Scaling and root debridement comprises of the professional removal of calculus (tartar) and plaque (bacterial biofilm) from the surface of the tooth crown and root. It is carried out on the tooth surfaces both above and below the gum line. It is usually done under local anaesthetic to increase patient comfort. Both ultrasonic tools and hand instruments are utilised to carry out this procedure. The procedure is a part of initial phase gum therapy which is designed to greatly diminish the number of disease causing oral bacteria.