Mechanical testing of indirect composite materials directly applied on implant abutments.

Autor: Andriani W Jr; Department of Prosthodontics, Universidade Federal de Santa Catarina, Florianopolis, Brazil., Suzuki M, Bonfante EA, Carvalho RM, Silva NR, Coelho PG
Jazyk: angličtina
Zdroj: The journal of adhesive dentistry [J Adhes Dent] 2010 Aug; Vol. 12 (4), pp. 311-7.
DOI: 10.3290/j.jad.a17710
Abstrakt: Purpose: To test the strength to failure and fracture mode of three indirect composite materials directly applied onto Ti-6Al-4V implant abutments vs cemented standard porcelain-fused-to-metal (PFM) crowns.
Materials and Methods: Sixty-four locking taper abutments were randomly allocated to four groups and were cleaned in ethanol in an ultrasonic bath for 5 min. After drying under ambient conditions, the abutments were grit blasted and a custom 4-cusp molar crown mold was utilized to produce identical crowns (n = 16 per group) of Tescera (Bisco), Ceramage (Shofu), and Diamond Crown (DRM) according to the manufacturer's instructions. The porcelain-fused-to-metal crowns were fabricated by conventional means involving the construction and a wax pattern and casting of a metallic coping followed by sintering of increasing layers of porcelain. All crowns were loaded to failure by an indenter placed at one of the cusp tips at a 1 mm/min rate. Subsequently, fracture analysis was performed by means of stereomicroscopy and scanning electron microscopy. One-way ANOVA at 95% level of significance was utilized for statistical analysis.
Results: The single load to failure (± SD) results were: Tescera (1130 ± 239 N), Ceramage (1099 ± 257 N), Diamond Crown (1155 ± 284 N), and PFM (1081 ± 243 N). Stereomicroscopy analysis showed two distinct failure modes, where the loaded cusp failed either with or without abutment/metallic coping exposure. SEM analysis of the fractures showed multiple crack propagation towards the cervical region of the crown below a region of plastic deformation at the indenter contact region.
Conclusion: The three indirect composites and PFM systems fractured at loads higher than those typically associated with normal occlusal function. Although each material had a different composition and handling technique, no significant differences were found concerning their single load to fracture resistance among composite systems and PFM.
Databáze: MEDLINE