Abstract
Purpose: Studying the effect of surface roughness and thermal cycling on titanium–ceramic bonding.
Methods: One hundred fourteen samples in the form of bar for the C.P. titanium and Ti–6Al–4V alloy were used. They were divided into two groups according to the type of bar. Each group was then subdivided according to the type of surface treatment to three subgroups, control, airborne-particle abrasion and silica coated. Each subgroup was subdivided into two classes according to the type of test (surface roughness and bond strength). Samples used for the bond strength test were veneered. These samples were subdivided into two subclasses according to thermal cycling; whether without thermal cycling or after 6000 thermal cycles.
Results: The surface roughness test results showed that silica coating recorded the highest surface roughness. Also C.P. titanium gave higher value of surface roughness than Ti–6Al–4V alloy. As regard the bond strength, the airborne-particle abrasion classes and the silica coated classes recorded bond strength values above the acceptable limit of 25 MPa determined in ISO 9693. As regard thermal cycling, the results showed that aging by thermal cycling decreased the metal–ceramic bond strength.
Conclusions: The airborne-particle abrasion and the silica coating are acceptable treatments for titanium–ceramic restorations. Increasing surface roughness of C.P. titanium and Ti–6Al–4V alloy not necessarily results in an increase in their bond strength to ceramics. Aging affects the metal–ceramic bond strength.