title: Effect of the angle of the screw on the stability of the mandibular sagittal split ramus osteotomy: a study in sheep mandibles.
abstract: We compared the biomechanical stability of 60 degrees and 90 degrees angles for insertion of screws for fixation of sagittal split ramus osteotomies (SSROs) in 10 sheep mandibles in vitro. After 5 mm advancements, the osteotomies were fixed with screws 2 mm in diameter inserted with a torque control screwdriver at either 60 degrees or 90 degrees to the long axis of bone, in a matched pair experimental design. All specimens were then loaded in a physiological manner and the load-displacement of the osteotomies was recorded. Data for resistance to movement were compared by a paired t -test. The mean (SD) resistance to movement for the 60 degrees and 90 degrees screw insertions was 63.4 (27.7) N/mm and 59 (22.3) N/mm respectively. There was no significant difference between the groups. This correlates with clinical findings.
authors: Beth Israel Medical Centre, New York, USA. suckan@yahoo.com
authors: S
authors: S
authors: Uckan
authors: A
authors: A
authors: Schwimmer
authors: F
authors: F
authors: Kummer
authors: A M
authors: AM
authors: Greenberg
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D001863:Bone Screws; D003799:Dental Stress Analysis; D019248:Jaw Fixation Techniques / Q000295:instrumentation*; D008334:Mandible / Q000601:surgery*; D010027:Osteotomy / Q000295:instrumentation* / Q000379:methods; D012756:Sheep