The pair, who train at the Ice Academy of Montreal with many of the top-flight couples, were just 0.51 points behind the sixth place couple, former GB ice dancer Olivia Smart and partner Adrian Diaz, who skate for Spain.
Winter Olympics gold medallists Gabriella Papadakis and Guillaume Cizeron were top after the free programme, with US skaters Madison Hubbell and Zacahary Donohue just under three points behind them with 89.72 points. Fellow Americans Madison Chock and Evan Bates, who beat Hubbell and Donohue in the US national championships, scored 87.51 in third place.
Two Russian couples usually in the top five – Nikita Katsalapov and Victoria Sinitsina and Ivan Bukin and Alexandra Stepanova – have been banned from skating in this year’s world championships due to Russia’s invasion of Ukraine.
Gibson, who finished in seventh place at last year’s world championships, told The Scotsman: “We were so happy with our skate and performance. We really felt determined out there and enjoyed each second.”
The start of the ice dance competition comes as British pair skaters Zoe Jones and Christopher Boyardji received their best-ever ranking in a major championships after finished tenth after the free skate final.
Jones, 42, who is the oldest skater in the competition, where she first appeared as a singles competitor in 1997, announced that the pair would retire after this competition.
Jones said: "This is my partner's decision. Christopher wants to develop as a coach. We train kids together at the Swindon skating rink, he also has his own elite skating school and another business that he is trying to build from scratch. Plus, Christopher has applied to become a technician.
"At 42, I would still ride, to be honest. But we are a couple, and I don’t have the right to keep a person if he is tired of the sport."
Alexa Knierim and Brandon Frazier became the first American pair to win a world figure skating title since 1979.
Knierim and Frazier posted the highest scores in the short program and free skate to win by 21.54 points over Japanese pair Riku Miura and Ryuichi Kihara. However, teammates Ashley Cain-Gribble and Timothy LeDuc, who were in second place after the short programme on Wednesday, were forced to with draw after Cain-Griblle was injured on a fall from a triple salchow. Medics were called onto the ice and she was later taken to hospital. Canadian duo Vanessa James and Eric Radford came in third.
Dundee skater Natasha McKay, who was lying in 24th place in the women’s competition after a clean performance on Wednesday, scored 159.27 overall, rising a place to 23rd.
She said: “I’m really happy with that. To end the season with two solid skates is a dream come true. I didn’t have the best of skates at the Olympics, so this was something of a redemption.”
Kaori Sakamoto from Japan won the gold medal in the women's competition, with Belgium's Loena Hendricks in second place and US skater Alysa Liu in third.