**4. Indications for SARME**

**2. Correction of transverse discrepancy via orthodontics**

120 A Textbook of Advanced Oral and Maxillofacial Surgery Volume 2

expansion is indicated to release areas of bony resistance in the midface [28].

**3. Surgically Assisted Rapid Maxillary Expansion (SARME)**

have conventionally been grouped into 2 categories:

in a widened transverse dimension, and

**2.** Surgically assisted rapid maxillary expansion (SARME).

of expansion [25-27].

buttresses. [32]

This is successful until the age of approximately 14–15 years depending on the gender of the patient. After this age, orthodontic widening becomes virtually impossible and very painful. In general, it is assumed that closure of the midpalatal suture prevents this type

On the other hand, Mommerts outlined a basic treatment strategy for patients with maxillary constriction, based on age that rapid maxillary expansion should be completed to treat maxillary constriction in patients under the age of 12. From age 14 on, surgically assisted palatal

The areas of resistance to lateral forces in the midface are the pyriform aperture (anterior), the zygomatic buttress (lateral), the pterygoid junction (posterior) and the midpalatal synostosis suture (median). Many surgical interventions and techniques have been developed by the identification of these areas of resistance. Surgery assisted maxillary expansion procedures

**1.** Segmenting the maxilla during a LeFort osteotomy to reposition the individual segments

**Advantages of SARME** over orthodontic therapy and segmental Le Fort procedures include decreased risk of periodontal damage, improved esthetics when smiling, improved nasal air flow, and decreased risk of avascularity. SARME is also a relatively simple procedure and is associated with minimal morbidity. Intraoperative complications are uncommon and there is also less chance of avascularity leading to aseptic necrosis than with segmental Le Fort I procedures. [29, 30] Brown [12] was probably the first who described a technique of SARME with midpalatal splitting. [31] In 1961, Haas described the downward and forward movement of the maxilla that occurs during rapid maxillary expansion because of the location of the craniomaxillofacial sutures. He believed that the hemimaxillas separated from each other develop tipping rather than separating in a parallel fashion due to the strength of the zygomatic

Most methods consider the zygomaticomaxillary junction the major site of resistance and perform a corticotomy through the zygomatic-maxillary buttress from the pyriform rim to the maxillopterygoid junction. The midpalatal suture is historically considered the major place of resistance. The pterygoid plates are also a considerable site of resistance but because of the increased risk of injuring the pterygoid plexus by the osteotomy, some chose not to, without losing much mobility. By not releasing the pterygoid junction, the pattern of opening of the

maxillary halves is more V-shaped with the point of the V located dorsally [33-37].


Several authors have shown that surgically assisted maxillary expansion can be carried out using only sedation and local anesthesia when a more conservative surgical technique is chosen. General anesthesia is preferred for invasive techniques. [48-50] Considering all these surgical techniques and discussions of advantages of one technique to another, most surgeons prefer to perform osteotomies on all four areas of resistance.
