title: Survival rate and fracture strength of incisors restored with different post and core systems and endodontically treated incisors without coronoradicular reinforcement.
abstract: This in vitro study evaluated the survival rate and fracture resistance of maxillary central incisors restored with different post and core systems. The post and core systems investigated were a prefabricated high precious metal post with cast core (group A), zirconia post with a prefabricated bonded ceramic core (group B), and a resin-ceramic interpenetrating phase composite post (experimental) with a prefabricated bonded ceramic core (group C). The all-ceramic copings were cemented using Panavia 21 TC. In the group without coronoradicular reinforcement, the access cavity was closed with a light-cured composite in combination with a dentine-bonding agent (group D). Each specimen was intermittently loaded and thermocycled before final stress tests in a Zwick machine. The survival rates after 1,200,000 cycles in the artificial mouth were 90% (group A), 80% (group B), 60% (group C), and 100% (group D). Statistically significant differences were found between all groups with the exception of A and B, when failure during cyclic loading was included (Kruskal-Wallis multiple comparisons test). Samples restored with a cast post and core demonstrated more vertical root fractures. It was concluded that the preservation of both internal and external tooth structure is of utmost importance when restoring endodontically treated teeth.
authors.affiliation: Department of Endodontics, Henry M. Goldman School of Dental Medicine, Boston University, Massachusetts 02118, USA.
authors.forename: Oliver
authors.initials: O
authors.lastname: Pontius
authors.forename: D
authors.initials: D
authors.lastname: Nathanson
authors.forename: R
authors.initials: R
authors.lastname: Giordano
authors.forename: H
authors.initials: H
authors.lastname: Schilder
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Hutter
mesh_terms: D002484:Cementation; D002516:Ceramics / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D000044:Dental Abutments; D003764:Dental Materials / Q000737:chemistry; D017267:Dental Prosthesis Design; D003799:Dental Stress Analysis / Q000295:instrumentation; D017220:Dentin-Bonding Agents / Q000737:chemistry; D006047:Gold Alloys / Q000737:chemistry; D006801:Humans; D007180:Incisor / Q000503:physiopathology*; D008437:Maxilla; D010710:Phosphates / Q000737:chemistry; D011176:Post and Core Technique / Q000145:classification / Q000295:instrumentation; D019279:Resin Cements / Q000737:chemistry; D012390:Root Canal Therapy; D018709:Statistics, Nonparametric; D013314:Stress, Mechanical; D013499:Surface Properties; D015996:Survival Rate; D013816:Thermodynamics; D014082:Tooth Fractures / Q000503:physiopathology*; D014092:Tooth Root / Q000293:injuries / Q000503:physiopathology; D019553:Tooth, Nonvital / Q000503:physiopathology*; D015040:Zirconium / Q000737:chemistry
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; D006047:Gold Alloys; C093719:Panavia TPN-S; D010710:Phosphates; D019279:Resin Cements; D015040:Zirconium; C028541:zirconium oxide