Modified-release subantimicrobial dose doxycycline enhances scaling and root planing in subjects with periodontal disease

J Periodontol. 2008 Mar;79(3):440-52. doi: 10.1902/jop.2008.070375.


Background: Previous studies showed that adjunctive subantimicrobial dose doxycycline (SDD; 20 mg, twice daily) provides significant clinical benefits to scaling and root planing (SRP). A modified-release SDD formulation containing 40 mg doxycycline (SDD-40) to be taken once daily has been developed. The aim of this study was to investigate the efficacy of SDD-40 when used as an adjunct to SRP for the treatment of periodontitis.

Methods: A 9-month, double-masked, randomized, placebo-controlled, multicenter study was conducted to test the efficacy of adjunctive SDD-40 in 266 subjects with periodontitis. Subjects were treated by SRP and randomized to receive SDD-40 or placebo for 9 months with evaluations at 3, 6, and 9 months.

Results: Adjunctive SDD-40 provided significantly greater clinical benefits than placebo at all time points. At month 9, at sites with baseline probing depths (PD) > or =6 mm, 72% to 76% of sites in the SDD-40 group demonstrated clinically significant PD reductions and clinical attachment level (CAL) gains > or =2 mm compared to 56% to 58% of sites in the placebo group (P <0.0001); 48% to 52% of sites in the SDD-40 group demonstrated PD reductions and CAL gains > or =3 mm compared to 32% of sites in the placebo group (P <0.0001). In moderate sites (baseline PD 4 to 6 mm), adjunctive SDD-40 provided significant clinical benefits compared to placebo for mean CAL (all time points: P <0.05), PD (3 months: P = 0.002; 6 and 9 months: P = 0.001), and bleeding on probing (BOP) (3 months: P <0.01; 6 months: P <0.02; 9 months: P <0.05). In deep sites (baseline PD > or =7 mm), SDD-40 provided significant benefits over control for mean CAL (3 months: P <0.05; 6 and 9 months: P <0.01), PD (all time points: P <0.001), and BOP (3 months: P <0.05; 6 months: not statistically significant; 9 months: P <0.05). Compliance with study medication was high (>92%) with no significant differences in adverse events between groups and no evidence of microbiologically significant changes or development of antibiotic resistance in the subgingival flora in either group.

Conclusion: SDD-40 used as an adjunct to SRP resulted in significantly greater clinical benefits than SRP alone in the treatment of periodontitis.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Topical
  • Adult
  • Aged
  • Aged, 80 and over
  • Analysis of Variance
  • Anti-Bacterial Agents / administration & dosage*
  • Bacteria, Anaerobic / isolation & purification
  • Colony Count, Microbial
  • Combined Modality Therapy
  • Dental Plaque / microbiology
  • Dental Scaling*
  • Double-Blind Method
  • Doxycycline / administration & dosage*
  • Female
  • Humans
  • Linear Models
  • Male
  • Middle Aged
  • Periodontal Index
  • Periodontitis / drug therapy*
  • Periodontitis / therapy*
  • Statistics, Nonparametric


  • Anti-Bacterial Agents
  • Doxycycline