Yes, all kids are different and the guidelines for tooth eruption are really just averages. DD is 16 months and has all her teeth bar the last set of molars (which are coming through now).
The only time I've heard of a problem is if the baby is born with a tooth (unusual but not unheard of - I think Louis the IVX had one when he was born). My brother had this and my mom couldn't breastfeed him because of it (really because she had NO support from anyone to get past it - either get the tooth removed or come up with different ways to get around it).
Lisa - mama to Eleanor Rose 01/08 and Saoirse Lily 09/10