Danilo-Louzada de Oliveira1, Victor-Eduardo de Souza-Batista2, Letícia Holobenko3, Joel-Ferreira Santiago-Junior3, Eduardo-Piza Pellizzer4, Paulo-Domingos Ribeiro-Junior5. 1. Department of Oral and Maxillofacial Surgery, Universidade do Oeste Paulista (UNOESTE), R. José Bongiovani, 700, 19050-920, Presidente Prudente, SP, Brazil. 2. Department of Prosthodontics, UNOESTE, R. José Bongiovani, 700, 19050-920, Presidente Prudente, SP, Brazil. 3. Department of Health Sciences, Universidade do Sagrado Coração, R. Irmã Arminda, 10-50, 17011-160, Bauru, SP, Brazil. 4. Department of Dental Materials and Prosthodontics, School of Dentistry, Universidade Estadual Paulista (UNESP), Araçatuba, SP, Brazil. R. José Bonifacio, 793, 10-50, 16015-050, Araçatuba, SP, Brazil. 5. Department of Oral and Maxillofacial Surgery, Universidade do Sagrado Coração, R. Irmã Arminda, 10-50, 17011-160, Bauru, SP, Brazil.
Abstract
BACKGROUND: This photoelastic analysis evaluated stress distribution in different osteosynthesis systems, conventional and locking, used for treatment of mandibular angle fractures with a single plate. MATERIAL AND METHODS: Angle fractures were simulated in mandibles made of photoelastic resin. Following Champy's method, plate osteosynthesis was performed. The samples were divided into five groups: Group 1, non-fractured mandible; Group 2, two screws were installed in each segment using a conventional system; Group 3, two screws were installed in each segment using a locking system; Group 4, three screws were installed in the proximal segment and four screws in the distal segment using a conventional plate; Group 5, three screws were installed in the proximal segment and four screws in the distal segment using a locking plate. In an universal testing machine coupled to a polariscope, a load was applied to the first molar 10 times. The 50 images were randomly numbered and analyzed qualitatively and quantitatively by two raters. RESULTS: The locking system promoted better stress distribution along the osteosynthesis. The locking system reduced stress magnitude in the distal segment, with a significant between-group difference (P≤ 0.001). CONCLUSIONS: The locking plate/screw system can distribute stress more evenly throughout the osteosynthesis, especially when long seven-hole plates are used. Key words:Internal fracture fixation, osteosynthesis, mandibular fracture, bone plates. Copyright:
BACKGROUND: This photoelastic analysis evaluated stress distribution in different osteosynthesis systems, conventional and locking, used for treatment of mandibular angle fractures with a single plate. MATERIAL AND METHODS: Angle fractures were simulated in mandibles made of photoelastic resin. Following Champy's method, plate osteosynthesis was performed. The samples were divided into five groups: Group 1, non-fractured mandible; Group 2, two screws were installed in each segment using a conventional system; Group 3, two screws were installed in each segment using a locking system; Group 4, three screws were installed in the proximal segment and four screws in the distal segment using a conventional plate; Group 5, three screws were installed in the proximal segment and four screws in the distal segment using a locking plate. In an universal testing machine coupled to a polariscope, a load was applied to the first molar 10 times. The 50 images were randomly numbered and analyzed qualitatively and quantitatively by two raters. RESULTS: The locking system promoted better stress distribution along the osteosynthesis. The locking system reduced stress magnitude in the distal segment, with a significant between-group difference (P≤ 0.001). CONCLUSIONS: The locking plate/screw system can distribute stress more evenly throughout the osteosynthesis, especially when long seven-hole plates are used. Key words:Internal fracture fixation, osteosynthesis, mandibular fracture, bone plates. Copyright:
Authors: R Gutwald; R Schön; M Metzger; K Kreutzer; B Rahn; R Schmelzeisen; S Sauerbier Journal: Int J Oral Maxillofac Surg Date: 2010-11-16 Impact factor: 2.789
Authors: Rudolf Seemann; Kurt Schicho; Arno Wutzl; Gregor Koinig; Wolfgang P Poeschl; Gerald Krennmair; Rolf Ewers; Clemens Klug Journal: J Oral Maxillofac Surg Date: 2010-03 Impact factor: 1.895