The first modern toothbrush was invented in 1938 and pretty much has not improved really nor does it clean your teeth properly in all this time of great advancement and super technology ? Cause you know if there did exist a toothbrush that actually cleaned your teeth properly we would have no need of the dental profession what so ever ! Chew on that awhile. Like they did in 3000 BC. Maybe humans are not as smart as they think they are !