Composition and Mechanical Properties of Gutta-Percha Endodontic Points

Abstract

Gutta-percha endodontic filling points were found to contain approximately 20% gutta-percha (matrix), 66% zinc oxide (filler), 11% heavy metal sulfates (radiopacifier), and 3% waxes and/or resins (plasticizer). The mechanical properties were indicative of a partially crystalline viscoelastic polymeric material. They were found to obey Hooke's law and displayed a prominent upper and lower yield point when stressed beyond the proportional limit. The essential differences in mechanical properties of individual brands were found to be a function of the gutta-percha and zinc oxide concentration.

Stress Distribution in Roots Restored with Fiber Posts and An Experimental Dentin Post: 3D-FEA

“…The mechanical properties of the materials (E and v) ( Tables 1-3) were transferred to the software Simpleware 4.1, based on literature data (10)(11)(12)(13) and the values calculated by the impulse excitation technique. All materials were assumed to be homogeneous, isotropic and linearly elastic; except for the glass and carbon fiber posts that were assumed as orthotropic, homogenous and linearly elastic.…”

Intraoral Temperature Triggered Shape-Memory Effect and Sealing Capability of A Transpolyisoprene-Based Polymer

“…Therefore, we sought to identify formulation parameters to alter the thermal properties of this polymer. In this study, TPI:100-S:0.5 was prepared as a standard material, with components and content ratios determined with reference to Ishii's report [31], to a study of SMP-2 [32] and to the components of commercial gutta-percha products for root canal filling material [23][24][25]. For TPI:100-S:0.5, the temperature at which the shape recovery ratio began to increase was 44 °C, and 100% shape recovery within 10 min was observed at over 52 °C (Figure 8).…”

Case report: retained gutta-percha as a cause for persistent maxillary sinusitis and pain

“…Gutta-percha, a product of tropical rubber plants, has been used since the mid-1800s as an endodontic filling material following root canal procedures 4 . The chemical structure of gutta-percha is a trans-isomer of poly-isoprene, or natural rubber; however it is more crystalline than natural rubber and often is formulated with medications such as zinc oxide, iodoform, chlorhexidine and calcium hydroxide, which contribute to both the antibacterial and antifungal activity 4– 7 .…”

“…The chemical structure of gutta-percha is a trans-isomer of poly-isoprene, or natural rubber; however it is more crystalline than natural rubber and often is formulated with medications such as zinc oxide, iodoform, chlorhexidine and calcium hydroxide, which contribute to both the antibacterial and antifungal activity 4– 7 . Animal studies have shown that gutta-percha becomes encapsulated by fibrous connective tissue with little inflammatory reaction 8 .…”