3D printed PEEK skull implants have made remarkable achievements in the field of cranioplasty due to their superior performance and significant benefits.

 

3D Printed PEEK Cranial Implants: An Innovation in Cranioplasty

 

Goals of cranioplasty

 

The skull, one of the hardest bones in the human body, is responsible for protecting the brain, and when the skull is defective due to trauma, surgery, or congenital factors, the safety of the brain is seriously threatened. Cranioplasty is a crucial neurosurgical procedure for patients with skull defects, which aims to repair skull defects, restore the integrity of the cranial cavity, and rebuild a strong protective barrier for brain tissue.

 

The significance of cranioplasty for patients is self-evident. From a physiological point of view, it can effectively protect brain tissue, reduce the risk of secondary injury, and reduce various symptoms caused by skull defects, such as headache, dizziness, nausea, vomiting, etc., laying the foundation for the patient's physical recovery. From a psychological point of view, skull defects often affect the appearance of patients, which in turn leads to psychological problems such as low self-esteem and depression. Cranioplasty can improve a patient's appearance, help them regain their self-confidence and integrate into society. Especially for pediatric patients, cranioplasty also helps to promote the normal development of brain tissue, which is essential for its future growth and development.

 

The dilemma and limitations of traditional cranial repair materials
 

In the development of cranioplasty, many materials have been tried to be used for cranial repair, however, many problems and limitations have been gradually exposed in the practical application of these traditional materials, which have limited their clinical use to varying degrees.

 

Autologous bone

Autologous bone was once regarded as an ideal skull repair material, and it has incomparable biocompatibility, because it comes from the patient itself, so after implantation in the body, it basically does not cause immune rejection, creating good conditions for bone healing. At the same time, autologous bone can well replicate the original shape and structure of the skull, and perform well in terms of aesthetic effect, so that patients will not have obvious abnormalities in appearance.

 

However, autologous bone also has significant drawbacks. Obtaining autologous bone requires additional surgery, which will undoubtedly increase the surgical trauma and pain of the patient, and there may be complications such as pain and infection at the postoperative bone removal site. In addition, the supply of autologous bone is very limited, and for some patients with large skull defects, it is often not possible to provide sufficient bone mass to meet the need for repair. In addition, the texture and shape of the bone fragment may not be fully adapted to the skull defect, which requires the surgeon to spend a lot of time trimming and shaping during the operation, which increases the difficulty and duration of the operation. 

 

bone cement

Bone cement has also been used in skull repair, but its disadvantages are also prominent. Bone cement generates heat during the curing process, and if this heat is not well controlled, it may cause thermal damage to the surrounding brain tissue and affect nerve function. After surgery, bone cement is also prone to cause subcutaneous effusion, because it does not fit well with the surrounding tissues, and it is easy to form dead spaces, leading to fluid accumulation. Once subcutaneous fluid buildup, it not only increases the patient's discomfort, but can also lead to infection, further aggravating the patient's condition. Moreover, bone cement is brittle after molding, and it is easy to break when impacted by external forces, which greatly reduces its protective effect on the skull, so that patients need to be extra careful in daily life to avoid head collisions.

 

plexiglass

Plexiglass once had a place in the field of cranial repair, but with the deepening of clinical application, its shortcomings have become more and more obvious. Plexiglass is brittle, which means that it is extremely fragile when subjected to external forces and cannot provide reliable protection for the skull. At the same time, it has poor impact resistance, and it is difficult to withstand the minor bumps that may occur in daily life, and once the plexiglass is broken, it may pose a direct threat to brain tissue. In addition, plexiglass has poor histocompatibility, and after being implanted in the body for a long time, it may cause rejection in the body, resulting in local inflammation, pain and other symptoms, which seriously affects the quality of life of patients. Due to these defects, the use of plexiglass in clinical cranial repair has gradually decreased and has been largely replaced by other materials.

