OBJECTIVE: To determine the optimal fixation technique for @entity1641 interdental space @entity174 by evaluating the biomechanical characteristics of 4 fixation techniques. STUDY DESIGN: In vitro randomized block design. SAMPLE POPULATION: Twenty-seven adult @entity1641 mandibles. METHODS: Mandibles with interdental osteotomies were randomly divided into 4 fixation groups (n = 6/group). Fixation techniques were the following: (1) dynamic compression plates ( @entity1298 ), (2) external fixator (EF), (3) external fixator with interdental wires (EFW), and (4) intraoral splint with interdental wires (ISW). Three intact (nonosteotomized) mandibles were tested as controls. Mandibles were subjected to monotonic cantilever bending until failure. Angular displacement data (radians) were derived from continuously recorded gap width measurements provided by extensometers placed across the osteotomy site. Osteotomy gap width data (mm) at 50 and 100 Nm were selected for standardized comparison of gap width before the yield point and failure point, respectively of all constructs tested. Stiffness (Nm/radian), yield strength (Nm), and failure strength (Nm) were determined from bending moment-angular displacement curves and were compared using ANOVA with appropriate post hoc testing when indicated. Radiographs were obtained prefixation, postfixation, and posttesting. RESULTS: Bending stiffness, yield, and ultimate failure loads were greatest for intact mandibles. Among osteotomized mandibles, stiffness was greatest for @entity1298 constructs (P <.05) and was not significantly different among EF, EFW, and ISW constructs. Yield load was greatest for ISW constructs (P <.05) and was not significantly different among @entity1298 and EFW constructs. Yield and ultimate failure loads were @entity2729 at 50 and 100 Nm were greatest for EF constructs (P =.09 and P <.05, respectively). There was no significant difference in failure loads and osteotomy gap widths among @entity1298 , EFW, and ISW constructs (P <.05). Failure occurred through the screw-bone interface ( @entity1298 ), acrylic splint (ISW), acrylic connecting bar and/or pin-bone interface (EF, EFW), and wire loosening (EFW). All 3 intact mandibles fractured through the vertical ramus at its attachment to the testing apparatus. CONCLUSIONS: Among osteotomized mandibles, @entity1298 fixation had the greatest stiffness under monotonic bending to failure; however, the relatively low yield value may predispose it to earlier failure in fatigue testing without supplemental fixation. Techniques using tension-band wiring (EFW and ISW) were similar to @entity1298 constructs in yield, failure, and @entity572 , whereas EF constructs were biomechanically inferior to all other constructs. CLINICAL RELEVANCE: @entity1298 fixation is most likely the most stable form of fixation for comminuted interdental space @entity174 . However, for simple interdental space @entity174 , ISW fixation may provide adequate stability with minimal invasiveness and decreased expense. Tension-band wiring significantly enhances the strength of @entity853 and should be used to augment mandibular fracture repairs.

Fixation technique influences the monotonic properties of XXXX mandibular fracture constructs.

@entity1641 :: ('9796', 'Species') :: ['equine'] @entity174 :: ('MESH:D050723', 'Disease') :: ['fractures'] @entity853 :: ('MESH:D009139', 'Disease') :: ['type II external skeletal fixators'] @entity1298 :: ('CHEBI:60424', 'Chemical') :: ['DCP'] @entity572 :: ('MESH:D006617', 'Disease') :: ['osteotomy displacement'] @entity2729 :: ('MESH:C537241', 'Disease') :: ['lowest (P <.05) and osteotomy gap width']
@entity1641 :: (9796,Species) :: ['equine']
