title: Obstetric outcomes after treatment of periodontal disease during pregnancy: systematic review and meta-analysis.
abstract: OBJECTIVE
  To examine whether treatment of periodontal disease with scaling and root planing during pregnancy is associated with a reduction in the preterm birth rate.
  
  
  METHODS
  Systematic review and meta-analysis of randomised controlled trials.
  
  
  METHODS
  Cochrane Central Trials Registry, ISI Web of Science, Medline, and reference lists of relevant studies to July 2010; hand searches in key journals.
  
  
  METHODS
  Randomised controlled trials including pregnant women with documented periodontal disease randomised to either treatment with scaling and root planing or no treatment.
  
  
  METHODS
  Data were extracted by two independent investigators, and a consensus was reached with the involvement a third. Methodological quality of the studies was assessed with the Cochrane's risk of bias tool, and trials were considered either high or low quality. The primary outcome was preterm birth (<37 weeks). Secondary outcomes were low birthweight infants (<2500 g), spontaneous abortions/stillbirths, and overall adverse pregnancy outcome (preterm birth <37 weeks and spontaneous abortions/stillbirths).
  
  
  RESULTS
  11 trials (with 6558 women) were included. Five trials were considered to be of high methodological quality (low risk of bias), whereas the rest were low quality (high or unclear risk of bias). Results among low and high quality trials were consistently diverse; low quality trials supported a beneficial effect of treatment, and high quality trials provided clear evidence that no such effect exists. Among high quality studies, treatment had no significant effect on the overall rate of preterm birth (odds ratio 1.15, 95% confidence interval 0.95 to 1.40; P=0.15). Furthermore, treatment did not reduce the rate of low birthweight infants (odds ratio 1.07, 0.85 to 1.36; P=0.55), spontaneous abortions/stillbirths (0.79, 0.51 to 1.22; P=0.28), or overall adverse pregnancy outcome (preterm births <37 weeks and spontaneous abortions/stillbirths) (1.09, 0.91 to 1.30; P=0.34).
  
  
  CONCLUSIONS
  Treatment of periodontal disease with scaling and root planing cannot be considered to be an efficient way of reducing the incidence of preterm birth. Women may be advised to have periodical dental examinations during pregnancy to test their dental status and may have treatment for periodontal disease. However, they should be told that such treatment during pregnancy is unlikely to reduce the risk of preterm birth or low birthweight infants.
authors.affiliation: Section of Obstetrics and Gynaecology, Panhellenic Association for Continual Medical Research (PACMeR), Athens, Greece. n.polyzos@gmail.com
authors.forename: Nikolaos P
authors.initials: NP
authors.lastname: Polyzos
authors.forename: Ilias P
authors.initials: IP
authors.lastname: Polyzos
authors.forename: Apostolos
authors.initials: A
authors.lastname: Zavos
authors.forename: Antonis
authors.initials: A
authors.lastname: Valachis
authors.forename: Davide
authors.initials: D
authors.lastname: Mauri
authors.forename: Evangelos G
authors.initials: EG
authors.lastname: Papanikolaou
authors.forename: Spyridon
authors.initials: S
authors.lastname: Tzioras
authors.forename: Daniel
authors.initials: D
authors.lastname: Weber
authors.forename: Ioannis E
authors.initials: IE
authors.lastname: Messinis
mesh_terms: D000022:Abortion, Spontaneous / Q000209:etiology; D012534:Dental Scaling; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D010510:Periodontal Diseases / Q000628:therapy*; D011247:Pregnancy; D011256:Pregnancy Outcome; D047928:Premature Birth / Q000517:prevention & control*; D011295:Prenatal Care / Q000379:methods*; D017594:Publication Bias; D016032:Randomized Controlled Trials as Topic; D016745:Root Planing