Polymethylmethacrylate Implants Research Articles

Revision Cranioplasty with Three-dimensional Custom-made Titanium Implants in Patients with Failed Cranioplasty

Graft failure is a common complication of cranioplasty. Revision cranioplasty is required to overcome this complication. However, no previous studies have reported outcomes in revision cranioplasty with 3-dimensional (3D) custom-made titanium implants. We describe our experience with 3D titanium implants in patients with revision cranioplasty. We evaluated 43 consecutive patients between January 2011 and December 2019 who underwent revision cranioplasty using 3D custom-made titanium implants. The 3D image of the patient's cranium and the plan to close the cranium defect were created in a virtual environment using software programs. Demographic and radiologic features were compared based on the materials used in the initial cranioplasty. Previous material was autologous graft (AG) in 27 patients and polymethyl methacrylate (PMMA) in 16 patients. The mean time without revision cranioplasty is longer in patients with PMMA implants than in patients with AG. There was no statistically significant difference in the length of hospital stay between patients with PMMA implants and patients with AG. There were no postoperative adverse events such as infection, wound dehiscence, convulsions, or epidural hematoma in 38 patients during hospitalization. Wound dehiscence developed in 5 patients and surgical repair was required in one. Initial cranioplasty with PMMA provides a longer time period than the AG before the revision. However, both of them have similar outcomes based on length of hospital stay and cranial defect area. Custom-made 3D titanium implant is a good option for revision cranioplasty to prevent implant failure and reduce patients' cosmetic concerns.

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.

Letter to editor: Exploring complications following cranioplasty after decompressive hemicraniectomy: A retrospective bicenter assessment of autologous, PMMA and CAD implants.

This study presents a critical analysis of complications following cranioplasty (CP) after decompressive hemicraniectomy, focusing on autologous, polymethylmethacrylate (PMMA), and computer-aided design (CAD) implants. The analysis encompasses a retrospective bicenter assessment, evaluating factors influencing surgical outcomes and emphasizing the significance of material selection in minimizing postoperative complications. The study's comprehensive examination of complication rates associated with various implant materials contributes significantly to understanding CP outcomes. While polymethylmethacrylate (PMMA) and autologous bone flaps (ABFs) exhibited higher rates of surgical site infection (SSI) and explantation, a meta-analysis revealed a contrasting lower infection rate for polyether ether ketone (PEEK) implants. The study underscores the critical role of material selection in mitigating postoperative complications. Despite its strengths, the study's retrospective design, reliance on data from two centers, and limited sample size pose limitations. Future research should prioritize prospective, multicenter studies with standardized protocols to enhance diagnostic accuracy and treatment efficacy in CP procedures.

Exploring the Distinct Characteristic of Two Procedures for Sulcus Implementation following Posterior Capsular Rupture during Phacoemulsification: Single-piece Foldable IOLs and Polymethylmethacrylate IOLs

Introduction : Posterior capsular rupture (PCR) is one of the most feared complications of phacoemulsification. In? the?bag implantation of the lens becomes difficult if the PCR was large. Implantation of rigid polymethylmethacrylate (PMMA) or single?piece foldable IOL is implanted in the sulcus
 Case Illustration : After noting the PCR on both patients, single?piece foldable IOL of the same power was implanted in the ciliary sulcus. Same action was implemented to PMMA IOLs by enlarging the main port twice. Intracameral pilocarpine was injected and vitrectomy anterior was performed. The wound was closed with hydration on single-piece foldable IOL, meanwhile on PMMA IOLs, one hecting is required in the middle of mainport wound. The postoperative VA on day 1 from 0.12 on single-piece foldable IOLs and 0.25 on PMMA IOLs. Corneal edema, increased anterior chamber reaction was seen on single-piece foldable IOLs. Raised IOP was not found on both patients
 Discussion : Complications implantation single?piece foldable IOLs such as pigment dispersion syndrome, increased IOP. A surgical peripheral iridectomy can be created as a solution. Complication less likely occurred on the patient with longer axial length. The AL on this patient is AL 23.33 mm (single?piece foldable IOLs) and 24.08 mm (PMMA IOLs). The weakness of single piece foldable acrylic lenses are poor choice for ciliary sulcus placement and PMMA IOLs can induce astigmatism.
 Conclusion : Single-piece foldable IOLs are not designed for sulcus implantation. PMMA IOLs implantation can induce astigmatism.

