Polymethylmethacrylate Cranioplasty Research Articles

A Single Standard Polyvinyl Chloride 3D Skull Model to Create the Polymethyl Methacrylate Cranioplasty Flap: A Novel and Low-Cost Technique.

Although, cranioplasty is a commonly performed neurosurgical procedure worldwide, the cost of available cranioplasty implants is a major issue in a low-income country like India. The aims of this study were to introduce a novel and low-cost technique using a single standard three-dimensional (3D) skull model to guide the polymethyl methacrylate (PMMA) cranioplasty flap production and to evaluate the functional and cosmetic outcomes. We retrospectively evaluated 47 cases of PMMA cranioplasty in the period from February 2019 to June 2022. A single standard 3D skull model was used to make the PMMA cranioplasty flaps. The overall cost of this PMMA implant was compared with that of other available cranioplasty implants. The functional and cosmetic outcomes were evaluated postoperatively. The mean age of our patients was 37.17 ± 13.83 years and the age range was 17 to 63 years. The primary cause of surgery was trauma in the majority of cases (n = 31, 65.96%). The mean operative time was 78.55 ± 19.82 minutes. The cosmetic results were very satisfying in 46 of 47 (97.87%) patients and moderately satisfying in 1 (2.12%) patient. Overall, there were three (6.38%) complications. Our technique provides excellent functional and cosmetic outcomes. The overall surgical cost of these PMMA implants was lower than that of the other available cranioplasty implants. This technique is currently the most cost-effective option for cranioplasty.

PMMA Cranioplasty Making by Using Open-Source CAD Software, PLA Printers, and Silicone Rubber Molds: Technical Note with Two Illustrative Cases.

We read with great interest Malikov et al's case report/technical note entitled “PMMA cranioplasty making by using open-source CAD software, PLA printers, and silicone rubber molds: technical note with two illustrative cases.”[1] We were the first in the literature to begin an ultra-low-cost patient-specific polymethyl methacrylate (PMMA) cranioplasty implant service in Pakistan, that too in a public sector hospital, and we have already published our technical note and limited case series with 1-year follow-up.[2] Since then, our technique has been adopted by our colleagues at neighboring centers, and we have amassed an experience of over 50 cases, and many of our patients are in long-term follow-up. At the national level, the lowest cost offered by commercial companies for a patient-specific PMMA implant exceeded US$ 1,000 and US$ 10,000 for titanium and polyetheretherketone (PEEK) hemicraniectomy implants, respectively. The vast majority of the Pakistani population are poor and underprivileged, and the trauma cohort who require this operation are actually those who could never meet these costs in their lifetime. Free-hand PMMA cranioplasty was utilized in virtually all cases nationally. After beginning our initial service, the total cost to manufacture an implant in consumables was US$ 40. The printer we used was a locally assembled Chinese Prusa i3 clone. Thus, production cost was exponentially cheaper than commercial rates, and in our experience, our clinical and aesthetic outcomes are the same, if not better. Naturally, when one intends to offer a service for the patient benefit rather than profit, affordability is one of the most important parameters, especially in the impoverished developing world. We would be delighted to know the exact specification of the printer used by Malikov et al, the cost of disposables and printing of each implant, and the context of this cost in their patient's socioeconomic demographic/health care system, and whether commercial options were as extortionate for their general public as it was for ours.

Early experience with patient-specific low-cost 3D-printed polymethylmethacrylate cranioplasty implants in a lower-middle-income-country: Technical note and economic analysis

