Fab question! So you are quite right, there are so many different types of cells and they all can live in very different environments. I test my samples on the cells which make and look after your bone as they will be the cells closest to the implants in real life. Lots of work has all been brought together into documents called ‘Standards’ and we also run tests from these which aim to make sure that products are safe for all the cells they could come into contact with for whatever application you use, so it will all have to be really thoroughly tested. I hope this answers your question.