Exploring complications following cranioplasty after decompressive hemicraniectomy: A retrospective bicenter assessment of autologous, PMMA and CAD implants

Cranioplasty (CP) after decompressive hemicraniectomy (DHC) is a common neurosurgical procedure with a high complication rate. The best material for the repair of large cranial defects is unclear. The aim of this study was to evaluate different implant materials regarding surgery related complications after CP. Type of materials include the autologous bone flap (ABF), polymethylmethacrylate (PMMA), calcium phosphate reinforced with titanium mesh (CaP-Ti), polyetheretherketone (PEEK) and hydroxyapatite (HA). A retrospective, descriptive, observational bicenter study was performed, medical data of all patients who underwent CP after DHC between January 1st, 2016 and December 31st, 2022 were analyzed. Follow-up was until December 31st, 2023. 139 consecutive patients with a median age of 54 years who received either PMMA (56/139; 40.3%), PEEK (35/139; 25.2%), CaP-Ti (21/139; 15.1%), ABF (25/139; 18.0%) or HA (2/139; 1.4%) cranial implant after DHC were included in the study. Median time from DHC to CP was 117 days and median follow-up period was 43 months. Surgical site infection was the most frequent surgery-related complication (13.7%; 19/139). PEEK implants were mostly affected (28.6%; 10/35), followed by ABF (20%; 5/25), CaP-Ti implants (9.5%; 2/21) and PMMA implants (1.7%, 1/56). Explantation was necessary for 9 PEEK implants (25.7%; 9/35), 6 ABFs (24.0%; 6/25), 3 CaP-Ti implants (14.3%; 3/21) and 4 PMMA implants (7.1%; 4/56). Besides infection, a postoperative hematoma was the most common cause. Median surgical time was 106 min, neither longer surgical time nor use of anticoagulation were significantly related to higher infection rates (p = 0.547; p = 0.152 respectively). Ventriculoperitoneal shunt implantation prior to CP was noted in 33.8% (47/139) and not significantly associated with surgical related complications. Perioperative lumbar drainage, due to bulging brain, inserted in 38 patients (27.3%; 38/139) before surgery was protective when it comes to explantation of the implant (p = 0.035). Based on our results, CP is still related to a relatively high number of infections and further complications. Implant material seems to have a high effect on postoperative infections, since surgical time, anticoagulation therapy and hydrocephalus did not show a statistically significant effect on postoperative complications in this study. PEEK implants and ABFs seem to possess higher risk of postoperative infection. More biocompatible implants such as CaP-Ti might be beneficial. Further, prospective studies are necessary to answer this question.

Demonstration of Cosmetic Improvement After Cranioplasty Using a Personalized 3D-Printed Mold for Creating Polymethylmethacrylate Implants With a Simplified Process

Although personalized polymethylmethacrylate (PMMA) implant production molds for cranioplasty are costly and time-consuming, they allow for better-quality implants. The researchers quantitatively tested the contribution of simplified, low-cost techniques to cosmetic improvement. PMMA prosthesis was placed in a 25-year-old male patient due to osteolysis in the bone flap removed after decompression surgery. A single-sided mold was three-dimensional (3D) printed before the surgery, and the prosthesis was produced during the surgery. In addition, the change in cranial asymmetry was evaluated using a 3D surface scanner after surgery. The mold took half an hour to design and 5hours to print. The mold cost about 2 dollars. The root means square (RMS) value measured to determine cranial asymmetry decreased from 5.4mm to 2.8mm postoperatively. The patient stated that he was pretty satisfied with the cosmetic result. Simple design techniques developed can offer low-cost, fast-design alternative solutions with satisfactory cosmetic results for low-income countries and patients.

