title: Outcomes of non-surgical periodontal treatment by dental hygienists in training: impact of site- and patient-level factors.
abstract: OBJECTIVE
  To investigate the site- and patient-level factors that impact on the response to non-surgical periodontal therapy in patients with chronic periodontitis.
  
  
  METHODS
  A retrospective evaluation of clinical outcomes following non-surgical periodontal therapy delivered by dental hygienists in training was undertaken. Case notes from 195 patients with chronic periodontitis were reviewed and clinical data pre- and post-treatment abstracted. Patients were categorized as 'responders' or 'non-responders' according to defined outcome criteria, and the relationship between clinical and demographic variables and treatment outcomes was assessed.
  
  
  RESULTS
  Overall, there was a good response to the periodontal treatment. At deep sites (those with pretreatment probing depth ≥5 mm), the mean probing depth reduction was 1.6 ± 0.9 mm. Seventy-one (36%) patients were classified as non-responders (indicating that at least 30% of their deep sites did not improve by at least 2 mm following treatment). The non-responding group contained a significantly greater proportion of smokers (28%) than the responding group (16%). Plaque scores did not differ significantly between responders or non-responders either pre- or post-treatment. Regression analyses indicated that smoking status (odds ratio, OR: 2.04), mean pretreatment probing depth (OR: 1.49) and percentage of deep sites ≥5 mm at pretreatment (OR: 1.02) were significantly associated with response to treatment.
  
  
  CONCLUSIONS
  This study supports the benefits of non-surgical therapy in the treatment of chronic periodontitis by dental hygienists in training. Better responses to treatment tend to be observed in non-smokers and in those with less advanced periodontitis at baseline.
authors.affiliation: School of Dental Sciences and Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: P M
authors.initials: PM
authors.lastname: Preshaw
authors.forename: R
authors.initials: R
authors.lastname: Holliday
authors.forename: H
authors.initials: H
authors.lastname: Law
authors.forename: P A
authors.initials: PA
authors.lastname: Heasman
mesh_terms: D055113:Chronic Periodontitis / Q000145:classification / Q000628:therapy*; D015331:Cohort Studies; D003756:Dental Hygienists / Q000193:education*; D003773:Dental Plaque / Q000628:therapy; D003774:Dental Plaque Index; D012534:Dental Scaling / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D005884:Gingival Hemorrhage / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009042:Motivation; D009910:Oral Hygiene / Q000193:education; D057747:Periodontal Debridement / Q000379:methods*; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000145:classification / Q000628:therapy; D012189:Retrospective Studies; D016745:Root Planing / Q000379:methods; D012907:Smoking; D016896:Treatment Outcome
keywords: chronic periodontitis; periodontal therapy; risk factors; smoking; treatment outcomes