Ronaldo, who on Wednesday "firmly denied" rape allegations dating back to 2009, effectively put the game beyond Udinese just before half-time and it was plain-sailing from there for Massimiliano Allegri's men.
Juve were dominant right from the start and capitalised when Bentancur and Ronaldo found the net four minutes apart.
The home side did go close on a couple of occasions, though they never looked capable of clawing things back, as Juve preserved their record of being unbeaten away from home in Serie A this calendar year.
Udinese struggled to even get out of their own half in the first period and it was a surprise they kept it 0-0 for as long as they did.
Bentancur eventually broke the deadlock 33 minutes in, rising well to meet Joao Cancelo's glorious cross and head in.
Ronaldo doubled Juve's lead soon after, shooting left-footed across goal and finding the bottom-right corner.
Udinese could have pulled one back just prior to the break, but Antonin Barak's 25-yard strike hit the post.
Kevin Lasagna then went close in the second half, latching on to a free-kick and seeing his goal-bound effort cleared off the line by Emre Can, a half-time replacement for Blaise Matuidi.
Ronaldo could have got himself a second goal 16 minutes from time, but Simone Scuffet made a fine save with his foot to keep the effort out and Juve were unable to add further gloss to the scoreline as a late deflected Cancelo strike hit the crossbar.
Bentancur appeases Allegri
Young Uruguayan midfielder Bentancur spoke midweek about coach Allegri urging him to get forward more often to become a goal threat, and he certainly appears to have learned quickly. The 21-year-old got off the mark for the club with a poacher's goal, nodding in from close range ahead of Ronaldo, but his forays forward did not have a negative impact on his usual style of play, as he battled away and was neat in possession.
Serie A already looking a procession
Eight matches, eight wins and 24 points – it is all looking rather good for Juve in Serie A. At the end of Sunday's action, Juve could potentially be nine points clear at the top. While Napoli have looked well-marshalled under Carlo Ancelotti, they have not shown the same brilliance they did with Maurizio Sarri at the helm last term.
