It’s usually a bad sign to equate a movie with a dental visit, but Hairspray is different. Its mighty precision-tool force is wielded not to fill cavities but cause them with truckloads of sugar. In this case, you definitely won’t mind having all the sucrose shoveled down the throat.

Song for sickly sweet song, Adam Shankman’s film evokes the toe-tapping jump, jive and shout vibe of ’60s pop, draws great performances from John Travolta and Christopher Walken and proves no one’s writing musicals better than Marc Shaiman.

Adapted from John Waters’ 1988 film, Shaiman’s Tony-winning musical from 2002 followed his raucously uproarious song contributions to the 1999 film South Park: Bigger, Longer and Uncut.

Tracy Turnblad (winsome newcomer Nikki Blonsky) is a plus-sized teenager in 1960s Baltimore who rushes home after school with pigtailed pal Penny Pingleton (Amanda Bynes) to dance along with The Corny Collins Show. An underrated comic actor, James Marsden plays Corny with gleaming teeth, but a fading smile for a format that’s stilted in its sameness and segregation.

When a show slot opens, rump-shaking Tracy’s passion to audition is fostered by her joke shop-running dad Wilbur (Christopher Walken) and pooh-pooh’d by her super-sized shut-in mom Edna (Travolta, encased in prosthetic flab, but freed from the shackles of all his star-power expectations).

Much to the chagrin of stick-thin show producer Velma von Tussle (Michelle Pfeiffer, back as a bronzed baddie after a five-year break), Tracy becomes a star. It’s the start of a shimmying revolution that will be televised. Tracy makes moves on dreamboat dance icon Link Larkin (Zac Efron) and befriends Motormouth Maybelle (Queen Latifah) who, with black teen dancers like her son, Seaweed Stubbs (Elijah Kelley), takes over Corny’s show once a month for “Negro Day.”

Sifting through trash like Bringing Down the House and Cheaper by the Dozen 2, there was no reason to think Shankman was capable of such a winning film. After a wobbly, constricted beginning, it bursts with clouds of extra volume and hold during flawless second and third acts. Shankman does much more with the movie presentation than stage left, stage right enhancement.

“Welcome to the ’60s,” “Without Love” and closing number “You Can’t Stop the Beat” explode with grand choreography. And the exuberant “Run and Tell That” should make a star of Elijah Kelley, whose Seaweed Stubbs makes Penny give thought to becoming a “checkerboard chick.”

The showstopper, though, is “Timeless to Me.” This sashaying, soft-shoe husband-and-wife duet from Travolta and Walken is the song-and-dance equivalent of Al Pacino and Robert De Niro sharing a screen, and it’s thankfully much more than just a campy pairing and easy punchlines.

Walken puts a wacky spin on his family man in “Catch Me If You Can” and sells Wilbur’s unwavering commitment to Edna. With darting eyes, pursed lips and furtive hands, Travolta plays Edna with full feminine zeal, never cheaply flopping around cellulite. (His only misstep is a come-and-go mealy-mouthed accent that sounds too much like Dr. Evil.) Mimicking mannerisms works for Travolta, as it’s his best work since channeling Bill Clinton in 1998’s Primary Colors.

Yes, Hairspray takes the still-burning fire of Baltimore’s dicey racial-relations history and reduces it to torched crème brulee, but doesn’t pretend its story is an empty-calorie cure-all. The more subversive elements of Waters’ film have been buried, but Shankman has unearthed the bounciest, bubbliest movie musical of the modern era.