Background: The use of estrogen in postmenopausal (or surgically menopausal) women is a common practice. Compliance is problematic in that estimates show only 1/3 of women use hormone replacement therapy (HRT) and only 30% are compliant. Estrogen has many documented benefits including symptomatic relief of hot flashes, improvement of the dry vagina and dyspareunia. Estrogen has been found to improve bone mineral density and increase the high- density lipoprotein portion of a cholesterol panel. To improve compliance and to provide an alternate method of delivery, we propose the use of estrogen which is admixed in toothpaste and propose to study the absorption, rate of build-up and rate of decline.

Hypothesis: Estrogen can potentially be absorbed systemically when toothpaste is admixed with estradiol and is applied in a timed, consistent fashion to postmenopausal or surgically postmenopausal women, not on HRT. Absorption takes place across the buccal mucosa.

Specific Aims:1) To estimate the systemic absorption of estrogen from daily use of estrogen containing toothpaste.

2) To estimate the rate of build-up of serum estrogen levels based upon daily use of toothpaste containing estrogen for eight days.

3) To estimate the rate of decline in serum estrogen levels when the use of estrogen containing toothpaste is discontinued for a week.