Quadrant root planing versus same-day full-mouth root planing. II. Microbiological findings

The aim of this study was to test the hypothesis that over a period of 6 months, same-day full-mouth scaling and root planing (FM-SRP) resulted in greater reductions in the detection frequency of five putative periodontal pathogens compared with quadrant scaling and root planing (Q-SRP) in chronic periodontitis patients.

Forty patients were recruited into this study. Subjects were randomised into two groups. The FM-SRP group received full-mouth scaling and root planing completed within the same day, while the Q-SRP group received quadrant root planing at 2-weekly intervals over four consecutive sessions. Selected-site analyses were performed on the deepest site in each quadrant before and after therapy, at approximately 3 and 6 months from baseline (R1 and R2) and clinical indices were recorded with an electronic pressure-sensitive probe. In addition, subgingival plaque samples were collected from these sites at baseline (BAS), at reassessment 1 (R1), approximately 6 weeks after the completion of therapy and at reassessment 2 (R2), 6 months from baseline. Polymerase chain reaction (PCR) was used to determine the presence of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Treponema denticola and Bacteroides forsythus in plaque.

Both therapies resulted in significant improvements in all clinical indices both at R1 and R2. A marked reduction in the presence of all candidate periodontal pathogens was noted after both treatment modalities, reaching statistical significance for the majority of the test organisms. These improvements were maintained over a period of 6 months. When the two treatment groups were compared, a significantly higher percentage of Q-SRP patients was positive for P. intermedia at R1 compared with FM-SRP patients (p<0.05). In addition, a greater reduction in the patient prevalence for T. denticola was found for the FM-SRP group than the Q-SRP group at R1 and R2 from baseline (p<0.005), but the significance of this is questionable given the skewed detection frequency of this organism at baseline between the two treatments (p<0.01).

This study failed to confirm that same-day FM-SRP resulted in greater microbiological improvements compared with Q-SRP at 2-weekly intervals over a 6-month period, as determined by PCR.