A survey was conducted over a 3 month period in 1983 to examine the influence of clinical factors on the incidence of dry socket (DS) after extractions of permanent teeth under local analgesia. The findings were compared with those of a similar 3 month survey in the same hospital in 1971. Age, sex and extraction site each significantly influenced the incidence of DS. The major difference from the 1971 survey was an increase in the DS incidence from 3.0% to 4.0% of extractions. This occurred mainly following multiple extractions and may indicate that patients, particularly in this group, are nowadays less tolerant of any post-extraction discomfort and hence more readily return for attention. This is particularly relevant in the present study since the broad definition of DS used in both surveys embraced even the mildest presentations of disturbed socket healing.