Topical application of tetracycline in regenerative periodontal surgery in beagles

This study was designed to test the effect of tetracycline on healing subsequent to periodontal surgery. Aqueous solutions of tetracyclines are highly acidic and may therefore represent a suitable substitute for citric acid. Furthermore, tetracyclines react with dental hard tissues to from long-lasting antimicrobial compounds, and they have a retarding effect on pellicle and plaque formation and an antienzymatic effect. The alveolar bone around mandibular premolars was surgically reduced up to 6 mm from the cementoenamel junction in two beagles. The denuded root surfaces were exposed to the oral environment during 3 months without plaque control. Regenerative surgery was then carried out, using root surface conditioning with 1% tetracycline and coronally repositioned flaps. Six months later, histologic evaluation showed connective tissue attachment extending to the cementoenamel junction in most of the specimens. Superficial root resorption was prevalent in the cervical region, below which a collar of replacement resorption partly surrounded the roots in a characteristic manner. Morphometric analysis showed that attachment gain was similar to that obtained with citric acid in a preceding series of seven dogs. These preliminary results indicate that connective tissue attachment gain after topical use of tetracycline is similar to that obtained with citric acid. In addition, the antibacterial capacity and biological effects of tetracycline warrant further study of its possible clinical use in periodontal reconstructive surgery.