Spiral scanning imaging and quantitative calculation of the 3-dimensional screw-shaped bone-implant interface on micro-computed tomography

Abstract

PurposeBone-to-implant contact (BIC) is difficult to measure on micro-computed tomography (CT) because of artifacts that hinder accurate differentiation of the bone and implant. This study presents an advanced algorithm for measuring BIC in micro-CT acquisitions using a spiral scanning technique, with improved differentiation of bone and implant materials.MethodsFive sandblasted, large-grit, acid-etched implants were used. Three implants were subjected to surface analysis, and 2 were inserted into a New Zealand white rabbit, with each tibia receiving 1 implant. The rabbit was sacrificed after 28 days. The en bloc specimens were subjected to spiral (SkyScan 1275, Bruker) and round (SkyScan 1172, SkyScan 1275) micro-CT scanning to evaluate differences in the images resulting from the different scanning techniques. The partial volume effect (PVE) was optimized as much as possible. BIC was measured with both round and spiral scanning on the SkyScan 1275, and the results were compared.ResultsCompared with the round micro-CT scanning, the spiral scanning showed much clearer images. In addition, the PVE was optimized, which allowed accurate BIC measurements to be made. Round scanning on the SkyScan 1275 resulted in higher BIC measurements than spiral scanning on the same machine; however, the higher measurements on round scanning were confirmed to be false, and were found to be the result of artifacts in the void, rather than bone.ConclusionsThe results of this study indicate that spiral scanning can reduce metal artifacts, thereby allowing clear differentiation of bone and implant. Moreover, the PVE, which is a factor that inevitably hinders accurate BIC measurements, was optimized through an advanced algorithm.

Inaccuracy of buccal bone thickness estimation on cone‐beam CT due to implant blooming: An ex‐vivo study

“…When the buccal bone was thin enough to fall in this doubtful zone, it could not always be seen (see Figure a,b). This doubtful zone might be caused by other types of artefact, such as shadow, halo and blur artefacts (Choi, Choi, & Yeo, ). No influence of cortical bone thickness or jaw type could be observed on the visibility of the buccal bone in this doubtful area.…”

How image-processing parameters can influence the assessment of dental materials using micro-CT

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Bone Marrow Mesenchymal Stromal Cells (BMMSCs) Augment Osteointegration of Dental Implants in Type 1 Diabetic Rabbits: An X-Ray Micro-Computed Tomographic Evaluation

“…The µCT scanner used in our study (Skyscan 1172, Bruker µCT, Kontich, Belgium) used a round scanning technique to produce the BIC values ranging from 56 to 68%. In comparison, a spiral Nano-CT scanner (Skyscan 1275, Bruker µCT, Kontich, Belgium) could have produced images with lesser artifacts and values 2%-4% lower than round scan [57]. The BIC measured by different techniques may produce different values.…”