Final answer:
Complex restorations are cases that need an extended time frame for completion and require a high level of technical skill from the restorative artist. They often involve meticulous dental work or facial reconstruction.
Step-by-step explanation:
Those restorative cases requiring a long period of time for completion and a high degree of technical skill on the part of the restorative artist are known as complex restorations. These cases typically involve extensive dental work or facial reconstruction, where precision and aesthetic considerations are paramount. In these scenarios, the individual tasked with the restoration must possess a sophisticated understanding of anatomy, artistry, and the materials involved.
In complex restorative cases, the outcome depends greatly upon the skill and expertise of the professional, making attention to detail and perseverance key elements of the process. These cases often require multiple procedures and appointments, as well as collaboration with other dental or medical professionals to achieve the desired results.