The purpose of the investigation was to study the bond strength between silanized titanium specimens and poly(methyl methacrylate) (PMMA). The bond strength of silanized specimens joined together with PMMA was measured in 4-point bending tests in dry and wet conditions. The average bond strength of the specimens after dry storage at 37°C was 25 MPa. Water storage for 30, 60 or 90 days at 37°C reduced the bond strength to approximately 9–11 MPa. Infra-red spectroscopy analyses indicated that the adhesion between the silanized titanium interface and the polymer was due to chemical bonds.

Reference
Adhesion to titanium of methacrylate-based polymer materials.
Ekstrand K, Ruyter IE, Oysaed H.
Dent Mater. 1988 Jun; 4(3): 111-115.