Porous High-density Polyethylene Research Articles

CURRENT APPROACHES TO MANAGING MICROTIA

Microtia, a developmental anomaly of the external ear resulting in a deformed auricle, affects 1 to 5 individuals per 10,000. Literature suggests a male predominance, with nearly 2.5 times more male patients affected than females. Additionally, there is a notable right-sided predilection, leading to pronounced asymmetry, observed in approximately 83% of cases. Surgical reconstruction is the primary treatment for microtia, albeit a technically demanding procedure with challenges in achieving optimal aesthetic outcomes. Reconstruction typically involves autologous costal cartilage, known for its effectiveness but requiring advanced surgical skills. Complications, including pneumothorax, postoperative pain, chest wall deformity, and pathological scarring, are common with this approach. In recent years, surgeons have increasingly adopted modern techniques utilizing porous high-density polyethylene implants for reconstruction. This approach is gaining popularity due to the challenges associated with achieving satisfactory cosmetic results using autologous costal cartilage reconstruction. Based on the bibliosemantic and analytical methods employed to analyze the literature, we posit that this topic necessitates further investigation and a multidisciplinary approach. The involvement of otolaryngologists and maxillofacial surgeons is imperative for the comprehensive treatment of this pathology.

High-Density Porous Polyethylene Implant Cranioplasty: A Systematic Review of Outcomes.

Porous polyethylene has been widely used in craniofacial reconstruction due to its biomechanical properties and ease of handling. The objective of this study was to perform a systematic review of the literature to summarize outcomes utilizing high-density porous polyethylene (HDPP) implants in cranioplasty. A literature search of PubMed, Cochrane Library, and Scopus databases was conducted to identify original studies with HDPP cranioplasty from inception to March 2023. Non-English articles, commentaries, absent indications or outcomes, and nonclinical studies were excluded. Data on patient demographics, indications, defect size and location, outcomes, and patient satisfaction were extracted. Summary statistics were calculated using weighted averages based on the available reported data. A total of 1089 patients involving 1104 cranioplasty procedures with HDPP were identified. Patients' mean age was 44.0 years (range 2 to 83y). The mean follow-up duration was 32.0 months (range 2wk to 8y). Two studies comprising 17 patients (1.6%) included only pediatric patients. Alloplastic cranioplasty was required after treatment of cerebrovascular diseases (50.9%), tumor excision (32.0%), trauma (11.4%), trigeminal neuralgia/epilepsy (3.4%), and others such as abscesses/cysts (1.4%). The size of the defect ranged from 3 to 340cm2. An overall postoperative complication rate of 2.3% was identified, especially in patients who had previously undergone surgery at the same site. When data were available, contour improvement and high patient satisfaction were reported in 98.8% and 98.3% of the patients. HDPP implants exhibit favorable outcomes for reconstruction of skull defects. Higher complication rates may be anticipated in secondary cranioplasty cases.

HIGH DENSITY POROUS POLYETHYLENE FACIAL IMPLANTS AS AN ALTERNATIVE MATERIAL IN MAXILLOFACIAL RECONSTRUCTION - AN INTEGRATIVE REVIEW

Porous high-density polyethylene (PPAD) is a material used for around 30 years in superficial reconstruction surgeries, a fact demonstrated in several cases in clinical practice. However, some questions arise regarding its safety, frequency and differences with other materials. Therefore, an integrative review of the literature was carried out using 9 articles found and selected in the Pubmed and Medline databases with the aim of analyzing their properties as a material of choice in maxillofacial reconstruction surgeries, clarifying the principles of biocompatibility, durability and safety., as well as its complications and failure rates. In terms of safety, PPAD was a reported material, with a low risk of complications, with infection being the main one. However, the authors cite some conditions that influence infection rates. Furthermore, it is characterized to present several advantages in relation to other materials used as metallic implants, such as PMMA, silicone, ePTFE, PEEK, and metallic implants. Therefore, polyethylene provides a permanent result, with good facial contouring, cost-benefit and long-term safety for the patient.

