Kòe-liōng ê fluoride khip-siu mā-ē ín-khí chhùi-khí ê hu̍t-tiòng-to̍k (dental fluorosis), án-ne ē khòaⁿ-tio̍h chhùi-khí chhut-hiān pan-chōng-khí (mottled tooth) ê chêng-hêng, khah kheng-bî--ê sī chhùi-khí piáu-bīn ū pe̍h-pan, jiân-āu sī nā chiù-khang ê ka-pi-sek khám-khiat, siāng giâm-tiōng--ê sī kui-ki chhùi-khí ê hoat-io̍k-put-choân (hypoplasia). Fluoride ê khip-siu nā chhiau-kòe 2 p.p.m. tio̍h-ē hoat-seng pan-chōng-khí, in-ūi éng-kiú-khí ê mn̂g-khí kap kak-khí ê khí-koan tī 6-hòe chìn-chêng tio̍h hêng-sêng oân-choân, in-chhú 6-hòe chìn-chêng mài hō· gín-á tn̂g-kî thun-chia̍h kòe-liōng ê fluoride, tio̍h ē-tàng phiah-bián pan-chōng-khí ê hoat-seng.