A simple extraction is one in which the dentist can remove the tooth simply by loosening the gums around it, grasping the crown above the gum line, then moving it side to side until it loosens from the bone. Teeth are normally held into the bone by a thin sheathe of soft tissue that separates it from the bone like a sock separates a foot from a shoe. This sheathe is called the periodontal ligament, and it is this structure which ultimately enables the dentist to rmove the tooth. The key to simple extractions is to rock the tooth side to side slowly enlarging the socket in the bone while at the same time breaking the ligament which binds the tooth in the socket.
Unfortunately, not all extractions can be done by simply grasping the tooth with forceps and rocking it out. What if there is nothing left above the gum line to grasp or if the crown breaks off leaving the roots still in the bone? These things can and do happen, and any dentist that extracts teeth will have to deal with them routinely. In these cases, it becomes necessary to surgically remove the tooth. On single rooted teeth a small flap will be raised for better visualization. A small amount of bone will be gently removed to access more solid tooth structure. The tooth will then be removed like a simple extraction. In the case of mulitple rooted teeth, the roots are separated so they can be removed individually. If a flap is needed, the dentist will place sutures so healing can proceed normally.