title: Experimental polyethylene-hydroxyapatite carrier-based endodontic system: an in vitro study on dynamic thermomechanical properties, sealing ability, and measurements of micro-computed tomography voids.
abstract: The dynamic thermomechanical properties, sealing ability, and voids formation of an experimental obturation hydroxyapatite-reinforced polyethylene (HA/PE) composite/carrier system were investigated and compared with those of a commercial system [GuttaCore (GC)]. The HA/PE system was specifically designed using a melt-extrusion process. The viscoelastic properties of HA/PE were determined using a dynamic thermomechanical analyser. Human single-rooted teeth were endodontically instrumented and obturated using HA/PE or GC systems, and then sealing ability was assessed using a fluid filtration system. In addition, micro-computed tomography (μCT) was used to quantify apparent voids within the root-canal space. The data were statistically analysed using one-way anova and post hoc tests. The HA/PE composite exhibited important modulus and damping changes with an increase of temperature. The HA/PE system was more flexible than GC as the modulus of GC appeared to be significantly higher than that of HA/PE as a result of the high positive glass transition temperature (Tg ). However, HA/PE and GC presented similar sealing abilities. In conclusion, because sealing ability and voids formation were comparable between the tested materials, the experimental HA/PE system may be considered a suitable alternative material for root-canal obturation. Moreover, HA/PE possesses specific viscoelastic behaviour and lower melting points, which may facilitate root-canal retreatments.
authors.affiliation: Department of Conservative Dentistry, College of Dentistry, Baghdad University, Baghdad, Iraq.|Department of Conservative Dentistry, King's College London Dental Institute, London, UK.
authors.forename: Raghad A
authors.identifier: 0000-0002-8752-9139
authors.initials: RA
authors.lastname: Alhashimi
authors.affiliation: Department of Conservative Dentistry, King's College London Dental Institute, London, UK.
authors.forename: Francesco
authors.initials: F
authors.lastname: Mannocci
authors.affiliation: Departamento de Odontologia, Facultad de Ciencias de la Salud, Universidad CEU-Cardenal Herrera, Valencia, Spain.
authors.forename: Salvatore
authors.identifier: 0000-0002-2527-8776
authors.initials: S
authors.lastname: Sauro
mesh_terms: D003763:Dental Leakage; D017886:Durapatite; D005898:Glass; D006801:Humans; D020959:Polyethylene; D012387:Root Canal Filling Materials; D012389:Root Canal Obturation; D055114:X-Ray Microtomography
chemical_list: D012387:Root Canal Filling Materials; D020959:Polyethylene; D017886:Durapatite
keywords: endodontic materials; fluid filtration; obturation; polyethylene/hydroxyapatite composite; μ
  CT