Jersey Shore star Deena Nicole Cortese stepped out for MTV's Spring Break Las Vegas at the Palms Casino Resort on Wednesday night and sported a new look that has critics saying she underwent plastic surgery or a nose job based on before and after photos.

A slimmed down, and of course bronzed, Deena sported a new figure, higher arched eyebrows and a different nose at the Palms.

Many Twitter users noticed her look, and a debate has started as to whether or not Deena went under the knife.

WTF HAPPENED TO HER FACE, wrote Twitter user iKATx.

Dr. Gabriel Chiu of Beverly Hills Plastic Surgery, who has never treated Deena, told Celebuzz.com that he believes her new look can be attributed to some surgery.

Judging by these photos only, it looks like Deena has definitely plumped up her lips with a filler like Juvederm, Chiu said. They are so overfilled, she can't even pucker up to blow a kiss!

Chiu also believes that Deena may have had a small surgery on her nose, as she admitted to undergoing a nose job back in August to the New York Post's Page Six.

Dr. Chiu said she most likely also used a filler like Restylane or Perlane under her eyes, in the apples of her cheeks and jawline in addition to Botox or Dysport in her brows causing the raising/widening of her medial brows.

Her new look appears to be more than just a makeover, though it should be noted that her makeup was much more toned down than usual. Perhaps she took a cue from costar Nicole Snooki Polizzi who has been sporting less makeup and a trim figure, well before she announced her pregnancy earlier this month.

Dr. Chiu told Celebuzz that Deena Nicole Cortese obviously darkened her hair [and] is using different makeup.

View the slideshow to see before and after photos of Jersey Shore's Deena Nicole Cortese and her alleged nose job and surgery.