The document discusses various features of tooth preparations that enhance resistance and prevent dislodgement of dental restorations under forces. It describes how factors like preparation length, width, taper, presence of grooves or wings, and path of insertion can influence the resisting area and a restoration's ability to withstand lifting, tipping, and rotational forces. Shorter or more tapered preparations provide less resistance, while longer preparations or those with grooves/wings increase the resisting area and resistance to dislodging forces. The ideal path of insertion for a crown generally parallels the long axis of the tooth but may need to be perpendicular if the normal path is blocked.