Accuracy of an electrical impedance device in estimation of remaining dentin thickness vs cone beam computed tomography.

The objective of this study is to compare the estimated values of remaining dentin thickness (RDT) recorded by a newly introduced electrical impedance device (Prepometer) with cone beam computed tomography (CBCT) and histological in situ measurement. A total number of thirty human molars were used in this study. A deep class I cavity was prepared. The RDT for each cavity was measured with Prepometer in three different points (mesial, middle, and distal). Same specimens were imaged with high-resolution Cone Beam Computed Tomography CBCT (0.1 mm voxel size) using I CAT next Generation Machine (Imaging Science International, Hatfield, PA, USA), to provide the highest possible accuracy of linear measurements. Finally, the specimens were vertically sectioned parallel to the long axis of the tooth in a mesiodistal direction splitting the cavity into two halves through its center. Then, the actual RDT of each half will be measured in the same three points using a digital caliper. The outcome of one-way ANOVA revealed that there was no significant difference in RDT values measured by prepometer device, CBCT, or histological sectioning methods (p > 0.05). Within the limitations of this laboratory study, prepometer seems to be a potential non-invasive accurate measuring tool for RDT. Based on the findings of this study, the Prepometer can be considered as an easily handled and less-expensive method compared to CBCT to evaluate the RDT. Also, it can be used in dental schools and with less-experienced operators to avoid traumatic exposures of the dental pulp.

Carboxymethyl cellulose acetate butyrate: a review of the preparations, properties, and applications.

Carboxymethyl cellulose acetate butyrate (CMCAB) has gained increasing importance in several fields, particularly in coating technologies and pharmaceutical research. CMCAB is synthesized by esterification of CMC sodium salt with acetic and butyric anhydrides. CMCAB mixed esters are relatively high molecular weight (MW) thermoplastic polymers with high glass transition temperatures (Tg). CMCAB ester is dispersible in water and soluble in a wide range of organic solvents, allowing varied opportunity to the solvent choice. It makes application of coatings more consistent and defect-free. Its ability to slow down the release rate of highly water-soluble compounds and to increase the dissolution of poorly soluble compounds makes CMCAB a unique and potentially valuable tool in pharmaceutical and amorphous solid dispersions (ASD) formulations.