It was shaping up to be a historic day for Massachusetts dogs the state over Sunday as hundreds turned out to get their teeth brushed at once and break a Guinness World Record.

Armed with special finger brushes and hundreds of tubes of “poultry flavor” toothpaste, the pooches’ owners scrubbed their K-9’s chompers simultaneously. The old record for doing so was 268. No word was available yet on whether festival-goers bested it

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The event was the main attraction at the sixth-annual Somerville Dog Festival at Trum Field, a free annual gathering run by the Somerville Foundation for Animals that spreads awareness about dog health raises money for local pooch-related charities.

The brush-off doubled as education for owners, said Marjie Alonso, a festival organizer and record attempt emcee. 

“Everybody hates brushing their dog’s teeth,” Alonso told Metro.

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But they should be doing it, she said - once a day, because crummy teeth can lead to health issues in dogs.

“We thought it would be fun to help people do this,” she said. “Give them a sample and show them how to start, in a friendly, light way.”

Before the attempt started, Stephanie Birkhimer of Burlington was prepping 5-year-old Kermit, by letting the excited corgi Lab mix lick some samples of the chicken-flavor cleaning goop.

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“He likes to be included in everything,” Birkhimer told Metro.

The meat paste is key when it comes to brushing a dog’s teeth, said Karina Mroczko, owner of a 1-year-old mini golden doodle named Freddy, who was also getting ready to take part.

“He actually has this one in a full-size from his vet and he loves it,” Mroczko said. “He just loves licking it, and that’s when I get the chance to put my finger in there.”

Marilyn Gonzalez said she hadn’t been brushing her three dogs’ teeth, but was inspired by the record attempt to start.

“They liked it!” Gonzalez said of the pups – pugs Roger and Spanky, and Wonton, a Pekingese. “I’m definitely going to start [brushing].”

A pair of comedians warmed up the crowd before the attempt: “I’ve heard of a rough crowd, but this is ridiculous,” said stand-up Casey Malone. “I’ve never seen a crowd play dead before.”

Festival organizer Kelsey Roth filmed the action from an adjacent set of bleachers, overlooking a set of fenced-in corrals manned by dog experts and swarmed with volunteers counting pups with clickers and keeping track of entrants’ names on clipboards. The fact-checkers at Guinness headquarters in London would later approve the attempt, sifting through the array of evidence and studying the footage, Roth said.

“We didn’t realize how involved it would be,” Roth told Metro, but “it’s been great for the festival, it’s gotten us a lot of attention and at the end of the day that’s great for dogs and animals.”