title: In vivo temperature rise in anesthetized human pulp during exposure to a polywave LED light curing unit.
abstract: OBJECTIVE
  This in vivo study evaluated pulp temperature (PT) rise in human premolars during exposure to a light curing unit (LCU) using selected exposure modes (EMs).
  
  
  METHODS
  After local Ethics Committee approval, intact first upper premolars, requiring extraction for orthodontic reasons, from 8 volunteers, received infiltrative and intraligamental anesthesia. The teeth (n=15) were isolated using rubber dam and a minute pulp exposure was attained. A sterile probe from a wireless, NIST-traceable, temperature acquisition system was inserted directly into the coronal pulp chamber, and real time PT (°C) was continuously monitored while the buccal surface was exposed to polywave light from a LED LCU (Bluephase 20i, Ivoclar Vivadent) using selected EMs allowing a 7-min span between each exposure: 10-s either in low (10-s/L) or high (10-s/H); 5-s-turbo (5-s/T); and 60-s-high (60-s/H) intensities. Peak PT values and PT increases from baseline (ΔT) after exposure were subjected to one-way, repeated measures ANOVAs, and Bonferroni's post hoc tests (α=0.05). Linear regression analysis was performed to establish the relationship between applied radiant exposure and ΔT.
  
  
  RESULTS
  All EMs produced higher peak PT than the baseline temperature (p<0.001). The 60-s/H mode generated the highest peak PT and ΔT (p<0.001), with some teeth exhibiting ΔT higher than 5.5°C. A significant, positive relationship between applied radiant exposure and ΔT (r(2)=0.916; p<0.001) was noted.
  
  
  CONCLUSIONS
  Exposing intact, in vivo anesthetized human upper premolars to a polywave LED LCU increases PT, and depending on EM and the tooth, PT increase can be higher than the critical ΔT, thought to be associated with pulpal necrosis.
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Rua General Carlos Cavalcanti, 4748, Uvaranas, Ponta Grossa, PR 84030-900, Brazil.
authors.forename: Patrício
authors.initials: P
authors.lastname: Runnacles
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Rua General Carlos Cavalcanti, 4748, Uvaranas, Ponta Grossa, PR 84030-900, Brazil. Electronic address: cesararrais@yahoo.com.br.
authors.forename: Cesar Augusto Galvão
authors.initials: CA
authors.lastname: Arrais
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Rua General Carlos Cavalcanti, 4748, Uvaranas, Ponta Grossa, PR 84030-900, Brazil.
authors.forename: Marcia Thais
authors.initials: MT
authors.lastname: Pochapski
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Rua General Carlos Cavalcanti, 4748, Uvaranas, Ponta Grossa, PR 84030-900, Brazil.
authors.forename: Fábio André
authors.initials: FA
authors.lastname: Dos Santos
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Rua General Carlos Cavalcanti, 4748, Uvaranas, Ponta Grossa, PR 84030-900, Brazil.
authors.forename: Ulisses
authors.initials: U
authors.lastname: Coelho
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Rua General Carlos Cavalcanti, 4748, Uvaranas, Ponta Grossa, PR 84030-900, Brazil.
authors.forename: João Carlos
authors.initials: JC
authors.lastname: Gomes
authors.affiliation: Department of Dental Materials, Piracicaba Dental School, Av. Limeira, 901, Piracicaba, SP 13414-903, Brazil.
authors.forename: Mário Fernando
authors.initials: MF
authors.lastname: De Goes
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Rua General Carlos Cavalcanti, 4748, Uvaranas, Ponta Grossa, PR 84030-900, Brazil.
authors.forename: Osnara Maria Mongruel
authors.initials: OM
authors.lastname: Gomes
authors.affiliation: Dental Materials Section, Department of Oral Rehabilitation, Georgia Regents University, College of Dental Medicine, Room GC 4344, Georgia Regents University, 1120 15th Street, Augusta, GA 30912, USA.
authors.forename: Frederick Allen
authors.initials: FA
authors.lastname: Rueggeberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000766:Anesthesia, Dental; D001641:Bicuspid; D001831:Body Temperature / Q000502:physiology*; D002648:Child; D055117:Curing Lights, Dental; D003782:Dental Pulp / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male
keywords: Body temperature changes; Body temperature/radiation effects; Dental pulp cavity; Dental pulp/radiation effects; Humans; Light-curing of dental resins