Paul Stastny and Sebastian Aho scored the Carolina goals, and Antti Raanta recorded 19 saves.
The Islanders, who began the third with a 3-1 lead, were in a protective mode in the period, producing only five shots on goal.
Hintz has 11 points in the series (four goals, seven assists), surpassing Mike Modano for the most points in a playoff series in team history.
Oilers 6, Kings 3Nick Bjugstad posted his first career two-goal playoff game to pace Edmonton to a victory over visiting Los Angeles, putting the Oilers one win away from claiming their Western Conference first-round playoff series.
Evander Kane, Leon Draisaitl, Brett Kulak and Zach Hyman also scored for the Oilers, who hold a 3-2 lead in the best-of-seven series.