Figure 3. Results of Trials of Systemic Antimicrobials as an Adjunct to Scaling and Root Planing: Point Estimates of Differences in Mean Gain in Clinical Attachment Level and 95% CI Where Available (SRP + antimicrobial vs. SRP alone) in mm (key as for Fig. 1). Note: *Different antimicrobial sub-studies that share control groups. In each case, the total number of patients for the study is listed once only, to avoid double-counting the controls. ^?Not reported or unclear.