Cementum Attachment after Treatment with either Citric Acid or Tetracycline

Objectives: Two commonly recommended demineralizing agents for new connective tissue attachment to cementum are citric acid and tetracycline, however, direct comparisons of outcomes are lacking. The present study compares directly in vivo wound-healing responses after surface demineralization with either citric acid or tetracycline.

Methods: Cementum specimens were obtained from areas beneath attached periodontal ligament fibers on extracted normal human teeth. Each rectangular specimen had a face of root surface cementum and an opposite surface composed of pulpal dentin. One group was treated with citric acid alone (pH 1 for 3 minutes), a second group with tetracycline alone (200 mg/cc for 5 min); and a third group was untreated controls. Specimens were implanted transcutaneously into incisional wounds on the dorsal surface of rats with one end protruding through the skin. Four specimens in each group were available for examination 1 and 10 days after implantation. Histologic and statistical histometric analyses of the root surface included counts of adhering cells, evaluation of connective tissue fiber relationships, and assessment of epithelial migration.

Results: At 1 day, zones of surface demineralization were present on Citric Acid and Tetracycline groups, and these groups had numerically greater cell attachment than control surfaces. At 10 days, cell attachment was reduced in all groups, but both Citric Acid and Tetracycline groups had significantly greater cell attachment than controls (p<0.01). Connective tissue fiber attachment occurred on Citric Acid treated specimens, but was absent from Tetracycline treated, and control surfaces. Tetracycline and control specimens were exfoliating.

Conclusions: Citric Acid and Tetracycline surface demineralization both enhanced early wound-healing cell attachment to the cementum surfaces, but only the Citric Acid treatment resulted in an outcome of connective tissue fiber attachment to the cementum root surface. Supported by NIDR-7061, Penn Periodontal Fund, and Alpha Omega Foundation.