In a medical or academic context, an "index" is a scoring system used to assess oral health. If you are looking for a specific "piece" or paper from 2007, it may involve:

Paper Title: Evaluating the PUFA Index (2007) in the Assessment of Untreated Dental Caries Since its introduction in 2007, the PUFA index

The film draws from ancient folklore found in various cultures (most notably Indigenous Australian and Māori traditions) regarding the "vagina with teeth." In myths, this is often a hazard to be removed by a hero. In Teeth , the film subverts this: the "hero" (Dawn) does not remove the teeth; she accepts them as part of her agency.