One-year postoperative stability of LeFort I osteotomies with biodegradable fixation: a retrospective analysis of skeletal relapse.
BACKGROUND
The purpose of this retrospective analysis was to determine the magnitude of postoperative skeletal relapse of a maxillary LeFort I osteotomy procedure performed with fixation plates and screws composed of a biodegradable copolymer (poly-L lactic and poly-L glycolic acid).


METHODS
Twenty-three consecutively treated subjects, aged 19 to 39, were diagnosed with excess vertical maxillary height or anteroposterior maxillary deficiency and treated with LeFort I impaction or advancement osteotomies. Lateral cephalometric radiographs were measured and compared for the absolute magnitude of skeletal relapse from pretreatment to immediately postoperative to 1 year after surgery.


RESULTS
Correlation analysis determined that a positive relationship existed between the magnitude of the surgical movement and the magnitude of postoperative relapse. The greatest relapse for any subject in any direction was 0.940 mm (anterior nasal spine to nasion-perpendicular). The greatest average relapses were 0.249 mm horizontally (anterior nasal spine to Frankfort horizontal) and 0.141 mm vertically (M-point Frankfort horizontal).


CONCLUSIONS
The most significant contribution of this study to surgical stability literature is reporting the absolute magnitudes of postoperative relapse over a 1-year period of observation. Consistent with previously published reports on postoperative stability, greater magnitudes of relapse were noted for larger surgical movements, yet the absolute values of postoperative relapse with biodegradable copolymers was clinically negligible. Biodegradable copolymers can provide excellent postoperative stability for superior and anterior maxillary surgical repositioning that appears to rival published stability measurements for rigid internal metallic fixation.
Kiely
Kevin Daniel
KD
South County Hospital, Wakefield, RI, USA.
Wendfeldt
Kyle Stewart
KS
Johnson
Baxter Edwin
BE
Haskell
Bruce Steven
BS
Edwards
Richard C
RC
D020341:Absorbable Implants; D000328:Adult; D001672:Biocompatible Materials; D001860:Bone Plates; D001863:Bone Screws; D002508:Cephalometry / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D019248:Jaw Fixation Techniques / Q000295:instrumentation*; D019344:Lactic Acid; D008297:Male; D008310:Malocclusion / Q000601:surgery*; D008437:Maxilla / Q000002:abnormalities / Q000601:surgery*; D019340:Osteotomy, Le Fort; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D011184:Postoperative Period; D012008:Recurrence; D012189:Retrospective Studies
D001672:Biocompatible Materials; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid