OCT- An Emerging Diagnostic Tool in Sensing Marginal Integrity of Nano Composites

Abstract

Objectives: The purpose of the present research was to demonstrate images of failure into the structure of nano composites using optical coherence tomography. Methods: Ten human third mandibular molars were taken in the study. A class V cavity was prepared and restored with nano composite universal. 20 OCT images of each tooth were obtained and a total of 200 images were evaluated after restoration. Spectral domain (SD-OCT), at 840 nm and a measured spatial resolution of 10 µm was used for the study, which is based on the Michelson interferometer set-up and is controlled by the software OCT 800 – Complex Square/LabView, that collects data and generates the image. The restored surfaces were scanned in a bucco-lingual direction and tomographic images were obtained. Later, the crown of each tooth was sectioned in a occlusogingival direction (buccolingually) and images of each section were obtained by a Stereo microscope. Images of OCT and stereo microscope were compared and evaluated. Results: Images obtained by OCT helped in identifying failures at surface and in the internal structure of composites. Significance: Images obtained from OCT helps in detecting the failures, gaps, bubbles which adversely effect the longevity of restoration.