Effect of tetracycline on gingival inflammation and alveolar bone resorption in beagles: an individual tooth by tooth analysis.

The effect of systemic tetracycline on gingival inflammation and alveolar bone resorption was studied in beagle dogs. Seventeen dogs were divided into three groups receiving either no treatment, 250 mg tetracycline HCl, or 500 mg tetracycline HCl daily. The severity of gingival inflammation and activity of alveolar bone resorption during a 6-month pretreatment period was compared to a 24-month treatment period for each individual tooth studied. In the first 12 months of treatment there was a significant decrease in the severity of gingival inflammation and the activity of alveolar bone loss in the tetracycline treated dogs. By 24 months of treatment increased gingival inflammation and rate of bone loss was evident in the treated dogs. In the untreated control dogs there was a statistically significant association between the severity of gingival inflammation and activity of alveolar bone resorption about the teeth studied. In the tetracycline treated dogs, no such association existed.