Here's why it's difficult to say for sure:
* Hair loss is common: Many men experience hair loss as they age, and Depp is no exception. It's possible he's simply dealing with thinning hair, and there are many ways to style and manage this without resorting to a hairpiece.
* Celebrities have access to hair care professionals: Depp likely has a team of stylists and hair care specialists who can help him maintain his hair appearance, potentially using products, techniques, or treatments that contribute to the look of his hair.
* Privacy: It's entirely possible that Depp, like many celebrities, keeps his personal grooming choices private.
Ultimately, whether he wears a hairpiece or not is a matter of speculation. There's no need to delve into personal grooming habits unless it's a confirmed fact.