The aims of the present study were: (i) to identify the association of patterns of congenitally missing teeth with combinations of ectodermal symptoms occurring in patients with oligodontia; and (ii) to propose a diagnostic scheme for the general practitioner.

For this study 167 patients with oligodontia, both isolated and as part of a syndrome, and 135 healthy controls were interviewed and documented. Chi-square tests, logistic regression and correspondence analysis were used to evaluate and test differences between the groups and associations between the congenitally missing teeth and ectodermal symptoms.

No significant differences were found between the control group and the patients with isolated oligodontia with exception of the skin. It could be concluded from the present study that there were no clear associations between congenitally missing teeth, either individually or patterns, and the ectodermal symptoms or combinations of ectodermal symptoms.

However, it could be concluded that if the most stable teeth are missing, or if the number of missing teeth is large the patient should be examined carefully for symptoms of ectodermal dysplasia.

Using logistic regression a patient could be classified as having isolated oligodontia or oligodontia as part of a syndrome with a specificity and sensitivity of 88.2%.