STATEMENT OF PROBLEM: Severe thermal stresses caused by food-induced temperature changes may result in dowel-and-core failure. PURPOSE: This study investigated the influence of thermal stresses on various combinations of dowel-and-core materials of a restored endodontically treated incisor. MATERIAL AND METHODS: A 2-dimensional finite element model was constructed in a labiolingual cross-sectional view of a maxillary central incisor, a dowel, a core, and the supporting tissues to investigate thermal stress distribution. Four combinations of dowel-and-core materials were used: (1) gold/gold, (2) stainless steel/resin composite, (3) stainless steel/amalgam, and (4) carbon fiber-reinforced composite/resin composite. For thermal analysis, a cold irritant (0 degrees C) was applied on the outer surface of a metal-ceramic crown for 7 seconds. RESULTS: The metal dowel and core generated lower thermal stresses in the restorations and dentin than the nonmetallic dowel and cores. CONCLUSION: Stress level is closely related to the degree of thermal gradient. The nonmetallic dowel and cores generated greater thermal stresses than metal dowel and cores.
STATEMENT OF PROBLEM: Severe thermal stresses caused by food-induced temperature changes may result in dowel-and-core failure. PURPOSE: This study investigated the influence of thermal stresses on various combinations of dowel-and-core materials of a restored endodontically treated incisor. MATERIAL AND METHODS: A 2-dimensional finite element model was constructed in a labiolingual cross-sectional view of a maxillary central incisor, a dowel, a core, and the supporting tissues to investigate thermal stress distribution. Four combinations of dowel-and-core materials were used: (1) gold/gold, (2) stainless steel/resin composite, (3) stainless steel/amalgam, and (4) carbon fiber-reinforced composite/resin composite. For thermal analysis, a cold irritant (0 degrees C) was applied on the outer surface of a metal-ceramic crown for 7 seconds. RESULTS: The metaldowel and core generated lower thermal stresses in the restorations and dentin than the nonmetallic dowel and cores. CONCLUSION: Stress level is closely related to the degree of thermal gradient. The nonmetallic dowel and cores generated greater thermal stresses than metaldowel and cores.
Authors: Tulimar P M Cornacchia; Estevam B Las Casas; Carlos Alberto Cimini; Rodrigo G Peixoto Journal: Med Biol Eng Comput Date: 2010-07-16 Impact factor: 2.602