This is the 12057th most frequent Russian word.
зубов
"Зубов" is the genitive plural form of "зуб," meaning "of teeth" in English.
In this sentence, 'зубов' is the plural genitive form of 'зуб' (tooth), indicating possession or relation to teeth.
Малыш плакал из-за прорезывания зубов.
The baby cried due to teething.
Here, 'зубов' is used to denote all the teeth in the plural genitive case, related to the necessity of taking an X-ray.
Стоматолог сказал, что нужно сделать снимок всех зубов.
The dentist said that an X-ray of all the teeth is needed.
In this instance, 'зубов' indicates the purpose of the toothpaste—it's for cleaning teeth—again in the plural genitive form.