Mothers in the experimental group were instructed to chew 1 pellet of xylitol gum (Fennobon Oy, Yrittäjäntie, Finneland -gum, 3 times ) for a period of 3 months. control mothers did not receive any medications. All mothers received oral hygiene instructions and restorative treatment when needed. Offspring of both the experimental and control groups did not receive any medication and were followed for at 6,12, 18 and 24 month from initiation of mothers consumption. month

The control group participated in a preventive program under the supervision of the Pediatric Dentistry Department. The program activities consisted of oral hygiene instructions, fluoride varnish application (Duraphat 5% Na F ,Ultradent Products, Utah, USA) and restorative treatment when needed.

Mothers in the experimental group were instructed to chew 1 pellet of xylitol gum (Fennobon Oy, Yrittäjäntie, Finneland -gum, 3 times ) for a period of 3 months. control mothers did not receive any medications. All mothers received oral hygiene instructions and restorative treatment when needed. Offspring of both the experimental and control groups did not receive any medication and were followed for at 6,12, 18 and 24 month from initiation of mothers consumption. month

Collection of saliva samples was carried out for microbiological screening after 6, 12, 18 and 24 months from the initiation xylitol consumption .Un stimulated saliva samples were collected from each child for salivary bacterial level screening. Saliva sampling was performed before conducting the clinical examination between 9-11 am. Children were not allowed to eat or drink for 2 hours before sampling. Saliva was collected with the pipette supplied by the dentocult (CRT) kit. (Ivoclar Vivadent, Lichtenstein). Saliva sample was not taken if the child has received antibiotics within 1 month prior the examination. Screening of stimulated saliva samples for mutans streptococcus (MS) level were carried out using the dentocult method (CRT). Findings of 105 CFU or more of MS indicates a high caries risk, whereas findings less than 105 CFU is considered low caries risk.

Clinical examination was carried out for dmft score for deciduous teeth after 6, 12, 18 and 24 months from the initiation maternal xylitol consumption. The diagnosis of dental caries was based on the WHO criteria 1987.

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