title: B-mode versus A-mode ultrasonographic measurements of mucosal thickness in vivo.
abstract: OBJECTIVE
  The objective of this study was to compare the measurement accuracy of A-mode and B-mode ultrasonographic assessments of palatal masticatory mucosal thickness in vivo.
  
  
  METHODS
  Thickness of palatal masticatory mucosa in the molar region of 50 volunteers was measured once with a B-mode ultrasound device (10 MHz) combined with a standoff for intraoral applications. At identical reading points thickness was also assessed with an A-mode device (5 replicates) and by needle probing for determination of true thickness.
  
  
  RESULTS
  On average true thickness ranged between 2.9 and 3.3 mm (95% confidence intervals; median, 3.1 mm). B-mode ultrasonography overestimated truth by 0.19 mm (median) and differed significantly from truth (P =.008), whereas A-mode ultrasonography slightly underestimated true thickness by -0.05 mm (median). Limits of agreement were wider for A-mode ultrasonography (2.00 mm) than for B-mode ultrasonography (0.88 mm).
  
  
  CONCLUSIONS
  Because accuracy of 0.2 mm is acceptable for many clinical indications, B-mode and A-mode yield sufficient accuracy for measurements of mucosal thickness.
authors.affiliation: Department of Oral Surgery, Dental School, Johannes Gutenberg-University, Mainz, Germany. rschulze@mail.uni-mainz.de
authors.forename: Ralf K W
authors.initials: RK
authors.lastname: Schulze
authors.forename: Dejan
authors.initials: D
authors.lastname: Curić
authors.forename: Bernd
authors.initials: B
authors.lastname: d'Hoedt
mesh_terms: D006801:Humans; D009061:Mouth Mucosa / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D021362:Palate, Hard; D012016:Reference Values; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D014463:Ultrasonography / Q000295:instrumentation*