The incidence of deformities is differing from one population to another. Nevertheless, the rates reported are considerably high. Correction of deformities usually takes place by means of orthognatic surgery, orthodontic treatment or a combination of these procedures. The aim of this research was to assess the prevalence of complications following orthognatic surgical procedures in patients who had undergone this procedure.Patients were selected from those referred to Taleghani Hospital during 1993 to 1997. An existing data analysis was performed by looking up the patients case notes. Results indicated that: from the total of 101 patients, 16.9 percent were suffering from nerve injury with 4.9 percent suffering from bone segment fracture.

Medical science experts have reached scientific and technological improvements in recent decades and have turned surgery into a routine treatment by controlling its complications. Cumulative changes in surgery resulted in decreased pain and discomfort and controlled complications. The developmental path and changes have resulted in endoscopic with minimal invasive surgery (MIS) in which only few small incisions are made on the body and surgery is done through video control which otherwise required more and larger incision with more complication. But this method with all the usefulness has some problems such as discrepancy between surgeon's eye and hand, indirect and two dimensional vision, limited degree of freedom of instruments and surgeon's fatigue. In addition this type of surgery needs complete education and skill. The sum of these factors limits the use of MIS. In order to overcome these problems, robotic surgery m MIS, a few small incisions are made and surgery method is invented. In this method like n is able to perform the surgery from a distance by a three dimension vision by controlling the arms of robots which are similar to the movements of human and are placed around the table of surgery. Despite all the benefits of this method, its high cost limits its use. Although it's hopeful that with the improvements of this method and its usefulness, the costs will decrease.

Day surgery (also called ambulatory or outpatient surgery), the practice of performing surgery without an overnight hospital stay, is not new- indeed it can trace its origins back to the early 1900s (1, 2)- but it only really became popular from about the 1980s. North America, the United Kingdom and Northern Europe were amongst some of the earliest advocates, but the practice has since spread far wider.Experience from North America suggests that 70- 80% of all elective surgeries may be possible on a day case basis and the United Kingdom is rapidly approaching these levels.