Timing affects the clinical outcome of adjunctive systemic antibiotic therapy for generalized aggressive periodontitis.
BACKGROUND
Systemic antibiotics improve the outcome of scaling and root planing (SRP) in patients exhibiting severe periodontitis. This study evaluated the influence of timing of adjunctive systemic antibiotics in the sequence of periodontal therapy.


METHODS
Two cohorts of patients with generalized aggressive periodontitis and treated by SRP, adjunctive antibiotics, and supportive periodontal therapy (SPT) were analyzed retrospectively. Cohort A (17 patients; 36 +/- 5 years of age) received systemic amoxicillin/metronidazole immediately after SRP ("immediate"); cohort B (17 patients; 36 +/- 4 years of age) received the same regimen 3 months after SRP, following SPT, including subgingival reinstrumentation ("late"). Clinical parameters, including probing depth (PD), relative attachment level (RAL), bleeding on probing (BOP), and suppuration, were recorded with a pressure-sensitive electronic probe at baseline and 3 and 6 months after SRP.


RESULTS
Significant time*group interactions were found for all clinical parameters except BOP, i.e., timing of antibiotic therapy affected the course of clinical changes over time. Immediate antibiotic therapy produced significantly higher initial changes (0 to 3 months) in PD and RAL. Late antibiotic therapy at 3 months resulted in additional significant improvements in all clinical parameters between 3 and 6 months. In initially deep sites (baseline PD >6 mm), improvements in PD and RAL over 6 months were significantly higher with immediate antibiotic therapy compared to late antibiotic therapy.


CONCLUSIONS
Within the limits of a retrospective analysis, these findings indicate that administration of amoxicillin/metronidazole immediately after initial SRP provides more PD reduction and RAL "gain" in initially deep sites than late administration at SPT with reinstrumentation after 3 months.
Kaner
Doğan
D
Institute for Periodontology and Synoptic Dentistry, Charité - Universitätsmedizin Berlin, Berlin, Germany. dogan.kaner@charite.de
Christan
Claudia
C
Dietrich
Thomas
T
Bernimoulin
Jean-Pierre
JP
Kleber
Bernd-Michael
BM
Friedmann
Anton
A
D000328:Adult; D000658:Amoxicillin / Q000008:administration & dosage*; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D003131:Combined Modality Therapy; D012534:Dental Scaling / Q000379:methods*; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D008795:Metronidazole / Q000008:administration & dosage*; D010512:Periodontal Index; D010518:Periodontitis / Q000188:drug therapy*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D008795:Metronidazole; D000658:Amoxicillin