Load-Bearing Capacity and Design Advantages of a Custom-Made, Thin Pure-Titanium Cranioplasty (CranioTop)

Abstract

Background: Adequate and stable coverage of cranial contour and continuity defects of any origin is a common challenge in neurosurgical clinics. This study presents the results of investigations concerning the mechanical load-bearing capacity and design advantages of custom-made implants made from a thin, pure-titanium sheet (CranioTop) (CLinstruments, Attendorn, Germany) for covering complex cranial defects. Methods: In 9 test series, the stability of three differently shaped and sized thin titanium sheet implants was tested using vertical, uniaxial compression with 3 different compression stamps, to investigate the behaviour of these implants in relation to punctiform as well as planar forces.Results: All 9 model implants showed elastic behavior in the synchronously recorded force/displacement diagrams at an impression of up to 2 mm. The forces at 2 mm deformation were between 170.1 and 702.7 Newton. Conclusion: Cranioplasty using CranioTop is a stable procedure for covering skull defects, even those of large dimensions. An added advantage is the significant reduction in effort required to prepare the area of the bone margins compared to other current techniques of cranioplasty.

A Comparative Study of Titanium Cranioplasty for Extensive Calvarial Bone Defects

“…For instance, PMMA can have unsatisfactory cosmetic outcomes in cases with large defects and lead to thermal damage to the brain parenchyma because of exothermic reaction during polymerization 32 . Hydroxyapatite is not recommended for use in the reconstruction of biomechanically stressed skulls because of its limited resistance to mechanical stress until the bone has completely grown into the defect 30,33 . The Ti6Al4V provided favorable biomechanical properties of durable strength and ductility.…”

“…Biomechanical resilience is the most important property for cranial reconstruction with alloplastic materials. 30 Although high mechanical loads are not usually applied to the skull bone, compared with the joints or extremities, cranial implants should have loading capacities to protect the brain parenchyma and bear the pressure difference between the air and the intracranial region. 31 Other alloplastic materials commonly used in cranioplasty, such as PMMA and hydroxyapatite, have several disadvantages over the titanium-based implant.…”

“…32 Hydroxyapatite is not recommended for use in the reconstruction of biomechanically stressed skulls because of its limited resistance to mechanical stress until the bone has completely grown into the defect. 30,33 The Ti6Al4V provided favorable biomechanical properties of durable strength and ductility. The density of a product manufactured by SLM of Ti6Al4V can be optimized by altering the process, such as laser power, laser scanning speed, and layer thickness.…”

Patient Satisfaction and Radiologic Assessability After Treatment of Complex Skull Defects With a Custom-Made Cranioplasty From a Thin Titanium Sheet

“…In addition, brain parenchyma—which may still be prolapsed—does not have to be compressed by inserting a thicker implant into the defect. The displacement and compression of the implant from external pressure, and the associated risk of brain damage, can be prevented by placing the titanium cranioplasty on the bone edges of the defect and fixing it with individual titanium screws 30 …”

A Hybrid Titanium-Softmaterial, High-Strength, Transparent Cranial Window for Transcranial Injection and Neuroimaging

“…Ideally, a hybrid metal-softmaterial cranial window may have both high mechanical strength and excellent transparency. Titanium (Ti) mesh is a typical metallic cranioplasty material for its excellent biocompatibility, high strength and perfect structural stability [ 64 , 65 , 66 , 67 , 68 , 69 , 70 ]. Meanwhile, PDMS is a soft material with high transmittance, biocompatibility, and penetrability [ 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 ].…”