HIGH DENSITY POROUS POLYETHYLENE FACIAL IMPLANTS (PPAD) IN OROFACIAL HARMONIZATION

This work constitutes a literature review that explores the significance of Orofacial Harmonization Procedures (OHP) utilizing High-Density Porous Polyethylene Facial Implants (HDPE) to enhance facial aesthetics, contouring, rejuvenation, and volume augmentation. The paper addresses both theoretical and practical aspects of these procedures, providing insights into surgical technique, anatomy of treated areas, pre-operative assessment, anesthesia, pharmacology, medication, post-operative care, and potential complications. The review underscores the role of facial aesthetics in forming initial impressions and how aesthetic dental procedures within OHP are gaining popularity to achieve such harmony. It also emphasizes the integration of positive psychology in understanding aesthetic procedures, considering the positive psychological impacts on patients’ self-esteem and confidence. The work comprehensively discusses the use of HDPE as an alloplastic material for facial implants, elucidating its attributes such as the porous structure enabling implant vascularization and incorporation, along with its superiority over other materials in terms of inflammation and durability. Practical aspects of performing these procedures are addressed, encompassing commonly treated areas (chin, jaw, cheek), incision and suture techniques, anesthesia selection, antibiotic administration, and pre- and post-operative care. Furthermore, potential complications are presented, including improper patient selection, edema, infection, migration, extrusion, and others. The study highlights the significance of proper patient selection, surgical technique, and post-operative care for successful HDPE facial implant procedures. The review concludes that this technique can yield significant benefits in enhancing patients’ self-esteem and appearance, yet underscores the importance of adequate professional training and rigorous monitoring to prevent complications.

Application of a Single T-Shaped Porous High-Density Polyethylene in Oriental Nasal Tip-Plasty.

Porous high-density polyethylene (pHDPE) is an alternative material for septal extension grafts. This study investigated the clinical application of a single T-shaped pHDPE graft combined with auricular cartilage in oriental nasal tip-plasty. A retrospective analysis was conducted of 66 patients who underwent septal extension graft with a T-shaped pHDPE and auricular cartilage graft from December 2018 to November 2021. All patients were female from 19 to 51 years old (average: 28.9 years). Patients were followed up for 5 to 40 months with an average of 23.8 months. The postoperative nasal length (39.8±3.7mm) was significantly improved (35.6±5.7mm preoperatively, P <0.0001) with the tip projection increasing from 23.9±2.3mm preoperatively to 25.3±2.4mm postoperatively ( P =0.0005). There was a significant difference in the nasolabial angle (96.8±14.1 degrees preoperatively versus 101.8±7.2 degrees postoperatively, P =0.0105) but no significant change in the nasofrontal angle (143.3±9.5 degrees preoperatively versus 143.7±5.5 degrees postoperatively, P =0.7546), with an improved tip projection achieved in 93.9% of patients. One patient had an abscess in the nasal septum and a tip graft was performed using auricular cartilage in another patient because of an insufficient postoperative tip projection. There was a slight tip deviation in 2 patients, 1 case of a deviated nasal tip was corrected with a pHDPE sheet graft, while the other was left intact. Two patients had excess cartilaginous graft protruding to the nasal cavity that did not affect nasal ventilation and the shape of the nasal tip was relatively good, so the prominent cartilaginous graft was not addressed. In conclusion, this technique not only improved the bulbous nasal tip, lengthened the short nose, and increase the tip projection, but also prevented absorption of the existing septal cartilage and reduced infection or extrusion of the pHDPE.

Complications Following Alloplastic Chin Augmentation: A Systematic Review of Implant Materials and Surgical Techniques.

