Abstract
On the occlusal surface where a CAD/CAM inlay is placed, a cement line, referred to as a “butt joint,” exists at its margin. The long-term stability of this cement line is one of the critical factors influencing the prognosis of the restoration.
The present study aimed to investigate a coating material that would satisfy the following four requirements: 1） No color change after application, 2） Film thickness that does not affect occlusion, 3） Adhesion to tooth structure, resin cement, and CAD/CAM restorative material, and 4） Sufficient wear resistance. To evaluate these conditions, the following tests were conducted: 1） Color stability test, 2） Film thickness measurement, 3-1） Shear bond strength test, 3-2） Tensile bond strength test, 4-1） Wear resistance test, and 4-2） Three-body wear test.
The results showed that, in comparison to specimens without coating, application of the dental coating material significantly reduced the degradation of the cement line, suggesting that surface coating would be effective for protecting the cement line in CAD/CAM inlays.
