Periodontal treatment is the specialist cleaning of your teeth and gums to help control the bacteria that cause gum disease. Gum disease is caused by the germs (bacteria) which live in your mouth. The bacteria stick to your teeth, irritate the gums and make them bleed.
(Redirected from Ground effect in aircraft) In fixed-wing aircraft, ground effect is the increased lift (force) and decreased aerodynamic drag that an aircraft's wings generate when they are close to a fixed surface. When landing, ground effect can give the pilot the feeling that the aircraft is floating.
Ground effect is still the most efficient form of powered flight known to man. The Wright brothers used ground effect when they flew their first aircraft the 'Flyer' in 1903. It took a further six years for the brothers to find an engine big enough and light enough to lift the same aircraft out of ground effect into free flight.