Search results for "Recession"
showing 10 items of 250 documents
Definition of Gingival Recession and Anatomical Considerations
2018
The gingiva is an integral part of the periodontium that covers the cervical portions of the teeth and the alveolar processes of the jaws. In health, the closely adapted gingival tissues provide effective protection against mechanical trauma and bacterial invasion and also play a critical role in aesthetics. Therefore, a recession of the gingival margin not only affects the aesthetic appearance but may cause several adverse consequences due to exposure of the root surface. This chapter provides a definition of gingival recession and gives a basic overview of the anatomical characteristics of the gingiva. A basic understanding of the macroscopic and microscopic features of healthy gingiva is…
Progress towards the first measurement of charm baryon dipole moments
2021
Electromagnetic dipole moments of short-lived particles are sensitive to physics within and beyond the Standard Model of particle physics but have not been accessible experimentally to date. To perform such measurements it has been proposed to exploit the spin precession of channeled particles in bent crystals at the LHC. Progress that enables the first measurement of charm baryon dipole moments is reported. In particular, the design and characterization on beam of silicon and germanium bent crystal prototypes, the optimization of the experimental setup, and advanced analysis techniques are discussed. Sensitivity studies show that first measurements of $\Lambda_c^+$ and $\Xi_c^+$ baryon dip…
Morphea “en coup de sabre”: an unusual oral presentation
2017
Morphea, or localized scleroderma, is an inflammatory disease that leads to sclerosis of the skin and underlying tissues due to excessive collagen deposition. Oral involvement is unusual and it may produce white linear fibrotic areas with a scar-like appearance, atrophy of tongue papillae, gingival recession and alveolar bone resorption. We report a case of a 13-year-old girl who consulted for progressive recession on the attached gingiva of her upper left incisors. She also presented a hypopigmented line on the left side skin of her upper lip, which continued through the vermilion and the lip mucosa, including the gingiva of the affected teeth. Clinical examination, blood tests, computeriz…
Impact of Global Economic Crisis on the European Welfare States
2013
The global economic crisis and the subsequent weaker growth are putting under pressure welfare states in the EU. This paper aims at discussing the effects of the crisis at the social level and at identifying whether the classic European welfare state models (Nordic, Continental, Anglo-Saxon and Mediterranean) are still valid in today’s economy. An answer will be tried using the mathematical tool of principal components analysis. The results will be observed in graphs where the states taken into consideration respect the classical welfare models or they regroup themselves into new circumstances’ adapted models. Even though the classical welfare models are generally still checked up with the …
Oral hygiene and periodontal health status among khat chewers. A case-control study
2016
Background Habitual khat chewing is a widespread male habit in Southern Arabia and East Africa. The aim of this study was to assess the effect of Khat chewing on oral hygiene and periodontal health status among Yemeni male khat chewers. Material and Methods This case- control study included 310 khat chewers, aged 20-65 years, and 72 age- and gender- matched non-chewers as controls. Periodontal examination included recording of dental plaque index (PI), gingival index (GI), probing pocket depth (PPD), attachment level (AL) and gingival recession (GR). Demographic data, oral hygiene practices, and duration, frequency and site of khat chewing were obtained using questionnaires. SPSS was used f…
Etiology and Prevalence of Gingival Recession
2018
Gingival recession is a highly prevalent problem affecting individuals of all ages worldwide. Before considering any therapeutic strategies for gingival recession defects, it is important to identify the underlying etiological factors that contributed to the development of the clinical condition. The main etiological factors for gingival recession are plaque-induced periodontal inflammation and mechanical trauma caused by improper toothbrushing habits. Several other predisposing and precipitating factors have also been implicated in the etiology of gingival recession. The aim of this chapter is to summarize the different etiological factors contributing to the development of gingival recess…
Healing of intrabony defects following surgical treatment with or without an Er:YAG laser. A pilot study
2004
Aim: The aim of this controlled, parallel design clinical study was to compare the healing of intrabony periodontal defects following treatment with access flap surgery with and without debridement with an Er:YAG laser. Methods: Twenty-three patients each of whom exhibited one deep intrabony defect were randomly treated with either access flap surgery followed by root surface and defect debridement using an Er:YAG laser (KEY3®) (160 mJ, 10 Hz) (test), or with access flap surgery followed by root surface and defect debridement using hand and ultrasonic instruments (control). The following clinical parameters were recorded at baseline and at 6 months: plaque index; gingival index; bleeding on…
Application of spin-exchange relaxation-free magnetometry to the Cosmic Axion Spin Precession Experiment
2018
The Cosmic Axion Spin Precession Experiment (CASPEr) seeks to measure oscillating torques on nuclear spins caused by axion or axion-like-particle (ALP) dark matter via nuclear magnetic resonance (NMR) techniques. A sample spin-polarized along a leading magnetic field experiences a resonance when the Larmor frequency matches the axion/ALP Compton frequency, generating precessing transverse nuclear magnetization. Here we demonstrate a Spin-Exchange Relaxation-Free (SERF) magnetometer with sensitivity $\approx 1~{\rm fT/\sqrt{Hz}}$ and an effective sensing volume of 0.1 $\rm{cm^3}$ that may be useful for NMR detection in CASPEr. A potential drawback of SERF-magnetometer-based NMR detection is …
Magnetic field uniformity in neutron electric dipole moment experiments
2019
© 2019 American Physical Society. Magnetic-field uniformity is of the utmost importance in experiments to measure the electric dipole moment of the neutron. A general parametrization of the magnetic field in terms of harmonic polynomial modes is proposed, going beyond the linear-gradients approximation. We review the main undesirable effects of nonuniformities: depolarization of ultracold neutrons and Larmor frequency shifts of neutrons and mercury atoms. The theoretical predictions for these effects were verified by dedicated measurements with the single-chamber neutron electric-dipole-moment apparatus installed at the Paul Scherrer Institute. ispartof: Physical Review A vol:99 issue:4 sta…
Test of Lorentz invariance with spin precession of ultracold neutrons
2009
A clock comparison experiment, analyzing the ratio of spin precession frequencies of stored ultracold neutrons and $^{199}$Hg atoms is reported. %57 No daily variation of this ratio could be found, from which is set an upper limit on the Lorentz invariance violating cosmic anisotropy field $b_{\bot} < 2 \times 10^{-20} {\rm eV}$ (95% C.L.). This is the first limit for the free neutron. This result is also interpreted as a direct limit on the gravitational dipole moment of the neutron $|g_n| < 0.3 $eV/$c^2$ m from a spin-dependent interaction with the Sun. Analyzing the gravitational interaction with the Earth, based on previous data, yields a more stringent limit $|g_n| < 3 \times …