title: Classification of midpalatal suture opening after surgically assisted rapid maxillary expansion using computed tomography.
abstract: OBJECTIVE
  The aim of this study was to classify the opening of the midpalatal suture (MPS) after surgically assisted rapid maxillary expansion (SARME) with disjunction of the pterygomaxillary suture through computed tomography (CT) analysis.
  
  
  METHODS
  Seventy adults with bilateral transverse deficiency of the maxilla underwent SARME with pterygomaxillary disjunction. Seventy tomographies were performed before the surgery and 70 were performed after the final activation. The Hass appliance was used in 29 patients and Hyrax in 41 patients. The MPS opening was classified into 2 types: type I, total MPS opening from the anterior nasal spine to the posterior nasal spine, and type II, total MPS opening from the anterior nasal spine to the transverse palatine suture, with partial or nonexistent opening posterior to transverse palatine suture.
  
  
  RESULTS
  Type I opening was observed in 22 patients (31.5%), and type II opening in 48 patients (68.5%). In 5 cases, the opening posterior to the transverse palatine suture was paramedian.
  
  
  CONCLUSIONS
  Computed tomography allows the evaluation and classification of midpalatal suture openings after SARME with pterygomaxillary disjunction in type I (total) and type II (partial) MPS openings.
authors.affiliation: Division of Plastic Surgery, Federal University of Sao Paulo, São Paulo, Brazil. maxdp@terra.com.br
authors.forename: Max Domingues
authors.initials: MD
authors.lastname: Pereira
authors.forename: Gabriela Pereira Ribeiro
authors.initials: GP
authors.lastname: Prado
authors.forename: Meire Maman Fracher
authors.initials: MM
authors.lastname: Abramoff
authors.forename: Antonio Carlos
authors.initials: AC
authors.lastname: Aloise
authors.forename: Lydia
authors.initials: L
authors.lastname: Masako Ferreira
mesh_terms: D000293:Adolescent; D000328:Adult; D003393:Cranial Sutures / Q000000981:diagnostic imaging* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008437:Maxilla / Q000002:abnormalities / Q000601:surgery; D008875:Middle Aged; D009295:Nasal Bone / Q000000981:diagnostic imaging / Q000601:surgery; D016382:Orthodontic Appliance Design; D018704:Orthodontic Retainers; D019340:Osteotomy, Le Fort / Q000145:classification / Q000379:methods*; D010155:Palatal Expansion Technique / Q000295:instrumentation; D010159:Palate / Q000000981:diagnostic imaging* / Q000601:surgery; D012189:Retrospective Studies; D013100:Sphenoid Bone / Q000000981:diagnostic imaging / Q000601:surgery; D036542:Tomography, Spiral Computed; D055815:Young Adult