a typical SARPE procedure (now SAMARPE) or less invasive techniques. It has been demonstrated that both posterior expansion at the PNS, as well as expansion of the nasal aperture are critical in treating Obstructive sleep apnea. Surgically Assisted Rapid Palatal Expansion (SARPE) Once a patient reaches maturity (puberty) the palate halves or the Intermaxillary suture fuses together into a single palate tissue. If the patient suffers with a constricted maxillary arch, a palatal expander would need to be used. However, with the matured palate, the palatal expander would need to be surgically inserted onto the mid-palatal suture. Typically, the patient would be under the care of an oral-maxillofacial surgeon and the surgical procedure would commence. The mid-palatal suture is first cut open into two parts. The center of the midpalatal suture is then inserted into the open slit. Once fully inserted, the mid-palatal suture of the patient is then closed by the surgeon. The orthodontist will then finish the procedure by connecting the palatal expanders band rings to the patients maxillary molars. Side-effects of a palatal expansion Trouble with pronunciation - Patients who have expanders may experience extra saliva and lisps (pronouncing the letter s, t, and r blends become very difficult). Pain - Patients may experience pain and headaches while wearing palatal expanders and when the screw is turned. Sores on tongue - This can happen due to contact with the expander's metal bars. Diastema - Space between upper front two teeth Fenestration of buccal bone Compression of periodontal ligament near posterior teeth Extrusion of posterior teeth Increased lingual bone thickness, decreased buccal bone thickness One of the limits of expansion is the zygomatic buttress. It is known that this anatomical bony complex limits the maxillary expansion posteriorly. Maxillary expansion does tend to open up circumaxillary sutures, circumzygomatic sutures, intermaxillary sutures and midpalatal sutures. Expansion also tends to happen more anteriorly than posteriorly. Amount of expansion Each patient presents with different malocclusion and will need different amount of expansion. It is a general rule to expand the maxilla to a point where the lingual cusp of maxillary molar teeth touch the buccal cusp of mandibular molar teeth. Studies done decades ago by Krebs (1964), Stockfisch (1969) and Linder Aronson (1979) showed that about one-third to one-half of the expansion was lost before the expansion was eventually stabilized. History Westcott first reported placing mechanical forces on maxilla in 1859. Emerson