Treatment of orbital floor fracture using a periosteum–polymer complex

A systematic literature review and narrative synthesis on the use of autologous cartilage in the repair of orbital fractures

Introduction

Fractures of the orbit are common injuries within the maxillofacial skeleton, and can often result in restrictions to ocular movement, diplopia, and enophthalmous if herniation of globe content occurs. Various studies have demonstrated the use of autologous cartilage grafts in the reconstruction of orbital fractures.

Methods

A systematic review protocol was registered with PROSPERO, and reported in accordance with the Preferred Reporting for Items for Systematic Reviews and Meta-Analyses. Comprehensive electronic search strategies of four databases were developed. Studies were screened according to the inclusion and exclusion criteria by two independent reviewers.

Results

Seven thousand one hundred seventy-one articles were identified following a comprehensive literature search. These articles were filtered for relevance and duplication, which reduced the number of articles to 16. A total of 259 patients underwent orbital reconstruction with the use of autologous cartilage. Conchal cartilage was harvested in 148 patients, auricular cartilage in 22 patients, nasoseptal cartilage in 72 patients, and costal cartilage in 17 patients. Thirty, seven, twelve, and four complications were observed in patients where cartilage was harvested from the concha, auricle, nasoseptum and rib, respectively. Most common complications included diplopia (n=23), infra-orbital para/anaesthesia (n=27), and enophthalmos (n=7). No failure of graft or donor site morbidity were observed in the studies.

Conclusion

Autogenous materials such as cartilage can be used as an alternative for orbital reconstruction. Cartilage was considered by the authors to provide adequate structural support to the orbital contents, and that it was easy to harvest, shape, and position.

The Use of Functional Biomaterials in Aesthetic and Functional Restoration in Orbital Surgery

The integration of functional biomaterials in oculoplastic and orbital surgery is a pivotal area where material science and clinical practice converge. This review, encompassing primary research from 2015 to 2023, delves into the use of biomaterials in two key areas: the reconstruction of orbital floor fractures and the development of implants and prostheses for anophthalmic sockets post-eye removal. The discussion begins with an analysis of orbital floor injuries, including their pathophysiology and treatment modalities. It is noted that titanium mesh remains the gold standard for orbital floor repair due to its effectiveness. The review then examines the array of materials used for orbital implants and prostheses, highlighting the dependence on surgeon preference and experience, as there are currently no definitive guidelines. While recent innovations in biomaterials show promise, the review underscores the need for more clinical data before these new materials can be widely adopted in clinical settings. The review advocates for an interdisciplinary approach in orbital surgery, emphasizing patient-centered care and the potential of biomaterials to significantly enhance patient outcomes.

Automatic orbital segmentation using deep learning-based 2D U-net and accuracy evaluation: A retrospective study

The purpose of this study was to verify whether the accuracy of automatic segmentation (AS) of computed tomography (CT) images of fractured orbits using deep learning (DL) is sufficient for clinical application. In the surgery of orbital fractures, many methods have been reported to create a 3D anatomical model for use as a reference. However, because the orbit bone is thin and complex, creating a segmentation model for 3D printing is complicated and time-consuming. Here, the training of DL was performed using U-Net as the DL model, and the AS output was validated with Dice coefficients and average symmetry surface distance (ASSD). In addition, the AS output was 3D printed and evaluated for accuracy by four surgeons, each with over 15 years of clinical experience. One hundred twenty-five CT images were prepared, and manual orbital segmentation was performed in all cases. Ten orbital fracture cases were randomly selected as validation data, and the remaining 115 were set as training data. AS was successful in all cases, with good accuracy: Dice, 0.860 ± 0.033 (mean ± SD); ASSD, 0.713 ± 0.212 mm. In evaluating AS accuracy, the expert surgeons generally considered that it could be used for surgical support without further modification. The orbital AS algorithm developed using DL in this study is extremely accurate and can create 3D models rapidly at low cost, potentially enabling safer and more accurate surgeries.

The Statistical Fragility of Orbital Fractures: A Systematic Review of Randomized Controlled Trials

BACKGROUND

The P value has often been used as a tool to determine the statistical significance and evaluate the statistical robustness of study findings in orthopedic literature. The purpose of this study is to apply both the fragility index (FI) and the fragility quotient (FQ) to evaluate the degree of statistical fragility in orbital fracture literature. We hypothesized that the dichotomous outcomes within the orbital fracture literature will be vulnerable to a small number of outcome event reversals and will be statistically fragile.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), the authors identified all dichotomous data for randomized controlled trials (RCTs) in orbital fracture literature and performed a PubMed search from 2000 to 2022. The FI of each outcome was calculated through the reversal of a single outcome event until significance was reversed. The FQ was calculated by dividing each FI by study sample size. The interquartile range (IQR) was also calculated for the FI and FQ.

