Deciduous teeth first teeth seen in the mouth are the mandibular centrals and the last are the maxillary second molars. The primary teeth are made up of central incisors, lateral incisors, canines, first molars, and secondary molars; there is one in each quadrant, making a total of four of each tooth. All of these are gradually replaced with a permanent counterpart except for the primary first and second molars; they are replaced by premolars. The replacement of primary teeth begins around age six, when the permanent teeth start to appear in the mouth, resulting in mixed dentition. The erupting permanent teeth cause
U Should've Known Better producers, which included Dallas Austin, production team Soulshock & Karlin, Bryan Michael Cox, and Rodney Jerkins and his Darkchild crew. Though she "had never thought about writing much" by then, her producers encouraged the singer to intensify her work on the "All Eyez on Me" album and to write and contribute own lyrics and ideas to the songs, one of which was the ballad "U Should've Known Better." Monica penned the song along with Harold Lilly and longtime contributor Jermaine Dupri, while production on the track was helmed by Dupri and Bryan Michael Cox. "U Should've Known Better" was mixed