No sound! Do I need to replace my Left I/O board?

About a year or so ago I dropped my MacbookPro2,2. There is a huge dent in the bottom of the case, as if it fell on a rock or sharp point, which caused the LCD panel to be severely shattered, and my sound to die. I've been using it as a desktop with external LCD & USB sound card, but am thinking of giving it a bit of a repair so I can use it as a media center, so sound is very important.

The sound doesn't work at all; no speakers, no headphone, no digital-out optical, etc. The dent is close to the left hand side of the machine, so I'm hoping only the Left I/O board was damaged in the process. Two questions:

1. Are these symptoms common to Left I/O board failure?

2. And are all audio related circuits on the Left I/O board alone and not on the logic board?

Thanks guys