RESULTS

Of the 3,329 studies screened, 28 met the criteria with 10 RCTs evaluating orbital fractures included for analysis. A total of 58 outcome events with 22 significant (P < .05) outcomes and 36 nonsignificant (P ≥ .05) outcomes were identified. The overall FI and FQ for all 58 outcomes was 5 (IQR: 4 to 5) and 0.140 (IQR: 0.075 to 0.250), respectively. Fragility analysis of statistical significant outcomes and nonsignificant outcomes had an FI of 3.5 with no IQR and 5 (IQR 4-5), respectively. All of the studies reported a loss to follow-up data, where 20% (2) was greater than the overall FI of 5.

CONCLUSION

The orbital fracture literature provides treatment guidance by relying on statistical significant results from RCTs. However, the RCTs in the orbital fracture peer-reviewed literature may not be statistically stable as previously thought. The sole reliance of the P value may depict misleading results. Thus, we recommend standardizing the reporting of the P value, FI, and FQ in the orbital fracture literature to aid readers in reliably drawing conclusions based on fragility outcome measures impacting clinical decision-making.

The Prrx1eGFP Mouse Labels the Periosteum During Development and a Subpopulation of Osteogenic Periosteal Cells in the Adult

The identity of the cells that form the periosteum during development is controversial with current dogma suggesting these are derived from a Sox9-positive progenitor. Herein, we characterize a newly created Prrx1eGFP reporter transgenic mouse line during limb formation and postnatally. Interestingly, in the embryo Prrx1eGFP-labeled cells become restricted around the Sox9-positive cartilage anlage without themselves becoming Sox9-positive. In the adult, the Prrx1eGFP transgene live labels a subpopulation of cells within the periosteum that are enriched at specific sites, and this population is diminished in aged mice. The green fluorescent protein (GFP)-labeled subpopulation can be isolated using fluorescence-activated cell sorting (FACS) and represents approximately 8% of all isolated periosteal cells. The GFP-labeled subpopulation is significantly more osteogenic than unlabeled, GFP-negative periosteal cells. In addition, the osteogenic and chondrogenic capacity of periosteal cells in vitro can be extended with the addition of fibroblast growth factor (FGF) to the expansion media. We provide evidence to suggest that osteoblasts contributing to cortical bone formation in the embryo originate from Prrx1eGFP-positive cells within the perichondrium, which possibly piggyback on invading vascular cells and secrete new bone matrix. In summary, the Prrx1eGFP mouse is a powerful tool to visualize and isolate periosteal cells and to quantify their properties in the embryo and adult. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Collision of Commonality and Personalization: Better Understanding of the Periosteum

The periosteum is quite essential for bone repair. The excellent osteogenic properties of periosteal tissue make it a popular choice for accelerated osteogenesis in tissue engineering. With advances in research and technology, renewed attention has been paid to the periosteum. Recent studies have shown that the complexity of the periosteum is not only limited to histological features but also includes genetic and phenotypic features. In addition, the periosteum is proved to be quite site-specific in many ways. This brings challenges to the selection of periosteal donor sites. Limited understanding of the periosteum sets up barriers to developing optimal tissue regeneration strategies. A better understanding of periosteum could lead to better applications. Therefore, we reviewed the histological structure, gene expression, and function of the periosteum from both the commonality and personalization. It aims to discuss some obscure issues and untapped potential of periosteum and artificial periosteum in the application, where further theoretical research is needed. Overall, the site-specificity of the periosteum needs to be fully considered in future applications. However, significant further work is needed in relevant clinical trials to promote the further development of artificial periosteum.

The Dilemma of Reconstructive Material Choice for Orbital Floor Fracture: A Narrative Review

The aim of this study is to present a narrative review of the properties of materials currently used for orbital floor reconstruction. Orbital floor fractures, due to their complex anatomy, physiology, and aesthetic concerns, pose complexities regarding management. Since the 1950s, a myriad of materials has been used to reconstruct orbital floor fractures. This narrative review synthesises the findings of literature retrieved from search of PubMed, Web of Science, and Google Scholar databases. This narrative review was conducted of 66 studies on reconstructive materials. Ideal material properties are that they are resorbable, osteoconductive, resistant to infection, minimally reactive, do not induce capsule formation, allow for bony ingrowth, are cheap, and readily available. Autologous implants provide reliable, lifelong, and biocompatible material choices. Allogenic materials pose a threat of catastrophic disease transmission. Newer alloplastic materials have gained popularity. Consideration must be made when deliberating the use of permanent alloplastic materials that are a foreign body with potential body interactions, or the use of resorbable alloplastic materials failing to provide adequate support for orbital contents. It is vital that surgeons have an appropriate knowledge of materials so that they are used appropriately and reduce the risks of complications.