Pmma body injection and hypercalcemia correlation: a cross-sectional observational study on the comprehensive analysis of variables

Introduction: Hypercalcemia related to aesthetic intramuscular implants exclusively made of PMMA (polymethylmethacrylate) is a very rare condition. Late complications of these implants are related to poorly understood inflammatory triggers, which may reactivate stabilized implants, increase calcitriol production, and lead to hypercalcemia. Methods: Records of patients seen between 2022 and 2023 with a PMMA microsphere body implant and a subsequent diagnosis of hypercalcemia were searched. Medical history, medication use, data on PMMA implantation, and laboratory tests related to calcium metabolism were described and subjected to variable correlation analysis. The instituted treatments were described. Results: A total of 17 female patients with exclusive body PMMA implants confirmed by ultrasonography or MRI (Magnetic Resonance Image) developed hypercalcemia between 2017 and 2022. Prior renal disease, COVID-19 infection, vitamin D use, and anabolic steroid use correlated with laboratory changes in hypercalcemia. Larger PMMA implant volumes led to parathyroid hormone suppression. Conclusion: Patients with PMMA body implants may rarely present with hypercalcemia when variables such as renal disease before implantation, high doses of vitamin D or anabolic steroids are present. Based on the data presented and the available scientific literature, recommendations for patient investigation, implant volume limit, and patient follow-up after the procedure were made.

Custom-made 3D printing-based cranioplasty using a silicone mould and PMMA

All types of cranioplasty techniques restore the morphology of the skull and affect patient aesthetics. Safe and easy techniques are required to enhance patients’ recovery and the rehabilitation process. We propose a new method of cranioplasty. The 3-dimensional (3D) reconstruction of a thin-layer computed tomography (CT) scan of the skull was used to reflect the intact side onto the defect and subtract the overlapping points from one another. In this way, a 3D model of the planned implant can be built in the required shape and size. The precise fit of the implant can be checked by printing the defective part of the skull in case it can be modified. A sterilisable silicone mould based on the finalized model was created afterwards. Polymethyl methacrylate implants were prepared directly in an aseptic environment in the operating room during surgery. Between 2005 and 2020, we performed 54 cranioplasties on 52 patients whose craniotomies were performed previously for indications of traumatic brain injury, stroke or tumour surgeries. No technical problems were noted during the operations. In 2 cases, septic complications that occurred were not connected to the technique itself, and the implants were removed and later replaced. Our proposed technique based on 3D-printed individual silicone moulds is a reliable, safe, easily reproducible and low-cost method to repair different skull defects.

Tissue response to a novel bone adhesive implanted subcutaneously in rats: A histological and gene expression analysis

AbstractMedian sternotomy provides access to the heart and surrounding valves for cardiothoracic surgery. However, complications arise such as micro‐motion and separation between the two sternal halves. To prevent these complications, the use of a bone adhesive has been proposed to augment the mechanical union of the two sternal halves when combined with wire cerclage. Our group has developed a bone adhesive for sternal fixation, utilizing a glass polyalkenoate cement (GPC) based on a zinc silicate ionomeric glass (mole fraction: SiO2:0.48, ZnO:0.36, CaO:0.12, SrO:0.04). Here we present the first soft‐tissue biological safety assessment of this novel Sr/Zn‐GPC, where we implanted the material subcutaneously in rats for 6 and 12 weeks. Polymethyl‐methacrylate (PMMA) bone cement was used as a baseline control with respect to inflammation and biocompatibility. Histological assessment revealed no adverse tissue reaction nor ectopic bone formation in response to the novel material. Additionally, relative expression of pro‐inflammatory and osteogenic genes (Col1a1, SOX9, Runx2, IL‐1, IL‐6, and TNF‐α) was assessed in the tissue surrounding implants and revealed no significant differences in expression between the Sr/Zn‐GPC and PMMA implants.

Are large diameter cannulas safe in nonsurgical rhinoplasty?

Are large diameter cannulas safe in nonsurgical rhinoplasty?

Фемтолазерная интрастромальная имплантация роговичных сегментов с использованием цифрового разметочного устройства в хирургическом лечении кератоконуса

