Final answer:
The radiolucent area on the distal of tooth #13 is a dark area seen on an X-ray image that can indicate dental decay, a cavity, or an abscess. Further examination by a dentist is necessary for accurate diagnosis and treatment.
Step-by-step explanation:
The radiolucent area on the distal of tooth #13 refers to a dark or black area seen on an X-ray image that represents a less dense and less opaque region on the distal side of the tooth.
This radiolucent area can indicate various conditions such as dental decay, a cavity, or an abscess. It is important to note that further diagnostic evaluation and examination by a dentist is necessary to determine the exact cause and appropriate treatment.