Final answer:
Elie might think the dentist isn't an actual dentist because McTeague lacked formal dental education, used primitive methods, and demonstrated limited intellectual capabilities.
Step-by-step explanation:
In the texts provided, there are indications that McTeague may not be a formally trained dentist, which can lead to the suspicion that he is not an actual dentist. He started his Dental Parlors after receiving an inheritance from his mother's death, suggesting he did not go through formal dental education but used the money to establish his practice.
Furthermore, the description of McTeague's approach to dentistry, such as extracting teeth with his thumb and finger due to his physical strength, conveys a rudimentary method that lacks professional finesse.
There are also references to McTeague's limited intellect and animal-like characteristics, which further distances him from the professional and intellectual image of a dentist.