Missing incisors

At what age do cats start losing incisors without it necessary being a cause for great concern? Or would it right away be a concern?

I was just checking my boys mouths and realized two out of three have only 5/6 incisors on lower jaw. I have somehow failed to check this before and suspect this has been the case for a long time, at least for Teppo. (His jaw looked like it never had more than 5). I usually concentrate on their back teeth and just take a cursory look at the fangs and maybe the upper little teeth to see the condition of the gums. Those little things are so jammed up together it's hard to even get a count.

Anyway, there is no sign of traumatic injury but should I worry about adding something to their diet? I always ask vet to take an extra look especially at Teppo's teeth because he has quite a lot of tartar and gingivitis. The vet has never been worried and we have never had any 'professional' work done on any of the boys' teeth.

Several of my fosters (former street cats) are missing incisors and according to my vet the main culprit is diet and also pregnancy/nursing in females. As I understand it the reason pregnancy and nursing affects the teeth is because the mom cat loses calcium while pregnant and nursing. Although your boys obviously have not been pregnant the issue may still be lack of calcium in their diet and maybe other issues with the diet. Do they eat dry or canned food? What brand of food do they eat?

Some cats are just prone to gingivitis though. According to my vet the only way to deal with such things is to brush the cats' teeth daily but getting a toothbrush in my cats' mouths and keep it in there for more than a second is nothing that is possible in my household. We have to do our best with dental chews.

I was instantly worried about the diet. Of course they all eat the same diet and one of them has strudy, great looking incisors - and he is my anorexic, healthy eating stick-insect who prefers kibbles (and also chews them).

I feed mixed dry and wet. The main dry is Innova and Innova Lite. I have attempted several others to provide variety but keep coming back because success rate isn't great. Premium Edge was my other choice until constipation issues removed that from the list.

Main wet food is Wellness. I vary that with Merrick but there are only a couple flavors boys like, it's kind of falling out of favour. Teppo has some major weight issues and this summer I have tried MaxCat Lite Gourmet too which he likes. I am not sure that is such a great food but that hardly would have had and effect on the teeth yet.

Also, for snacks I feed Hill's Dental Diet.

I would like to change foods more often to make sure bases are covered but one of my cats has sensitive belly, and one is very picky. Teppo eats nearly everything. He had bad teeth when he came. I seriously suspect he had been fed human food for his first 3 years.

I don't know how many different foods I have tried and boys have refused. Any suggestions for the calcium? All my boys are around 6 years of age btw.