I am undergoing oral surgery for the removal if a cyst in the roof of my mouth slightly above my front teeth. what are the possible causes. no pain, ?

Numerous casuses: And most are not painful. Most common is a dental abscess from a tooth with a necrotic pulp ("dead nerve"). Other sources can be dental ("supernumerary or extra" teeth), developmental--nerve cells trapped between the "joints" of the bones of the mouth, for example, or neoplastic (pre- or cancerous). It is important that your surgeon submit the tissues to an oral pathologist for microscopic eval.

Many possibilities: The cyst may be caused by several factors. It can come from a "dead" tooth, from the tissue around the root of the tooth, from other tissue near the tooth, etc. The biopsy will give you the answer you are looking for and if any other treatment will be needed.

Possible Causes: There are a number of possible causes including problems directly associated with teeth as well as cysts that are not associated with teeth. In the midline of the anterior maxilla behind the two central incisors, one possibility is an incisive canal cyst or nasopalatine cyst that are benign and often without pain.

Developmental cyst: This sounds like it could be a developmental cyst such as a nasopalatine cyst. It typically does not cause pain unless it becomes secondarily infected.