Here is the thing about dental school. Mostly everyone is an intellectual hard working individual. Now the problem is, some people will decide that they have made it to dental school and what difference does it make if they bust their butts studying hard for a biochem exam or if they take it easy , learn the material and do average? For some people it matters cause they wanna specialize "about 20%" for the 80% it doesn't make a difference cause it doesn't affect their success as dentists. Thus, There is probably a correlation in the "rank's potential" but you will see some irrelevance in many cases.
What im saying is, if you want to specialize then you will work hard. If you want to be a general practitioner then there are two categories. One is you will still work hard. Two "which is about 50% of the class usually" You will still do decent but you will not bust your ass; you will not be completely dedicated especially when it comes to non clinical classes. This usually leads to a grade distribution that is not too much related to your DAT scores.
I went and looked up the answer to my own question.
J Dent Educ. 2006 Mar;70(3):258-62. Links
Dental Admission Test scores and performance on NBDE Part I, revisited.Bergman AV, Susarla SM, Howell TH, Karimbux NY.
Harvard School of Dental Medicine, Office of Dental Education, 188 Longwood Avenue, Boston, MA 02115, USA.
The purpose of this study was to examine the relationship between performance on the Dental Admission Test (DAT) and Part I of the National Board Dental Examination (NBDE Part I) for students at the Harvard School of Dental Medicine (HSDM). This study was a retrospective cohort study, examining HSDM students over an eight-year period. Data regarding DAT and NBDE Part I scores were obtained from the Office of the Registrar. Descriptive statistics were computed for all study variables. Multiple linear regression analyses were subsequently computed to examine the relationship between DAT subtest scores and performance on NBDE Part I subtests. Goodness of fit for the models was evaluated using the R-squared value. Statistically significant associations were those with p-value =0.05. Data were available for 244 students who matriculated at HSDM during the period of 1995-2002. DAT reading comprehension scores were statistically significantly associated with performance on all four subsections of the NBDE Part I. DAT general and organic chemistry scores were associated with performance on the microbiology and pathology subtest of NBDE Part I. Performance on the perceptual ability test was associated with performance on the dental anatomy and occlusion subtest. Performance on the DAT reading comprehension subtest was the most reliable predictor of performance on the NBDE Part I. However, the variability in NBDE Part I scores is not accounted for significantly by variability in DAT scores.