Effects of a single episode of subgingival irrigation with tetracycline HCl or chlorhexidine: A clinical and microbiological study

Background: The present study was designed to evaluate clinical and antimicrobial effects of a single episode of subgingival tetracycline or chlorhexidine (CHX) irrigation in the absence of scaling and root planing. Materials and Methods: Thirty patients diagnosed with chronic periodontitis were recruited for this study, each providing four non-adjacent untreated periodontal pockets with a probing depth equal to or exceeding 6 mm. The four deep periodontal pockets in each patient were assigned to be irrigated with 150 ml each of CHX digluconate 0.2% (group A), tetracycline HCl at concentrations of 10 and 50 mg/ml (groups B and C, respectively), or sterile saline (group D) in a single episode. Recordings of plaque index (PI), gingival index (GI), probing pocket depth (PD), clinical attachment level (CAL), and subgingival bacterial counts from paper point samples were made pre-irrigation (day 0), and at days 7, 28, 56, and 84, post-irrigation. Results: The mean PI and GI scores for all the four groups were reduced post-irrigation, the reduction being significantly higher in group C compared to the other groups. The reduction in the PD and CAL was more significant in group C from day 0 to day 7, whereas the other groups showed minimal changes during this period. The change in the bacterial count was altered towards one of the periodontal health, it being more significant and consistent in the group C. Conclusion: The results of this study suggest that subgingival irrigation with high concentrations of tetracycline may play a beneficial role in the management of chronic periodontitis patients