Does My dentist says the tooth will have to be extracted have an abstract noun?

No, the only nouns in the sentence are concrete nouns:

• dentist, a Word for a physical person
• tooth, a Word for a physical thing

An abstract noun is a Word for something that can't be experienced by any of the five physical senses; something that can't be seen, heard, smelled, tasted, or touched. An abstract noun is a Word for something that is known, learned, thought, understood, or felt emotionally.