Mechanical Therapy With Adjunctive Minocycline Microspheres Reduces Red-Complex Bacteria in Smokers

BACKGROUND

Smoking increases the risk for periodontal disease and reduces the healing response. We examined the antimicrobial and clinical effects of scaling and root planing (SRP) with and without minocycline HCl 1 mg microspheres (MM) relative to smoking status in subjects with periodontitis.

METHODS

A total of 127 subjects (46 never smokers, 44 former smokers, and 37 current smokers) with moderate to advanced periodontitis were randomized to receive MM + SRP (N = 62) or SRP alone (N = 65). Subgingival plaque samples collected at baseline and day 30 were examined for the presence of 40 periodontal bacteria by DNA probe analysis.

RESULTS

MM + SRP reduced red-complex bacteria (RCB) numbers and proportions to a greater extent than SRP alone, irrespective of smoking status. RCB numbers were not reduced by SRP in current smokers. The difference in the reduction in numbers of RCB by SRP relative to MM + SRP in current smokers was statistically significant (P <0.05). Numbers and proportions of orange complex bacteria (OCB) were reduced in all groups treated with MM + SRP. Proportions of OCB increased in current smokers treated with SRP alone. In current smokers, MM + SRP significantly reduced probing depth (PD), increased clinical attachment level (CAL), and reduced bleeding on probing (BOP) to a greater extent than SRP alone (P <0.05).

CONCLUSIONS

SRP alone was ineffective at reducing numbers or proportions of RCB or OCB in current smokers, whereas MM + SRP significantly reduced both. MM + SRP also improved PD, BOP, and CAL to a greater extent than SRP alone independent of smoking status.

Minocycline HCl Microspheres Reduce Red-Complex Bacteria in Periodontal Disease Therapy

BACKGROUND

The objective of this trial was to measure the antimicrobial effects of a minocycline HCl microsphere (MM) local drug-delivery system when used as an adjunct to scaling and root planing (SRP). DNA probe analysis for 40 bacteria was used to evaluate the oral bacteria of 127 subjects with moderate to advanced chronic periodontitis.

METHODS

Subjects were randomly assigned to either SRP alone (N = 65) or MM + SRP (N = 62). The primary endpoints of this study were changes in numbers and proportions of the red-complex bacteria (RCB) and the sum of Porphyromonas gingivalis, Tannerella forsythia (formally T. forsythensis), and Treponema denticola relative to 40 oral bacteria at each test site from baseline to day 30. Numbers of RCB from the five test sites were averaged to provide a value for each subject.

RESULTS

MM + SRP reduced the proportion of RCB by 6.49% and the numbers by 9.4 x 10(5). The reduction in RCB proportions and numbers by SRP alone (5.03% and 5.1 x 10(5), respectively) was significantly less. In addition, MM + SRP reduced probing depth by 1.38 mm (compared to 1.01 mm by SRP alone), bleeding on probing was reduced by 25.2% (compared to 13.8% by SRP alone), and a clinical attachment level gain of 1.16 mm (compared to 0.80 mm by SRP alone) was achieved.

CONCLUSION

These observations support the hypothesis that RCBs are responsible for periodontal disease and that local antimicrobial therapy using MM + SRP effectively reduces numbers of RCBs and their proportions to a greater extent than SRP alone.