No evidence to support the use of low-dose doxycycline as an adjunct to nonsurgical therapy in smokers

Abstract

This was a randomised, placebo-controlled trial with 6 months of follow-up. Patients received nonsurgical periodontal therapy and 3 months of the test treatment (low-dose doxycycline; LDD) or control (inactive identical placebo). The primary outcome was the change in the clinical attachment level (CAL) recorded from the cemento-enamel junction to the base of the probing pocket using a graduated UNC-15 probe (Hu Friedy, Chicago, Illinois, USA). Secondary outcomes included pocket depth, gingival recession and bleeding on probing recorded at six sites per tooth with the manual probe and ICTP (terminal carboxytelopeptide of type 1 collagen). The velocity of change was statistically significantly greater for the test group for CAL [-0.19 mm/ month; 95% confidence interval (CI), -0.34- -0.04; P 0.012] and probing depth (0.30 mm/ month; 95% CI, -0.42- -0.17; P 0.001). No differences were observed, however, for absolute change in clinical or biochemical markers at 6 months. Nonsurgical periodontal therapy in smokers can produce a substantial improvement in periodontal health but there is no evidence to support the use of LDD as an adjunct to their nonsurgical therapy. Quitting tobacco use continues to be of fundamental importance in improving the periodontal health of these individuals.