@Article{, title={The shear bond strength of artificial teeth with denture bases}, author={Nabeel A.F. Hatoor and Hussain. N.A. Ali}, journal={Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد}, volume={22}, number={2}, pages={32-37}, year={2010}, abstract={ABSTRACT
Background: Fracture and deboning of artificial teeth from denture bases are common clinical problems which are
facing both the patient and the dentist. The optimal combination of artificial teeth with visible light cured (VLC)
denture base resin and the effect of thermocycling should be evaluated. This study was conducted to evaluate and
compare the shear bond strength of artificial teeth (acrylic and porcelain) with denture bases cured by water bath
and visible light under the effect of different surface treatments and the effect of thermocycling with artificial saliva.
Material and methods. Heat polymerized (Densply) and visible light polymerized (Elite) acrylic resins were used. Two
types of artificial teeth (acrylic, Florident) and (porcelain, Ivoclar vivadent) were prepared. Five specimens of each
tooth type were processed to each of the denture base materials after the application of different surface
treatments according to the manufacturer’s instructions. Five specimens for each type of artificial teeth without
surface treatments were also fabricated. Specimens were thermocycled and tested for strength until fracture with an
Instron universal testing machine. Data were analyzed with analysis of variance and student T-test. A
photomicrographic microscope was used to identify adhesive and cohesive failures within debonded specimens.
Results. The mean force required to fracture the specimens were obviously larger for heat cured specimens
compared with the light cured specimens. The most common failure was cohesive within the tooth or the denture
base. With each base material, the artificial teeth which were treated with combined mechanical and chemical
surface treatment exhibited the highest shear bond strength. Thermocyclig had deleterious effect on the light cured
specimens. In general, heat polymerized groups failed cohesively within the artificial tooth. While the light cured
groups failed adhesively at the tooth denture base interface.
Conclusions. Within the limitations of this study, the type of denture base materials and surface treatments of the
denture tooth selected for use may influence the shear bond strength of the tooth to the base. Selection of more
compatible combinations of base and artificial teeth may reduce the number of prosthesis fractures and resultant
repairs.
Key words: acrylic teeth, porcelain teeth, visible light cured denture base, thermocycling, acetone, thinner,
hydrofluoric acid, shear bond strength. (J Bagh Coll Dentistry 2010;22(2):32-37).

} }