title: In vitro study investigating the mass of tooth structure removed following endodontic and restorative procedures.
abstract: BACKGROUND
  There is limited scientific evidence which quantifies the amount of tissue removed during endodontic and restorative procedures.
  
  
  OBJECTIVE
  The purpose of this study was to measure and compare the mass of tissue structure removed from incisor and canine teeth following successive preparations.
  
  
  METHODS
  Twenty-two intact, disease- and restoration-free teeth (n=11/group) were collected from consenting patients undergoing dental extractions at Eastman Dental Hospital. The teeth were stored in 4% formaldehyde saline and successively prepared for an access opening (AC), endodontic instrumentation (EI), porcelain laminate veneer (PC), metal-ceramic (MC) crown, and post-and-core (PC) preparations. The baseline mass for each tooth was measured and recorded, in grams, at baseline and after each preparation, on a digital analytical balance. A standard protocol was applied to ensure accurate mass measurements. Repeated measures analysis of variance (ANOVA) was used to make comparisons between the incisor and canine groups (alpha =.05) for actual mass of tooth in milligrams, percentage of tooth mass remaining compared to baseline, and percentage decrease in mass compared to the preceding procedure.
  
  
  RESULTS
  The estimated marginal percentage mass lost was significantly greater (P<.001) in the incisor group compared to the canine group, as an overall trend, with the incisors losing proportionally more mass for each procedure (P<.001).
  
  
  CONCLUSIONS
  Mean percentage of removed tooth tissue increased successively from EI, AC, PC, and PV preparation, with greatest change from the previous procedure occurring for MC crown preparation.
authors.affiliation: Restorative Dentistry, Eastman Dental Hospital and UCL Eastman Dental Institute, London, UK. selahussain@hotmail.com
authors.forename: Sela K F
authors.initials: SK
authors.lastname: Hussain
authors.forename: Ailbhe
authors.initials: A
authors.lastname: McDonald
authors.forename: David R
authors.initials: DR
authors.lastname: Moles
mesh_terms: D000704:Analysis of Variance; D003442:Crowns; D003481:Cuspid / Q000473:pathology*; D003801:Dental Veneers; D006801:Humans; D007180:Incisor / Q000473:pathology*; D009929:Organ Size; D011176:Post and Core Technique; D018915:Root Canal Preparation / Q000295:instrumentation; D019231:Tooth Preparation, Prosthodontic