This is an incrustation which is formed upon the teeth, chiefly on the inner portions, through decomposition of the saliva. It varies in color from whitish yellow to a dark brown, and even green. When tartar is allowed to accumulate in large quantities, it often causes absorption of the gums, so that the teeth become loosened and their utility greatly lessened. A person suffering with tartar upon the teeth, generally has bad breath. The tartar should be thoroughly removed from the teeth by a competent dentist, and the teeth should be kept entirely free from any deposit of this sort by means of daily cleansing and thorough brushing. The teeth may be greatly injured by neglect of this precaution.