Correct usage of D0705 and D0251 ?

I'm sorry. I am not completely understanding your question.
There is a big difference between the codes D0705, D0251 and D0274.

D0274
bitewings - four radiographic images

D0705
extra-oral posterior dental radiographic image - image capture only; Image limited to exposure of complete posterior teeth in both dental arches. This is a unique image that is not derived from another image.

D0251
extra-oral posterior dental radiographic image; Image limited to exposure of complete posterior teeth in both dental arches. This is a unique image that is not derived from another image.

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