title: Quantification of incisal tooth wear in upper anterior teeth: conventional vs new method using toolmakers microscope and a three-dimensional measuring technique.
abstract: OBJECTIVE
  This study aimed to quantify tooth wear in upper anterior teeth using a new CAD-CAM Laser scanning machine, tool maker microscope and conventional tooth wear index.
  
  
  METHODS
  Fifty participants (25 males and 25 females, mean age = 25 ± 4 years) were assessed for incisal tooth wear of upper anterior teeth using Smith and Knight clinical tooth wear index (TWI) on two occasions, the study baseline and 1 year later. Stone dies for each tooth were prepared and scanned using the CAD-CAM Laser Cercon System. Scanned images were printed and examined under a toolmaker microscope to quantify tooth wear and then the dies were directly assessed under the microscope to measure tooth wear. The Wilcoxon Signed Ranks Test was used to analyze the data.
  
  
  RESULTS
  TWI scores for incisal edges were 0-3 and were similar at both occasions. Score 4 was not detected. Wear values measured by directly assessing the dies under the toolmaker microscope (range = 113 - 150 μm, mean = 130 ± 20 μm) were significantly more than those measured from Cercon Digital Machine images (range=52-80 μm, mean = 68 ± 23 μm) and both showed significant differences between the two occasions.
  
  
  CONCLUSIONS
  Wear progression in upper anterior teeth was effectively detected by directly measuring the dies or the images of dies under toolmaker microscope. Measuring the dies of worn dentition directly under tool maker microscope enabled detection of wear progression more accurately than measuring die images obtained with Cercon Digital Machine. Conventional method was the least sensitive for tooth wear quantification and was unable to identify wear progression in most cases.
authors.affiliation: Faculty of Dentistry, University of Jordan, Amman, Jordan; Faculty of Dentistry, AlJouf University, Sakaka, Saudi Arabia. Electronic address: alomirim@yahoo.co.uk.
authors.forename: Mahmoud K
authors.initials: MK
authors.lastname: Al-Omiri
authors.forename: Mohd G
authors.initials: MG
authors.lastname: Sghaireen
authors.forename: Bader K
authors.initials: BK
authors.lastname: Alzarea
authors.forename: Edward
authors.initials: E
authors.lastname: Lynch
mesh_terms: D000328:Adult; D017076:Computer-Aided Design / Q000295:instrumentation*; D003481:Cuspid / Q000473:pathology*; D003743:Dental Enamel / Q000473:pathology; D003789:Dental Pulp Exposure / Q000175:diagnosis; D003804:Dentin / Q000473:pathology; D003809:Dentin, Secondary / Q000473:pathology; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007180:Incisor / Q000473:pathology*; D007834:Lasers; D008297:Male; D008853:Microscopy / Q000295:instrumentation*; D003765:Models, Dental; D057085:Tooth Wear / Q000145:classification / Q000175:diagnosis*; D055815:Young Adult
keywords: 3D measuring; Cercon brain machine; Tool makers microscope; Tooth wear; Tooth wear index