The win was Penrith's sixth in a row, while the Dogs ended the year with four straight losses.
Moses Mbye opened the scoring when he dummied his way through the Panthers' line in the 14th minute.
Penrith had dominated up until that point but from then on the Dogs enjoyed a period of significant ascendancy.
But the only further points they could muster was a penalty goal in the 26th minute.
The Panthers pegged that lead back in the 34th minute when a series of offloads on the Dogs' line and a lovely Nathan Cleary long ball put Dallin Watene-Zelezniak over for a halftime lead of 6-4.
Waqa Blake put Penrith in the lead for the first time three minutes after the break after finishing off a Josh Mansour linebreak.
Things got worse for the Dogs when fullback Brett Morris limped off with a knee injury in the 49th minute.
Peter Wallace finished off a thrilling 50m movement in the 54th minute to stretch Penrith's lead to 16-6 before Josh Morris was controversially disallowed a try.
Morris appeared to ground the ball on the tryline but referee Jared Maxwell ignored the centre's pleas to defer to the bunker.
When Tyrone Peachey dummied three times to cross for Penrith's fourth try in the 62nd minute the game was over as a contest.
A shattered Josh Reynolds was taken off for concussion in the 64th minute and didn't return.
Mansour scored again for Penrith five minutes from time.
Retiring Dogs utility Sam Perrett scored a consolation try with two minutes to go in his final game.
Dogs forward Tony Williams could be in trouble for a second half shoulder charge.
Blake could be in doubt for next week with a shoulder problem.
- AAP
