Search results for "Recession"
showing 10 items of 250 documents
Efficacy of a bioactive alloplast, in the treatment of human periodontal osseous defects-a clinical study.
2010
Presently, bone replacement grafts are one of the modalities of therapy for which there is histologic evidence of regeneration coronal to the base of the previous osseous defect. Bioactive glasses are used extensively in medicine and dentistry. This study evaluated the additional efficacy of a bioactive alloplast, PerioGlas, in comparison with open flap debridement only. 8 systemically healthy volunteers were chosen, each having 2 collateral sites with ?6 mm clinical probing depth and radiographic evidence of an intrabony defect. Randomly, one defect was treated with open flap debridement plus bioactive glass (test) and the other with open flap debridement alone (control). At baseline, 3, 6…
Clinical evaluation of an Er:YAG laser combined with scaling and root planing for non-surgical periodontal treatment
2003
Objectifs: le but de cette etude clinique controlee etait de comparer les traitements de maladie parodontale avancee par une association de laser Er:YAG (KEY II®, KaVo, Germany) et de detartrage et surfacage radiculaire manuels (SRP) avec le laser seul. Materiel & Methodes: 20 patients sains presentant des destructions parodontales moderees a avancees furent traites au hasard en bouche divisee par une association de laser Er:YAG et de detartrage et surfacage radiculaire manuels (SRP) (test) et le laser seul (controle). L'energie utilisee en reglage pour le laser etait de 160 mJ/pulsation a un taux de repetition de 10 Hz. Prealablement au traitement, et 3, 6 etl2 mois apres, les parametres s…
Subepithelial connective tissue graft with or without enamel matrix derivative for the treatment of Miller class I and II gingival recessions: a cont…
2012
Background The aim of this study was to evaluate whether the combination of enamel matrix derivative (EMD) with subepithelial connective tissue graft (SCTG) plus coronally advanced flap (CAF) would improve the treatment outcomes of Miller class I and II gingival recessions when compared with the same technique (SCTG plus CAF) alone. Methods The study was designed as a randomized, parallel, controlled, double-blinded clinical trial. Forty-two patients were randomly assigned in the test group (SCTG plus EMD) and in the control group (SCTG). Patients had at least one gingival recession ≥ 2 mm. The clinical parameters were evaluated at baseline and at 14 d, 1, 3, 6 and 12 mo follow-up time poin…
Did the Finnish depression of the early 1990s have a silver lining? : The effect of unemployment on long-term physical activity
2022
This paper studies the impact of long-term unemployment on physical activity. We examined the effects 6 and 15 years following a severe business cycle downturn in Finland over the period 1991–1994. The study sample comprised residents of Northern Finland. The unemployed individuals were 23–26 years old during the downturn. Physical activity, measured by MET minutes and meeting WHO guidelines, was higher 15 years later among those people who experienced the longest periods of unemployment in 1991–1994. Physical activity was somewhat lower among people with relatively shorter periods of unemployment. peerReviewed
Gravity Probe Spin: Prospects for measuring general-relativistic precession of intrinsic spin using a ferromagnetic gyroscope
2020
An experimental test at the intersection of quantum physics and general relativity is proposed: measurement of relativistic frame dragging and geodetic precession using intrinsic spin of electrons. The behavior of intrinsic spin in spacetime dragged and warped by a massive rotating body is an experimentally open question, hence the results of such a measurement could have important theoretical consequences. Such a measurement is possible by using mm-scale ferromagnetic gyroscopes in orbit around the Earth. Under conditions where the rotational angular momentum of a ferromagnet is sufficiently small, a ferromagnet's angular momentum is dominated by atomic electron spins and is predicted to e…
A Precessing Ferromagnetic Needle Magnetometer
2016
A ferromagnetic needle is predicted to precess about the magnetic field axis at a Larmor frequency $\Omega$ under conditions where its intrinsic spin dominates over its rotational angular momentum, $N\hbar \gg I\Omega$ ($I$ is the moment of inertia of the needle about the precession axis and $N$ is the number of polarized spins in the needle). In this regime the needle behaves as a gyroscope with spin $N\hbar$ maintained along the easy axis of the needle by the crystalline and shape anisotropy. A precessing ferromagnetic needle is a correlated system of $N$ spins which can be used to measure magnetic fields for long times. In principle, by taking advantage of rapid averaging of quantum unce…
Ferromagnetic gyroscopes for tests of fundamental physics
2020
A ferromagnetic gyroscope (FG) is a ferromagnet whose angular momentum is dominated by electron spin polarization and that will precess under the action of an external torque, such as that due to a magnetic field. Here we model and analyze FG dynamics and sensitivity, focusing on practical schemes for experimental realization. In the case of a freely floating FG, we model the transition from dynamics dominated by libration in relatively high externally applied magnetic fields, to those dominated by precession at relatively low applied fields. Measurement of the libration frequency enables in situ measurement of the magnetic field and a technique to reduce the field below the threshold for w…
Astrochronology of the Valanginian stage from GSSP candidates and hypostratotype.
2013
Valanginian; Astrochronology; Gamma-ray spectrometry; Weissert event; Paraná-Etendeka; International audience; The Valanginian Stage currently displays no radiometric age, which severely hampers palaeoceanographic reconstructions for this time interval. An astrochronology of the Valanginian Stage using the stable 405-kyr eccentricity cycle was performed on biostratigraphically well-calibrated standard sections from the Vocontian Basin (southeastern France). High-resolution gamma-ray spectrometry signals were obtained from orbitally driven marl-limestone alternations from five sections in the basin, and they display the same long-term trends. The spectral analyses present the pervasive recor…
Experimental benchmarking of quantum control in zero-field nuclear magnetic resonance
2017
Zero-field nuclear magnetic resonance (NMR) provides complementary analysis modalities to those of high-field NMR and allows for ultra-high-resolution spectroscopy and measurement of untruncated spin-spin interactions. Unlike for the high-field case, however, universal quantum control -- the ability to perform arbitrary unitary operations -- has not been experimentally demonstrated in zero-field NMR. This is because the Larmor frequency for all spins is identically zero at zero field, making it challenging to individually address different spin species. We realize a composite-pulse technique for arbitrary independent rotations of $^1$H and $^{13}$C spins in a two-spin system. Quantum-inform…
Polarization-driven spin precession of mesospheric sodium atoms
2018
We report experimental results on the first on-sky observation of atomic spin precession of mesospheric sodium driven by polarization modulation of a continuous-wave laser. The magnetic resonance was remotely detected from the ground by observing the enhancement of induced fluorescence when the driving frequency approached the precession frequency of sodium in the mesosphere, between 85 km and 100 km altitude. The experiment was performed at La Palma, and the uncertainty in the measured Larmor frequency ($\approx$260 kHz) corresponded to an error in the geomagnetic field of 0.4 mG. The results are consistent with geomagnetic field models and with the theory of light-atom interaction in the …