title: A novel designed screw with enhanced stability introduces new way of intermaxillary fixation.
abstract: BACKGROUND
  This article represents new design of a fixation screw-spike screw-for the intermaxillary elastic fixation application after the first surgery in orthognathic surgery. This new type called spike screw is easily placed and provides enough rigidity for the intermaxillary fixation (IMF) with increased stability that was a common problem using screw-type fixation.
  
  
  METHODS
  Spike screw has a unique design: a washer with soldered stainless hook that adds stability and fixation to the screw done by a miniscrew. It increases stability by reducing the high peak stress-often occurs in miniscrew-and obtaining the advantage of miniplate system with miniscrew fixation. It allows noninvasive screw placement unlike miniplate. The 8 spike screws were placed on the posterior lesion to provide secure IMF, and 2 I-type C-tubes were placed on the anterior lesion.
  
  
  RESULTS
  By modifying the length of the hook attached to a washer can accommodate each patient's IMF length variation like a custom-made screw. The stability of the screw was kept well for 6 weeks even with minor gingival irritation in some of the area. This proved that spike screw could be one of the methods for IMF. The closeness of the hook to the teeth eliminated further gingival irritation around the elastic attachment site. Finally, it provided easy manipulation of the hook to change vectors of the elastic force application.
  
  
  CONCLUSIONS
  The novel design of the screw permits easy placement and removal for the IMF. In addition, its advantages include increased stability with unique design, less gingival irritation, and simple vector modification of the IMF elastics by adjusting the hook length and shape.
authors.affiliation: From the *Department of Orthodontics, School of Dentistry, Kyung Hee University; and †Department of Orthodontics, School of Medicine, Ajou University, Suwon, Korea.
authors.forename: Kyung A
authors.initials: KA
authors.lastname: Kim
authors.forename: Hyo-Won
authors.initials: HW
authors.lastname: Ahn
authors.forename: Soon-Yong
authors.initials: SY
authors.lastname: Kwon
authors.forename: Kyung Won
authors.initials: KW
authors.lastname: Seo
authors.forename: Seong-Hun
authors.initials: SH
authors.lastname: Kim
authors.forename: Kyu-Rhim
authors.initials: KR
authors.lastname: Chung
mesh_terms: D001863:Bone Screws; D004867:Equipment Design; D005260:Female; D006801:Humans; D019248:Jaw Fixation Techniques / Q000295:instrumentation*; D024343:Open Bite / Q000601:surgery*; D057909:Orthognathic Surgery / Q000295:instrumentation*; D010027:Osteotomy / Q000295:instrumentation; D011378:Prognathism / Q000601:surgery*; D055815:Young Adult