Is polygon more appropriate than bounding box and mask to detect defect?

[jasonrichdarmawan]

My goal is to detect defect on an object.

The problem is that I am not sure whether bounding box is appropriate to detect defect on an object.

Original image

[jasonrichdarmawan]

Sorry, new user only can upload 1 image per post.

Bounding Box

[jasonrichdarmawan]

Polygon

[jasonrichdarmawan]

Mask