Luiz will leave the club at the end of the campaign and following Arsenal's 2-0 victory over Brighton on the final day of the Premier League season at the Emirates, he was mobbed by his teammates and the celebrations resulted in Gabriel losing a tooth.
The 23-year-old was seen looking around the pitch looking for his missing tooth while his teammates stood and laughed at the situation.
While players and managers were conducting their postmatch interviews, members from the Arsenal coaching staff were also seen searching for the lost tooth near the centre of the ptich.
When asked about the incident, Arsenal boss Mikel Arteta laughed and told reporters: "You guys are here and very close to him so you can help him."
Later on Sunday, Gabriel gave an update on the search and posted on his Instagram story: "Don't worry guys, I found my tooth."
The Brazil international has been one of the positives for Arsenal this season who finished eighth in the table and miss out on European football for the first time in 25 years.