title: Evaluation of cyclic and linear mechanical resistance of prebent and manually-bent plates used for maxillary advancement in orthognathic surgery.
abstract: The aim of the present study was to compare prebent and manually-bent plates used in maxillary advancement. The prebent plates were fixed in polyurethane blocks for the linear test and aluminium blocks for the cyclic test, and the manually-bent plates were fixed in polyurethane and aluminium blocks. The linear load tests were done using an Instron®4411 mechanical testing machine and the cyclic test with an Instron®E3000 testing machine. The linear mechanical test showed that there was no significant difference between the plates. In the cyclic test the prebent plates reached the limit of 500000 cycles without fracturing whereas the manually-bent plate group fractured before reaching the limit of cycles (p=0.008). The decision to use prebent or manually-bent plates during operations should be influenced by the production of the bends and their consequent brittleness.
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Dentistry of Piracicaba, State University of Campinas (UNICAMP), Piracicaba, SP, Brazil. Electronic address: andrezzalauria@gmail.com.
authors.forename: Andrezza
authors.initials: A
authors.lastname: Lauria
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Dentistry of Piracicaba, State University of Campinas (UNICAMP), Piracicaba, SP, Brazil.
authors.forename: Raquel Correia
authors.initials: RC
authors.lastname: de Medeiros
authors.affiliation: Department of Oral and Maxillofacial Surgery, Brazilian Red Cross Hospital, São Paulo, SP, Brazil.
authors.forename: Danillo Costa
authors.initials: DC
authors.lastname: Rodrigues
authors.affiliation: Department of Oral and Maxillofacial Surgery, Brazilian Red Cross Hospital, São Paulo, SP, Brazil.
authors.forename: Fábio Ricardo Loureiro
authors.initials: FR
authors.lastname: Sato
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Dentistry of Piracicaba, State University of Campinas (UNICAMP), Piracicaba, SP, Brazil; Department of Oral and Maxillofacial Surgery, Brazilian Red Cross Hospital, São Paulo, SP, Brazil.
authors.forename: Roger William Fernandes
authors.initials: RW
authors.lastname: Moreira
mesh_terms: D001696:Biomechanical Phenomena; D001860:Bone Plates; D006801:Humans; D008437:Maxilla; D056948:Orthognathic Surgical Procedures; D013314:Stress, Mechanical
keywords: Bone plates; Fatigue; Maxillary osteotomy; Mechanical stress