 

Medical silicone

Medical silicone has some limitations when it comes to cranial repair. From the perspective of fixation stability, the fit between the silicone and the skull is relatively poor, and the fixation is not firm enough, which is prone to displacement during the postoperative recovery process, which requires surgical adjustment again, which brings additional pain and economic burden to the patient. In addition, medical silicone also has the risk of inducing epilepsy, which may be related to the stimulation of surrounding brain tissue by silicone, which can interfere with the normal conduction of nerve electrical activity, thereby triggering seizures. For patients, seizures not only affect physical health, but also cause great psychological stress and reduce quality of life. These problems have greatly limited the application of medical silicone in skull repair.

 

Ceramic materials

Although ceramic materials have certain biocompatibility and good hardness, their poor brittleness and toughness seriously restrict their practical application in skull repair. In daily life, the head will inevitably be subjected to some slight external forces, and ceramic materials are easy to crack when exposed to these external forces due to their high brittleness, and cannot continue to provide effective protection for the skull. Moreover, its lack of toughness makes it difficult to shape and accurately match the shape of the skull defect, which affects the effectiveness and aesthetics of the repair. Therefore, although ceramic materials have certain advantages in some aspects, they are less widely used in the field of cranial repair due to their inherent defects.

 

Although traditional cranial repair materials have provided patients with treatment options for a certain period of time, their respective limitations have led clinicians and researchers to continuously seek more ideal materials to improve the effectiveness of cranioplasty and the quality of life of patients. Against this backdrop, 3D printed PEEK skull implants bring new hope to the field of cranial repair.

 

 

PEEK material characteristics:
 

PEEK material

PEEK is a high-performance special engineering plastic, from the perspective of biocompatibility, PEEK is non-toxic and non-irritating to human tissues, and will not trigger immune response or inflammation, which makes it able to live in harmony with surrounding tissues after implantation in the human body, reducing the risk of postoperative infection and rejection, and providing safety for the patient's recovery. In many clinical cases, patients who have used PEEK material for cranial repair have a good postoperative recovery and few adverse reactions caused by the material, which fully proves its excellent biocompatibility.

 

PEEK has high tensile strength, high elastic modulus, high hardness and excellent impact resistance in terms of mechanical properties, which can withstand various external forces on the head in daily life and provide reliable protection for the skull. Moreover, PEEK retains its high strength even at high temperatures, a characteristic that allows it to function stably in some special situations. For example, in high-temperature scenarios such as fires, PEEK implants continue to protect the brain without deformation or damage like some traditional materials.

 

Ray translucency is also an advantage of PEEK materials. PEEK does not produce metal artifacts when performing imaging tests such as CT and MRI, which makes it easier for doctors to clearly and accurately observe the patient's recovery after surgery. Through these examinations, doctors can detect whether there is a problem in the skull repair site in time, so as to adjust the treatment plan and improve the treatment effect.

 

PEEK also has good resistance to abrasion, corrosion, and radiation. Its abrasion resistance makes it not damaged by friction with surrounding tissues during long-term use; Corrosion resistance allows it to resist the erosion of human body fluids and other chemicals, and maintain stable performance; Radiation resistance ensures that it does not affect its own performance when it is treated with radiation sterilization of medical devices. These properties make PEEK an ideal choice for cranial implants.

 

 

Advantages of 3D printing PEEK
 

Perfect fit, precise repair

In practical clinical application, many patients have irregular shape of skull defects, and it is difficult for traditional materials to achieve the ideal repair effect. The combination of 3D printing technology and PEEK materials makes the precise customization of cranial implants a reality. Through the accurate acquisition and 3D modeling of the CT data of the patient's skull, the 3D printer is able to create PEEK implants that fit perfectly into the skull defect, which not only improves the success rate of the surgery, but also significantly improves the patient's postoperative comfort and visual satisfaction. Compared to traditional cranial repair materials, 3D printed PEEK implants do not require extensive trimming and shaping during surgery, reducing surgical time and patient trauma, making the surgical process more efficient and safer.

 

Future developments

 

3D printed PEEK skull implants have made remarkable achievements in the field of cranioplasty due to their superior performance and significant benefits. With the continuous development of technological improvement, cost reduction and application expansion in the future, it will surely play a more important role in neurosurgery and related fields, bring health and hope to more patients, and open a new chapter in the field of cranial repair.

 

Example of a 3D printed PEEK skull implant