Alloplastic implantation has become a popular method of chin augmentation. Historically, silicone was the most commonly used implant, but porous materials have grown in favor due to improved fibrovascularization and stability. Nevertheless, it is unclear which implant type has the most favorable complication profile. This systematic review aims to compare the complications of published chin implants and surgical approaches to provide data-driven recommendations for optimizing chin augmentation outcomes. The PubMed® database was queried on March 14, 2021. We selected studies reporting data on alloplastic chin augmentation excluding additional procedures such as osseous genioplasty, fat grafting, autologous grafting, and fillers. The following complications were extracted from each article: malposition, infection, extrusion, revision, removal, paresthesias, and asymmetry. Among the 39 articles analyzed, the year of publication ranged from 1982 to 2020; additionally, 31 were retrospective case series, 5 were retrospective cohort or comparative studies, 2 were case reports, and 1 was a prospective case series. More than 3104 patients were included. Among the 11 implants reported, the 3 implants with the highest number of publications were silicone, high-density porous polyethylene (HDPE), and expanded polytetrafluoroethylene (ePTFE). Silicone demonstrated the lowest rates of paresthesias (0.4%) compared to HDPE (20.1%, P < 0.01) and ePTFE (3.2%, P < 0.05). In contrast, there were no statistically significant differences in rates of implant malposition, infection, extrusion, revision, removal, or asymmetry when stratified by implant type. Various surgical approaches were also documented. Compared with subperiosteal implant placement, the dual-plane technique demonstrated higher rates of implant malposition (2.8% vs 0.5%, P < 0.04), revision (4.7% vs 1.0%, P < 0.001), and removal (4.7% vs 1.1%, P < 0.01), but a lower incidence of paresthesias (1.9% vs. 10.8%, P < 0.01). Compared with extraoral incisions, intraoral incisions resulted in higher rates of implant removal (1.5% vs 0.5%, P < 0.05) but lower rates of asymmetry (0.7% vs 7.5%, P < 0.01). Silicone, HDPE, and ePTFE had low overall complication rates, demonstrating an acceptable safety profile regardless of implant selection. Surgical approach was found to significantly influence complications. Additional comparative studies on surgical approach while controlling for implant type would be beneficial for optimizing alloplastic chin augmentation practices.

Repair of exposure and fracture of the porous high-density polyethylene framework after ear reconstruction

ObjectiveTo assess the repair method of exposure or fracture of the porous high-density polyethylene ear framework after total auricle reconstruction.Study designA prospective case study.MethodsFrom April 2018 to October 2021, 11 patients with framework exposure or fracture after total auricle reconstruction were admitted to the hospital for repair. In these 11 patients, the repair was performed using (1) a temporal muscle flap combined with free skin graft in 5 patients, (2) a mastoid fascia flap combined with free skin graft in 2 patients, (3) a simple local skin flap in 1 patient, (4) combination of a temporalis muscle flap and a mastoid fascia flap together with free skin graft in 2 patients, and (5) a Su-Por helix material combined with a temporal muscle flap and free skin graft in 1 patient.ResultsAfter follow-up for 3–36 months, except for one patient in whom local exposure again occurred at the same site, the framework was in a good shape in the other patients, and all the skin graft survived.ConclusionThe defect of the upper part of the auricle can be repaired using a temporal muscle flap combined with temporal muscle fascia and skin graft. The defect of the middle and lower part of the auricle can be repaired using a mastoid fascia flap combined with skin graft. For framework fracture, the damaged site can be first strengthened with another ear material and then combined with the adjacent fascia flap and free skin graft.

Commentary on “Complications Associated with Use of Porous High-Density Polyethylene in Rhinoplasty” by Davis et al

Commentary on “Complications Associated with Use of Porous High-Density Polyethylene in Rhinoplasty” by Davis et al

Complications Associated with Use of Porous High-Density Polyethylene in Rhinoplasty.

Background: Porous high-density polyethylene (pHDPE) has successfully been used as an alternative to cartilage for grafting in rhinoplasty; however, concerns exist surrounding its potential for infection and/or extrusion. Objectives: To analyze the relationship between complication rates associated with pHDPE in rhinoplasty and graft location relative to shear force applied by external manipulation. Methods: Retrospective review of 116 patients undergoing pHDPE rhinoplasty for 10 years. Results: Minor postoperative complications occurred in 3.4% of patients, each resolving with conservative management. Major complications including infection or extrusion occurred in 5.2% of all patients, at an average of 36.9 months postoperatively. All major complications occurred in patients with grafts extending into the caudal nose, and two-thirds ultimately necessitated surgical intervention. Conclusions: Cephalically contained pHDPE grafts are less prone to failure than those extending into the caudal nose. Long-term follow-up is recommended for all patients based on the risk for delayed complications.

