RESPONSE TO INTRACREVICULAR CONTROLLED DELIVERY OF 25-PERCENT TETRACYCLINE FROM POLY(LACTIDE GLYCOLIDE) FILM STRIPS IN SPT PATIENTS/

Controlled local delivery of antibiotics has been shown to reduce peri odontopathic micro-organisms with minimal side-effects. Clinical studi es in our laboratory have shown that 25% tetracycline HCl delivered fr om poly(D,L-lactide/glycolide) film strips (25 TTC-PLGA) released ther apeutic concentrations of tetracycline for 10 days. The present pilot study compared the intracrevicular delivery of 25% tetracycline HCl in corporated in these biodegradable film strips to scaling and root plan ing (SRP) in 10 adult periodontitis patients, who in spite of therapy and regular supportive periodontal treatment (SPT), continued to posse ss 5 bleeding periodontal pockets at least 5 mm deep. Sites were rando mly selected to receive the following treatments: (1) 25 TTC-PLGA, (2) control strips without TTC (PLGA), (3) SRP, and (4) untreated control . Film-strip retention was augmented with a suture/cement technique, f ollowed by strip removal after 2 weeks. Clinical parameters and subgin gival bacterial morphotypes (darkfield analysis) were evaluated over t ime (0, 2,4, 8, 12, 26 weeks). Results indicated that, compared to bas eline, 25 TTC-PLGA film strips caused significant (p less than or equa l to 0.01): (1) probing depth reduction for 26 weeks, (2) a clinical a ttachment level gain for 12 weeks, (3) lower %s of spirochetes for 4 w eeks and motile rods for 8 weeks (p less than or equal to 0.05), and ( 4) an accompanying increase in cocci for 4 weeks. In the scaled and ro ot planed sites, probing depth was the only finding that demonstrated a significant change from baseline (p less than or equal to 0.01). Con trols and PLGA showed isolated reductions in probing depth and % of mo tile organisms. From these findings, applications of intracrevicular 2 5 TTC-PLGA, when compared to scaling and root planing, appears to have an enhanced antibacterial effect and a similar clinical effect in SPT patients. The results of this study indicate further investigation of 25 TTC-PLGA film strips should be undertaken using more subjects and sophisticated microbiological and clinical measurements.