Veterinarian in Frankfurt

Of course anesthesia is always a risk, especially for older animals. But such a procedure is ALWAYS a major stress for an animal without it.  What gets done in the end without putting an animal under is cosmetic rather than a comprehensive cleaning including under the gum line. This fails to get to the riskiest areas for bacterial infection due to tartar build up. And many ailments are linked to bad oral hygine for animals.

In the end one has to decide for themselves - but most vets advise against such methods.

http://avdc.org/AFD/what-is-an-anesthes … -cleaning/https://healthypets.mercola.com/sites/h … aning.aspx

Once cleaned, prevention can lengthen the time until it has to be done again.
If one starts with a kitten they can be conditioned to having their teeth brushed on a regular basis. Questionable if an older cat will put up with this but I guess it depends on their temperament. Often suggested are using a Q-tip or a piece of gauze wrapped around a finger with special toothpaste sold for cats.

There are also supplements that should help prevent plaque buildup sold as gels or a liquid to be added to their water. Not sure how effective or possibly toxic they might be.