Revision Operation of the Unsatisfactory Microtia Reconstruction With Autologous Costal Cartilage.

Revision operation of the unsatisfactory microtia reconstruction is 1 of the most difficult revision operations in plastic surgery. This study discussed the cases about revision operation of the unsatisfactory or failed ear reconstruction using autologous costal cartilage and residual. A prospectively maintained database of all consecutive patients who underwent secondary total ear reconstruction from 2013 to 2020 was reviewed. Demographic data and outcomes were assessed. Thirty-six patients with microtia met the inclusion criteria. The age of the patients who underwent secondary reconstruction ranged 6 to 56 years. The follow-up duration was from 1 to 8 years. Primary reconstruction using costal cartilage was performed in 34 cases, and Medpor (porous high-density polyethylene) were used in 2 cases. All 36 cases were treated with costal cartilage as the revision. One-stage revision was performed in 27 cases, including scaffold covered by superficial temporal fascia flap in 9 cases, retroauricular fascia flap in 12 cases and superficial temporal plus retroauricular fascia flap in 5 cases. Nine cases were renovated with expanders by stages, of which 8 cases were covered by retroauricular fascia and 1 case was covered by expanded skin flap. Complications occurred in 2 cases, and 1 patient was not satisfied with the partial scaffold repair. The effect of revision operation of ear reconstruction with costal cartilage is satisfactory, and different methods of ear reconstruction are indicated in different operation conditions, and the revision surgery requires adequate preoperative evaluation.Level of Evidence: Level IV, therapeutic study.

Novel method for high-density porous polyethylene ear reconstruction stent remodeling to achieve high satisfactory outcomes.

We aimed to explore a novel method for ear reconstruction stent remodeling to achieve high patient satisfactory outcomes. This study is a retrospective review of patients with congenital or acquired ear defects who were prepared for one-stage ear reconstruction with high-density porous polyethylene stent between May 2020 and May 2021. A standardized data collection template was used to collect related variables. In this study, the detailed reconstruction surgery process is carefully described, and the postoperative healing process of the ear reconstruction was closely observed. A total of 26 patients for one-stage ear reconstruction with high-density porous polyethylene stent or autogenous costal cartilage scaffolds were admitted to the department of plastic surgery in our hospital between May 2020 and May 2021. All patients were followed until their ear flaps were alive and details of the ear shape were revealed. The patients with new remolding method were no severe complications and only a patient had stent exposure, and were highly satisfied with both appearance and function. The application of novel remodeling method is a promising way for ear reconstruction stent shaping with little postoperative complication and excellent postoperative patient satisfaction.

Patient specific implants in orbital reconstruction: A pilot study

PurposeSuccessful repair of the orbital skeleton restores function and cosmesis by normalizing globe position and allowing full motility of the extraocular muscles. Routine repairs are successful with standard implants. However, defects that are irregular or cause volume deficiency can be challenging to repair. The development of patient specific implants (PSI) offers an additional tool in complex cases. Herein, we report our experience using PSI for orbital reconstruction. MethodsAn IRB-approved review was conducted of consecutive patients who received PSI from 8/2016–9/2018. Demographic and examination findings were recorded. PSI was designed using high-density porous polyethylene or polyetheretherketone (PEEK) and implanted for repair. The postoperative course was reviewed for outcomes and complications. ResultsEight patients were identified. Two had silent sinus syndrome, 3 were complex facial fracture revisions, and 3 were post-oncologic reconstruction. Seven received porous polyethylene implants, and 1 had a PEEK implant. Mean follow up time was 10.2 months (3.3–28.3). All had an improved functional and aesthetic result. Diplopia and enophthalmos completely resolved in 60% of fracture and silent sinus patients. All fracture and silent sinus patients were orthotropic without diplopia in primary gaze at last follow up. Tumor patients had improvement in symmetry and functionality. There were no complications. Conclusion and importanceComplex orbital skeleton derangements can be difficult to repair and standard implants may incompletely resolve the anatomic problem. In challenging cases, PSI may better achieve an aesthetically and anatomically successful outcome and improve functionality.

