title: Multilevel analysis of clinical parameters in chronic periodontitis after root planing/scaling, surgery, and systemic and local antibiotics: 2-year results.
abstract: OBJECTIVE
  Find the periodontal treatment that best maintained clinical results over time evaluated by changes in pocket depth (PD) and clinical attachment level (CAL).
  
  
  METHODS
  229 patients with chronic periodontitis from USA (n=134) and Sweden (n=95) were randomly assigned to eight groups receiving (1) scaling+root planing (SRP) alone or combined with (2) surgery (SURG)+systemic amoxicillin (AMOX)+systemic metronidazole (MET); (3) SURG+local tetracycline (TET); (4) SURG; (5) AMOX+MET+TET; (6) AMOX+MET; (7) TET; and (8) SURG+AMOX+MET+TET. Antibiotics were given immediately after SRP. Plaque, gingival redness, bleeding on probing, suppuration, PD, and CAL were recorded at baseline and after 3, 6, 12, 18, and 24 months. Treatment effects were evaluated by linear multilevel regression and logistic multilevel regression models. We considered only data from sites with a baseline PD of at least 5 mm of 187 patients completing the study.
  
  
  RESULTS
  Surgically treated patients experienced most CAL loss. Adjunctive therapy including SURG was most effective in reducing PD. Combining SURG with AMOX, MET, and TET gave significant clinical benefits. Past and current smoking habits were significant predictors of deeper PD. Only current smoking was a significant predictor of CAL loss. Bleeding, accumulation of plaque, gingival redness, and suppuration were significant predictors of further CAL loss and deeper PD.
  
  
  CONCLUSIONS
  Both surgical and non-surgical therapies can be used to arrest chronic periodontitis. SURG+AMOX+MET+TET gave best maintenance of clinical results.
authors.affiliation: Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.
authors.forename: Ibrahimu
authors.initials: I
authors.lastname: Mdala
authors.forename: Anne D
authors.initials: AD
authors.lastname: Haffajee
authors.forename: Sigmund S
authors.initials: SS
authors.lastname: Socransky
authors.forename: Birgitte Freiesleben
authors.initials: BF
authors.lastname: de Blasio
authors.forename: Magne
authors.initials: M
authors.lastname: Thoresen
authors.forename: Ingar
authors.initials: I
authors.lastname: Olsen
authors.forename: J Max
authors.initials: JM
authors.lastname: Goodson