Most babies start to get teeth when they are around 4-6 months of age. There are some extreme cases on both ends of the spectrum, though. Some freaky kids are born with teeth (I'm glad I'm not their mother!), and it's considered to still be in the "normal" range if a baby doesn't get any teeth until they are 18 months old. Once your baby is past the "normal" range and still doesn't have any teeth, your pediatrician will probably push you to get your baby's mouth X-rayed, but a pediatric orthodontist will tell you that there's no need to do that, since there's nothing they can do until the child is 3 years old. Pediatricians tend to want to over-do and over-medicate things sometimes. As parents, we listen intently to our pediatrician, and then go home and ask the google for more advice. Some times we even use our own common sense. It's worked out splendidly so far.
I know so much about baby teeth because all of our kids were late in getting theirs. The Girl got her first tooth right around 13 months of age, the Boy got his first at 13 and a half months, and the Baby is hurtling towards 16 months, and there's not a sign of a tooth anywhere in that kitten ball-sized head of hers. It's quite the strange phenomenon.
Thankfully, the lack of teeth hasn't negatively affected any of our kids. We started them all on solid foods (actual solid foods, not pureed goop) at the age of 6 months, and they all took to it even though there weren't any teeth. Have you ever been bitten by a baby without teeth? If you have, you know that their gums are as hard as concrete. They can chew their food as well without teeth as they can with. So, soon, our kids were all eating pretty much any food the Wife and I were eating - chicken, steak, pork chops, broccoli, and the list goes on and on.
I mentioned chicken first in that list for two reasons. For one, we eat a lot of chicken in our house, so it was the first thing to come to mind. Secondly, it is ripe in my memory because the Baby, despite her lack of teeth, is ravenous about chicken legs. She actively seeks out chicken legs, whether they have any meat left on them or not. Like a toothless hyena, she can rip all the meat off of a leg bone, and then she sucks every last bit of juice, or whatever you call it, out of all the nooks and crannies. It's something to behold, I tell you what. When she's done, she's pretty much covered in chicken stuff that Daddy or Mommy have to clean up, but her big toothless grin makes it all worth while.
If you ever get stuck babysitting the Baby, just give her a chicken leg to gnaw on. She'll be fixated on it for hours. It'll be the easiest $2 you ever made!