Fructosamine assay is a new test used in the diagnosis and monitoring of diabetic patients. This assay may be of interest to the periodontist for, while the traditional plasma glucose value would give a general view and information about diabetic control at a certain point, the fructosamine concentration gives an indication of the plasma glucose level over a considerable period of time, such as 1 to 3 weeks. We investigated whether there was any relation between the diseased state of the periodontal tissues and plasma fructosamine and the plasma glucose values in non-insulin dependent diabetes mellitus (NIDDM) patients. We found that fructosamine correlated with the degree of gingival bleeding, however serum glucose levels had little or no correlation.