Objectives: To consider the efficacy of subantimicrobial dose doxycycline (SDD) as an adjunct to scaling and root planing (SRP) when treating smokers and non-smokers with moderate-severe chronic periodontitis (CP).
Methods: A double-blind, randomized, placebo-controlled, clinical trial was conducted. 210 patients, aged 30-75 years, with baseline clinical attachment levels (CAL) and probing depths (PD) 5-9mm were enrolled. At baseline, patients were treated by a standardized episode of SRP, and randomized to receive either adjunctive SDD (20mg doxycycline BID) or placebo for 9 months. Tooth sites were stratified by baseline PD value: moderately diseased sites (baseline PD 4-6mm) and severely diseased sites (baseline PD ³7mm). Treatment group comparisons of per-patient mean CAL and PD changes were performed using appropriate analysis of variance models utilizing smoking status as factor.
Results: Retrospective analysis revealed that 67 subjects (32%) were current smokers. Mean (SE) CAL gains and PD reductions (adjusted for smoking) after 9 months were as follows:
|
|
CAL gain (mm) |
PD reduction (mm) |
||
|
Baseline PD 4-6mm |
Baseline PD ³7mm |
Baseline PD 4-6mm |
Baseline PD ³7mm |
|
|
Non-smokers: SDD (n=66) |
1.29 (0.07) |
2.12 (0.18) |
1.33 (0.07) |
2.35 (0.18) |
|
Non-smokers: Placebo (n=76) |
1.01 (0.07) |
1.55 (0.17) |
1.00 (0.07) |
1.74 (0.17) |
|
Smokers: SDD (n=41) |
1.19 (0.07) |
2.02 (0.22) |
1.19 (0.08) |
2.25 (0.16) |
|
Smokers: Placebo (n=26) |
0.85 (0.09) |
1.88 (0.29) |
0.93 (0.10) |
1.89 (0.21) |
A hierarchical treatment response was observed such that non-smokers who received SDD tended to demonstrate the best treatment response, and smokers who received placebo demonstrated the worst (p<0.01 in moderate sites). The treatment response observed with SDD was broadly equivalent whether patients were smokers or not (p>0.05).
Conclusions: SDD used adjunctively to SRP provides significant benefit for both smokers and non-smokers with CP compared to SRP alone.
Supported by a grant from CollaGenex Pharmaceuticals, Inc.