Minimally invasive surgery is defined as the discipline in which operative procedures are performed in novel ways to diminish the sequelae of standard surgical dissections. The goals of minimally invasive surgery are to reduce tissue trauma and to minimize bleeding, edema, and injury, thereby improving the rate and quality of healing. In orthognathic surgery, there are two minimally invasive techniques that can be used separately or in combination: (1) endoscopic exposure and (2) distraction osteogenesis. This article describes the historical developments of the fields of orthognathic surgery and minimally invasive surgery, as well as the integration of the two disciplines. Indications, techniques, and the most current outcome data for specific minimally invasive orthognathic surgical procedures are presented.

To determine if automated continuous distraction osteogenesis (DO) at rates faster than 1 mm/day results in bone formation by clinical and radiographic criteria, in a minipig model. An automated, continuous, curvilinear distraction device was placed across a mandibular osteotomy in 10 minipigs. After 12 mm of distraction and 24 days of fixation, the animals were sacrificed and bone healing was evaluated. The continuous distraction rates were 1.5 mm/day (n = 5) and 3 mm/day (n = 5). A semiquantitative scale was used to assess the ex vivo clinical appearance of the distraction gap (3 = osteotomy not visible; 2 = 50% visible; 0 = 100% visible), stability (3 = no mobility; 2 and 1 = mobility in 1 plane or 2 planes, respectively; 0 = mobility in 3 planes), and radiographic density (4 = 100% of gap opaque; 3 = >75%; 2 = 50% to 75%; 1 = <50%; 0 = radiolucent). Groups of 4 minipigs distracted discontinuously at 1, 2, and 4 mm/day served as controls. Automated, continuous DO at 1.5-mm/day and 3-mm/day had similar bone formation compared to discontinuous DO at 1-mm/day. The continuous DO 1.5-mm/day group had significantly higher scores for appearance and radiographic density compared with the discontinuous 4-mm/day group. The continuous DO 3-mm/day group had significantly higher scores for appearance and radiographic density compared with the discontinuous 4-mm/day group and greater stability compared with the discontinuous 2- and 4-mm/day groups. Results of this preliminary study indicate that continuous DO at rates of 1.5 and 3.0 mm/day produces better bone formation compared with discontinuous DO at rates faster than 1 mm/day.