Halitosis or bad breath, often has dental causes. It can arise from the mere presence of plaque which was not removed by brushing. This in turn later leads to plaque formation that cannot be removed without appropriate tools.
Another determining cause can consist of cavities and their complications, prosthetics which are improperly sanitized, wisdom teeth complications and the occurence of pericoronitis.
Periodontal pockets occuring in periodontal disease are also a cause of bad breath.
The treatment consists of removing the determining causes by sanitation, treatment of cavities and the other dental issues and educating the patient on additional methods of treatment.
If after dental treatment halitosis is not resolved, further investigation is required as halitosis can have a variety of causes besides dental related ones.