To determine the functional position of labial, lingual and buccal frenii with the corresponding central incisor, premolar or molars in natural dentition.

20 dentate subjects between 20-40years of age were selected for the study. Maxillary and mandibular impressions were made and the distance from anterior attachment of frenum to the cusp tip of the corresponding tooth was measured.

The mean distance between the anterior attachment of labial frenum to the incisal edge of incisor was 12.25mm, the mean distance between the anterior attachment of buccal frenum of right side to cusp tip of corresponding teeth was 12.75mm and left side was 12.8mm and the mean distance between the anterior attachment of lingual frenum to incisal edge of incisor was 15.4mm. The coefficient of variation were 14.7%, 16.65%, 15.75% and 6.4% respectively.

The distance between the anterior attachment of the frenum to the cusp tips/incisal edges can be used as a pre-extraction record for determining the original vertical position of teeth.