A Clinical Trial of Phenoxymethyl Penicillin for Adjunctive Treatment of Juvenile Periodontitis

A double‐blind clinical trial of oral penicillin as an adjunct to conventional treatment of localized juvenile periodontitis (JP) was conducted. Sixteen subjects with JP were paired on the basis of general similarity of disease, and within each pair the persons were assigned randomly, one to a placebo group and one to a penicillin group. Neither patients nor therapist/examiner were aware of whether placebo or penicillin was being taken. All subjects received an initial scaling and root planing of all teeth and flap surgery of all affected sites. Every 12 weeks after surgery through Week 62 of the study, root planing and oral hygiene instructions were repeated. Phenoxymethyl penicillin (250 mg qid) or placebo was started the day of surgery and each recall visit and lasted for 10 days. Clinical measurements were made at the beginning of the study and at each recall visit. In both groups there was a significant decrease in plaque scores, gingival inflammation, gingival bleeding and probeable depths for all sites and for affected sites. Similarly there was a significant increase in attachment level and radiographic bone height, and a total elimination of suppuration. The favorable changes were apparent at the first postsurgical recall (Week 26 of the study) and remained essentially the same through Week 62. The magnitude of change in these parameters was similar to that reported by others for treatment regimes including tetracycline therapy. However, there were no differences in any parameters between the placebo and penicillin groups. Half of the subjects (4 in each group) were continued in the study for another 9 months (Week 98). There were still no differences between groups. The data indicated that root planing, flap surgery and maintenance therapy every 3 months provide an effective treatment for juvenile periodontitis, but that treatment results were not enhanced by oral administration of penicillin.