Background: Polymethyl methacrylate (PMMA) cranioplasty, while widely prevalent, has limitations associated with freehand manual intraoperative molding. PMMA has been superseded by titanium or Polyetheretherketone implants, prefabricated commercially from preoperative CT scans, and boasting superior clinical and cosmetic outcomes. However, such services are extremely inaccessible and unaffordable in the lower-middle-income country (LMIC) settings. The study aims to describe, in detail, the process of making ultra-low-cost patient-specific PMMA cranioplasty implants with minimum resources using open-access software. We report the first such service from the public health-care system within Pakistan, a LMIC.Methods: Using open-source software, preoperative CT heads were used to prefabricate three-dimensional implants. Both implant and cranial defects were printed using polylactic acid (PLA) to assess the implant’s size and fit preoperatively. From the PLA implant, we fashioned a silicon mold that shapes the PMMA implant. Ten patients who underwent cranioplasty using our technique for various cranial defects with at least a 12-month follow-up were retrospectively reviewed. Clinical, cosmetic, and radiological outcomes were objectively assessed.Results: Etiology of injury was trauma (8), malignant MCA infarct (1), and arteriovenous fistula (1). We produced seven frontotemporal-parietal implants, one bifrontal, one frontal, and one frontoparietal. At 1 year, eight patients reported their cosmetic appearance comparable to before the defect. Radiological outcome was classified as “excellent” for eight patients. No postoperative complications were encountered, nor did any implant have to be removed. One patient’s implant involving the orbital ridge had an unsatisfactory cosmetic outcome and required revision surgery. The average cost per implant to the National Health Service was US$40.Conclusion: Prefabricated patient-specific PMMA cranioplasty implants are cost-effective. A single surgeon can fashion them in a limited resource setting and provide personalized medicine with excellent clinical/cosmetic-radiological results. Our method produces patient-specific cranioplasty implants in an otherwise unaffordable LMIC setting.

Microsurgical scalp reconstruction and cranioplasty refined

**Introduction** Microsurgical free flap scalp reconstruction is commonly the only reconstructive option in certain challenging patient cohorts. We describe the technical refinements that have streamlined our approach to microsurgical scalp reconstruction and cranioplasty. **Methods** Virtual surgical planning for multiple failed cranioplasty cases involves fashioning an implant with a 3 mm offset. Intramuscular dissection of the latissimus dorsi (LD) vascular pedicle, distal to its bifurcation, is routinely performed, and can increase pedicle length by up to 4 cm without the need for tedious dissection in the axilla. Anastomoses to the superficial temporal vessels distal to their bifurcation in the parietal scalp are reliable and safe. The sequence of surgery is in reverse to the conventional sequence, with the free flap vascularised before craniectomy/cranioplasty is performed to decrease the duration of synthetic implant exposure. **Results** Thirty-nine cases were performed in 35 patients over a five-year period. An LD-based free flap in various permutations was the commonest free flap option (n = 31). The superficial temporal artery and vein were choice recipient vessels in 82 per cent and 74 per cent of cases, respectively, with the former demonstrating higher anatomical consistency. Complications included free flap venous congestion successfully salvaged (_n_ = 1), infected polymethylmethacrylate cranioplasty requiring explantation (_n_ = 1), subdural haematoma requiring craniotomy for evacuation (_n_ = 1) and free flap donor site haematoma (_n_ = 2).**Conclusion**Our technical refinements offer a streamlined and reliable procedure of complex scalp reconstruction and cranioplasty.

Customized cost-effective polymethylmethacrylate cranioplasty: a cosmetic comparison with other low-cost methods of cranioplasty.

Intraoperative hand-moulded cranioplasty and polymethylmethacrylate (PMMA) prostheses made from bone impressions are economical but the cosmetic results are less than satisfactory. Commercially available customized prostheses perform better but are prohibitively expensive. We evaluate the performance of a locally developed, low-cost customized PMMA cranioplasty prosthesis. To compare the cosmetic outcome of 3 types of PMMA cranioplasty as well as with objective measurements on postoperative CT scans METHODS: This study includes 70 patients who underwent cranioplasty between March 2016 and June 2020. In this period, patients had their cranioplasty prostheses made by intra-operative hand moulding (HM), by using the removed bone as a template and making a bone impression (BI) or by 3D printing the prosthesis based on a CT scan. Cosmetic outcomes were assessed by the patient and the operating surgeon on an 8-point scale. The degree of measured anthropometric asymmetry was measured on a postoperative CT scan and correlated with the cosmetic outcome. Our locally produced 3D-printed cranioplasty prostheses showed a statistically better performance in cosmetic scores when compared to the HM and BI (p value < 0.001). CT anthropometric measurements significantly correlated with cosmetic outcome (p value 0.01) CONCLUSION: Our 3D cranioplasty prostheses had better cosmetic outcomes than HM and BI prostheses, and our technique is able to produce them at 10% of the cost of the currently available commercial customized prostheses.

