title: Photoelastic stress analysis of different prefabricated post-and-core materials.
abstract: The purpose of this study was to investigate stress developed by a combination of a stainless steel post or a fiber-reinforced resin post with a silver amalgam core or a composite resin core. Two-dimensional photoelastic models were used to simulate root dentin.  Posts (ParaPost XT and ParaPost-FiberWhite) were cemented with a luting agent (RelyX Unicem).  Silver amalgam cores and composite resin cores were fabricated on the posts. Complete crowns were fabricated and cemented on the cores. Each model was analyzed with 2 force magnitudes and in 2 directions.  Fringe orders were recorded and compared using ANOVA (p=0.05) and the Scheffe's test. With vertical force, no stress differences occurred among the 4 groups (p=0.159). With a 30-degree force, there was stress differences among the 4 groups (p<0.001). The combination of a fiber-reinforced post and composite resin core could potentially reduce stresses within the radicular dentin when angled loads are applied.
authors.affiliation: Prosthodontic Residency Training Program, Faculty of Dentistry, Mahidol University, 6 Yothi St. Rajathevi, 10400, Bangkok, Thailand. dtpas@mahidol.ac.th
authors.forename: Pattapon
authors.initials: P
authors.lastname: Asvanund
authors.forename: Steven M
authors.initials: SM
authors.lastname: Morgano
mesh_terms: D002484:Cementation / Q000379:methods; D003188:Composite Resins / Q000737:chemistry; D003442:Crowns; D003722:Dental Alloys / Q000737:chemistry; D003723:Dental Amalgam / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D003804:Dentin / Q000033:anatomy & histology; D017220:Dentin-Bonding Agents / Q000737:chemistry; D004548:Elasticity; D006801:Humans; D008422:Materials Testing; D008953:Models, Anatomic; D010165:Palladium / Q000737:chemistry; D011176:Post and Core Technique / Q000295:instrumentation; D019279:Resin Cements / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D013193:Stainless Steel / Q000737:chemistry; D013314:Stress, Mechanical; D014092:Tooth Root / Q000033:anatomy & histology; D015036:Zinc Phosphate Cement / Q000737:chemistry
chemical_list: D003188:Composite Resins; D003722:Dental Alloys; D003764:Dental Materials; D017220:Dentin-Bonding Agents; C483522:LuxaCore; C483701:Rely X Unicem; D019279:Resin Cements; D013193:Stainless Steel; C033470:Dispersalloy; D012834:Silver; D010165:Palladium; D015036:Zinc Phosphate Cement; D003723:Dental Amalgam