Every tooth and restorative material have their own stress pattern recognizing them in vital to prior to designing a restoration without failure potential. Building a restoration is similar to building any mechanical structure in that the stress patterns of the available foundation and contemplated structure. Optimal functional capacity and stability of occlusal relationships are major considerations in every phase of restorative dentistry. Restoration not only mechanically replaces the lost part but, acts as a medium through which physical and mechanical forces are transmitted to the tooth and investing tissues. Each tooth has its own stress patterns. A thorough knowledge in dental materials is necessary to understand the physical properties including their response to stress. From this information obtained during the patient evaluation, the operator must envision the restoration replacing lost tooth structure being subjected to functional loading and then try to plan the best tooth preparation to both retain this restoration and make it resistant to these loads.