Increased knowledge is shedding new light on our understanding of cent
ral and peripheral nerve anatomy and molecular biology and function. N
ew tools and methods provide important methods for the study of the be
havior of cells, axons, and receptors. This review discusses the curre
nt state of that knowledge, with particular regard to the efficacy of
the Seddon classification of nerve injury. The correlation of that new
information to damage and repair of the peripheral sensory nerve, esp
ecially the inferior alveolar and lingual nerves, serves to highlight
the progress and problems that exist.