ADJUNCTIVE SYSTEMIC AND LOCALLY DELIVERED METRONIDAZOLE IN THE TREATMENT OF PERIODONTITIS - A CONTROLLED CLINICAL-STUDY

Objective To compare clinical and microbiological responses following non-surgical treatment of moderate to advanced adult periodontitis usi ng subgingival scaling with and without adjunctive topical or systemic metronidazole. Design A single blind randomised clinical trial of 90 subjects, stratified for periodontitis disease severity and smoking st atus, divided into three treatment groups: 1. Subgingival scaling usin g ultrasonic scalers and local anaesthesia: 2. Subgingival scaling usi ng ultrasonic scalers and local anaesthesia plus seven days of systemi c metronidazole (200 mg tds); 3. Subgingival scaling using ultrasonic scalers and local anaesthesia plus two applications of 25% metronidazo le gel one week apart in all sites with probing depths more than 4 mm. Evaluations were made before treatment, and 8 weeks and 24 weeks post treatment, Main outcome measures Probing depths, probing attachment l evels and bleeding on probing were measured using a Florida probe. Bac terial morphotypes were evaluated with darkfield microscopy. Results w ere analysed for all sites with baseline probing depths equal to or gr eater than Florida probe recordings of 4.6 mm using analysis of varian ce. Results 84 subjects completed the trial and the three treatment gr oups did not differ at baseline for any clinical parameter. Mean probi ng depths were reduced following treatment by greater than 1.6 mm (Gro up 1 = 1.68 mm, Group 2 = 1.62 mm, Group 3 = 1.74 mm at six months pos t treatment) but no significant differences were detected between trea tment groups at any time point. Similarly, no significant differences were detectable between treatments for changes in mean probing attachm ent levels, bleeding on probing, plaque scores or proportions of bacte rial morphotypes. Conclusions This study does not support the routine use of adjunctive metronidazole in the non-surgical treatment of perio dontitis.