title: Effective dose equivalent and effective dose: comparison for common projections in oral and maxillofacial radiology.
abstract: OBJECTIVE
  Effective dose equivalents (H(E)) and effective doses (E) for radiographic projections common in dentistry, calculated from the same organ dose distributions, are presented to determine whether the 2 quantities can be directly compared.
  
  
  METHODS
  Doses to all organs and tissues in the head, neck, trunk, and proximal extremities were determined for each projection (intraoral full-mouth radiographic survey, panoramic, cephalometric, temporomandibular tomograms, and submentovertex view) by computer simulation with Monte Carlo methods. H(E) and E were calculated from these complete distributions and by methods prescribed by the International Commission on Radiological Protection (ICRP).
  
  
  RESULTS
  H(E) and E computed from complete dose distributions were found comparable within a few percentage points. However, those computed by strict application of ICRP methods were not.
  
  
  CONCLUSIONS
  For radiographic projections with highly localized dose distributions, such as those common in dentistry, direct comparison of H(E) and E may not be meaningful, unless both computation algorithms are known.
authors.affiliation: Vanderbilt University Medical Center, Department of Radiology and Radiological Sciences, Nashville, TN, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Gibbs
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D006801:Humans; D009010:Monte Carlo Method; D009928:Organ Specificity; D011829:Radiation Dosage; D011861:Radiography, Dental / Q000706:statistics & numerical data*; D011874:Radiometry / Q000706:statistics & numerical data*; D012015:Reference Standards; D013269:Stochastic Processes