Purpose. To develop a technology for topographically oriented positioning of intrastromal segments during femtolaser intrastromal keratoplasty (ISKP) in patients with keratoconus using a digital marking device and to evaluate its clinical efficacy. Material and methods. The study included 102 patients (102 eyes) with stage II keratoconus according to the Amsler – Krumeich classification. According to the type of surgery performed, the patients were divided into groups: the main group (53 patients (53 eyes) – femtolaser ISKP with implantation of polymethyl methacrylate (PMMA) segments was performed using a digital marking device and taking into account the cyclotorsion angle; control group (49 patients (49 eyes)) – femtolaser ISKP with implantation of PMMA segments was performed using the standard method (marking the geometric center of the cornea using the Purkenier – Sanson reflex without taking into account cyclotorsion). Results. The indices of the «success» index, the calculated vector of astigmatism close to the actual postoperative one and a smaller value of the vector of the difference in the axis of astigmatism, confirmed the higher accuracy of ISKP with the use of a digital marker compared to the standard one. The mean values of visual acuity and best corrected visual acuity 12 months after surgery in the main group were 0.58 ± 0.05 and 0.80 ± 0.04, respectively, and in the control group they were at the level of 0.49 ± 0.06 and 0.68 ± 0.05 respectively. After the surgery, there was a statistically significant decrease in the mean values of astigmatism: the main group – after 3 months to -1.8 ± 0.15 diopters (p <0.05), after 6 months – by another 1.7 ± 0.20 diopters (p <0.05); the control group – after 3 months to -2.43 ± 0.17 diopters (p <0.05), after 6 months – by another 2.42 ± 0.17 diopters. Conclusion. The proposed optimized ISKP technique with the use of a digital marking device provides precise positioning of segments during the surgical treatment of keratoconus and allows to obtain higher acuity of vision and best corrected visual acuity, as well as to correct corneal astigmatism more efficiently than using standard technique. Key words: surgical treatment of keratoconus, femtolaser intrastromal implantation of corneal segments, digital marking device.

Intracorneal ring segments for KC and iatrogenic keratectasia

AbstractICRS are polymethylmethacrylate (PMMA) implants developed to be inserted in the corneal stroma aiming to remodel the ectatic corneal curvature. In 2000, ICRS have been introduced for the implantation in KC treatment. Since then, several authors have demonstrated the efficacy of this surgical procedure for improving the refractive and topographic results of KC patients. Moreover, the method has been extended to a larger spectrum of corneal ectasia, such as pellucid marginal degeneration (PMD) and iatrogenic ectasia after laser in situ keratomileusis (LASIK). Our aim was to evaluate the functional results, i.e. how uncorrected and corrected distance visual acuity can be improved by implantation of ICRS. Progression of ectasia seems to be retarded. However, consistent follow‐up visits at close intervals are necessary to identify complications at an early stage. The complications after ICRS implantation are rare due to strict patient selection and modern surgical techniques.

Analysis of PMMA versus CaP titanium-enhanced implants for cranioplasty after decompressive craniectomy: a retrospective observational cohort study

Numerous materials of implants used for cranioplasty after decompressive craniectomy (DC) have been investigated to meet certain demanded key features, such as stability, applicability, and biocompatibility. We aimed to evaluate the feasibility and safety of biocompatible calcium-phosphate (CaP) implants for cranioplasty compared to polymethylmethacrylate (PMMA) implants. In this retrospective observational cohort study, the medical records of all patients who underwent cranioplasty between January 1st, 2015, and January 1st, 2022, were reviewed. Demographic, clinical, and diagnostic data were collected. Eighty-two consecutive patients with a mean age of 52 years (range 22–72 years) who received either a PMMA (43/82; 52.4%) or CaP (39/82; 47.6%) cranial implant after DC were included in the study. Indications for DC were equally distributed in both groups. Time from DC to cranioplasty was 143.8 ± 17.5 days (PMMA) versus 98.5 ± 10.4 days (CaP). The mean follow-up period was 34.9 ± 27.1 months. Postoperative complications occurred in 13 patients with PMMA and 6 in those with CaP implants (13/43 [30.2%] vs. 6/39 [15.4%]; p = 0.115). Revision surgery with implant removal was necessary for 9 PMMA patients and in 1 with a CaP implant (9/43 [20.9%] vs. 1/39 [2.6%]; p = 0.0336); 6 PMMA implants were removed due to surgical site infection (SSI) (PMMA 6/43 [14%] vs. CaP 0/39 [0%]; p = 0.012). In this study, a biocompatible CaP implant seems to be superior to a PMMA implant in terms of SSI and postoperative complications. The absence of SSI supports the idea of the biocompatible implant material with its ability for osseointegration.

Clinical commentary about foreign body complications over 20years after polymethyl-methacrylate face implants and control of late sequelae with Polynucleotides Highly Purified Technology (PN-HPT® ).

