title: Scaling and root debridement in pregnant women did not result in fewer preterm births.
abstract: METHODS
  Cochrane Central, ISI Web of Science, Medline and reference lists of studies; hand searches in key journals.
  
  
  METHODS
  Randomised controlled trials (RCTs) in any language that included pregnant women with periodontitis or gingivitis comparing scaling and root planing versus no treatment or prophylaxis.
  
  
  METHODS
  Two reviewers extracted data and assessed study quality using the Cochrane risk of bias tool. The primary outcome was the rate of preterm births. Odds ratios were calculated using 2×2 tables and heterogeneity assessed using χ(2) and I(2) tests. Data were synthesised using the fixed effects or random effects models depending on the level of statistical heterogeneity. Studies reporting no events in either arms were excluded. High and low quality studies were synthesised separately. Publication bias was assessed using a funnel plot.
  
  
  RESULTS
  Eleven trials (6558 patients) were included, five were considered to be at low, and the rest at high or medium, risk of bias (4,718 patients). Meta-analysis found no difference in preterm birth rate using the random effects model (odds ratio (OR) = 0.79, 95% confidence interval (CI) 0.58 to 1.06) or using the fixed effects model (OR = 0.93, 95% CI 0.79 to 1.10). Analysing only the higher quality studies, the lack of difference between interventions was even clearer (OR = 1.15, 95% CI 0.95 to 1.40). There was evidence of publication bias.
  
  
  CONCLUSIONS
  Scaling and root debridement in pregnant women with periodontitis or gingivitis does not result in fewer preterm births.
authors.affiliation: Health Policy & Health Services Research, Henry M. Goldman School of Dental Medicine, Boston University, Boston, MA, USA.
authors.forename: Raul
authors.initials: R
authors.lastname: Garcia