Objectives. The purpose of this study was to measure the development of contraction stress of three composite resin restorative materials during photo-polymerization: a micro-hybrid composite (Filtek Z250,3M ESPE, St. Paul, MN, USA); a nano-filled composite (Filtek Supreme, 3M ESPE, St. Paul, MN, USA); and a low-shrinkage composite (AElite LS, Bisco Inc., Schaumburg, IL, USA). Methods. Curing shrinkage stress was measured using a stress-analyzer. Composites were polymerized with a halogen-curing unit (VIP, Bisco Inc., Schaumburg, IL, USA) for 40 s. The contraction force (N) generated during polymerization was continuously recorded for 150 s after photo-initiation. Contraction stress (MPa) was calculated at 20, 40, 60 and 150 s. Data were statistically analyzed. Results. The low-shrinkage composite Elite LS exhibited the lowest stress values compared to other materials (p < 0.05). Statistical analysis did not show significant differences between Filtek Z250 and Filtek Supreme. Significance. The low-shrinkage composite showed lower contraction stress than micro-hybrid and nano-filled composite. Ideally, non-shrinking resins would represent the ultimate solution to overcome polymerization contraction and stress-related problems. (C) 2007 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
Assessment of polymerization contraction stress of three composite resins / Cadenaro M; Biasotto M; Scuor N; Breschi L; Davidson CL; Di Lenarda R. - In: DENTAL MATERIALS. - ISSN 0109-5641. - STAMPA. - 24:5(2008), pp. 681-685. [10.1016/j.dental.2007.06.031]
Assessment of polymerization contraction stress of three composite resins
BRESCHI, LORENZO;
2008
Abstract
Objectives. The purpose of this study was to measure the development of contraction stress of three composite resin restorative materials during photo-polymerization: a micro-hybrid composite (Filtek Z250,3M ESPE, St. Paul, MN, USA); a nano-filled composite (Filtek Supreme, 3M ESPE, St. Paul, MN, USA); and a low-shrinkage composite (AElite LS, Bisco Inc., Schaumburg, IL, USA). Methods. Curing shrinkage stress was measured using a stress-analyzer. Composites were polymerized with a halogen-curing unit (VIP, Bisco Inc., Schaumburg, IL, USA) for 40 s. The contraction force (N) generated during polymerization was continuously recorded for 150 s after photo-initiation. Contraction stress (MPa) was calculated at 20, 40, 60 and 150 s. Data were statistically analyzed. Results. The low-shrinkage composite Elite LS exhibited the lowest stress values compared to other materials (p < 0.05). Statistical analysis did not show significant differences between Filtek Z250 and Filtek Supreme. Significance. The low-shrinkage composite showed lower contraction stress than micro-hybrid and nano-filled composite. Ideally, non-shrinking resins would represent the ultimate solution to overcome polymerization contraction and stress-related problems. (C) 2007 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
