Dentifrice usage studies were made in a group of 44 Edinburgh children aged between 3 and 6 years using a gravimetric technique based on the polishing agent in the dentifrice. The amount of paste apparently swallowed during brushing averaged 0.5 g or less for 70% of the subjects; the worst performer apparently swallowed an average of 1.16 g per brushing. In contrast to previous studies employing a urinary or faecal marker which will underestimate the amount ingested if samples are lost, the present technique will overestimate the amount ingested under these circumstances. Hence the true picture probably lies between the two sets of results.

A test group of 22 subjects who had been taking non‐steroidal anti‐inflammatory drugs for periods in excess of one year were matched with a control group of 22 office workers with reference to age and Plaque Index. It was found that the test group had significantly lower values of Gingival Index and shallower depths of pockets than the control group of subjects. There was a trend also for there to be less loss of attachment in the test group. These results were interpreted as indicating that anti‐inflammatory drugs may influence the response of the periodontal tissues to plaque by reducing the prostaglandin concentration in the tissues. The slight decrease in loss of attachment in the test group may also be explained by the reduction in prostaglandin synthesis in the subjects taking anti‐inflammatory drugs.