Alice In Chains - Grind Lyrics Meaning

All I can say at this point, after having read the previous submissions, is that the lines, "Let the sun never blind your eyes/let me sleep so my teeth won't grind/ hear a sound from a voice within"---these lines, I believe, refer to a problem with methamphetamines. I've spent more than my share of time strung out and banging my head against the wall---and losing teeth for grinding down to the gums. Some of the lyrics to this song seem like non-sequiturs. I love Alice, but some of their lyrics just reveal they've never taken English 101.