CS MAR reveals pathology and reduces risk of misinterpretation

Carestream Dental’s CS 8100 3D features the CS MAR (Metal Artifact Reduction) technology, which drastically reduces metal artefacts caused by dental restorations, implants, and fillings. As discussed by Dr Hanke Faust in the following case, this feature can compare images dynamically to obtain a more accurate and advanced diagnosis.

Dr Hanke Faust

A 50-year-old patient with extended soft tissue swelling around teeth 43 and 44 came to the practice (Figs. 1-2). The patient reported no pain and irritability on the lesion but the panoramic image revealed multiple coronal and apical pathological findings (Fig. 3). An extraoral image was captured with the CS 8100 3D.

A CBCT volume was taken with a 150-micron resolution for further diagnostics using the FDK reconstruction, as well as the new CS MAR (Metal Artifact Reduction) algorithm, which greatly increased the spectrum of diagnostic possibilities. The 3D view revealed osteolysis (Fig. 4).

When comparing the panoramic images extracted from the 3D scan (Figs. 5-6), the image with CS MAR applied (Fig. 6) showed significantly lower artefacts caused by implants, fillings and dental crowns. Various pathological findings, such as apical brightening at teeth 15, 26, 37 and 47; coronal brightening at teeth 15 and 45; and osteolysis at 15, 43 and 44, were easily identified. For confirmation of the diagnosis, the transverse and horizontal planes were also examined in both FDK and with CS MAR applied (Figs. 7-11).

The artefacts shown in the FDK reconstruction consisted mainly of hardening, extinction, noise and motion artefacts.

Diagnosis

The osteolytic-pathogenic processes in 3D X-ray diagnostics were assessed preoperatively within the framework of the WHO classification of odontogenesis lesions:

  1. Neoplasms and other tumours of the odontogenic apparatus (benign/malign)
  2. Tumours and other lesions of the bone (osteogenic tumours, non-neoplastic bone lesions)
  3. Epithelial cysts (developmental or inflammatory)

There was a need to distinguish between giant cell granulomas, fibromas and ameloblastic fibromas, as well as other osteolytic tumours.

In this case, a polycystic ameloblastoma at teeth 43 and 44 was suspected. The displaced expulsion of the bone and degradation of the bone and teeth where the tumour had penetrated them were all typical clinical characteristics.

When comparing the two reconstructions, the CS MAR reconstruction clearly revealed radicular processes in teeth 37 and 47; the osteolysis at 43 and 44; a mesioperiodontal lightening; as well as a distal fracture line at tooth 45 (red arrows in Fig. 13).

Using CS MAR in the CS 3D Imaging software allowed for more advanced diagnostics while decreasing the chance of misidentifying artefacts with moiré patterns and motion artefacts. For example, several implants (34, 35, 36) in the FDK reconstruction caused a strip-like hardening and extinguishing artefacts that made it hard to make a diagnosis. When applying CS MAR, the hardening and artefacts were significantly reduced. With the aid of CS MAR, the suspicion of root canal fracture was confirmed at tooth 45 (Fig. 14).

About the author

Dr Hanke Faust successfully completed an apprenticeship as a dental technician and studied at the University of Hamburg, Germany, where he also received his doctorate in dental studies with a focus on fully ceramic restorations. Instead of an in-university career, he decided early on to work in his own practice where he mainly focuses on aesthetic prosthetic care and the field of adhesive composite trusts. In addition to guided surgery, Dr Faust is particularly interested in radiological imaging using Carestream Dental imaging system. He has also written for and been published by the German Medical Publishers.

Continue reading here. Published in Dental Asia November/December 2021 issue.