Systematic Review of Medpor Versus Autologous Ear Reconstruction.

Ear reconstruction is 1 of the most technically challenging sub-specialties of craniofacial and reconstructive plastic surgery. The reconstructive ear must not only fulfil the requirement of being aesthetically pleasing but must also have good vascularity with a low complication rate. Several ear reconstructive techniques have been developed such as the autologous ear reconstruction technique using costal cartilage and ear reconstruction with high-density porous polyethylene or Medpor (Porex Surgical, Inc, College Park, GA). Autologous ear reconstructive techniques have advantages of durability and low infection rates however are associated with poorer aesthetic outcomes such as poor projection of the ear. Medpor has advantages of a more consistent three-dimensional definition without the need to harvest costochondral cartilage and create a donor site. However, due to its alloplastic material properties, Medpor has historically been reported as having a higher rate of extrusion and infection. This is the first systematic review to compare the outcomes of both techniques. The 6 studies that were reviewed were analyzed against 3 evaluative criteria: aesthetic outcome, complication rate, and convenience of intervention. This is so a comprehensive, evidence-based decision can be made by the surgeon and patient when ear reconstruction is required. The results showed heterogeneity in data and a lack of detailed descriptions of the assessment for aesthetic outcomes and convenience, hence were inconclusive. The results however showed that there were more complications with Medpor framework with 15% of total cases resulting in either extrusion or infection compared to 2% of autologous ear reconstruction framework.

Clinical Study of Hydroxyapatite-Based Eye Socket Filler in Surgery

An irreversible injury of the eyeball requires patients to undergo enucleation or enucleation of the contents of the eyeball. Due to the absence of organs in the eye socket, its collapse, the drooping of the upper eyelid, and possibility of an eyeball excision syndrome make severe facial deformity frequently occurs. To analyze the effect of applying hydroxyapatite (HA) materials in an eye socket filling surgery, patients requiring the surgery were recruited in this study and divided into two groups according to different eye prostheses selected by patients. Nano-HA orbital implantation was selected in the HA group, and porous high-density polyethylene was selected in the PE group. The activity of the artificial eye platform and Visual Analogue Scale scores were significant difference in both groups. Nevertheless, in the HA group, the total complication rate was lower, and the postoperative facial satisfaction was higher, all P &lt; 0.05. Therefore, it is speculated that the use of nano-HA as an eye socket filling material in an eye socket filling surgery reduces postoperative complications, improves the appearance to a certain extent, and has clinical application value.

A Staged Approach for Contouring of Temporal Deformities Using Porous Polyethylene and Lipofilling.

Many studies evaluated the effectiveness of a single reconstructive material during temporal cranioplasty, or in comparison to the outcome of another material. To our knowledge, no previous study evaluated a staged combination of reconstruction modalities during temporal cranioplasty. In a prospective interventional study, the authors combined high-density porous polyethylene (HDPP) implant insertion (stage I) with a following lipofilling session (stage II) in 8 patients scheduled for temporal cranioplasties. This two-staged approach was evaluated 6 months after each stage independently. The patients' satisfaction as regards the aesthetic outcome was evaluated through a 5-points Likert scale by the patients themselves. For every individual patient, this psychometric analysis was repeated by medical staff from other departments. Statistical analysis of the patients and medical staff satisfaction scores showed a statistically significant increase after the addition of lipofilling session (stage II) if compared to implant insertion only (stage I). Clinically, this outcome was maintained in a long-term follow-up ranged from 1 - 8 years. Nevertheless, 2 patients needed one more lipofilling session to obtain their satisfaction as regards the final aesthetic outcome. No other complications were recorded in this study. In conclusion, combining alloplastic and autogenous reconstruction modalities in a staged approach can suffice the reconstruction requirements for such temporal defects. After a long follow-up period, the insertion of high-density porous polyethylene implant with the addition of a following lipofilling session showed more evaluators' satisfaction in terms of the final aesthetic outcome.

