title: Dose optimization by altering the operating potential and tube current exposure time product in dental cone beam CT: a systematic review.
abstract: OBJECTIVE
  Current guidelines highlight the need to optimize exposure parameters on CBCT equipment to levels that are as low as diagnostically acceptable. This systematic review aimed to answer the question "Can altering operating potential (kV) and tube current exposure time product (mAs) on CBCT machines reduce radiation dose to patients undergoing dental and/or maxillofacial scans without a detrimental impact on image quality/diagnostic accuracy?"
  
  
  METHODS
  Studies were selected and results reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. For each individual study, two authors (RG and JD or KH) independently extracted data using a specifically designed collection form, and an overall quality value was assigned using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Any disagreements in the overall quality value of a study were resolved by discussion between the current authors.
  
  
  RESULTS
  Nearly 75% of studies were considered to be of low or very low methodological quality using the GRADE system, and more studies stated that their results applied only in the specific situations they had investigated. However, most studies demonstrated that patient dose reduction is possible without a clinically relevant reduction in image quality.
  
  
  CONCLUSIONS
  For many CBCT machines, it should be possible to optimize one, or more, of the investigated exposure parameters and therefore reduce patient radiation dose, while maintaining diagnostic image quality for some diagnostic tasks. However, more rigorous research is still required.
authors.affiliation: 1 Dental Radiology Department, University Dental Hospital of Manchester, Manchester, UK.
authors.forename: Rebekah
authors.initials: R
authors.lastname: Goulston
authors.affiliation: 2 University of Manchester, School of Dentistry, Manchester, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Davies
authors.affiliation: 2 University of Manchester, School of Dentistry, Manchester, UK.
authors.forename: Keith
authors.initials: K
authors.lastname: Horner
authors.affiliation: 3 School of Health Sciences, University of Salford, Salford, UK.
authors.forename: Frederick
authors.initials: F
authors.lastname: Murphy
mesh_terms: D054893:Cone-Beam Computed Tomography / Q000379:methods*; D006801:Humans; D011829:Radiation Dosage; D000069079:Radiation Exposure; D011856:Radiographic Image Enhancement / Q000379:methods; D011861:Radiography, Dental / Q000379:methods*; D013997:Time Factors
keywords: cone-beam computed tomography; exposure parameters; image quality; radiation protection; review, systematic