The Bruins scored on four power plays in a 10-minute span of the second period and extended the Pittsburgh Penguins' longest winless streak at the start of a season with a 6-3 victory.
With tighter enforcement against holding and interfering, the Penguins were called for 14 penalties and the Bruins 10.
"I think you're going to see that all year," Thornton said after setting an aggressive tone for Boston and scoring his first two goals of the season with two assists. "You definitely have to capitalize when you get those opportunities."
Dave Scatchard scored his first two goals as a Bruin, and Sergei Samsonov and Glen Murray had one each to help Boston snap a three-game losing streak. Three goals came on power plays sparked by constant movement that forced the Penguins to grab players.
"We're the ones that are going to have to find a way to play a disciplined games," Pittsburgh coach Ed Olczyk said.
Former Bruins defenseman Sergei Gonchar tied the game 1-1 at 18:36 of the first period, but the Penguins fell to 0-4-4 after Boston had three two-man advantage opportunities in the second. Before this year, Pittsburgh's longest season-opening winless streak was six games when it went 0-3-3 in 1969-70.
"I just want to win," said Penguins rookie Sidney Crosby, who had two assists and has points in seven of his eight games. "Team points is what matters."
The NHL record for most power-play goals in one period is six set by Washington in a 10-2 win over Toronto on March 13, 1987, and the Bruins' record is five in an 8-0 win at Minnesota on Jan. 4, 1975, according to the Elias Sports Bureau.
"Your special teams better be good because that could be the difference between a lot of wins and a lot of losses," said Scatchard, who signed as a free agent after spending four full seasons and part of a fifth with the New York Islanders.
Boston had just eight power-play goals in its other eight games this season but outshot Pittsburgh 47-21.
Crosby, the first pick in this year's draft, assisted on goals by Ryan Malone and Brooks Orpik in the third period after Boston had taken a 5-1 lead. He also missed an excellent chance 1:33 into the third period when he hit the left post on a breakaway.
Thornton, playing his second game after missing three with a back strain, began the night with six assists and was a physical presence near the net.
"He was our leader just by his actions," Bruins coach Mike Sullivan said. "He's trying to make a concerted effort to be a scoring threat himself."
Scatchard gave Boston a 1-0 lead at 6:50 of the first period before Gonchar tied it on a power play.
Then Scatchard gave the Bruins the lead for good with a power-play goal 4:46 into the second. Murray passed from the left circle across to Thornton who fed Scatchard in the slot for a five-foot forehand past goaltender Jocelyn Thibault.
"It's frustrating," Thibault said. "When you're playing 5-on-3, it's tough."
Samsonov got his fourth goal of the season while the Bruins had a two-man advantage before Thornton scored with a one-man advantage and Murray got his fifth goal while Boston had two extra skaters. The four goals came in a stretch of 9:08 and made it 5-1.
After the goals by Malone and Orpik, Thornton scored with 5:20 left on an pass from Travis Green.
- The first of Crosby's two NHL goals came Oct. 8 against goaltender Hannu Toivonen in a 7-6 Boston win.
- Pittsburgh has led in only one of its eight games, in the Oct. 8 contest against the Bruins.
- Before the game Boston's Brian Leetch received the NHL Milestone Award after becoming the seventh NHL defenseman to score 1,000 points. He reached it last Tuesday with a goal and an assist in a 4-3 loss at Montreal.