Correlation between micro-hardness and mineral content in healthy human enamel.

A Akkus,D Karasik,R Roperto

doi:10.4317/jced.53345

Abstract

BackgroundEnamel is the hardest and the stiffest tissue in the human body. The enamel undergoes multidirectional stresses, withstands multimillion chewing cycles, all while protecting the internal dentin and pulp from damage due to mechanical overload and exposure to the harsh chemical environment of the mouth. Raman spectroscopy allows to study enamel mineral content in a non-destructive and site-specific way. While Raman spectroscopy has been applied in other studies to assess tooth mineralization, there are no studies that examine the relationship between micro-hardness and mineral content of the untreated enamel. An understanding of this relationship is extremely important in a clinical context. The effect of various agents on enamel hardness was investigated, though the relationship between healthy enamel mineral content and micro-hardness remains obscure.Material and MethodsTwenty human incisor teeth were obtained in compliance with the NIH guidelines and imaged site-specifically with a Raman microscope and evaluated with a Brinell hardness measurement device. The front portion of each tooth was divided into apical, medium and cervical regions and subsequently imaged with a Raman microscope in these three locations. Results and ConclusionsThe results demonstrated that enamel mineral content varies significantly between individuals and is correlated with the hardness of the enamel. Non-invasive, sample preparation free Raman spectroscopy was successfully employed to measure the mineral content of healthy enamel and it correlated the mineralization score to the hardness measurements of the selected cervical location. The overall level of enamel mineral content may serve as a robust predictor of patients’ susceptibility to developing caries, and overall enamels wear resistance, thus allowing for the prevention of caries via clinically available methods of remineralization, fluoride treatment and frequent cleaning. Key words:Enamel, raman spectroscopy, micro-hardness, extracted teeth.

Highlights

Enamel is the hardest and the stiffest tissue in the human body
While Raman spectroscopy has been applied in the literature to assess tooth mineralization, there are no studies that examine the relationship between micro-hardness and mineral content of the untreated enamel
When the measurements were pooled within the cervical region, incisor hardness varied dramatically depending on the region (Fig. 3)

Summary

Introduction

Enamel is the hardest and the stiffest tissue in the human body. Dental enamel is 95% mineral, 1% organic matter and 4-5% water by weight percentage [1]. While Raman spectroscopy has been applied in the literature to assess tooth mineralization, there are no studies that examine the relationship between micro-hardness and mineral content of the untreated enamel. An understanding of this relationship is extremely important in a clinical context, for tooth handling in vivo and structure property research inquiry of extracted teeth. While Raman spectroscopy has been applied in other studies to assess tooth mineralization, there are no studies that examine the relationship between micro-hardness and mineral content of the untreated enamel An understanding of this relationship is extremely important in a clinical context. The overall level of enamel mineral content may serve as a robust predictor of patients’ susceptibility to developing caries, and overall enamels wear resistance, allowing for the prevention of caries via clinically available methods of remineralization, fluoride treatment and frequent cleaning

Results

Discussion

Conclusion