Table 1.

DISTRIBUTION OF SUBJECT-LEVEL VARIABLES BY BREAST-FEEDING DURATION

Subject-level factor	Breast-feeding duration (mos)		P-value
	<6 (n=360)	≥6 (n=149)
Gender (%)
Boys	50	49	.78*
Girls	50	51
Hypoplasia (%)
Any teeth	7	7	1.00*
Primary second molars	3	5	.46*
	Mean	Mean
Parent educational level (1–7)	4.33	4.91	<.001†
Family income level (1–7)	4.57	4.85	.11†
	Mean (±SD)	Mean (±SD)
Gestational weeks	39.62±1.92	39.27±2.15	.10‡
Birth weight (kg)	3.50±0.54	3.52±0.56	.69‡
Dental exam age (ys)
Primary dentition	5.15±0.42	5.13±0.34	.64‡
Mixed dentition	9.20±0.70	9.28±0.71	.28‡
Increment	4.05±0.74	4.15±0.68	.18‡
Home tap fluoride (ppm)§
3–5 ys old	0.85±0.48	0.77±0.38	.06‡
5–9 ys old	0.83±0.46	0.77±0.36	.09‡
Daily fluoride intake (mg/day)
3–5 ys old	0.78±0.40	0.75±0.36	.41‡
5–9 ys old	0.71±0.38	0.70±0.35	.79‡
Daily soda pop intake (oz/day)
3–5 ys old	2.33±2.40	1.94±1.72	.04‡
5–9 ys old	3.13±2.48	2.71±2.21	.07‡
Tooth-brushing frequency (per day)
3–5 ys old	1.29±0.52	1.37±0.52	.12 ‡
5–9 ys old	1.48±0.48	1.57±0.47	.08‡

^*P-value from Fisher’s exact test.

^†P-value from Cochran-Armitage trend test.

^‡P-value from t test.

^§New Department of Health and Human Services’ recommendation for optimally fluoridated water. is at 0.7 ppm.