Generally speaking, a "deep cleaning" is a procedure called scaling and root planing and commonly takes place over several appointments. Scaling and root planing is done if people have deeply imbedded tarter or calculus resulting in gum or periodontal disease. During scaling and root planing, each portion or quadrant of the mouth is anesthetized and the roots are deep cleaned. Because of the use of anesthetic, usually only a quadrant or half of the mouth is done at one appointment. If antibiotics are prescribed, the dental health care provider should tell you prior to the appointment and advise you why the antibiotic was recommended. If you have areas of deeper pockets, particularly with inflammation or localized infection, antibiotics can be useful.