Adjunctive subantimicrobial-dose doxycycline without oral hygiene instruction gives mixed results compared with scaling and root planing alone

Abstract

Objective: To assess the efficacy and safety of subantimicrobial-dose doxycycline (SDD) in conjunction with subgingival scaling and root planing (SRP) in patients with adult periodontitis.Design: Randomised, double-blind, placebo-controlled, parallel-group trial in five United States dental schools.Intervention: Following SRP but no oral hygiene instruction, 30–75-year-old patients with clinical attachment level (CAL) and probing depth (PD) between 5 and 9 mm inclusive and bleeding on probing (BOP) in at least two sites in two quadrants were randomly allocated to receive either doxycycline hyclate 20 mg bid or placebo bid for 9 months. Detailed exclusion criteria are given and all examiners received training prior to the study.Outcome measures: CAL, PD, BOP and microbial assessments were taken at baseline and 3-monthly intervals. Patients recorded adverse events in diaries.Results: Absolute changes in CAL and PD were significantly greater with SDD (Table 1) than with placebo although the proportion of sites showing improvements were not statistically different. BOP remained high in all groups. Improvements occurred without detrimental shifts in normal periodontal flora.Conclusions: The adjunctive use of SDD with SRP is more effective than SRP alone and may represent a new approach in long-term management of adult periodontitis.