The prevalence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Bacteroides forsythus in humans 1 year after 4 randomized treatment modalities

THE RELATIONSHIP BETWEEN PROBING attachment changes in treated periodontal pockets and the prevalence of selected periodontal pathogens was assessed i n 10 patients with adult periodontitis 1 year following randomized therapy. All patients had at least 1 tooth in each quadrant with an inflamed pocket of probing depth greater than or equal to 5 mm and clinical attachment los s and harbored at least one of the following 3 major periodontal pathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, or Bactero ides forsythus. The number of target organisms per site was determined preo peratively; at 1 week; and at 1, 3, 6, and 12 months postoperatively utiliz ing DNA probes. The following clinical parameters were measured and recorde d preoperatively and at 1, 3, 6, and 12 months post-treatment: gingival flu id flow, gingival index, plaque index, probing depth, probing attachment le vel, gingival recession, and bleeding on probing. One quadrant in each pati ent was randomly assigned to 1 of the following 4 treatments: 1) scaling an d root planing; 2) pocket reduction through osseous surgery and apically-po sitioned flap; 3) modi tied Widman flap; and 4) modified Widman flap and to pical application of saturated citric acid at pH 1 for 3 minutes. All 4 tre atments were rendered in one appointment using local anesthesia. No postope rative antibiotics were used, but patients rinsed with 0.12% chlorhexidine for the first 3 months postoperatively and received a prophylaxis every 3 m onths. This investigation revealed: 1) 30.0% of the sites were infected by at least 1 species at 3, 6, and 12 months postoperatively. 2) Failing sites were infected by a high number of both Pg and Bf: These sites had a mean o f 24.2 +/- 9.0 x 10(3) Pg and 93.1 +/- 42.0 x 10(3) Bf, while stable sites had a mean of 6.8 +/- 0.5 x 10(3) Pg and 7.2 +/- 1.2 x 10(3) Bf (P = 0.06 a nd P = 0.05, respectively). 3) The infected sites lost significantly more m ean clinical attachment at 12 months (1.5 +/- 0.5 mm compared to a loss of 0.2 +/- 0.3 mm for uninfected sites, P = 0.017). 4) The infected sites had a significantly greater BOP(67 +/- 14% versus 25 +/- 8% for uninfected site s at 12 months, P = 0.012). 5) The choice of treatment modality did not aff ect the prevalence of the target species at 1 year post-treatment. These re sults suggest that prevalence of microbial pathogens negatively affects the 1 year outcome of periodontal surgical and nonsurgical therapy.