Matarazzo turned to Instagram to share with his followers that he would undergo a fourth surgery for his cleidocranial dysplasia, reports aceshowbiz.com.
Uploading a selfie of him flashing a thumbs up to the camera while on a hospital bed, the 17-year-old actor wrote in its caption: "Surgery number 4! This is a big one!" He also encouraged others to "learn more about Cleidocranial Dysplasia and how you can help those with the condition" by directing them to ccdsmiles.org.
Matarazzo's post has since been flooded with words of encouragement from his co-stars.
Millie Bobby Brown, who stars as Eleven in the hit series, wrote to him: "good luck love!!! sending my love gate."
Cara Buono, who portrays Karen Wheeler, said: "Sending you supernova good vibes. Love you."
Matthew Cardarople, who appeared as Keith in three episodes, added: "You're super brave and strong man. Good vibes to you."
The actor has been keeping a positive attitude towards treatment of his disorder.
Back in 2017, he shared a smiling photograph of himself with a note that read: "Yo dudes! A little pre-op pic before my oral surgery today. One step closer to having my own real teeth eventually."
Nearly two years later in March 2019, he updated fans that he was prepped for a third surgery.
( With inputs from IANS )