Antibiotic gels for periodontal disease

Periodontal disease is a major cause of tooth loss. The underlying pathology is inflammation caused by bacterial plaque affecting the supporting structures of the teeth. Conventional treatment involves mechanical debridement of calcified plaque (calculus) by the dentist combined with meticulous oral hygiene by the patient. A more recent approach is to apply antimicrobial drugs locally to the diseased gingival tissue after debridement. Two antibiotic preparations, minocycline 2% gel (Dentomycin-Lederle) and metronidazole 25% gel (Elyzol-Dumex), are now licensed for the treatment of patients with periodontal disease. Are these treatments an advance on conventional therapy?