Scaling and Root Planing Is Effective in Reducing Preterm Birth Only in High-Risk Groups

Selection Criteria RCTs done in pregnant women who had periodontal disease (probing depth >= 4 mm or clinical attachment loss >= 2 mm in at least one site) where the intervention was SRP and at least one outcome was preterm birth (PTB <= 37 weeks) were selected for the analysis. Studies were located by searching MEDLINE (1950-September, 2011), CINAHL (1980-September, 2011), and EBSCO (1990-September 2011). Search was not limited to English language articles. Eleven foreign language studies were later eliminated, as they did not meet inclusion criteria. Hand searches were used to supplement the original search, and both obstetrics and periodontology experts were also contacted. Additional attempts were made to locate unpublished studies by searching Clinical Trial. gov and by reviewing abstracts and specific conference proceedings. Twelve studies were included in the final analysis. Key Study Factor Common intervention was SRP performed on pregnant women. Control groups were not treated for periodontal disease before delivery. Both groups could receive routine dental treatment and oral hygiene instructions. Primary outcome was PTB. Study subjects were on average between 22.8 and 30.5 years of age. Timing of the intervention (SRP) was, however, highly variable (from 6 to 35 weeks of gestation). Main Outcome Measure PTB was the main outcome measure. This was defined as a delivery before 37 weeks of pregnancy. Main Results Sixty-five studies were assessed for eligibility using full text review, and 53 of those were excluded because they failed to meet eligibility criteria. Based on the 12 RCTs included in the study, authors observed a statistically significant reduction in preterm birth as a result of SRP, but only in the high-risk women (pooled risk ratio [RR] = 0.66; 95% confidence interval [CI] = 0.54-0.80). The high-risk group of studies showed a statistically significant reduction in low birth weight incidence as well (RR = 0.48; 95% CI = 0.30-0.78). High risk was defined as having a higher incidence of PTB (>22%) based on the combined PTB incidence in treatment and control groups within each study. Only four studies were included in this analysis, with 88/280 events in the treatment group and 130/275 events in the control group. When all the studies were combined, reduction in PTB was not statistically significant (RR = 0.81; 95% CI = 0.64-1.02). Results were similar for >35 week deliveries, low birth weight incidence, and mean low birth weight. Conclusions Authors concluded that for the general population, there is insufficient evidence to support the need for periodontal disease treatment to reduce preterm birth but periodontal treatment may be beneficial for populations in which the incidence of preterm birth is high.