title: Effects of low-power red laser on dentine-pulp interface after cavity preparation. An ultrastructural study.
abstract: OBJECTIVE
  Studies on the influence of low-power red laser on the repair of dental structures are very scarce. This study investigated the effects of the laser therapy on the ultrastructure of the dentine-pulp interface after conservative class I cavity preparation.
  
  
  METHODS
  Two female volunteers with 8 premolars indicated for extraction for orthodontic reasons were recruited. Class I cavities were prepared and the teeth were randomly divided into two groups. The first group received treatment with a GaA1As laser, lambda=660nm, power of 30mW and energy dose of 2J/cm(2), directly and perpendicularly into the cavity in a single visit. After the irradiation, the cavities were filled with composite resin. The second group received the same treatment, except by the laser therapy.
  
  
  RESULTS
  Twenty-eight days post-preparation, the teeth were extracted and processed for transmission electron microscopy analysis. Two sound teeth, without cavity preparation, were also studied. The irradiated group presented odontoblast process in higher contact with the extracellular matrix and the collagen fibrils appeared more aggregated and organised than those of control group. These results were also observed in the healthy teeth.
  
  
  CONCLUSIONS
  These findings suggest that laser irradiation accelerates the recovery of the dental structures involved in the cavity preparation at the predentine region.
authors.affiliation: Professional Master Lasers in Dentistry, IPEN-CNEN/SP, São Paulo, Brazil.
authors.forename: Bruno Miranda
authors.initials: BM
authors.lastname: Godoy
authors.forename: Victor Elias
authors.initials: VE
authors.lastname: Arana-Chavez
authors.forename: Silvia Cristina
authors.initials: SC
authors.lastname: Núñez
authors.forename: Martha Simões
authors.initials: MS
authors.lastname: Ribeiro
mesh_terms: D000328:Adult; D003094:Collagen / Q000528:radiation effects / Q000648:ultrastructure; D003188:Composite Resins; D003737:Dental Cavity Preparation / Q000145:classification; D003782:Dental Pulp / Q000528:radiation effects* / Q000648:ultrastructure; D003793:Dental Restoration, Permanent; D003804:Dentin / Q000528:radiation effects* / Q000648:ultrastructure; D005109:Extracellular Matrix / Q000528:radiation effects / Q000648:ultrastructure; D005260:Female; D006801:Humans; D054023:Lasers, Semiconductor / Q000627:therapeutic use*; D028022:Low-Level Light Therapy; D046529:Microscopy, Electron, Transmission; D009804:Odontoblasts / Q000528:radiation effects / Q000648:ultrastructure; D011829:Radiation Dosage
chemical_list: D003188:Composite Resins; D003094:Collagen