Assessment of Restorative Materials in Deep Carious Lesions Using Incomplete Carious Lesion Removal Approach

Objectives: The objective of this study is to assess the efficacy of different restorative materials in deep carious lesions, following incomplete carious lesion removal technique in deep carious lesions using non-destructive 3D X-ray microtomography (XMT) and Energy Dispersive X-ray Spectroscopy (EDS) after six weeks.

Methods: A total of 82 extracted teeth with deep dental caries were assessed by the employment of the International Caries Risk and Assessment (ICDAS) criteria and radiographic evaluations. Eight teeth were selected according to inclusion and exclusion criteria. Each lesion was subsequently removed by leaving a thin layer of leathery type dentine at the deepest part of the cavity, close to the dental pulp. After placement of different restorative materials: Mineral Trioxide Aggregate (MTA), calcium hydroxide (CH), resin-based material (Activa Pulpdent), teeth were restored with the reinforced glass ionomer cement (GIC, Equia Forte). The teeth in the control group were restored using reinforced GIC alone. Each tooth was then placed in Simulated Body Fluid (SBF). The samples were immediately scanned and a further scan was performed after six weeks. The time taken for each scan was 24 hrs. The XMT images were reconstructed for each tooth to measure the loss/gain at the residual demineralised and restorative material sites. Subsequently, EDS mapping was performed for each sample.

Results: The XMT subtracted images clearly verified an increase in the Linear Attenuation Coefficient (LAC) within the leathery type residual dentine over six weeks. This increase in LAC was presented by an increase in radio-opacity, whilst radiolucent areas indicated a decrease in LAC. The reinforced glass ionomer cement had the largest increase in LAC followed by CH and MTA. Bioactive resin material failed to show any changes within the restorative material and residual carious dentine. EDS mapping also showed the GIC alone group had the most visual change when compared to the CH, MTA and resin-based material.


Conclusions: This laboratory-based study suggested that calcium, phosphate and strontium ions exchange at the residual demineralised dentine from GIC, MTA and Ca(OH)₂ in deep dentinal lesions following incomplete carious lesion removal for a period of six weeks.