This was a movie I saw, maybe in the 1980s or early 90s, about a
family with teenage children who move into a home. The house appears
to be alive or cursed and it terrorizes the family, with tree branches
scaring the children at night, and other strange things happening. One
time the teenage son is in the bathroom and his braces grow and nearly
cover him entirely. Eventually the family has enough and drives away
for good at the end. This movie is not The Amytiville Horror, and I
would like to find out what it is...

Hello Simeet20,

The movie you recall is Poltergeist II: The Other Side, (1986) 

Here are some reviews where the braces scene is mentioned.

"Portents of trouble to come include Carol-Anne (Heather O'Rourke)
sketching an evil face, Diane dreaming about zombies dragging her
under the garden, Robbie being cocooned by wire from his braces, and
Carol-Anne's toys coming to life."
http://www.michaeldvd.com.au/Reviews/Reviews.asp?ID=3406

"As for the spooky paranormal encounters, Nelson coughs up a mutated
tequila worm, Robins battles his braces in the bathroom, and Williams
shrieks her way through a couple more corpse scenes. Overall,
"Poltergeist II" is good."
Amazon
http://www.amazon.com/gp/product/B00009PY4G/103-8989118-0440621?v=glance&n=130

"An early scene with Robbie being attacked by his braces nicely taps
into young kids? nightmares about their metal-enhanced teeth, but by
the finale ? in which the pink-swirled netherworld looks like the
inside of a cotton candy cone ? you?ll desperately wish Kane had just
killed the Freelings when he had the chance."
http://www.nickschager.com/nsfp/2004/03/poltergeist_ii_.html


 

Plot Summary for  Poltergeist II: The Other Side (1986)

"The Freeling family move in with Diane's mother in an effort to
escape the trauma and aftermath of Carol Anne's abduction by the
Beast. But the Beast is not to be put off so easily and appears in a
ghostly apparition as the Reverend Kane, a religeous zealot
responsible for the deaths of his many followers. His goal is simple -
he wants the angelic Carol Anne; but the love of her family and the
power of psychic Tangina once again unite, along with an elderly
native American, to fight for her life."
IMDB
http://www.imdb.com/title/tt0091778/plotsummary
 
The DVD is available at Amazon
http://www.amazon.com/gp/product/B00004XOD2/qid=1133387528/sr=1-2/ref=sr_1_2/103-8989118-0440621?s=dvd&v=glance&n=130


Search criteria:
movie haunted house Poltergeist  braces

I hope this helps!

Best regards, 
Bobbie7

Great job...the answer was thorough and excellent.

Thank you for the stars and tip!
--Bobbie7