Bone quality assessment around dental implants in cone-beam computed tomography images: effect of scan mode and metal artefact reduction tool.

Abstract

Objectives: The purpose of this study was to evaluate how artefacts caused by titanium and zirconia dental implants affect the bone quality assessment in CBCT images. The effect of scan mode and the use of metal artefact reduction algorithm (MAR) on artefacts suppression were taken in consideration.

Methods: Titanium and zirconia dental implants were installed in porcine bone samples and scanned with two CBCT devices with adjustments on scan mode and with the use of MAR. Control group consisted of bone sample without implant and scanned with full rotation scan mode without MAR. Artefacts extension was measured by deviation of gray values and bone quality around implants was measured by bone histomorphometry measurements (trabecular volume fraction, bone specific surface, trabecular thickness, and trabecular separation). Mean difference among groups was assessed by within ANOVA with Bonferroni correction. Correlation between bone quality measurements acquired in experimental and control groups were assessed by Spearman correlation test (α = 0.05).

Results: No statistical difference was found for artefacts extension in images acquired by half and full-rotation mode (p = 0.82). The application of MAR reduced artefacts caused by titanium and zirconia dental implants, showing no statistically significant difference to the control group (Titanium: p = 0.20; Zirconia: p = 0.31). However, bone quality measurements did not correlate to the control group (p < 0.05).

Conclusions: Bone quality assessment was affected by the presence of artefacts caused by dental implants. Scan mode did not affect the appearance of artefacts and did not affect the bone qualitative measurements. MAR was able to decrease artefacts, however, it did not improve the accuracy of bone quality measurements.