Should an ovarian dermoid be removed by laparoscopy or by minilaparotomy?

Depends on size: The surgical approach would be dictated by the size of the cyst and the skill of the surgeon. Wish you good health!

Depends entirely: on size and whether or not your gyn has any suspicion of malignancy. If you are unsure, you should get another opinion, if there is no urgency to the operation.

Lapaotomy: Tumor with, at times, weird malignant potential deserves a good, hands on abdominal exploration.