Mainly in the past, foreign body complications, including granuloma, were pretty frequent after semi-permanent polymethyl-methacrylate (PMMA) implants. The authors describe a twenty-year history of recurring post-PMMA complications interspersed by long uneventful years, with acute edematous side effects evolving into unpleasant skin dystrophia with persistent cutis laxa. The case report also discusses a simple clinical algorithm to discriminate among foreign body complications with particular attention to granulomas. The authors conclude by discussing the benefits of the anti-dystrophic treatment with natural-origin remodeling PN-HPT® (Polynucleotides Highly Purified Technology).

Biomechanical Evaluation of Patient-Specific Polymethylmethacrylate Cranial Implants for Virtual Surgical Planning: An In-Vitro Study.

Cranioplasty with freehand-molded polymethylmethacrylate implants is based on decades of experience and is still frequently used in clinical practice. However, data confirming the fracture toughness and standard biomechanical tests are rare. This study aimed to determine the amount of force that could be applied to virtually planned, template-molded, patient-specific implants (n = 10) with an implant thickness of 3 mm, used in the treatment of a temporoparietal skull defect (91.87 cm2), until the implant cracks and finally breaks. Furthermore, the influence of the weight and porosity of the implant on its force resistance was investigated. The primary outcome showed that a high force was required to break the implant (mean and standard deviation 1484.6 ± 167.7 N), and this was very strongly correlated with implant weight (Pearson’s correlation coefficient 0.97; p < 0.001). Secondary outcomes were force application at the implant’s first, second, and third crack. Only a moderate correlation could be found between fracture force and the volume of porosities (Pearson’s correlation coefficient 0.59; p = 0.073). The present study demonstrates that an implant thickness of 3 mm for a temporoparietal skull defect can withstand sufficient force to protect the brain. Greater implant weight and, thus, higher material content increases thickness, resulting in more resistance. Porosities that occur during the described workflow do not seem to reduce resistance. Therefore, precise knowledge of the fracture force of polymethylmethacrylate cranial implants provides insight into brain injury prevention and serves as a reference for the virtual design process.

Features of modeling a polymer implant for closing a defect after decompressive craniotomy

Individual polymer implants are widespread for bone reconstruction after decompressive craniectomy. Despite the availability of customized titanium products, various specialists and hospitals prefer polymer implants. To compare the methods of modeling and manufacturing the polymethylmethacrylate implants and identify the features affecting the quality of reconstruction. We analyzed 14 patients with extensive skull defects after installation of polymethyl methacrylate implants. Software used for modeling of individual implants by different specialists was compared. Satisfactory reconstruction result was obtained in all cases. There were no infectious complications. The authors outlined certain important aspects for modeling of individual polymer products: local use of anatomical thickness of the implant, leaving safe spaces, prevention of temporal retraction, template-based resection before reconstruction. To date, skull defect closure with polymeric materials remains relevant, and even has certain advantages over customized titanium products.

Cold-Injection Molded Gentamicin-Impregnated Polymethyl Methacrylate Implants for Cranioplasty.

Cranioplasty can be carried out using either fresh, frozen autologous bone or synthetic substitutes. Ordering artificial 3 dimensional (3D) implants is challenging and time consuming depending on geographical location. In this article, we share our experience using a streamlined process of producing 3D computer-assisted design (CAD) implants using commercially available 3D printers and silicone molds that can be easily replicated with consistent results and are associated with good outcomes. To develop patient-specific implants for patients with cranial defects that are accurate, consistent, low cost, and easy to replicate while reducing operator-dependent factors. We present data from 15 patients who underwent cranioplasty with 3D CAD-designed gentamicin-impregnated bone cement implants that were molded using the cold injection technique. The technique was consistent in result production, required little postdemolding manipulation, and showed no dimensional variation in design. Postoperative computed tomography scans showed excellent implant fit, and patients had a low complication rate. We have demonstrated a technique of mold preparation that is efficient and that produces a reliable result. Polymethyl methacrylate implants molded using this technique showed better reproducibility, higher accuracy, and precision than other types of implants and required minimal postdemolding clean-up.

