title: The effect of interincisal opening, cavity location and operator experience on the energy delivered by a light-curing unit to a simulated dental restoration.
abstract: BACKGROUND
  Curing of resin-based composites depends on the delivery of adequate total energy, which may be operator dependent. Aim To determine the effect of interincisal opening, cavity location and operator experience on the total energy delivered to simulated cavity preparation sites.
  
  
  METHODS
  Three cohorts were included: junior dental nurses, senior dental nurses and qualified dentists (N=5, each cohort). Each operator (participant) followed the same procedure and light-cured two simulated restorations in a MARC patient simulator using a Demi light-curing unit for 20 seconds in each of the following situations: left upper second molar (UL7), interincisal opening at both 25 mm and 45 mm; upper central incisor (UR1), interincisal opening at 45mm. The light energy delivered by each operator in each situation was recorded. Five readings for each operator were taken at each interincisal distance. Statistical comparisons of delivered energy (J/cm2) between interincisal openings, location and groups in the total energy delivered were performed using the Kruskal-Wallis nonparametric test: alpha = 0.05.
  
  
  RESULTS
  Less total energy was delivered to the posterior cavity at 25mm (12.0 +/- 5.3 J/cm2) than at 45mm (16.9 +/- 5.6 J/cm2) by all operators (P < 0.05). At 45 mm, less total energy was delivered to the posterior cavity compared to the anterior cavity (25.1 +/- 7.4 J/cm2; P < 0.05). There was no statistically significant difference between junior nurses and qualified dentists (P > 0.05) but there was a significant difference in the total energy delivered between senior nurses (20.1 +/- 7.8 J/cm2) and junior nurses (17.5 +/- 7.6 J/cm2) and between senior nurses and qualified dentists (16.6 +/- 8.7 J/cm2) (P < 0.05).
  
  
  CONCLUSIONS
  Interincisal mouth opening, location of the cavity and operator experience affected the total energy delivered to cavities in a simulated clinical environment.
authors.forename: Nor Asilah
authors.initials: NA
authors.lastname: Harun
authors.forename: Ario
authors.initials: A
authors.lastname: Santini
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Roebuck
mesh_terms: D002983:Clinical Competence; D015331:Cohort Studies; D003188:Composite Resins / Q000528:radiation effects*; D055117:Curing Lights, Dental; D003727:Dental Auxiliaries; D003737:Dental Cavity Preparation / Q000145:classification*; D003764:Dental Materials / Q000528:radiation effects*; D003793:Dental Restoration, Permanent / Q000295:instrumentation*; D003815:Dentists; D006801:Humans; D007180:Incisor / Q000033:anatomy & histology; D055115:Light-Curing of Dental Adhesives / Q000295:instrumentation / Q000379:methods; D008348:Manikins; D008963:Molar / Q000033:anatomy & histology; D009055:Mouth / Q000033:anatomy & histology*; D011829:Radiation Dosage; D013057:Spectrum Analysis / Q000295:instrumentation
chemical_list: D003188:Composite Resins; D003764:Dental Materials