The current review aimed to inform reconstructive surgeons of how combinations of various mesenchymal stem cells, scaffolds, and growth factors enhance bone regeneration. The highest bone regeneration has been achieved when combination of all three elements, given scaffolds, mesenchymal stem cells, and growth factors, were used.
Aim:The purpose of this in vitro study was to investigate the effect of interimplant distance and cyclic loading on the retention of two locator attachment systems.
Materials and methods:A total of 72 acrylic resin blocks were fabricated and divided into six groups of six pairs each. Locators of DIO and 3i implant systems were positioned on analogs in three different interimplant distances (19, 23, and 29 mm). The blocks were attached to a universal testing machine, and 1,440 dislodging cycles by the force of 136 N were applied. After 0, 120, 360, 720, and 1,440 cycles, the retention was recorded. Three-way analysis of variance (ANOVA) was used to test for differences in retention between the various combinations of the locator, interimplant distance, and cyclic loadings.
Results:Interimplant distance was significantly associated with retention, independent of the locator system used, and dislodgement force cycles. Mean retention was significantly higher under the 3i system relative to the DIO system (p < 0.0001). This association varied with both interimplant distance (p > 0.0001) and dislodgement force (p < 0.0001) as well as across the various combinations of distance and cycle (p < 0.0001).
Conclusion:Interimplant distances could affect the initial retention of locator attachments. There was little difference in retention between distances of 23 and 29 mm across all cycles when both locator systems were combined. Distance of 23 mm was associated with superior retention in the DIO system. With regard to the speed of retention decrease, the 23 mm distance was associated with better performance.Clinical significance: Interimplant distance could play a significant role in overdenture retention with locator attachments.
The effects of adding Al2O3 nanoparticles on the microstructure, tribological, magnetic, and corrosion properties of CuFe-Al2O3 nanocomposites were investigated in this work. The mixture of Cu-25 wt.% Fe powder with 5 vol.% Al2O3 was mechanically milled. X-ray diffraction results revealed that after 60 h of mechanical alloying, CuFe solid solution was formed. Magnetic hysteresis loops of the mechanically alloyed powders were extracted at room temperature. The morphology and elemental analysis of the sintered specimens were studied by field emission scanning electron microscope (SEM). It was observed that uniform distribution and embedding of Al2O3 nanoparticles in the CuFe alloy matrix in nanocomposites were achieved, which exhibited excellent performances. Tribological properties were evaluated through a pin-on-disk wear test, and it was found that by the addition of Al2O3 nanoparticles to CuFe alloy, the weight loss rate was reduced by 30%. The existence of Al2O3 nanoparticles in the matrix of CuFe alloy causes the wear mechanism change from adhesive to abrasive, which means a considerable wear resistance was obtained in nanocomposites. The corrosion properties of the sintered samples in a solution of 3.5% NaCl were studied by potentiodynamic polarization. With the addition of Al2O3 nanoparticles, the corrosion rate of the alloy was reduced by 75%.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.