The midfielder's first half goal was enough to seal victory and a fourth consecutive league title
The Chile midfielder was left unmarked to head home after 32 minutes at the Stadio Luigi Ferraris and that was enough to continue Juve's domestic dominance.
Massimiliano Allegri's side now head into Tuesday's Champions League semi-final against Real Madrid with a historic treble in their sights, having already secured their place in the Coppa Italia final.
Sampdoria made a confident start to the match, with Pedro Obiang sending a blistering strike narrowly wide from the edge of the area.
Juve settled as Stefano Sturaro bustled into the box and saw an effort charged down by Matias Silvestre in the 19th minute, while Fernando Llorente blazed over on the volley before Luis Muriel failed to turn home Samuel Eto'o's cross on the break.
Vidal engineered space for a tamely hit drive in the 25th minute, but he made no mistake when the chance arrived to break the deadlock, heading Stephan Lichtsteiner's left-footed cross back across goal and in off the upright.
The hosts were forced into an early change as Vasco Regini replaced fellow left-back Djamel Mesbah, although they could have been level two minutes before the break.
The lively Muriel slid a pass through for Roberto Soriano to break into the Juventus box, but the midfielder's attempt squirmed wide of the far post - too far ahead of the on-rushing Eto'o.
Sampdoria goalkeeper Emiliano Viviano then produced a save of the highest order to keep Tevez's low strike out of the bottom corner after 58 minutes.
Juventus defender Leonardo Bonucci made a vital last-ditch challenge to thwart Gonzalo Bergessio at the other end, but it was a rare moment of encouragement for Sinisa Mihajlovic's team.
Viviano kept out skidding low shots from Tevez and Claudio Marchisio but it mattered little as Allegri's side saw the game out with ease to clinch yet another league title.