RESUMEN
Considering the high prevalence of preterm birth (PTB) and low birth weight (LBW) and their complications as well as the role played by periodontal disease in their incidence and the lack of any report of periodontal therapy on these problems in Iran, the goal of the present research was to determine the effects of periodontal treatment on PLBW incidence among women with moderate or advanced periodontitis who were referred to Javaheri hospital (2004-2005). This clinical trial research was conducted on 30 pregnant women age ranging from 18-35 years old, with moderate or advanced periodontitis. Fifteen subjects randomly underwent the first phase of periodontal treatment including scaling, root planning and the use of 0.2% chlorhexidine mouth rinse for one week. None of these steps were taken for the controls. After necessary follow ups, the effect of periodontal treatment on birth term and birth weight were analyzed statistically. This research was conducted on 30 subjects, 15 controls and 15 cases in study group. In the control group, the observed rate of PLBW was 26.7% whereas among periodontally treated group, phase I, PLBW infant was not observed (P < 0.05). Infants birth weight were (3059.3-389.7) gms in study group and (3371-394.2) gms in the control group and respectively (P < 0.05). Periodontal therapy, phase I, results in a reduction in PLBW incidence rate. Therefore, the application of such a simple method among periodontally diseased pregnant women is recommended.