Answer: No. It isn't an example of ethos.
Explanation:
Ethos refers to an argument that's based on the credibility of the person that's making the argument.
Ethos simply means establishing the authority to speak on a particular object subject. It's the persuasion and the argument whereby the knowledge, good moral character and the credibility of the speaker is shown.
In this case, the example given isn't an example of ethos because dentists in this case is a broad term and therefore does not give credibility from a particular dentist or probably a dental research.
At the beginning of the novel Animal Farm, the animals wanted freedom. They no longer wanted to be slaves to mankind.
By the end of the novel, the animals are no longer slaves to mankind -- now, they are slaves to the pigs. The animals have substituted one master for another and will not get the freedom they once desired.
The pigs went from wanted freedom for all to just wanting freedom for themselves. They are no better than men.
In this way, they have gone against the ideals they professed to hold at the beginning of the novel.
in this order: choose a topic, create a thesis statement, search for supporting content, organize the content into three parts, review and revise the presentation, and practice the presentation in front of family or friends.