Oral hygiene. The most common cause for bad breath originates in the mouth. Poor cleaning and infrequent visits to the dentist are the most frequent factors in bad breath. The tongue has large quantities of naturally occurring bactieria. The back part of the tongue is poorly cleansed by normal activity and the bacteria there feed on food deposits, dead epithelial cells and for some individuals, a post nasal drip. If undisturbed the bacteria can proliferate and produce a number of products which will cause bad breath such as sulphides which have a ‘rotting egg’ smell. Also, plaque, a thin white film containing bacteria, attaches to the teeth and gum. If this material remains on the gums, swelling and bleeding occurs and this is called gingivitis. Regular brushing and flossing will remove the majority of this material. If any remains, such as in difficult to reach areas between teeth or on the inside of teeth, the plaque will physically attach to the tooth and further build up occurs. This material is known as tartar or calculus. This material cannot be brushed or flossed off the teeth and so it has to be removed by the dentist or hygienist. Failure to do this on a regular basis will allow this hard material to build up at and just below the gum line. The gums become sensitive and swollen and bleed, and will continue to get worse, until the material is removed. At this stage bone loss also occurs. As blood breakdowns in the mouth a bad taste and odour will result. Proper cleaning of the gums and between the teeth with floss and interdental brushes will also remove food particles preventing breakdown in the mouth. If you wear a denture the denture should be remove at night, cleaned and placed in water until the next morning.