This study examined the relationship of dental students' (N=145) perceptions of how much control they have over their environments to their academic achievement and to such demographic variables as age, gender, race, or ethnicity. Subjects were given a questionnaire to obtain demographic information and Rotter's Internal-External Locus of Control Scale. Results indicated that the students tended toward an external locus of control. There were no statistically significant differences between the demographic variables and locus of control. The study did find a statistically significant relationship between locus of control scores and preclinical grades, with students classified as internally oriented achieving higher preclinical course grades than those classified as externally oriented. A table lists locus of control scores for age and gender. (Contains nine references.) (CH)