This study evaluated the effects of three modes of education on dentists' knowledge, attitudes, and use of pit and fissure sealants. A randomly selected group of dentists was invited to participate in a sealant education initiative. During a 12-month period, a total of 662 dentists either (1) attended continuing education courses, (2) received written materials and videotapes by mail, or (3) received only written materials by mail. A comparison group (n = 337) received no materials until after the education phase and evaluation had been completed. Pre- and postintervention surveys were used to measure changes in knowledge, attitudes, and sealant use. Response rates to the two surveys were 62 percent and 76 percent, respectively. Preintervention values for knowledge scores, an attitude scale, and sealant use were similar among the four groups. At followup, the three education groups had significantly higher knowledge scores than the comparison group. Attitude values for all but one group were not significantly different, and sealant use by all groups was identical. The numbers of respondents not using sealants declined slightly between surveys in the three education groups while rising slightly in the No-Education Group. Because program outcomes were similar to those of another sealant initiative, it can probably be concluded that continuing education will increase dentists' knowledge about sealants, but have little effect upon their attitudes or their use of the technique. The changes observed in this investigation may be due to the particular capacity for cognitive and affective changes of participants, characteristics of the technology being promoted, and external forces in the professional environment.