Deep grooves
The upper (maxillary) second premolar is smaller than the first premolar, as a rule. They differ little in shape. The buccal cusp is less developed in the second than in the first premolar. The root is usually conical and single. Deep grooves are seen on the contacting surfaces. The root canal may be single or bifurcate.The upper first premolar is distinguished from the second premolar by several signs: in the first premolar the the root conical cnd may bifurcate only at the apex; the cusps on the crown are set almost at the same level.medical coding training trains all these.