Customized polymethylmethacrylate cranioplasty using a low-cost 3-dimensional printed mold

Introduction. Significant cranial defects result from a decompressive craniectomy following head trauma, malignant brain edema, intracranial hemorrhage, or resection of tumor affected bone. Unrepaired cranial defects are not just a tremendous esthetic problem. The underlying brain is unprotected, prone to injury, and this state can lead to the so-called ?syndrome of the trephined? with mood instability, headaches, and even a neurological deficit. Currently, there is no widely accepted uniform technique of cranial vault shape restoration. Combining 3D technology with the use of polymethylmethacrylate is a challenging field that can bring good functional and aesthetic results and, in the case of smart design, become efficient, low-cost technology. We offer a possible solution to a problem that would be acceptable in neurosurgical practice. Case outline. We present a 37-year-old male patient with a massive hemicranial defect as a consequence of previous decompressive craniectomy following severe craniocerebral injury the previous year. Together with engineers from the appropriate 3D modeling studio, we have designed a two-part mold by laser printing technology using biocompatible advanced polyamide. We made a customized polymethylmethacrylate graft intraoperatively using this mold and achieved good aesthetic results. Conclusion. Reports of 3D printing assisted cranioplasties are growing, describing different techniques and cost- estimation. We hope to introduce a low-cost and simple method for repairing a skull defect.

Patient specific Polymethyl methacrylate customised cranioplasty using 3D printed silicone moulds: Technical note.

IntroductionCranioplasty after decompressive craniectomy can be performed with several techniques and materials. With the common use of 3D printing, custom cranioplasty can be produced at affordable cost. Aim of this technical note is to describe our technique for producing patient specific Polymethyl methacrylate (PMMA) cranioplasty using 3D printed silicone moulds.Materials and MethodsWe enrolled seven patients from January 2020 to June 2021 who required surgery for cranioplasty. The 3D printing was used to produce silicone moulds for defining the exact shape of the PMMA cranioplasty, according to the CT scan of the patient.ResultsWe performed seven procedures. The mean time of the surgery was 80 min. All cranioplasties perfectly matched the patient specific anatomy. No complications occurred.ConclusionsUsing 3D printed patient specific silicone moulds and PMMA resulted to be effective, with affordable costs and ensuring a good cosmetic result.

Polymethylmethacrylate cranioplasty implant customized using a polylactic acid mold and prepared with a 3D printer: an example case

In recent years, the use of three-dimensional imaging and modeling methods has become increasingly frequent, replacing two-dimensional studies. Three-dimensional images, which are widely used in medicine, provide surgical facilities, especially in neurosurgical practice. Surgery for epilepsy, cranioplasty, vascular and intracranial lesions could be shaped based on three-dimensional images. The main purpose of cranioplasty is to replace bone tissue loss due to previous surgery or trauma to protect brain tissue. For this purpose, autologous grafts could be used as well as materials such as polymethylmethacrylate. In this study, a PLA mold was produced using a three-dimensional printer for the patient who was planned for cranioplasty and cranioplasty was performed with PMMA. The perioperative observation of the patient revealed that the mold was fully seated. The patient was satisfied cosmetically in the follow-up. With the advancement of technology, the use of three-dimensional printers in neurosurgery practice will further increase, individual treatment methods will be developed and better results will be obtained with less cost and complication rates.

Puzzling Technique for Fixation of Cranioplasty Flaps

Abstract Background: Cranioplasty, defined as the surgical repair of a defect in the cranium, has undergone many revolutions over time to improve patient prognosis. Cranioplasty offers cosmetic and protective benefits for patients with cranial defects. Aim of Study: A new method for the fixation of poly-methyl methacrylate (PMMA) cranioplasty flap is described, and the results of the technique were reported. Patients and Methods: Eighteen patients with cranial defects are included in the study. Patients were followed-up by clinical examination and periodic radiographic studies for a minimum of 6 months (range 6 to 12 months). Cosmetic appearance and solid fixation of the cranioplasty flap were evaluated. Results: Cosmetically good solid cranioplasty flaps oc-curred in all patients. There was no occurrence of infection or implant extrusion in any of the patients. Conclusion: This technique appears to be a simple, safe, economic and efficient method for PMMA cranioplasty flap fixation in reconstruction of significant cranial defects.

