Prevention of gingivitis: Oral hygiene and dentifrices

At the basis of Oral Health lies daily oral hygiene self-care with the result, if correctly performed, of plaque and gingivitis reduction. Epidemiological studies indicate that the level of oral hygiene in the general population has increased over the last decades. However, there still appears to be a need for further improvement. While most people claim to brush their teeth twice daily the effectiveness does in general not seem to be sufficient to prevent gingivitis and as a consequence periodontitis. Hence, in this thesis several modifications of oral hygiene devices and toothpastes have been evaluated such as the effectiveness of a toothbrush with a digital feedback monitoring and training system, the risk of gingival recession by brushing with a newly developed power toothbrush and the effectiveness of interdental cleaning devices. Furthermore the contribution of the detergent sodium lauryl sulphate in toothpastes was clinically analyzed and the active ingredients stannous fluoride and triclosan systematically reviewed with regard to parameters of plaque and gingivitis. In conclusion the devices and products investigated like powered toothbrushes, a smart software visualization system, stannous fluoride or triclosan containing toothpastes as well as the correct application of the individually adjusted interdental cleaning device help to improve oral hygiene self-care. More specific, evidence suggests that inter-dental cleaning with interdental brushes is the most effective, interdental oral hygiene device. Toothpastes ingredients triclosan and stannous fluoride contribute comparably to obtain oral health. Sodium lauryl sulphate as ingredient in dentifrices does not improve plaque removal or help to reduce gingivitis. The foaming effect of this detergent is appreciated by patients

Efficacy of inter-dental mechanical plaque control in managing gingivitis - a meta-review

Focused question What is the effect of mechanical inter-dental plaque removal in addition to toothbrushing, on managing gingivitis using various formats of inter-dental self-care in adults based on evidence gathered from existing systematic reviews? Material & Methods Three Internet sources were searched by a strategy designed to include systematic reviews on inter-dental cleaning devices. Plaque and gingivitis scores were the primary parameters of interest. Characteristics of selected papers were extracted. The potential risk of bias was estimated and the acquired evidence was graded. Results Screening of 395 papers resulted in six systematic reviews. Two papers evaluated the efficacy of dental floss, two of inter-dental brushes (IDB), one of woodsticks and one of the oral irrigator. Weak evidence of unclear or small magnitude was retrieved that supported dental floss, woodsticks and the oral irrigator to reduce gingivitis in addition to toothbrushing. No concomitant evidence for an effect on plaque emerged. There is moderate evidence that IDBs in combination with toothbrushing reduce both plaque and gingivitis. Conclusion Evidence suggests that inter-dental cleaning with IDBs is the most effective method for inter-dental plaque removal. The majority of available studies fail to demonstrate that flossing is generally effective in plaque removal. All investigated devices for inter-dental self-care seem to support the management of gingivitis, however, to a varying extend

Multi-messenger Observations of a Binary Neutron Star Merger

International audienceOn 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of $\sim 1.7\,{\rm{s}}$ with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg(2) at a luminosity distance of ${40}_{-8}^{+8}$ Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 $\,{M}_{\odot }$. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at $\sim 40\,{\rm{Mpc}}$) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position $\sim 9$ and $\sim 16$ days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta