Superstar singer Justin Bieber is known for his boyish good looks, but cosmetic surgeons think that these days he may have had a little ‘help’ to achieve a key part of this youthful appearance.

In a new illuminating video clip, New York City plastic surgeon Dr Gary Linkov revealed convincing evidence that Bieber, 30, has undergone a hair transplant to restore volume in his locks.

Dr Linkov shows two intriguing images that seem to suggest that the singer’s hairline has miraculously changed within the space of two years.

It would also explain why the star has rarely been photographed without a hat on or hoodie covering his head in the past few years.

In one image, taken at the 2022 Super Bowl in Inglewood, California, Bieber — who is married to model and influencer Hailey Bieber, 27 — is seen sporting a shaved head, and his hairline appears to be receding and his hair rather sparse.

But in another image, shared by the star earlier this week, his hair is surprisingly full, with his hairline straight and even.

Bieber was snapped right at the Super Bowl in February 2022 with a hairline that had reversed at the sides of his scalp. But in a photo he posted just last week this appeared to have disappeared, with him now having much fuller locks

In this July 2018 snap taken in New York City, Bieber was photographed with long hair – but again had signs of a receding hairline at the sides of his scalp

Surgeon Dr Gary Linkov said: ‘When I look at his forehead, [the hairline is now] much flatter, it doesn’t have that recession.

‘And when the hair is wet, you can tell the regularity of the [hairline], so it looks like maybe he did have a transplant.’

Dr Jim Harris, a plastic surgeon also in New York City, added: ‘There’s no medication that’s going to turn a receding hairline around. I think, based on [photos], I would say, he has likely had a hair restoration surgery.’

The experts have also highlighted that Bieber frequently steps out in public wearing a hat or a hood, which may have disguised the telltale hair regrowth following a hair transplant procedure.

Dr Linkov said: ‘He started to wear all these hats [in 2022] and he’s covering up his hair so that it’s hard to tell what was going on.

‘And remember, hair transplants can take up to a year, maybe a year and a half, to see final results.’

Dr Harris said: ‘In a photo from 2023 I notice that Justin’s hairline looks flatter.

‘A few years prior to that in 2018, he had a definite recession, very scalloped frontal hairline. [But] now it’s flatter onto his forehead — much more linear.

Surgeons said Bieber had likely received a Follicular Unit Extraction (FUE) to fill in the lost hair, particularly around the top corners of his face.

In this procedure, doctors take hair follicles from the back of the head and implant them into the front to replace lost hair.

It can be done in a way that covers up scarring on the back of the head, making it hard to tell if someone has had the procedure.

Dr Linkov estimated Bieber had had up to 1,800 follicles transferred, at the higher end of the normal amount of 500 to 1,500.

Bieber, pictured above in September 2021 (left) and in the same month (right) attending the Met Gala, was pictured with a thinning hairline at these events

Over the last two years, Bieber has been repeatedly pictured wearing hats or with his hood up — obscuring any changes in his hairline. Surgeons said it could take at least a year for any hair transplant to settle. He is pictured, left, in November 2022 in Los Angeles and in January 2023 in New York City

Estimates suggest about 85 percent of men — including Bieber — suffer from some sort of hair loss in their lifetime, known as male pattern baldness.

This is where hair follicles begin to shrink and die off at the front of the head or at the crown, often linked to age-related shifts in hormones.

Other celebrities that appear to have had similar treatments include 34-year-old singer Machine Gun Kelly and 39-year-old Prince Harry.

Bieber’s hair first showed signs of thinning in 2017 at the age of 23, when surgeons said they could see signs the hairline was receding at the front.

They termed it androgenic alopecia, or when hair follicles shrink over time due to shifts in hormones that shorten the hair growth cycle.

In 2021 Bieber was pictured with dreadlocks, which surgeons warned could cause traction alopecia — a form of hair loss caused by prolonged tension or pulling on the follicles.

In 2022 he was pictured with a drastically reversed hairline on both sides at the front of his head.

There were also reports in 2016 that Bieber, then 21, was suffering parts of hair ‘falling out in clumps’ because of his bleached blonde look.

Bieber has previously slammed Prince William for his receding hairline, saying: ‘I mean, there are things to prevent that nowadays like Propecia [a hair loss drug].

‘I don’t know why he doesn’t just get those things, those products… have you not got it over here?’