of the current two-step self-etch adhesive to outperform the etch&rinse adhesive in conjunction with the two nano-restoratives tested.
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Nano-emulsion formulation using spontaneous emulsification: solvent, oil and surfactant optimisation.
Bouchemal, K, Briançon, S, Perrier, E, Fessi, H
International journal of pharmaceutics. 2004;(1-2):241-51
Abstract
Nano-emulsions consist of fine oil-in-water dispersions, having droplets covering the size range of 100-600 nm. In the present work, nano-emulsions were prepared using the spontaneous emulsification mechanism which occurs when an organic phase and an aqueous phase are mixed. The organic phase is an homogeneous solution of oil, lipophilic surfactant and water-miscible solvent, the aqueous phase consists on hydrophilic surfactant and water. An experimental study of nano-emulsion process optimisation based on the required size distribution was performed in relation with the type of oil, surfactant and the water-miscible solvent. The results showed that the composition of the initial organic phase was of great importance for the spontaneous emulsification process, and so, for the physico-chemical properties of the obtained emulsions. First, oil viscosity and HLB surfactants were changed, alpha-tocopherol, the most viscous oil, gave the smallest droplets size (171 +/- 2 nm), HLB required for the resulting oil-in-water emulsion was superior to 8. Second, the effect of water-solvent miscibility on the emulsification process was studied by decreasing acetone proportion in the organic phase. The solvent-acetone proportion leading to a fine nano-emulsion was fixed at 15/85% (v/v) with EtAc-acetone and 30/70% (v/v) with MEK-acetone mixture. To strength the choice of solvents, physical characteristics were compared, in particular, the auto-inflammation temperature and the flash point. This phase of emulsion optimisation represents an important step in the process of polymeric nanocapsules preparation using nanoprecipitation or interfacial polycondensation combined with spontaneous emulsification technique.