Evaluation of artifacts generated by titanium, zirconium and titanium–zirconium alloy dental implants in MRI, CT and CBCT images: A phantom study

Publication date: Available online 7 February 2019

Source: Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology

Author(s): Husniye Demirturk Kocasarac, Gulbahar Ustaoglu, Seval Bayrak, Rujuta Katkar, Hassem Geha, S. Thomas Deahl, Brian L Mealey, Murat Danaci, Marcel Noujeim

Abstract

Objective

To assess artifacts generated by zirconium, titanium, and titanium–zirconium alloy implants on MRI, CT, and CBCT, and to correlate the findings to the dose-area product and exposure factors on CT and CBCT.

Study Design

Three phantoms were built by embedding zirconium, titanium, and titanium-zirconium implants in ultrasound gel. MRI, CT, and CBCT were acquired using multiple sequences and settings. For MRI, the artifact was described as the length of signal void beyond the limits of the implant. For CT and CBCT, the artifact was calculated by subtracting the gray level of the darkest pixel from the level of the lightest pixel.

Results

In MRI, zirconium implants had minor distortion artifacts while titanium and titanium-zirconium implants created extensive artifacts (p< 0.05). In CT and CBCT, artifacts were less prominent with titanium and titanium-zirconium implants than zirconium (p< 0.05). Titanium grade 5 implants with 0.3 and 0.4 mm³ voxels produced the least severe artifacts.

Conclusions

MRI images were less affected by the artifacts from zirconium implants while CT and CBCT images showed less severe artifacts from titanium and titanium-zirconium alloy implants. CT generated greater artifacts than CBCT. Larger CBCT voxel sizes reduced dose-area product and the severity of artifacts.

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