title: Bioabsorbable ciprofloxacin-containing and plain self-reinforced polylactide-polyglycolide 80/20 screws: pullout strength properties in human cadaver parietal bones.
abstract: The aim of this study was to compare the pullout forces of recently developed bioabsorbable ciprofloxacin-containing and plain self-reinforced polylactide/polyglycolide (SR-PLGA) miniscrews in human cadaver parietal bones. Parietal bone pieces (approximately 6 x 20 cm) were collected from five human male cadavers (44-75 years of age). Fifty plain SR-PLGA 80/20 miniscrews (diameter = 1.5 mm, length = 4.0 mm) and 50 ciprofloxacin-containing SR-PLGA 80/20 miniscrews (diameter = 1.5 mm, length = 4.0 mm) were used in this study. The force needed to pull the screws from human parietal cadaver bones was measured using a tensile strength-testing machine. The screw pullout speed was 10 mm/min. Means and SDs were calculated and analyzed using the Student t test (SPSS version 10.0 for Windows). The pullout forces of the ciprofloxacin-containing and plain miniscrews were 66.8 +/- 4.9 N and 96.3 +/- 9.3 N (significant difference, P < 0.001), respectively. The most common cause of failure was screw-shaft breakage (60% in the case of ciprofloxacin-containing screws and 52% in the case of plain SR-PLGA screws). Scanning electron microscopy showed that the fibrillar strip-like microstructure of plain SR-PLGA miniscrews turns into a coarse, uniaxial, platelet-like morphology in antibiotic SR-PLGA miniscrews as a result of the addition of ciprofloxacin. Ciprofloxacin-containing SR-PLGA screws consequently have a lower pullout strength than corresponding plain conventional SR-PLGA screws. Nevertheless, it is evident that the ciprofloxacin-containing screws can be applied in craniomaxillofacial surgery in nonload-bearing or slightly load-bearing applications.
authors.affiliation: Department of Surgery, Oulu University Hospital, Finland. jtiainen@cc.oulu.fi
authors.forename: Johanna
authors.initials: J
authors.lastname: Tiainen
authors.forename: Minna
authors.initials: M
authors.lastname: Veiranto
authors.forename: Esa
authors.initials: E
authors.lastname: Suokas
authors.forename: Pertti
authors.initials: P
authors.lastname: Törmälä
authors.forename: Timo
authors.initials: T
authors.lastname: Waris
authors.forename: Milomir
authors.initials: M
authors.lastname: Ninkovic
authors.forename: Nureddin
authors.initials: N
authors.lastname: Ashammakhi
mesh_terms: D020341:Absorbable Implants; D000328:Adult; D000368:Aged; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry*; D001863:Bone Screws; D002102:Cadaver; D002939:Ciprofloxacin / Q000008:administration & dosage / Q000737:chemistry*; D016001:Confidence Intervals; D004337:Drug Carriers; D004867:Equipment Design; D004868:Equipment Failure; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry*; D008297:Male; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D008904:Miniaturization; D010294:Parietal Bone / Q000601:surgery*; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000737:chemistry*; D013223:Statistics as Topic; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength; D016474:Weight-Bearing
chemical_list: D000890:Anti-Infective Agents; D001672:Biocompatible Materials; D004337:Drug Carriers; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D002939:Ciprofloxacin