200 Are Dentists Adequately Curing Resin Composite Restorations?

Friday, September 6, 2013: 8 a.m. - 10:30 a.m.
Location: Auditorium
Presentation Type: Oral Session
A. SANTINI1, S. TURNER1, and C. FELIX2, 1University of Edinburgh, Edinburgh, Scotland, 2BlueLight analytics inc, Halifax, NS, Canada
Objective: More dentists are supplying, and more patients are requesting, resin based composites (RBCs). Longevity of RBCs versus amalgam restorations is often questioned. A principal factor in adequately curing RBCs is operator efficiency and knowledge of light curing units (LCU). A recent study indicated dentists were not well versed in this knowledge. The current study was undertaken to ascertain whether the current level of knowledge enables adequate energy levels to be delivered to RBCs.

Method: Data were collected in the UK (Scotland, England, N. Ireland) using MARC® Patient Simulator (MARC® PS, BlueLight™, Halifax, Canada). The dentist or nurse was asked to use their LCU to cure each of two simulated restorations, one anterior, one posterior, as they would under normal clinical conditions using an RBC shade A3 or equivalent. A variety of protective eye wear was supplied and the operator could chose the one normally used. The following data were collected: type of LCU; total curing time (time x no. cycles); maximum irradiance; energy delivered in 420-540nm (blue light); energy delivered in 380-420nm (violet light); time taken to achieve the minimum energy requirement of 16J/cm2.

Result: 213 dentists and nurses took part, using 23 different makes of LCU. Ratio of LED/QTH 70/30; 78% delivered adequate energy (16 J/cm2 according to EU) in the time they cured to anterior teeth and 22% to posterior teeth; < 5% increased time or cycles when curing posterior v anterior teeth; only two LEDs delivered more than 2.00 J/cm2in violet range;  > 60% operators chose not to use protective eyewear.

Conclusion: The results suggest that dentists and dental nurses are not fully aware of the fact that their LCUs and practice protocols are not delivering adequate energy when curing their patient’s restorations. Under-curing of restorations is known to lead to premature failure and replacement.

Keywords: Curing lights, Delivery systems and Dental materials
Presenting author's disclosure statement: ** MISSING DISCLOSURE **