Cariologie

In this episode of Romanian Who wants to be a millionaire?, one of the questions is about the scope of study of cariologie. There were, as always, four choices as answers: cell nuclei; dermis and epidermis; hair and nails; and enamel and dentine. The contestant decided to walk away as she didn't know the answer, but at the host's request, said she would have chosen enamel and dentine. The correct answer was given as cell nuclei. As the word reminded me a lot of caries/tooth decay, I went on a quest for its meaning. This Romanian dictionary confirms it means a science that studies the structure and functions of the cell nucleus and gives French caryologie as its source. French caryologie indeed means that, but on the Internet you also find Romanian professionals in the area of cariologie who describe it as the part of medicine that treats caries.

The interesting thing is that I've found both karyology and cariology in English, the first deals with cell nuclei, the second with caries, but both would merge to the same letters, c and i, in languages that don't use k and y, which is the case of Romanian (among others). Can the same Romanian word refer to two distinct scientific specialties, or is there a real difference between studying only caries and studying enamel and dentine, which would then exclude letter D as an answer? At least the contestant walked away and wasn't harmed by choosing any alternative.