COST-EFFECTIVENESS OF PROBIOTICS TO PREVENT DENTAL CARIES AMONG YOUNG CHILDREN IN PHAYAO PROVINCE, THAILAND

Abstract

Probiotics have been used to prevent dental caries in children.  In this study we aimed to determine the cost-effectiveness of probiotic milk tablets to prevent dental caries among children who attended 12 selected daycare centers in Phayao Province, Thailand during June 2022-May 2023 in order to determine if probiotic-fortified milk tablets are a reasonable method to prevent dental caries among children aged 2-5 years.  Inclusion criteria for study subjects were being aged 2-5 years, attending one of the study daycare centers and having parental consent to participate the study.  Exclusion criteria for study subjects were cow’s milk allergy, serious medical conditions, such as heart disease or asthma, abnormalities related to the palate or jaw, being unable to undergo an oral health examination or having developmental delay.  Study subjects were divided into a control group and a treatment group.  Treatment group subjects were given 3 milk tablets daily by the caregiver and oral hygiene instructions.  Each milk tablet contained the probiotic Lactobacillus rhamnosus SD11, but the concentration of these organisms in each milk tablet were not recorded by the manufacturer.  Each subject was examined by one of two study dentists at the beginning of study initiation and then every 4 months for 12 months to evaluate for the presence of caries.  The price of the milk tablets and caregiver cost were recorded.  The cost-effectiveness ratio (CER) was calculated as follows: CER = (average cost of caries prevention per child by the milk tablets per year) / (the difference in carious surfaces between the control group and the milk tablet group).  The minimum number of study subjects calculated to be needed for the study was 208 based on the estimated prevalence of caries in the study population.  A total of 260 subjects were initially enrolled in the study: 130 in the control and 130 in the intervention group.  After the 12-month study period, there were a total of 222 participants, with 112 individuals in the control group and 110 individuals in the experimental group.  The mean numbers of caries per subject in the control group at 4, 8 and 12 months were 5.69, 5.60 and 7.31, respectively.  The mean numbers of caries in the intervention group at 4, 8 and 12 months were 3.04, 3.12 and 3.24 respectively.  The p-values for the differences in the mean numbers of caries between the control and intervention groups at 4, 8 and 12 months were p=0.003, p=0.016 and p=0.001, respectively.  The cost-effectiveness analysis showed it cost THB 369.93 to prevent one cavity per tooth surface per year.  In summary, there were significantly fewer caries among study subjects in the intervention group than the control group but the intervention was costly.  We conclude, this intervention can be used effectively to prevent caries in the study population but it was expensive.  Further studies are needed to determine if this intervention can be applied to other populations of similar aged children and other ages of children and how the program can be financed or the cost reduced.