General:
* Facade: A deceptive outward appearance.
* Sham: A false or deceptive act or appearance.
* Deception: The act of misleading or deceiving.
* Disguise: To conceal or change one's appearance.
* Hypocrisy: The practice of claiming to have moral standards or beliefs to which one's own behavior does not conform.
* Show: An outward display of something, often intended to deceive.
* Act: To behave in a way that is not genuine.
More specific:
* Affectation: A deliberate attempt to appear more important, intelligent, or cultured than one actually is.
* Posturing: Behaving in a way that is intended to impress others.
* Feigning: Pretending to have or feel something.
* Masquerade: A public event at which people wear masks and costumes.
The best synonym for "pretense" will depend on the specific context in which it is used.