In vitro and in vivo replication for scanning electron microscopy of the cervical region of human teeth

A replica technique for scanning electron microscopy (SEM) of the cervical region of human teeth was evaluated on extracted premolar teeth by comparing the replicas and the original specimens in the SEM. For in vivo application, the technique was modified to circumvent contamination by saliva and gingival exudate. Impressions were taken with an addition silicone polyvinylsiloxane material and the replicas were poured in epoxy resin die material. A surface active dentine conditioner facilitated flow of the impression material into irregular surface areas; in vivo a scavenger impression was used to remove surface debris. Custom trays were made of light-cured acrylic resin for the in vivo impressions. The method faithfully reproduced surface detail in the amelocemental region. In vivo the scavenger impression followed by application of the surface-active conditioner effectively cleaned the tooth surface. The custom tray allowed selection and inclusion of landmarks and ensured reproducibility. The method meets the requirements of a simple, reproducible, non-invasive means of documenting the micromorphology of the cervical region of the teeth.