Ortho Procedures - SARPE -Surgically Assisted Rapid Palatal Expansion

SARPE is an acronym used for Surgically Assisted Rapid Palatal Expansion. It is also sometimes referred to as SARME or Surgically Assisted Rapid Maxillary Expansion. SARPE is an orthodontic technique that is used to expand the maxillary arch. This technique includes treatments from both Oral and Maxillofacial Surgery and Orthodontics. This procedure is usually completed in adult patients with maxillary sutures that are fused and cannot be expanded using other techniques.

History

Orthodontic expansion was first described by Emersen Angell almost 150 years ago. In 1959, Kole was the first person to speak about the procedure of corticotomy in adults who have a maxillary constriction. In 1938, the surgical technique for SARPE was first described by Brown. Steinhauser first described the technique in 1972 which involves the segmental left and right split of the maxilla along with the placement of the graft.

Indications

• Mature skeletal structure or adult patient
• Fused intermaxillary suture
• Transverse maxillary hypoplasia
• Bilateral posterior crossbite
• Prior failure of the use of any other expansion devices
• Dental crowding from the lack of space in the maxilla
• Obstructive sleep apnea

Procedure

SARPE is performed with the goal of addressing the transverse dimension changes in a patient. In some cases, the surgery is followed by Le Fort 1 in a second surgery. This is completed in order to address the vertical and the anterior-posterior changes. Between the two surgeries, the patient's constricted maxillary arch is expanded through the use of rapid maxillary expander device which is placed in the maxilla. During the first surgery, the patient goes through Le Fort fracture of skull without the downfracture of maxilla. This is completed under local anaesthesia and iv sedation or general anesthesia. The oral surgeon will also perform the midpalatal osteotomy in order to allow the break in the inter-maxillary suture. The surgeon, while simultaneously performing the LeFort 1 osteotomy, may separate the pterygoid plates. This separation of the plates is called a Pterygomaxillary disjunction or PMD. Some of the surgeons are more conservative in their approach to separate the pterygoid processes because of the risk of injury to the pterygoid plexus.

Sangsari published a review and a meta-analysis in 2016. The review studied the effects PMD had on the overall outcome of SARPE. From the three different studies which were included in their criteria, the literature was inconclusive regarding the effects PMD had on the outcomes of SARPE. The review also suggested that further controlled trials were required.

Procedure Stability

Chamberland and Profitt published a paper in 2011. The paper evaluated the long and short-term effects of the SARPE procedure. The SARPE procedure was completed with pterygoid plate separation in order to achieve the transverse expansion of the maxilla. The authors observed skeletal changes of approximately 3 to 4mm and these changes were consistent. In a previous study, which was published in 2008, the authors stated about a third of the transverse dental expansion that was obtained with SARPE is lost. The skeletal expansion, however, remains the same. The paper also stated that the post-surgical relapse with SARPE was similar to the changes in dental arch dimensions after non-surgical rapid palatal expansion. The relapse was also quite similar to the dental arch changes found after a segmental maxillary osteotomy which is used for expansion. As a result, the stability of the procedure is not more successful than other expansion techniques.

A study performed by Northway in 1997 stated that the long-term buccogingival expansion was more acceptable in adults who were expanded with surgical augmentation than in those who were expanded orthopedically. One downside of this study is that the measurements were taken on dental models of the patients.

Procedure Disadvantages

• Aesthetic limitations following the expansion with RME
• The post-operative implementation of the palatal expander
• Patient compliance is critical
• Follow-up surgery is common