上歯 is read as うわば (uwaba) and means upper teeth.
うわば
uwaba
じょうえん
performance (of a play, opera, etc.)
じょうりゅう
upper classes
うわむき
pointing up
じょうたつ
communication of opinions of the general populace to those of high rank
じょうとう
(that's) just fine!
のぼりちょうし
rise
うわむく
to improve
じょうざ
chief seat
うわまわる
to exceed (esp. figures: profits, unemployment rate, etc.)
うわっちょうし
flippant
じょうい
higher order (e.g. byte)
じょうぶ
top part