title: Assessment of pulpal vitality using laser speckle imaging.
abstract: OBJECTIVE
  The pulpal chamber of each tooth contains the vasculature necessary to maintain a viable tooth. A critical need exists to develop an objective, repeatable method to assess pulpal viability. We hypothesized that the existence of blood perfusion within the pulp can be determined with analysis of laser speckle imaging (LSI) patterns generated by transillumination of the tooth.
  
  
  METHODS
  We used nine extracted human cuspids and incisors. A Tygon tube was inserted into a channel created within each tooth and Intralipid pumped through the tube in a controlled manner with a syringe infusion pump. We evaluated the feasibility of LSI for flow assessment using both transillumination and epiillumination imaging configurations. With the transillumination geometry, we also assessed the effect of the angle of incidence of the probe laser light on the speckle flow index (SFI) values extracted from the collected speckle images.
  
  
  RESULTS
  Transillumination LSI, and not epiillumination LSI, enables differentiation between the absence and presence of perfusion in an in vitro tooth model. SFI values are insensitive to the relative angle of incidence of the laser light, over a wide range of angles.
  
  
  CONCLUSIONS
  Our preliminary in vitro data suggest that transillumination LSI is a promising method to identify the presence of blood flow in the pulpal chamber. Future in vivo evaluation is warranted.
authors.affiliation: Department of Surgery, Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612, USA.
authors.forename: Charles
authors.initials: C
authors.lastname: Stoianovici
authors.forename: Petra
authors.initials: P
authors.lastname: Wilder-Smith
authors.forename: Bernard
authors.initials: B
authors.lastname: Choi
mesh_terms: D003782:Dental Pulp / Q000098:blood supply*; D003813:Dentistry / Q000379:methods; D006801:Humans; D007834:Lasers