Periodontal disease is often challenging to treat because pathogens are protected within an oral biofilm that has an outer slime layer of glycoproteins and mucopolysaccharides that make it difficult for antimicrobials to penetrate.
Root planing and scaling alone cannot completely eliminate pathogens because while this disturbs and moves the biofilm, it does not kill bacteria. As well, this technique does not intentionally address the gum surface, which also harbours bacteria at the site of infection.
Dental biofilms can contain more than 700 different bacterial species and the complexity of structure adds to the challenge of disease control and prevention. The mechanical removal of biofilm is essential but only partially effective. Reorganization of biofilms can be rapid, especially if the initial attachment layer is not destroyed.
Thus combining mechanical removal (by both patient and professional) with an antibiotic rinse can sufficiently disturb biofilm formation to prevent complete rebuilding. Topical rinses have several important advantages over systemic treatment. Antibiotics are delivered in an extremely high concentration, have a high degree of penetration and produce rapid treatment results since particles of antibiotic readily enter the biofilm and are not easily neutralized.
Thus as an adjunct to mechanical removal of plaque and calculus, an antibiotic rinse is one of the most effective and predictable ways of dealing with oral biofilm infections.