The study was carried out in 88 children with severe early childhood caries (dmfs≥age +1) who were referred to the investigators' clinic. Patients who completed dental treatment under general anesthesia in a single session, were included to the study.

Patients were divided randomly into 4 groups and after dental treatment one of the fluoride varnish listed below was applied to each child. The groups were as follows;

1. Duraphat varnish containing 5% Sodium Fluoride (Colgate) (n = 22),
2. Clinpro ™ White Varnish containing 5% of Sodium Fluoride tricalcium phosphate (3M ESPE) (n = 22),
3. Embrace ™ Varnish containing 5% Sodium Fluoride with CXP ™ (Pulpdent) (n = 22),
4. MI Varnish containing 5% Sodium Fluoride casein phosphopeptide amorphous calcium phosphate varnish (GC) (n = 22).

Saliva Mutans streptococci (MS) and Lactobacilli (LB) levels, were evaluated by taking saliva samples before general anaesthesia; one month after treatment and three months after treatment.

Duraphat (Colgate), which we used as a positive control group in our study, contains only 5% sodium fluoride. It has been reported in studies that Duraphat is effective in remineralization.

Clinpro ™ White Varnish, another topical varnish in this study,was reported to be effective for caries prevention in pre-school children.

One of the varnishes we evaluate in the study, Embrace™ Varnish, contains 5% sodium fluoride with xylitol-coated calcium and phosphate. According to the manufacturer, the xylitol coating prevents the calcium and phosphate salts from reacting until they come in contact with saliva. Saliva dissolves the xylitol and releases the calcium and phosphate ions, which react with the fluoride ions in saliva to form protective fluorapatite on the teeth19 MI Varnish, in the fourth group containing 5% sodium fluoride with casein phosphopeptide amorphous calcium phosphate (CPP-ACP) had a high release of calcium and fluoride ions.

Inclusion Criteria:

• clinical diagnosis of healthy children with severe early childhood caries,
• younger than 6 years in the primary dentition

Exclusion Criteria:

• history of any chronic disease,
• use of any drugs that reduce salivary flow or antibiotics in the last 4 weeks,
• use of systemic fluoride tablets