The purpose of this study was to compare the effect of ferrule with different heights on the stress distribution of dentin
and the restoration-tooth complex, using the finite element stress analysis method. Three-dimensional finite element models
simulating an endodontically treated maxillary central incisor restored with an all-ceramic crown were prepared. Three-dimensional
models were varied in their ferrule height (NF: no ferrule, 1F: 1-mm ferrule, and 2F: 2-mm ferrule). A 300-N static occlusal
load was applied to the palatal surface of the crown with a 135° angle to the long axis of the tooth. In addition, two post
and core materials with different elastic modulus were evaluated. The differences in stress transfer characteristics of the
models were analyzed. Maximum stresses were concentrated on force application areas (32.6–32.8 MPa). The stress values observed
with the use of a 2-mm ferrule (14.1/16.8 MPa) were lower than the no-ferrule design (14.9/17.1 MPa) for both the glass fiber-reinforced
and zirconium oxide ceramic post systems, respectively. The stress values observed with zirconium oxide ceramic were higher
than that of glass fiber-reinforced post system. The use of a ferrule in endodontically treated teeth restored with an all-ceramic
post-and-core reduces the values of von Mises stresses on tooth-restoration complex. At rigid zirconium oxide ceramic post
system, stress levels, both at dentin wall and within the post, were higher than that of fiber posts.
Keywords Finite element analysis - Ferrule effect - All-ceramic anterior crown - Post–core - Stress distribution