Effect of specimen preparation on the appearance of the rat periodontal ligament in the scanning electron microscope

Abstract

The periodontal ligament, prepared in three different ways, was examined with the scanning electron microscope (SEM). Specimens prepared with an abrasive disc had an SEM appearance similar to that described by other workers, the periodontal space being largely occupied by an ‘indifferent fibre plexus’. Freeze-fracture surfaces and sections of demineralized material revealed a highly organised collagen fibre architecture. It was concluded that freeze-fracture and demineralizing methods disturbed the architecture less than grinding and therefore that the indifferent fibre plexus is an artifact of specimen preparation and that the ligament collagen is organised almost entirely as principal fibres.