Cranioplasty with three-dimensional customised mould for polymethylmethacrylate implant: a series of 16 consecutive patients with cost-effectiveness consideration

BackgroundDifferent methods of cranioplasty for the reconstruction of bony skull defects exist. In the absence of the autologous bone flap, a customised manufactured implant may be the optimal choice, but this implant has several limitations regarding its technical standardisation and better cost-effectiveness.MethodsThis study presents a series of 16 consecutive patients who had undergone cranioplasty with customised three-dimensional (3D) template moulds for polymethylmethacrylate (PMMA) implants manufactured after 3D modelling on a specific workstation. The virtual images were transformed into a two-piece physical model using a 3D printer for the biomaterials. PMMA implant was produced intraoperatively with the custom mould. Cosmetic results were analysed by comparing pre- and postoperative 3D computed tomography (CT) images and asking if the patient was satisfied with the result.ResultsThe average total time for planning and production of customised mould was 10 days. The 16 patients were satisfied with the result, and CT images presented harmonious symmetry when comparing pre- and postoperative scans. Cases of postoperative infection, bleeding, or reoperation in this series were not observed.ConclusionCranioplasty with high-technology customised 3D moulds for PMMA implants can allow for an aesthetic reconstruction with a fast and cost-effective manufacturing process and possibly with low complication rates.

Graphene-Doped Poly (Methyl-Methacrylate) (Pmma) Implants: A Micro-CT and Histomorphometrical Study in Rabbits.

Background—the graphene-doping procedure represents a useful procedure to improve the mechanical, physical and biological response of several Polymethyl methacrylate (PMMA)-derived polymers and biomaterials for dental applications. The aim of this study was to evaluate osseointegration of Graphene doped Poly(methyl methacrylate) (GD-PMMA) compared with PMMA as potential materials for dental implant devices. Methods—eighteen adult New Zealand white male rabbits with a mean weight of approx. 3000 g were used in this research. A total of eighteen implants of 3.5 mm diameter and 11 mm length in GD-PMMA and eighteen implants in PMMA were used. The implants were placed into the articular femoral knee joint. The animals were sacrificed after 15, 30 and 60 days and the specimens were evaluated by µCT and histomorphometry. Results—microscopically, all 36 implants, 18 in PMMA and 18 in DG-PMMA were well-integrated into the bone. The implants were in contact with cortical bone along the upper threads, while the lower threads were in contact with either newly formed bone or with marrow spaces. The histomorphometry and µCT evaluation showed that the GP-PMMA and PMMA implants were well osseointegrated and the bone was in direct contact with large portions of the implant surfaces, including the space in the medullary canal. Conclusions—in conclusion, the results suggest that GD-PMMA titanium surfaces enhance osseointegration in rabbit femurs. This encourages further research to obtain GD-PMMA with a greater radiopacity. Also, further in vitro and vivo animal studies are necessary to evaluate a potential clinical usage for dental implant applications.

Evaluation of implant properties, safety profile and clinical efficacy of patient-specific acrylic prosthesis in cranioplasty using 3D binderjet printed cranium model: A pilot study

There exists a significant demand to develop patient-specific prosthesis in reconstruction of cranial vaults after decompressive craniectomy. we report here, the outcomes of an unicentric pilot study on acrylic cranial prosthesis fabricated using a 3D printed cranium model with its clinically relevant mechanical properties. MethodsThe semi-crystalline polymethyl methacrylate (PMMA) implants, shaped to the cranial defects of 3D printed cranium model, were implanted in 10 patients (mean age, 40.8 ± 14.8 years). A binderjet 3D printer was used to create patient-specific mould and PMMA was casted to fabricate prosthesis which was analyzed for microstructure and properties. Patients were followed up for allergy, infection and cosmesis for a period of 6 months. ResultsAs-cast PMMA flap exhibited hardness of 15.8 ± 0.24Hv, tensile strength of 30.7 ± 3.9 MPa and elastic modulus of 1.5 ± 0.1 GPa. 3D microstructure of the semi-crystalline acrylic implant revealed 2.5–15 µm spherical isolated pores. The mean area of the calvarial defect in craniectomy patients was 94.7 ± 17.4 cm2. We achieved a cranial index of symmetry (CIS -%) of 94.5 ± 3.9, while the average post-operative Glasgow outcome scale (GOS) score recorded was 4.2 ± 0.9. Conclusions3D printing based patient-specific design and fabrication of acrylic cranioplasty implant is safe and achieves acceptable cosmetic and clinical outcomes in patients with decompressive craniectomy. Our study ensured clinically acceptable structural and mechanical properties of implanted PMMA, suggesting that a low cost 3D printer based PMMA flap is an affordable option for cranioplasty in resource constrained settings.