Isaiah Thomas scores 53 in Celtics’ OT win over Wizards

Isaiah Thomas spent four or five hours in the dentist’s chair having work done on the tooth that was knocked out in Game 1, a day after he was in oral surgery for six hours having it repositioned in his mouth.

“The least I can do is go out there and play for her,” Thomas said after scoring 53 points — the second-highest total in Celtics playoff history — to lead Boston to a 129-119 overtime victory over the Washington Wizards.

“I knew once game-time came, my guys would get me going, get me the energy to go out and win a game,” Thomas said, ducking his face into his hands as he mentioned his sister, Chyna, who died in a car crash on the eve of the playoffs.

Fiddling with his new mouth guard throughout the game, Thomas scored 20 points in the fourth quarter and nine in overtime to help the Celtics take a 2-0 lead in the best-of-seven Eastern Conference semifinals.

The 53 points were the most in an NBA playoff game since Allen Iverson scored 55 in 2003, and just one shy of John Havlicek’s franchise postseason record of 54.

Thomas attended his sister’s funeral on Saturday and returned to Boston early Sunday morning, just hours before the Celtics won 123-111 and the diminutive point guard lost a tooth.