Oral Hygiene is the practice of keeping the mouth clean, and is considered to be the best means of prevention of cavities (dental caries), gingivitis, periodontitis, and other dental disorders. It also helps to prevent bad breath (halitosis).Oral hygiene is necessary for all persons to maintain the health of their teeth and mouth. Healthy teeth have fewer cavities. They are clean and have minimal or no plaque deposits. Healthy gums are pink and firm.