Does a dermoid ovarian cyst always include hair, teeth, skin etc? just had one removed and doc said it needed to come out, why would that be?

Usually: Dermoid cysts contain mature tissues and include one or more of those tissues but not all are always present. It needs to be removed because it will not go away on it's own, could possibly grow larger or even twist upon itself resulting in the need for emergency surgery. If these cysts rupture and spill their contents into the abdomen, peritonitismay develop.

Dermoid: Cysts are also known as teratoma cysts. They have mature skin tissue(hair, teeth, sweat glands..) and are almost always benign. Don't stress it they are removed to ensure that they are benign;think biopsy.

Dermoid cyst: Although almost always benign they can present problems either esthetically or can put pressure on or grow into other vital tissues and compromise their function which would be reason for removal.