Comparative Evaluation of Compressive Bond Strength between Acrylic Denture Base and Teeth with Various Combinations of Mechanical and Chemical Treatments

Abstract

Debonding and detachment of artificial teeth from the denture base is frequently encountered in prosthodontic practice. This study aims to assess the effect of modifications in the ridge-lap surface of denture teeth with various combinations of mechanical and chemical surface treatments with hydrofluoric acid on bond strength with the acrylic denture base resin and to identify the failure modes (adhesive, cohesive, or mixed). Seventy acrylic resin teeth samples were randomly divided into seven groups (n = 10): a control group (unmodified) and six treatment groups, in which various combinations of mechanical and chemical surface treatments were performed. Then, these teeth were attached to a heat-cured denture base resin block at 45° angulation. The acrylized test samples were thermocycled, and the compressive bond strength was evaluated using a universal mechanical testing machine. The results suggest that roughening with diamond burs yields the highest bond strength, whereas etching/grooving and air abrasion result in the lowest bond strength. Acid etching complemented air abrasion to improve bond strength, while negative effects were noted with acid etching in other groups. Furthermore, roughening at the neck portion of the acrylic teeth can be used by the manufacturing companies as a standard to provide higher bond strength while maintaining the esthetics of the anterior teeth.

Feldspar-Modified Methacrylic Composite for Fabrication of Prosthetic Teeth

“…Similar bond values of 20–30 N between acrylic teeth available on the market and the denture plate were also obtained by other authors, for the same number of tested samples [ 27 , 28 , 29 , 30 ]. However, special attention should be paid to the preparation of the tooth surface by extending its surface with burs and activating it with coupling agents, which has already been widely discussed in the literature on the subject [ 6 , 28 , 29 , 30 ].…”

“…Although there are different materials on the market used to make teeth for removable dentures (porcelain, composite), PMMA is the most frequently used material. Compared to porcelain teeth, teeth made of poly(methyl methacrylate) are less brittle, have better connection to the denture base material, are easier for occlusal adjustments and repolishing, have a more natural appearance, and create less chewing noise [ 4 , 5 , 6 , 7 ]. Various types of fillers can be added to the material to improve its mechanical properties, which can increase its hardness by causing abrasion [ 8 , 9 , 10 ].…”

Effect of Different Chemical Surface Treatments on the Shear Bond Strength of Acrylic Teeth With Different High-Impact Denture Base Resins

“…The chemical surface treatment was performed as follows: Subgroup 2, the ridge lap area was wetted with a mixture of dichloromethane and monomer (1:1 by volume) with a cotton tip applicator and left for 4 min for drying before packing; Subgroup 3, the ridge lap area was wetted with ethyl acetate with a cotton tip applicator, and left for 2 min; and Subgroup 4, the ridge lap area was wetted with a drop of cyanoacrylate adhesive. To simulate in vivo conditions, the test samples were subjected to 6000 cycles of thermocycling in distilled water between 5 °C and 55 °C, with a one-minute dwell time [ 1 ].…”

“…Replacement with artificial dentures is the most common treatment preferred by elderly individuals because of their low cost compared to implants and fixed prostheses. Acrylic teeth are usually preferred over porcelain teeth because they are chemically bonded to the denture base material, easily available, easily trimmed, and inexpensive [ 1 ]. The introduction of cross-linked acrylic teeth led to a further increase in their stain resistance, fracture, and abrasive resistance but reduced their bond strength with the denture base [ 2 ].…”