Cost-Effective Cranioplasty Utilizing 3D Printed Molds: A Canadian Single-Center Experience

ABSTRACT:Background:Cranioplasty is a commonly performed neurosurgical procedure used to repair defects of the cranial vault. For large defects, 3D printing allows for the creation of patient-specific synthetic cranioplasties. Although these implants provide excellent cosmetic results for patients, costs are quite high. This makes their routine use challenging in the current Canadian healthcare environment. The purpose of this study is to report our experience with a novel, cost-effective method for cranioplasty using desktop 3D printers to manufacture patient-specific molds to aid in the shaping of polymethyl methacrylate (PMMA) cranioplasty intraoperatively.Methods:A retrospective review of patients who underwent cranioplasty utilizing 3D printed custom molds was conducted at a single center between 2018 and 2020. Either a two-piece self-align or open-air mold was utilized. Material cost, as well as demographic, clinical, and radiologic data, was reviewed. A five-point ordinance scale was used to evaluate patient satisfaction with cosmesis.Results:Four patients had previous craniectomies with infected bone flaps, 2 patients had significant bony destruction from tumor invasion, and 1 patient had bone flap resorption. Three patients underwent an open-air mold technique with a Ti-mesh/PMMA-combined implant. The remaining 4 patients underwent two-piece mold with PMMA-only implant. All patients had ‘Good’ to ‘Excellent’ cosmetic outcome with one post-operative acute subdural hematoma and one post-operative infection. Two-piece mold resulted in improved cosmetic outcome and cost savings.Conclusions:3D printing can be used in a cost-effective manner to deliver good cranioplasty cosmesis. Wider adoption of this technique can result in significant healthcare cost savings without compromising patient outcome.

Designer Cranioplasty at Budget Prices: A Novel Use of 3D Printing Technology

Abstract Background Cranioplasty using synthetic materials for restoration of the exact shape of the skull has always remained a challenge until the development of 3D printing technology. However, the high-cost of available 3D printed implants limits their extensive use. Objectives To study the effectiveness of a low-cost, 3D-printed template for molding the polymethyl methacrylate (PMMA) (bone cement) in order to achieve exact contours of the skull specific to each patient. Materials and Methods 10 cranioplasties have been performed between July 2018 to December 2019 in a variety of craniotomy defects using bone cement flaps shaped using custom-made molds. The mold was 3D-printed and based on each patient’s CT images in digital imaging and communications in medicine (DICOM). Miniplates and screws were used to fix the flap. Postoperatively, clinical and radiological evaluation were done to assess patient satisfaction and accuracy of contour achieved. Results Patient satisfaction as well as accuracy of contouring, as seen on postoperative CT scans, were excellent. There were no notable complications on follow-up. Conclusion PMMA cranioplasty flap, contoured using a 3D-printed mold, is a very cost-effective alternative for restoration of skull contour for various craniotomy defects.Polymethyl methacrylate (PMMA) molded to form the exact shape of lost calvarium using 3D printed plastic templates is a smart and economical solution.

3D-Printer-Assisted Patient-Specific Polymethyl Methacrylate Cranioplasty: A Case Series of 16 Consecutive Patients

To develop a novel 3D-printer-assisted method to fabricate patient-specific implants for cranioplasty and to demonstrate its feasibility and its use in 16 consecutive cases. We report on 16 consecutive patients who have undergone cranioplasty surgery for an extensive skull defect after decompressive surgery and in which the bone flap was not available. We present the workflow for the implant production using a 3D-printer-assisted molding technique. Preoperative, intraoperative, and postoperative data were analyzed/evaluated. Eleven out of our 16 patients (68.7%) presented with extensive hemispheric bone defects. Indication for initial craniotomy were traumatic brain injury (4; 25%), acute subdural hematoma (4; 25%), ischemic stroke (3; 18.8%), tumor (3; 18.8%), and ruptured aneurysm (2; 12.5%). Median (range) operation time was 121 (89-206) minutes.Median (range) intraoperative blood loss was 300(100-3300) mL. The mean (range) follow-up period is 6 (0-21) months. Complications occurred in 7 out of our 16 patients (43.8%), in 6 (37.5%) of which a reoperation was required to evacuate an extra-axial hematoma (3; 50%), for shunting of an epidural fluid collection (1; 16.7%), or for skin flap necrosis (1; 16.7%). One patient (16.7%) developed a chronic asymptomatic subdural fluid collection that was stable over the follow-up period. Our workflow to intraoperatively produce patient-specific implants in a timely manner to cover cranial defects proved to be feasible. The results are cosmetically appealing, and postoperative CT scans show well-fitting implants. As implantable printable substrates are already available, we aim to advance and certify 3D-printed patient-specific implants in the near future.

Clinical evaluation of rapid 3D print-formed implants for surgical reconstruction of large cranial defects.

