Five of the seven main castmembers starred in a comedy sketch for US TV show The Tonight Show with Jimmy Fallon but Dustin – who played Screech – was not among them.
Dustin told FOX6 News in America that he only learned about the reunion when a friend texted his girlfriend. He added, however, that he isn't bitter.
"It would have been fun but I don't see it as a personal insult," he said.
The reunion sketch saw Zach (Mark-Paul Gosselaar), Slater (Mario Lopez), Kelly (Tiffani Thiessen), Jessie (Elizabeth Berkley) and Mr Belding (Denis Haskins) imaging what Bayside High would have been like if Jimmy Fallon had also attended.
Dustin - who has also appeared in Celebrity Big Brother - wasn't the only castmember missing. Lark Voorhies, who played Lisa Turtle, was also absent.
It may not have come as a surprise to some viewers that Dustin was absent given what a difficult year he's had so far.
He was arrested on Christmas Day after becoming embroiled in an altercation at a bar and has pleaded not guilty to charges of recklessly endangering safety, carrying a concealed weapon and disorderly conduct, according to BBC News.
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