Dentinal tubule morphology in carious lesions: A confocal microscopic study

Abstract

Objective: The present study was designed to analyze the morphology of dentinal tubules in carious lesions using confocal microscopy. Materials and Methods: Undecalcified ground sections of human teeth were stained with alizarin red and examined by confocal microscopy. Ten extracted carious teeth (premolar and molar) were collected, disinfected, and simultaneously fixed by storing the teeth in 10% formalin for 5 days. The specimens were later dehydrated and embedded in resin. Longitudinal and cross sections were cut, polished, and then stained with alizarin red. After dehydration, specimens were mounted on a glass slide and examined under confocal microscope using epi-fluorescent mode or transmission light mode at a wavelength of 512 nm. Results: The dentinal tubule morphology and the zones of dentinal caries were studied, and the histopathological changes of dentinal tubules showed areas of demineralized dentin, translucent dentin, and normal area. Conclusion: The current study showed that confocal laser scanning microscope has the ability to focus through a carious lesion into the underlying sound dentin and it is considered to be a nondestructive technique in demonstrating mineral changes in carious dentin.