To clinically evaluate 3D print-formed implant process, using cranioplasty as a proof of concept, to examine its effectiveness and utility as a method of intraoperative implant fabrication. Twelve patients had a 3D print-formed template created for patient-specific implant manufacture. Of these patients, 10 received intraoperatively formed polymethylmethacrylate cranioplasty implants between 2013 and 2019. The 3D print-formed implant templates produced to manufacture these patient-specific implants were generated using patient computed tomography scans and 3D printed using fused deposition modelling technology. Cosmetic and functional results were determined by participating surgeons, in conjunction with a patient questionnaire. The functional results and stability of the implants were deemed to be favourable by participating surgeons. Three of the 10 patients completed a post-cranioplasty survey, all of whom judged their cosmetic results as good or excellent. At time of writing, the rate of surgical revision was zero and without clinically adverse outcomes. 3D print-formed implants are an effective method of patient-specific implant formation.

Safety, Feasibility, and Patient-Rated Outcome of Sonolucent Cranioplasty in Extracranial-Intracranial Bypass Surgery to Allow for Transcranioplasty Ultrasound Assessment

ObjectiveWe sought to analyze the safety and feasibility of elective sonolucent cranioplasty in the setting of extracranial-to-intracranial (EC-IC) bypass surgery to monitor bypass patency using ultrasound.MethodsPatients who underwent direct EC-IC bypass surgery agreed to sonolucent cranioplasty at the time of surgery and received a sonolucent polymethyl methacrylate (PMMA) implant. Besides monitoring clinical outcome, all patients received transcranioplasty ultrasound (TCUS) on postoperative day 1 and at last follow-up. In addition, bypass patency was confirmed using catheter angiogram and fit of implant using computed tomography. Patient-rated outcome was assessed through phone questionnaire.ResultsEC-IC bypass surgery with PMMA cranioplasty was successful in all 7 patients with patent bypasses on postoperative angiogram. Direct TCUS was feasible in all patients, and bypass patency was monitored. There were no complications such as postoperative hemorrhagic/ischemic complications related to the bypass procedure in this patient population, as well as no complications related to the PMMA implant. Postoperative computed tomography showed favorable cosmetic results of the PMMA implant in both the pterional area for superficial temporal artery−middle cerebral artery bypasses and parietooccipital area for occipital artery−middle cerebral artery bypasses as confirmed by high-rated overall patient satisfaction with favorable cosmetic, pain, and sensory patient-rated outcomes.ConclusionsIn this study we were able to show that this novel technique is safe, allows for patency assessment of the EC-IC bypass using bedside TCUS technique, and is cosmetically satisfying for patients.

In Reply to the Letter to the Editor Regarding “Polymethyl-Methacrylate Cranioplasty Is an Effective Ultrasound Window to Explore Intracranial Structures: Preliminary Experience and Future Perspectives”

In Reply to the Letter to the Editor Regarding “Polymethyl-Methacrylate Cranioplasty Is an Effective Ultrasound Window to Explore Intracranial Structures: Preliminary Experience and Future Perspectives”

Letter to the Editor Regarding “Polymethyl-Methacrylate Cranioplasty Is an Effective Ultrasound Window to Explore Intracranial Structures: Preliminary Experience and Future Perspectives”

Letter to the Editor Regarding “Polymethyl-Methacrylate Cranioplasty Is an Effective Ultrasound Window to Explore Intracranial Structures: Preliminary Experience and Future Perspectives”

Polymethyl Methacrylate Cranioplasty Is an Effective Ultrasound Window to Explore Intracranial Structures: Preliminary Experience and Future Perspectives

To evaluate the feasibility of transcranial sonography in patients harboring polymethylmethacrylate cranioplasties (PMMA-CP) and explore whether this material is a valid sonic window to explore intracerebral structures. In 6 patients, we performed transcranial sonography (TCS), using the PMMA-CP as sonic window. To test the reliability of ultrasound images, we collected several quantitative and qualitative measurements of intracranial structures and compared these sonographic images with standard computed tomography (CT) scan images. We found that PMMA-CP is a very good sonic window and allowed us to obtain very good quality echographic images of intracranial structures, as shown by the comparison of measurements with CT scan, which were very reliable. The main drawback was related to the shape (i.e., the curvature) of the cranial flap, which hindered the ultrasound probe from correctly adhering to the scalp. Although limited by the restricted number of cases, this preliminary experience represents the first available data about the serial use of TCS using PMMA-CP as window. These results open the path to the routine use of TCS to longitudinally control patients already harboring PMMA-CP. More, we here discuss its potential role in globally reducing the number of follow-up CT and magnetic resonance imaging scans required in different type of patients and pathologies.

