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. 2020 Mar 19;9(3):832.
doi: 10.3390/jcm9030832.

Accuracy Assessment of Molded, Patient-Specific Polymethylmethacrylate Craniofacial Implants Compared to Their 3D Printed Originals

Dave Chamo  1   2 , Bilal Msallem  1   2 , Neha Sharma  1   2 , Soheila Aghlmandi  3 , Christoph Kunz  1 , Florian M Thieringer  1   2
Affiliations

Accuracy Assessment of Molded, Patient-Specific Polymethylmethacrylate Craniofacial Implants Compared to Their 3D Printed Originals

Dave Chamo et al. J Clin Med. .

Abstract

The use of patient-specific implants (PSIs) in craniofacial surgery is often limited due to a lack of expertise and/or production costs. Therefore, a simple and cost-efficient template-based fabrication workflow has been developed to overcome these disadvantages. The aim of this study is to assess the accuracy of PSIs made from their original templates. For a representative cranial defect (CRD) and a temporo-orbital defect (TOD), ten PSIs were made from polymethylmethacrylate (PMMA) using computer-aided design (CAD) and three-dimensional (3D) printing technology. These customized implants were measured and compared with their original 3D printed templates. The implants for the CRD revealed a root mean square (RMS) value ranging from 1.128 to 0.469 mm with a median RMS (Q1 to Q3) of 0.574 (0.528 to 0.701) mm. Those for the TOD revealed an RMS value ranging from 1.079 to 0.630 mm with a median RMS (Q1 to Q3) of 0.843 (0.635 to 0.943) mm. This study demonstrates that a highly precise duplication of PSIs can be achieved using this template-molding workflow. Thus, virtually planned implants can be accurately transferred into haptic PSIs. This workflow appears to offer a sophisticated solution for craniofacial reconstruction and continues to prove itself in daily clinical practice.

Keywords: 3D printing; PMMA; accuracy; additive manufacturing; craniofacial reconstruction; cranioplasty; molding; patient-specific implant.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
3D printed skull models with the defect area shown. (a) cranial defect (CRD); (b) temporo-orbital defect (TOD).
Figure 2
Figure 2
Comparison of the 3D printed templates (a,b, beige) with the patient-specific implants according to the n-point registration with five manually placed control points (c,d, purple), and the superimposition (e,f). Left: cranial template and PSI; right: temporo-orbital template and PSI.
Figure 2
Figure 2
Comparison of the 3D printed templates (a,b, beige) with the patient-specific implants according to the n-point registration with five manually placed control points (c,d, purple), and the superimposition (e,f). Left: cranial template and PSI; right: temporo-orbital template and PSI.
Figure 3
Figure 3
Descriptive data distribution illustrating the difference between the CRD-PSIs (models 1 to 10) and the CRD 3D printed template. (a) Mean difference ± SD (mm); (b) Median difference (Q1 to Q3) (mm).
Figure 4
Figure 4
Descriptive data distribution illustrating the difference between the TOD-PSIs (models 1 to 10) and the TOD 3D printed template. (a) Mean difference ± SD (mm); (b) Median difference (Q1 to Q3) (mm).
Figure 5
Figure 5
Box plot illustrating the accuracy comparison with respect to the root mean square (RMS) values (mm) between the polymethylmethacrylate (PMMA) CRD-PSI and TOD-PSI test groups (● describes the statistical outlier, CRD-PSI 01).
Figure 6
Figure 6
Color-coded deviation maps within each test group after applying the best-fit method and generating a 3D comparison to evaluate the accuracy. CRD-PSI: (a) squamous (outer) surface; (c) cerebral (inner) surface; TOD-PSI: (b) squamous (outer) surface; (d) cerebral (inner) surface.
See this image and copyright information in PMC

References

    1. Sorour M., Caton W.L., Couldwell W.T. Technique for methyl methacrylate cranioplasty to optimize cosmetic outcome. Acta Neurochir. 2014;156:207–209. doi: 10.1007/s00701-013-1800-3. - DOI - PubMed
    1. Lee C., Antonyshyn O.M., Forrest C.R. Cranioplasty: Indications, technique, and early results of autogenous split skull cranial vault reconstruction. J. Craniomaxillofac. Surg. 1995;23:133–142. doi: 10.1016/S1010-5182(05)80001-0. - DOI - PubMed
    1. Turgut G., Özkaya Ö., Kayali M.U. Computer-aided design and manufacture and rapid prototyped polymethylmethacrylate reconstruction. J. Craniofac Surg. 2012;23:770–773. doi: 10.1097/SCS.0b013e31824dbcaf. - DOI - PubMed
    1. Aydin S., Kucukyuruk B., Abuzayed B., Aydin S., Sanus G.Z. Cranioplasty: Review of materials and techniques. J. Neurosci. Rural Pract. 2011;2:162–167. doi: 10.4103/0976-3147.83584. - DOI - PMC - PubMed
    1. Gilardino M.S., Karunanayake M., Al-Humsi T., Izadpanah A., Al-Ajmi H., Marcoux J., Atkinson J., Farmer J.P. A comparison and cost analysis of cranioplasty techniques: Autologous bone versus custom computer-generated implants. J. Craniofac. Surg. 2015;26:113–117. doi: 10.1097/SCS.0000000000001305. - DOI - PubMed

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