title: Effects on Bone Tissue After Osteotomy with Different High-Energy Lasers: An Ex Vivo Study.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the application of Er:YAG and Er,Cr:YSGG lasers during osteotomy in bovine bone blocks.
  
  
  BACKGROUND
  Er:YAG/Er,Cr:YSGG lasers for osteotomy procedures have been used to induce tissue ablation without thermal damage. However, even these lasers can induce thermal damages, which can cause a delay on the bone healing.
  
  
  METHODS
  Sixty standardized bovine bone mandible samples were divided into three groups with 20 samples each: Group 1, Bur; Group 2, Er:YAG laser; and Group 3, Er,Cr:YSGG laser. Two irradiations/cuts were made in each sample. The first was performed until the sample was completely separated into two fragments, and the time required for this procedure was recorded in seconds. The second irradiation/cut was made the same way as the first one; however, it was made partially, without separating the sample into two fragments, but rather making sulci ∼1.5-2 mm deep. Ten samples in each group were used to evaluate the surface morphology of the osteotomy by scanning electron microscopy (SEM), while the other 10 samples were submitted to descriptive histological analysis.
  
  
  RESULTS
  The bur was the instrument that performed the osteotomy in the shortest amount of time (p < 0.05). All the instruments caused thermal damage; however, the Er,Cr:YSGG laser was the only type that induced carbonization.
  
  
  CONCLUSIONS
  The Er:YAG laser induced the lowest degree of thermal damage in bone tissue after osteotomy; however, a shorter clinical time was required to perform the osteotomy in the bur group.
authors.affiliation: University Estadual Paulista UNESP, Araraquara School of Dentistry , Araraquara, SP, Brazil .
authors.forename: Guilherme José Pimentel Lopes
authors.initials: GJ
authors.lastname: de Oliveira
authors.affiliation: University Estadual Paulista UNESP, Araraquara School of Dentistry , Araraquara, SP, Brazil .
authors.forename: Conrado Nogueira Campelo
authors.initials: CN
authors.lastname: Rodrigues
authors.affiliation: University Estadual Paulista UNESP, Araraquara School of Dentistry , Araraquara, SP, Brazil .
authors.forename: Lívia Rodrigues
authors.initials: LR
authors.lastname: Perussi
authors.affiliation: University Estadual Paulista UNESP, Araraquara School of Dentistry , Araraquara, SP, Brazil .
authors.forename: Alessandra Nara
authors.initials: AN
authors.lastname: de Souza Rastelli
authors.affiliation: University Estadual Paulista UNESP, Araraquara School of Dentistry , Araraquara, SP, Brazil .
authors.forename: Rosemary Adriana Chiérici
authors.initials: RA
authors.lastname: Marcantonio
authors.affiliation: University Estadual Paulista UNESP, Araraquara School of Dentistry , Araraquara, SP, Brazil .
authors.forename: Fábio Luiz Camargo Villela
authors.initials: FL
authors.lastname: Berbert
mesh_terms: D000818:Animals; D002417:Cattle; D006358:Hot Temperature; D066298:In Vitro Techniques; D053844:Lasers, Solid-State; D008334:Mandible / Q000601:surgery / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D010027:Osteotomy / Q000295:instrumentation*; D013499:Surface Properties