By George I think of got it!!
Snakes grow partly developed replacement fangs behind the main fangs in a type of sheith. If a main fang is broken or lost then a replacement grows and slides into place between 5-6 days after.
The other teeth in a snakes mouth which are small rows of recurved teeth do not regrow because they have about 6 small rows in the mouth. These teeth help hold the prey in place.
Hope this helped