An algorithm of facial aging: Verification of Lambros's theory by three-dimensional stereolithography, with reference to the pathogenesis of midfacial aging, scleral show, and the lateral suborbital trough deformity

An algorithm of facial aging is presented that sen es as the conceptual bas is for understanding aesthetic surgical principles and techniques. This mod el begins with the verification of Lambros's theory of skeletal remodeling. It was suggested that bony changes of the midface may be summarized as a cl ockwise rotation of the midface relative to the cranial base. Three-dimensi onal stereolithography/rapid prototyping was used to test this hypothesis. A precisely duplicated facial skeleton was created for young and old men (n = 12) by laser polymerization. Angular measurements confirmed that the ang le of the pyriform and maxilla decreased with age (p = 0.004 and 0.005, res pectively); there was a trend for the angle of the glabella (frontonasal an gle) and orbits to do the same. These results validate Lambros's theory, wh ich sen es as a basis to further comprehend the pathogenesis of midfacial a ging and the formation of ectropion and scleral show. The algorithm of facial aging is extrapolated from these data, from previou s research, and from clinical observation. This model encompasses three mai n concepts or tenets, and it may serve as a clinical tool for the diagnosis and treatment of facial aging.