EVALUATION OF CITRIC ACID AND TETRACYCLINE HYDROCHLORIDE AS ROOT CONDITIONERS ON INSTRUMENTED PERIODONTALLY DISEASED ROOT SURFACES -- A COMPARATIVE SEM STUDY.

Background: Periodontally-diseased cementum surface contaminants inhibit growth and viability of fibroblasts and prevent the new connective tissue attachment. Thus, the removal of infected cementum has been advocated in periodontal therapy. These root surfaces decontaminated mechanically by hand instruments produce a smear layer. Acid conditioning of root surfaces after instrumentation has been used for removing endotoxins and smear layer. Citric acid and tetracycline hydrochloride have received great attention. Materials and Method: This in-vitro study included three groups -- one control (saline) and two experimental, where saturated solutions of citric acid and tetracycline hydrochloride were used as root conditioning agents on 45 single rooted extracted human teeth from 25 subjects with advanced periodontitis resulting in a sample size of 90. Each root surface was thoroughly planed with 100 strokes using a cut-sharp Gracey curette (11/12). 30 tooth sections were treated with saline. Cotton pellets soaked in citric acid and tetracycline hydrochloride solution were burnished on 30-30 tooth samples respectively. Samples were then mounted on SEM stub and sputter-coated with gold. All specimens were viewed using SEM by a single investigator. Mann Whitney 'U' test, Student's unpaired 't' test and Chi-square test were used to find the significance of results. Results and Conclusion: Citric acid was more efficient in removing smear layer, exposing more number of dentinal tubules and patent tubules than tetracycline hydrochloride. However, statistically no significant difference was found between the two agents as far as the diameter of exposed tubules was concerned. [ABSTRACT FROM AUTHOR]