title: Biomechanical study of the Delta plate and the TriLock Delta condyle trauma plate.
abstract: OBJECTIVE
  The aim of this study was to evaluate in mandibular condylar process fractures the biomechanical stability of osteosynthesis using the Delta plate and the TriLock Delta condyle trauma plate and to compare these with 2 4-hole miniplates.
  
  
  METHODS
  The condyles of 120 porcine mandibles were fractured at a defined location. After anatomic reduction, the fractures were fixed with a Delta plate, a TriLock Delta condyle trauma plate, or 2 4-hole miniplates (40 per group). Each group was subjected to linear loadings in 4 different directions with a universal mechanical testing machine (TIRA Test 2720). Yield load and yield displacement were measured for the 2 Delta plates and the 2 miniplates. Means were derived and compared for statistical significance using the Kruskal-Wallis test with a confidence level of 95% (P < .05).
  
  
  RESULTS
  None of the plates broke. In 4 cases using the double miniplate and in 2 cases using the Delta plate, osteosynthesis screw loosening was registered. In lateral-to-medial and anterior-to-posterior directions, the 2 miniplates tolerated the highest loads. From medial to lateral and from posterior to anterior, the TriLock Delta condyle trauma plate resisted the highest loads. However, there was a statistically significant difference among all osteosynthesis systems only for medial-to-lateral loads. Statistical analysis for displacement showed significant differences among all plates in the 4 directions.
  
  
  CONCLUSIONS
  This biomechanical study indicates that for rigid internal fixation of condylar fractures of the mandible, similar to 2 miniplates, the 2 Delta plates (Delta plate with gliding holes and TriLock Delta plate) fulfill the principles of a functional and stable osteosynthesis. Both are able to resist physiologic strains. The locking plate (TriLock Delta condyle trauma plate) has the advantages of greater primary stability and decreased likelihood of screw loosening.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University Hospital Carl Gustav Carus, Dresden Technical University, Dresden, Germany. dominik.haim@uniklinikum-dresden.de
authors.forename: Dominik
authors.initials: D
authors.lastname: Haim
authors.forename: Annett
authors.initials: A
authors.lastname: Müller
authors.forename: Henry
authors.initials: H
authors.lastname: Leonhardt
authors.forename: Alexander
authors.initials: A
authors.lastname: Nowak
authors.forename: Gerd
authors.initials: G
authors.lastname: Richter
authors.forename: Günter
authors.initials: G
authors.lastname: Lauer
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D001860:Bone Plates; D001863:Bone Screws; D002102:Cadaver; D005593:Fracture Fixation, Internal / Q000295:instrumentation*; D008335:Mandibular Condyle / Q000293:injuries* / Q000601:surgery; D008337:Mandibular Fractures / Q000601:surgery*; D011474:Prosthesis Design; D013314:Stress, Mechanical; D034421:Sus scrofa