Polymethylmethacrylate cranioplasty using low-cost customised 3D printed moulds for cranial defects – a single Centre experience: technical note

We report our experience with 3D customised cranioplasties for large cranial defects. They were made by casting bone cement in custom made moulds at the time of surgery. Between October 2015 and January 2018, 29 patients underwent the procedure; 25 underwent elective cranioplasties for large cranial defects and four were bone tumour resection and reconstruction cases. The majority of patients (96.5%) reported a satisfactory aesthetic outcome. No infections related to the surgical procedure were observed in the follow-up period. The method proved to be effective and affordable.

Cranioplasty with a low-cost customized polymethylmethacrylate implant using a desktop 3D printer.

Cranioplasty implants should be widely available, low in cost, and customized or easy to mold during surgery. Although autologous bone remains the first choice for repair, it cannot always be used due to infection, fragmentation, bone resorption, or other causes, which led to use of synthetic alternatives. The most frequently used allogenic material for cranial reconstructions with long-term results is polymethylmethacrylate (PMMA). Three-dimensional printing technology has allowed the production of increasingly popular customized, prefabricated implants. The authors describe their method and experience with a customized PMMA prosthesis using a precise and reliable low-cost implant that can be customized at any institution with open-source or low-cost software and desktop 3D printers. A review of 22 consecutive patients undergoing CT-based, low-cost, customized PMMA cranioplasty over a 1-year period at a university teaching hospital was performed. Preoperative data included patient sex and age; CT modeling parameters, including the surface area of the implant (defect); reason for craniectomy; date(s) of injury and/or resections; the complexity of the defect; and associated comorbidities. Postoperative data included morbiditiy and complications, such as implant exposure, infection, hematoma, seroma, implant failure, and seizures; the cost of the implant; and cosmetic outcome. Indications for the primary craniectomy were traumatic brain injury (16, 73%), tumor resection (3, 14%), infection (1, 4%), and vascular (2, 9%). The median interval between previous surgery and PMMA cranioplasty was 12 months. The operation time ranged from 90 to 150 minutes (mean 126 minutes). The average cranial defect measured 65.16 cm2 (range 29.31-131.06 cm2). During the recovery period, there was no sign of infection, implant rejection, or wound dehiscence, and none of the implants had to be removed over a follow-up ranging from 1 to 6 months. The aesthetic appearance of all patients was significantly improved, and the implant fit was excellent. The use of a customized PMMA was associated with excellent patient, family, and surgeon satisfaction at follow-up at a fraction of the cost associated with commercially available implants. This technique could be an attractive option to all patients undergoing cranioplasty.

Reconstruction of large cranial defects with poly-methyl-methacrylate (PMMA) using a rapid prototyping model and a new technique for intraoperative implant modeling

BackgroundReconstruction of large cranial defects after craniectomy can be accomplished by free-hand poly-methyl-methacrylate (PMMA) or industrially manufactured implants. The free-hand technique often does not achieve satisfactory cosmetic results but is inexpensive. In an attempt to combine the accuracy of specifically manufactured implants with low cost of PMMA. MethodsForty-six consecutive patients with large skull defects after trauma or infection were retrospectively analyzed. The defects were reconstructed using computer-aided design/computer-aided manufacturing (CAD/CAM) techniques. The computer file was imported into a rapid prototyping (RP) machine to produce an acrylonitrile-butadiene-styrene model (ABS) of the patient's bony head. The gas-sterilized model was used as a template for the intraoperative modeling of the PMMA cranioplasty. Thus, not the PMMA implant was generated by CAD/CAM technique but the model of the patients head to easily form a well-fitting implant. Cosmetic outcome was rated on a six-tiered scale by the patients after a minimum follow-up of three months. ResultsThe mean size of the defect was 74.36cm2. The implants fitted well in all patients. Seven patients had a postoperative complication and underwent reoperation. Mean follow-up period was 41 months (range 2–91 months). Results were excellent in 42, good in three and not satisfactory in one patient. Costs per implant were approximately 550 Euros. ConclusionPMMA implants fabricated in-house by direct molding using a bio-model of the patients bony head are easily produced, fit properly and are inexpensive compared to cranial implants fabricated with other RP or milling techniques.