Dear Nazeera,
As I understand from your post you developed
parotitis twice and you were treated by
drainage of the pus.
Well you can avoid it from coming back by maintaining a good
oral hygiene. Get a full mouth oral prophylaxis done by a good
dentist. Ask him to tell you how to maintain the good hygiene. regular brushing atleast twice daily, use of
chlorhexidine mouth wash on regular basis, warm water with a little salt gargle atleast three times a day. all this will help you to maintain a good hygiene and hence prevent recurrent attack of parotitis.
In case the cause is some thing else like a viral infections then it has to treated symptomatically but even in that casse a good oral hygiene is mandatory.
Take care