Juvenile Ossifying Fibroma: Multiportal Endoscopic Trans-Nasal and Orbital Surgical Approaches, Histopathological and Radiological Findings

Abstract: Ossifying fibroma of the nasal cavity and paranasal sinus is a benign tumor histologically, however clinically may show invasive characteristics. It has malignancy rate of 0.4–0.5%. Here, we presented a 2 rare cases of Ossifying fibroma in two female children with Juvenile ossifying fibroma of the paranasal sinuses with orbital involvement and reviewed the literature of this rare tumour. Both cases subjected to complete ENT and ophthalmological examination and investigated by CT study of the paranasal sinuses, orbit and brain using specific protocol. Both underwent excision of the lesions as much as accessible and applicable to avoid complications and morbidity through combined trans-nasal endoscopic and orbital approaches with repair of the orbital wall with titanium as in first case and high-density porous polyethylene sheets as in the second case. We did report some minor post-operative complications. Post-operative follow up included complete ENT and ophthalmological examination and Follow up CT. A histopathological feature of the first case is consistent with diagnosis of trabecular variant of ossifying fibroma, while the second case is consistent with the diagnosis of psammomatoid variant of ossifying fibroma. Radilogically there were partially defined expansile heterogeneous fibro-osseous mass with ground glass appearance occupying the right maxillary, ethmoidal sinuses, and the right nasal cavity and invading the orbit. Conclusion: The diagnosis of JOF is made by correlation of clinical, radiological, histopathological findings. A combined Trans- Nasal endoscopic and orbital approach is effective for adequate excision. Key Words: ossifying fibroma; juvenile aggressive ossifying fibroma; fibro-osseous lesion.

Additive manufacturing enables personalised porous high-density polyethylene surgical implant manufacturing with improved tissue and vascular ingrowth

Porous high-density polyethylene (pHDPE) surgical implants have played a significant role in aesthetic, reconstructive and skeletal augmentation procedures for more than 30 years and have been the gold-standard synthetic implant used in more than 400,000 procedures worldwide. The effects of pHDPE implant properties such as porosity, geometry and surface chemistry are crucial considerations. Additive manufacturing and plasma surface treatment are promising approaches to induce rapid tissue integration and vascularisation, improve healing times and lead to more satisfactory patient outcomes. Here, a novel pHDPE scaffold architecture obtained by laser sintering was characterised to quantify porosity variations as a result of manufacturing, compared to scaffolds manufactured via traditional moulding, laser sintering, and the clinical gold-standard surgical implant, MEDPORⓇ. Plasma surface treatment was also explored as a means of improving the hydrophilicity of the HDPE. An in vitro cell culture study examined the attachment of cells on treated and non-treated scaffolds. After 3 days, plasma-treated scaffolds exhibited a 1.6-fold increase in cell attachment compared to non-treated, hydrophobic samples. Plasma-treated and non-treated samples were then implanted subcutaneously in rats for 1, 4, and 8 weeks to assess biocompatibility, tissue ingrowth and vascularisation. Histological analysis revealed that laser sintered StarPoreⓇ scaffolds exhibited significantly higher tissue ingrowth compared to the moulded scaffolds, whilst fibrous encapsulation dominated the tissue response in moulded StarPoreⓇ scaffolds. Plasma treatment did not significantly affect the quantity of tissue ingrowth, however it significantly increased the density of blood vessels within sintered StarPoreⓇ scaffolds by an average of 86.6%. Overall, this study demonstrated that novel manufacturing and plasma treatment of pHDPE surgical implants enhanced cell attachment in vitro and increased blood vessel density in laser sintered StarPoreⓇ scaffolds in vivo.

