title: Effects of near-infrared LED therapy on experimental tooth replantation in rats.
abstract: OBJECTIVE
  Dental avulsion damages periodontal tissues and may induce dentoalveolar ankylosis and root resorption after replantation. The aim of this work was to evaluate the effects of light-emitting diode (LED) therapy after tooth replantation.
  
  
  METHODS
  The upper right incisors of 36 male Wistar rats were extracted and replanted after 15 min. The control group (Co, n = 18) was submitted to replantation and the LED group (n = 18) was submitted to replantation and LED therapy (940 nm, 4 J cm-2) for three consecutive days (0, 24, and 48 h). Six animals from each group were euthanized at 7, 14, and 21 days for histological analysis. The upper left incisors were used as a negative control. Data were compared using the Fisher exact test, considering P < 0.05.
  
  
  RESULTS
  After 7 days, the Co (73.3%) and LED (72.2%) groups presented areas of periodontal ligament necrosis. However, periodontal ligament necrosis was more frequent in the LED group at 14 (70%, P < 0.05) and 21 days (43.2%, P < 0.05) in relation to the Co group (33 and 21.6%). Inflammatory cell infiltration was more frequent in the Co group at 7 days (100%) than the LED group (24.4%, P < 0.05), but increased in the LED group after 21 days (83.3%, P < 0.05). Bone necrosis was more frequent in the LED group after 14 (79%, P < 0.05) and 21 days (60%, P < 0.005) than in the Co group (45% and 20%). Bone repair was evident in the Co group at 14 days. All of the replanted teeth had pulp necrosis.
  
  
  CONCLUSIONS
  The results suggest that the application of LED therapy up to 48 h after tooth replantation may delay periodontal ligament repair.
authors.affiliation: Department of Oral Medicine e Pediatric Dentistry, State University of Londrina, Londrina, Brasil.
authors.forename: Débora
authors.initials: D
authors.lastname: Pigatto Mitihiro
authors.affiliation: Department of Histology, State University of Londrina, Londrina, Brasil.
authors.forename: Solange
authors.initials: S
authors.lastname: de Paula Ramos
authors.affiliation: Department of Oral Medicine e Pediatric Dentistry, State University of Londrina, Londrina, Brasil.
authors.forename: Janaína
authors.initials: J
authors.lastname: Corazza Montero
authors.affiliation: Department of Histology, State University of Londrina, Londrina, Brasil.
authors.forename: Aline
authors.initials: A
authors.lastname: Alves Campos
authors.affiliation: Department of Physics, State University of Londrina, Londrina, Brasil.
authors.forename: Dari
authors.initials: D
authors.lastname: de Oliveira Toginho Filho
authors.affiliation: Department of Oral Medicine e Pediatric Dentistry, State University of Londrina, Londrina, Brasil.
authors.forename: Cassia Cilene
authors.initials: CC
authors.lastname: Dezan Garbelini
mesh_terms: D000818:Animals; D007180:Incisor / Q000528:radiation effects* / Q000601:surgery*; D008297:Male; D010789:Phototherapy / Q000379:methods*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D014090:Tooth Replantation
keywords: inflammation; periodontium; phototherapy; tooth avulsion