Restor Dent Endod.  2020 Nov;45(4):e45. 10.5395/rde.2020.45.e45.

A new phantom to evaluate the tissue dissolution ability of endodontic irrigants and activating devices

• Khoshroo K
• Shah B
• Johnson A
• Baeten J
• Barry K
• Tahriri M
• Ibrahim MS
• Tayebi L

• KMID: 2512036
• DOI: http://doi.org/10.5395/rde.2020.45.e45

Abstract

Objective
The aim of this study was to introduce a gelatin/bovine serum albumin (BSA) tissue standard, which provides dissolution properties identical to those of biological tissues. Further, the study evaluated whether the utilization of endodontic activating devices led to enhanced phantom dissolution rates.
Materials and Methods
Bovine pulp tissue was obtained to determine a benchmark of tissue dissolution. The surface area and mass of samples were held constant while the ratio of gelatin and BSA were varied, ranging from 7.5% to 10% gelatin and 5% BSA. Each sample was placed in an individual test tube that was filled with an appropriate sodium hypochlorite solution for 1, 3, and 5 minutes, and then removed from the solution, blotted dry, and weighed again. The remaining tissue was calculated as the percent of initial tissue to determine the tissue dissolution rate. A radiopaque agent (sodium diatrizoate) and a fluorescent dye (methylene blue) were added to the phantom to allow easy quantification of phantom dissolution in a canal block model when activated using ultrasonic (EndoUltra) or sonic (EndoActivator) energy.
Results
The 9% gelatin + 5% BSA phantom showed statistically equivalent dissolution to bovine pulp tissue at all time intervals. Furthermore, the EndoUltra yielded significantly more phantom dissolution in the canal block than the EndoActivator or syringe irrigation.
Conclusions
Our phantom is comparable to biological tissue in terms of tissue dissolution and could be utilized for in vitro tests due to its injectability and detectability.

Keyword

Tissue dissolution; Phantom; Endodontic irrigants; Gelatin; Bovine serum albumin

Figure

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  Figure 1 Dissolution (%) of the different phantoms at all time intervals.NaOCl, sodium hypochlorite.

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  Figure 2 (A) Fluorescence microscopy of the endodontic blocks that were instrumented with endodontic files and then irrigated using 3 different methods. (B) Tissue remaining (%) in the endodontic blocks that were irrigated using 3 different methods.*p < 0.05; †p < 0.001; ‡p < 0.0001.

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