Complications of Alloplast Rhinoplasty and Their Management: A Comprehensive Review.

In Asian countries, augmentation rhinoplasty is especially common, where alloplastic implants are used much more commonly than autologous tissues. In rhinoplasty, such artificial materials include silicone, expanded polytetrafluoroethylene (ePTFE), porous high-density polyethylene (pHDPE), and acellular human dermis. As the use of implants has become increasingly common in rhinoplasty, more adverse effects such as infection, extrusion, movement, irregularities, absorption, prolonged swelling, seroma, and contracture have been recognized and reported in the literature. Surgeons should be able to recognize these probable complications and manage them successfully. Early detection and prompt management of the complication are essential for minimizing the severity of the deformity. Proper management of complications is key for the success of dorsal augmentation using alloplastic implants.

Standard and Customized Alloplastic Facial Implants Refining Orthognathic Surgery: Outcome Evaluation

Conventional orthognathic osteotomies provide appropriate functional outcomes but might be unable to correct midface deficiency, achieve a satisfactory outcome in asymmetrical cases, or allow sufficient chin advancement. We evaluated the outcome of both standard and customized facial high-density porous polyethylene implants used to refine the cosmetic outcome of orthognathic surgery. We implemented a retrospective study. The sample was composed of all patients who underwent facial alloplastic augmentation between June 2011 and October 2018 in our department. The complication rate was recorded after a mean follow-up period of 41months postoperatively, and patient satisfaction was assessed through a qualitative evaluation based on an 11-item questionnaire. The sample was composed of 24 implants placed in 14 patients: 13 mandibular angle implants, among which 4 were customized; 8 malar implants; and 3 chin implants. No physical complications such as hematoma, infection, migration, or hypoesthesia were observed. Two implants had to be removed because of early unsatisfactory esthetic outcomes. Of 14 patients, 11 answered our questionnaire. Eighty-two percent strongly agreed that the overall outcome was satisfactory. The results of this study confirm the low physical complication rate described in the literature, and the esthetic complication rate remains lower than the rates observed in previous reports. A high satisfaction rate was found among patients. The lowest mean satisfaction score was noted for appropriate implant symmetry (3.5), whereas the highest mean satisfaction score (3.8) was achieved when using customized implants. If standard high-density porous polyethylene implants appear to be relevant adjuncts to orthognathic surgery, customized implants seem to achieve higher satisfaction, although their prohibitive cost should be considered.

The Effect of Perichondrium on Biological and Biomechanical Properties of Molded Diced Cartilage Grafts.

Diced cartilage is a significant alternative approach to cartilage grafting. However, the viability and biomechanical properties of diced cartilage grafts remain to be improved, and the role of perichondrium is largely neglected. This study aimed to evaluate the histological and biomechanical effects of perichondrium on custom-shaped diced cartilage grafts constructed via a high-density porous polyethylene mold. Seven New Zealand rabbits were used. Unilateral auricular cartilage was harvested and divided into 2 parts, with or without perichondrium, diced into 1 × 1 × 0.5mm cubical pieces, and filled into high-density porous polyethylene molds. Three grafts with the perichondrium removed and 3 with the perichondrium preserved were implanted subcutaneously at the dorsum. The grafts underwent biomechanical and histological tests 4, 8, and 12weeks after the implantation. The diced cartilage merged into integrated blocks without observable resorption in both groups at each time point. Additionally, the retention rate of weight was higher in the perichondrium-preserved group (P < 0.05). We observed regenerated cartilage that stained positively for type II collagen and glial fibrillary acidic protein (GFAP). A greater area of regenerated cartilage and higher scores of GFAP staining were observed in the perichondrium-preserved group (P < 0.05). The yield stress and modulus of elasticity were also higher in the perichondrium-preserved grafts from week 8 after implantation (P < 0.05). Diced cartilage grafts with a custom shape can be constructed using a high-density porous polyethylene mold. The preservation of perichondrium can improve graft viability and biomechanical properties. This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266.