Aimee Lou Wood, a star of HBO’s “The White Lotus,” has criticized “Saturday Night Live” for a sketch that mocked her smile, calling it “mean and unfunny.”

Ms. Wood, a British actress, posted on Instagram on Sunday objecting to the sketch, in which the S.N.L. cast member Sarah Sherman impersonates Ms. Wood’s character while wearing large prosthetic teeth.

“I am not thin skinned,” Ms. Wood, 31, wrote in one of a series of posts on her Instagram stories, adding that she loves being joked about when “it’s clever and in good spirits.” But “the joke was about fluoride. I have big gap teeth not bad teeth,” she wrote.

In a subsequent post, Ms. Wood said she had received “apologies” from S.N.L. but did not elaborate. Representatives for Ms. Wood and NBC, which broadcasts S.N.L., did not immediately respond to requests for comment.

The sketch, titled “The White POTUS,” imagined the show’s characters replaced by President Trump and members of his cabinet. Ms. Wood, who is from Manchester, England, also criticized Ms. Sherman’s impersonation of her Mancunian accent.

After her initial posts, Ms. Wood said that she had since received thousands of messages of support. She shared what appeared to be one such message, which said: “It was a sharp and funny skit until it suddenly took a screeching turn into 1970’s misogyny.”

The third season of “The White Lotus,” which concluded this month and was the series’s most popular yet, follows wealthy guests and staff members at a wellness resort in Thailand. Among the guests is Chelsea, played by Ms. Wood, a young romantic British woman who is dating an enigmatic older American.

Ms. Wood has been celebrated for her natural smile, especially at a time when many celebrities are opting for veneers to achieve “perfect” teeth. But in a recent interview with GQ magazine, she said that the news media’s focus on her appearance in coverage of the most recent season of “The White Lotus” had made her feel uncomfortable, even if the attention was intended to be positive.

“It makes me really happy that it’s symbolizing rebellion and freedom, but there’s a limit,” she told the magazine. “The whole conversation is just about my teeth, and it makes me a bit sad because I’m not getting to talk about my work.”

“I don’t know if it was a man would we be talking about it this much?” she added.