Prenatal Oral Health Care and Early Childhood Caries Prevention: A Systematic Review and Meta-Analysis

Abstract

Despite the advancement of early childhood caries (ECC) prediction and treatment, ECC remains a significant public health burden in need of more effective preventive strategies. Pregnancy is an ideal period to promote ECC prevention given the profound influence of maternal oral health and behaviors on children's oral health. However, studies have shown debatable results with respect to the effectiveness of ECC prevention by means of prenatal intervention. Therefore, this study systematically reviewed the scientific evidence relating to the association between prenatal oral health care, ECC incidence, and Streptococcus mutans carriage in children. Five studies (3 randomized control trials, 1 prospective cohort study, and 1 nested case-control study) were included for qualitative assessment. Tested prenatal oral health care included providing fluoride supplements, oral examinations/cleanings, oral health education, dental treatment referrals, and xylitol gum chewing. Four studies that assessed ECC incidence reduction were included in meta-analysis using an unconditional generalized linear mixed effects model with random study effects and age as a covariate. The estimated odds ratio and 95% confidence intervals suggested a protective effect of prenatal oral health care against ECC onset before 4 years of age: 0.12 (0.02, 0.77) at 1 year of age, 0.18 (0.05, 0.63) at 2 years of age, 0.25 (0.09, 0.64) at 3 years of age, and 0.35 (0.12, 1.00) at 4 years of age. Children's S. mutans carriage was also significantly reduced in the intervention group. Future studies should consider testing strategies that restore an expectant mother's oral health to a disease-free state during pregnancy.

Keywords: Child dentistry; Early childhood caries; Prenatal oral health care.

Figure 1.. Modified Fisher-Owens conceptual model of child, family, and community influences on oral health outcomes of children.

Factors underlined in red are those that could potentially be influenced by maternal attributes.

Figure 2.. Flow diagram of study identification.

The four-phase Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram was used to determine the number of studies identified, screened, eligible, and included in the systematic review and meta-analysis (http://www.prisma-statement.org).

Figure 3.. Summary of quality and risk of bias assessment using Cochrane Collaboration’s tool for assessing risk of bias in randomized trials and adapted Down and Black scoring tool.

The quality of the selected articles were assessed using two methodological validities: 1) Cochrane Collaboration’s tool for assessing risk of bias in randomized trials [Higgins et al., 2011]. 2) Adapted Down and Black scoring [Downs and Black, 1998] that assess the methodological quality of both randomized and non-randomized studies of health care interventions. A total score of 26 represents the highest study quality.

Figure 4.. Odds Ratio of ECC events in prenatal oral health care intervention group and control group.

Meta-analysis was performed on four studies that assessed ECC incidence. In particular, Günay et al, 1998 examined the same cohort of children at two time points, when they reached 3- and 4- years of age; their results were included as two data sets in the meta-analysis. Study heterogeneity (I²=75.06%) and the related p-value were calculated using likelihood ratio test (p<0.0001). The empirical odds ratio (OR) and 95% confidence interval (CI) of each study included in the meta-analysis was shown in (A). Based on the generalized linear mixed effect model with covariate age, the estimates of OR and 95% CI shown in (B) indicate that regarding ECC incidence, there is a statistically significant difference between the intervention and control groups for children younger than 4 years of age. The solid line indicates when OR=1.