grayish spots on front teeth?

my son had this....his tooth turned black, then started to turn back to white, then ended up grey...he had damaged his tooth in a little accident with eli. :) the tooth was actually broken deep inside near the root..and the tooth had to be removed. he was 4 1/2...and after another xray the dentist said we should expect the new tooth at age 7. lol...so i have a toothless wonder....and we are actually waiting on one more tooth....we think he'll have to have that one out too for hte same reason. when i was reading online about this, it appeared to be somewhat common for boys aged 3-4...lol....so, just in case this is what has to happen, know that your child would not be alone in a toothless grin that lasted a LONG time. lol. :)good luck!