The present study evaluated the clinical response of
periodontal pockets in beagle dogs
after treatment with a biodegradable delivery system containing 10%
doxycycline hyclate (ABDS-D). Eight adult, female beagle dogs had generalized, severe
periodontitis with plaque and
calculus-laden pockets. In each animal, 3 teeth with multiple pocket sites > or = 4 mm (mean depth = 6.0 mm) associated with attachment loss (mean = 5.4 mm) and which bled on probing (mean score = 2.5) were treated with a single application of either ABDS-D (experimental group) or the delivery system alone without the
doxycycline (control group). Residual
polymer was removed at day 7. Bioassay of
doxycycline in gingival crevicular fluid associated with presence of ABDS-D gave mean levels of bioactivity of approximately 250 micrograms/ml. Levels of bioactive
doxycycline were detected for approximately 7 days after ABDS-D removal. Periodontal maintenance consisted of thrice-weekly
toothbrushing the treated sites. Clinical responses were evaluated at 2 weeks, and at bi-weekly intervals thereafter for 4 months. Analyses of the data from the control group showed that there was only slight clinical improvement. In contrast, in the experimental group,
bleeding on probing and probing depths were significantly reduced from baseline at all post-treatment time points. At 1 month, mean probing depth reduction was 2.4 mm and this was maintained at 4 months (mean reduction = 2.5 mm). These probing depth reductions occurred primarily through gain of clinical attachment which was 2.0 mm at 4 months.
Bleeding had been virtually eliminated (mean = 0.2). It was concluded that, for the beagle dogs with severely infected
periodontal pockets in this study, treatment with subgingival
doxycycline using the delivery system resulted in substantial improvement in periodontal health.