title: A comparative study of three periapical radiographic techniques for endodontic working length estimation.
abstract: OBJECTIVE
  To compare the diagnostic quality of endodontic working length estimation films produced using film holders with those taken using the bisecting angle technique and to assess the level of acceptance of film holders by operator and patient.
  
  
  METHODS
  Five post-graduate and 20 final year undergraduate students attending a UK Dental School produced working length radiographs using either the paralleling or the bisecting angle technique. The paralleling group used one of two film holders, the Endoray II or the XCP Endodontic Instrument, on alternate patients. An assessment of the ease of use of the device and the patients' views on the comfort of the examination were recorded. Each radiograph was examined simultaneously by two assessors, scored for film faults and diagnostic acceptability. Statistical data was derived using the Mann-Whitney U test and Cohen's kappa.
  
  
  RESULTS
  The rates of unacceptable radiographs for the XCP Endodontic Instrument, Endoray II and the bisecting angle techniques were 12.2%, 21.4% and 48.6%, respectively. The combined percentage of unacceptable paralleling technique films (16.7%) was highly significantly different (P < 0.001) when compared with the bisecting angle technique (48.6%). The paralleling technique produced a significant reduction in incorrect vertical angulation (P < 0.001), cone cutting (P < 0.001) and incorrect film placement (P < 0.001). Film holders were rated either excellent or good in 90% of examinations by operators and 47.5% of patients reported no discomfort.
  
  
  CONCLUSIONS
  These results support the use of the film holders for endodontic working length estimation.
authors: The School of Dentistry, University of Manchester, Higher Cambridge Street, Manchester, UK.
authors: D
authors: D
authors: Kazzi
authors: K
authors: K
authors: Horner
authors: A C
authors: AC
authors: Qualtrough
authors: Y
authors: Y
authors: Martinez-Beneyto
authors: V E
authors: VE
authors: Rushton
mesh_terms: D001291:Attitude of Health Personnel; D015331:Cohort Studies; D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging*; D003815:Dentists; D006801:Humans; D017060:Patient Satisfaction; D010486:Periapical Tissue / Q000000981:diagnostic imaging*; D011856:Radiographic Image Enhancement / Q000295:instrumentation / Q000379:methods; D016300:Radiography, Bitewing / Q000295:instrumentation / Q000379:methods; D018915:Root Canal Preparation / Q000379:methods*; D013335:Students, Dental; D014962:X-Ray Film