Table 1. Characteristics of studies included in systematic review.
| Authors (year) | Country, design | Local setting | Initial Sample (final) | Children with caries (total) | Child’s age at dental examination | Dental examination (calibration) | Feeding habit evaluation | Statistics (adjusted for confounder) | Outcomes (OR, 95% CI) or (p-value) |
|---|---|---|---|---|---|---|---|---|---|
| Al-Dashti et al. (1995) | Kuwait, cross-sectional | One hospital and one health center | 227 | 82(179) were breastfed. 23 (30) had both feeding habits. 12(15) were bottlefed | 18–48 months | 2 dentists | Interview | Chi-square (no) | Breastfed children were affected by caries less frequently than bottle fed children (p<0.05); breastfed and mixed-fed (bottle+breast) children were less often affected by caries than bottle fed children (<0.05); breastfed children were less affected by caries than bottle fed and mixed fed children (p<0.01). |
| Du et al. (2000) | China, cross-sectional | Kindergartens in a suburban area | 426 | 17(34) children bottle fed. 136 (392) children breast fed. | 24–48 months | 3 examiners (k = 0.81–0.86) | Questionnaire for the mothers | Chi-square and Logistic regression (yes) | Bottle fed children were associated with rampant caries (ORadj: 5.27; 95%CI: 2.16–12.89; p = 0.003). Bottle fed children associated with incisor caries (ORadj: 2.38; 95%CI: 1.03–4.76; p = 0.042) Bottle fed children were not associated with dental caries (ORadj: 0.53; 95%CI: 0.26–1.09; p = 0.08) |
| Du et al. (2007) | China, cross-sectional | Two provinces in China. Kindergartens in city and countryside. | 2014 (1621) | 59(130) bottle fed only; 604(1070) children breast fed and 218(421) both feeding habits. | 36–60 months | 3 examiners (k = 0.85 for interexaminer agreement) | Questionnaire for the mothers (urban) and interview (rural). | Chi-square and multivariate regression analysis: logistic and linear regression (yes) | Logistic regression: no significance between feeding habit and dental caries (p>0.05). |
| Qadri et al. (2012) | Syria, cross-sectional | Kindergartens | 400 | 121(192) children were bottle fed. 71 were breastfed. | 36–60 months | 1 pediatric dentist (NR) | Interview with parents | Chi-square, Z statistic, Logistic regression (yes) | Breastfed children were less associated with ECC* (ORadj: 0.27; 95%CI: 0.18–0.41; p<0.001) and less associated with dmft† (OR:0.61; 95%CI: 0.39–0.97; p = 0.038). Higher number of teeth affected by ECC in bottle fed children (p = 0.036) |
| Perera et al. (2014) | Sri Lanka, cross-sectional | Pediatric Unit at the University Hospital | 300 (285) | 88(176) were exclusively breastfed. 48(109) were non exclusively breastfed. | 36–60 months | 2 medical graduates | Interview | Odds ratio and student t test (no) | The mean DEFT did not reveal a statistically significant difference between breastfed children and bottle fed children (p = 0.28). Breastfed children had a higher prevalence of caries than bottle fed children (OR = 1.27; 95% CI = 0.79–2.05). |
| Roberts et al. (1994) | South Africa, case-control | Health centers | 109 cases 109 controls | 34(75) were breastfed. 21(34) were bottlefed | 12–48 months | Examiner (K = 0.95 for intra and interexaminer agreement) | Interview | Chi-square and Wilcoxon test (yes) | No statistically significant difference was found between breastfed children and bottle fed children (p>0.05). |
| Majorana et al. (2014) | Italy, cohort | Obstetric ward of the city hospital | 2517 (2395) | ‡348(588); ‖563(735); ᵜ 492 (534); ¤ 533(538) | 24–30 months | 2 examiners (K = 0.84 for intra examiner agreement) | Questionnaire for the mothers at birth and then with 6, 9 and 12 months, including dietary diary. One clinical examination by the age of 24–30 months. | Ordered logistic regression (yes) | Comparison between exclusively breastfed‡; moderate-high mixed fed‖, low mixed fedᵜ, exclusive artificial formula¤ and caries severity—ICDAS score. Children with a higher proportion of breast milk had a lower ICDAS score (p<0.01, log likelihood = -1956.14, OR (Standard Error) = 6.75 (0.40), 95% CI = 6.00–7.58). |
ORadj = Odds ratio adjusted
ECC = Early childhood caries
† Dmft = decayed tooth, decayed tooth indicated for extraction, filled tooth
‡Exclusive breast milk = 100% breast milk.
‖Moderate-High mixed feeding = 58–99% breast milk.
ᵜLow mixed feeding = 1–57% breast milk.
¤Exclusive use of formula = 0% breast milk.