Bad breath causes range from common oral health problems to rare, gross diseases

If you have halitosis, there are hundreds of bad breath causes that may be giving you oral odor. Some are quite common, while others are exceedingly rare. While the typical origins of halitosis - like tonsil stones, post-nasal drip and tongue coating - are bad enough, some of the uncommon ones can be truly disgusting.

Here, for your education and entertainment, are some of the rarest and most unappetizing bad breath causes imaginable:

- Erosive eosinophilic esophagitis in rumination syndrome (RS). Once thought to only occur in animals, studies have shown that, occasionally, humans can ruminate - that is, pathologically cough up food and re-chew it. This psychological condition, called RS, can lead to erosive eosinophilic esophagitis, a serious throat infection that causes bad breath and large pockets of pus, according to the Jefferson Journal of Psychiatry.

- Maxillary erosion. Drug abuse can lead to this problem, which causes much more than halitosis. The Journal of the Canadian Dental Association reported the case of a man whose years of cocaine snorting eroded a hole in the roof of his mouth the size of a quarter.

- Object in nose. Bad breath can be a sign of having something up the nose, especially if a patient is a child. According to Medscape Reference, the most common thing to be found up kids' noses is a peanut.

- Ozena. The National Institutes of Health states that prolonged, serious nasal infections can cause this condition, in which the bones and mucus membranes of the nose gradually rot.

- Trench mouth. So named because it was one of the most common bad breath causes during World War I, trench mouth occurs when gingivitis gets so bad that it becomes gangrenous.

- Oral myiasis. A very rare condition, this bad breath cause occurs when blowflies lay eggs in the gum tissue. The journal Medico-Legal Update described one of the few recorded cases.