Final answer:
The most appropriate management for tooth 1.4 with caries penetrating one third into the mesial enamel would be to place a direct composite restoration.
Step-by-step explanation:
The most appropriate management for tooth 1.4 with caries penetrating one third into the mesial enamel would be to place a direct composite restoration. A direct composite restoration involves removing the decayed portion of the tooth and filling it with a tooth-colored composite material to restore its shape and function.