Neither is normal, and neither is healthy.
Imagine, again, that you are wearing shoes every day that are too small for your feet. Your toes would be scrunched up inside them and they would very quickly get achy. Over years of wearing those too-small shoes, your toes would have a much higher risk of developing early arthritis from the unnatural pressure on them.
Our pets have the same risk of developing early arthritis from nails that are continually too long. Dog/cat nails that are at a healthy length should never be touching the ground when they are standing still. That way, their toes are resting in their natural positions.
In my 18+ years of experience with clipping nails, I've found that monthly trimming does well to maintain nail length, wherever it's at...whether its a good length or still too long.
If you want to shrink the nails back to a shorter, healthier length, then nail trimming must be done weekly or every other week for a couple of months to clip the nails faster than they are growing. Any time frame past monthly, and the nails will always grow faster than they can be clipped.
Using a rotary tool to grind the nails helps tremendously in speeding up the process of shrinking the nails and keeping them short. Not all dogs tolerate the noise or vibration, but it is definitely a huge help, if they allow it. Nail length maintenance can still be reasonably kept with just clipping, if it's done right.
Cats do not ever get their nails ground...just clipped.
See the FAQs page for even more information on nail care.
