Tetracycline and Staining of the Teeth

Abstract

<h3>To the Editor.—</h3> In their recent article on minocycline staining of already erupted permanent teeth, Poliak et al¹state that tetracycline stains teeth only when it is administered before the age of 7 years. They go on to speculate that "tetracycline's inability to stain the teeth beyond the age of 7 years may be a function of the unavailability of free calcium for complexing." The first statement is in error and the speculation is unnecessary. Tetracycline will bind to teeth (and to bone) whenever active calcification is taking place.²For teeth, this means from the second trimester of fetal life until the roots of the third molars are complete in late adolescence. In terms of clinical significance, tetracycline tooth staining of the usual type is important only for the highly visible anterior teeth (incisors, cuspids, and bicuspids). These teeth complete their crown formation by the age of 6