Clinical evaluation of the efficacy of materials used for primary reconstruction of orbital floor defects: Meta-analysis

BACKGROUND

The aim of this network meta-analysis (NMA) was to compare the clinical results obtained after primary reconstruction of orbital floor fractures (OFF) using different materials.

METHODS

PubMed, Cochrane, and Google Scholar databases were screened from 1989 to 2019. For a study to be eligible, it had to evaluate two or more materials and report the following clinical parameters: diplopia and/or enophthalmos and/or other complications.

RESULTS

Nine studies involving 946 patients presenting with an OFF were included. After the surgical procedure, 105 patients (11%) had diplopia, while 43 patients (4.5%) suffered from enophthalmos. The NMA revealed that less postoperative diplopia and enophthalmos were obtained either by using polydioxanone (PDS), or a polymer of l-lactic acid and dl-lactic acid (P[L/DL]LA), or porous polyethylene, or titanium mesh compared with the use of autologous bone grafts.

CONCLUSION

P(L/DL)LA and PDS seem to be the best options for small and intermediate defects, whereas the association of porous polyethylene and titanium should be preferred for larger defects.

Influence of Periosteum Location on the Bone and Cartilage in Tissue-Engineered Phalanx

PURPOSE

This study investigated the influence of periosteal tissue of different origins on the calcification at the diaphysis and chondrocyte maturation at the epiphysis in an engineered phalanx. We hypothesized that the periosteum from long bones would better provide donor cells for bone formation and signals for maturation of the joint cartilage.

METHODS

Periosteum was harvested from 4 locations (cranium, mandible, radius, and ilium) of calf bones. A human phalangeal bone-shaped, biodegradable, 3-dimensional scaffold hydroxyapatite-poly L-lactic-ɛ-caprolactone (HA-P[LA/CL]) was prepared using a human phalangeal bone-shaped template. A bioengineered human phalanx was fabricated by combining periosteal grafts with biodegradable copolymers. The joint cartilage region (chondrocyte/polyglycolic acid [PGA] composite) was subsequently sutured to the phalangeal bone region (periosteum/HA-P[LA/CL] composite) with absorbable sutures to make a human phalangeal bone model. These were then implanted in nude mice for maturation of the constructs. Macroscopic, radiographic, histological, and immune-histochemical evaluations were carried out to determine the relative influence of the periosteal graft source on bone and cartilage formation at 10 and 20 weeks after implantation.

RESULTS

Calcification localized under the periosteum was noted in the cranium, radius, and ilium groups after 10 weeks, which markedly expanded at the modelled diaphysis after 20 weeks. The width in the minor axis direction tended to increase with time after grafting in the cranium group, whereas the longitudinal length increased in the radius and ilium groups. The joint cartilage thickness changed with time depending on the type of periosteum, and periosteum collected from the radius and ilium was associated with the greatest cartilage thickness in the joint cartilage maturation process.

CONCLUSIONS

These results suggest that periosteum collected from radius of calves demonstrated superior bone formation and chondrocyte maturation in the engineered phalanx compared with other sources of periosteum.

CLINICAL RELEVANCE

The osteogenic capacity depends on the periosteal source regardless of intramembranous or endochondral ossification. The appropriate periosteal choice is essential in the phalangeal bone and cartilage tissue engineering. The results are important for broadening tissue engineering possibilities for clinical application.

Wrapping grafting for congenital pseudarthrosis of the tibia: A preliminary report

OBJECTIVE

Treatment of congenital pseudarthrosis of the tibia (CPT) remains a challenge. The autogenic iliac bone graft is important consistent of treatment for CPT. The purpose of this study was to investigate the role of wrapping autogenic iliac bone graft in improvement of the curing opportunities of CPT.

METHODS

We combined Ilizarov fixator with intramedullary rodding of the tibia and wrapping autogenic iliac bone graft for treatment 51 cases of CPT between 2007 and 2010. The mean age is 3.2 years at index operation, of which 31 patients (61%) were below 3 years old. According to Crawford classification, 5 tibia had type-II morphology; 3, type-III; 43, type-IV.

RESULTS

In the postoperative follow-up of 3.5 months (range from 3 to 4.5 months), all cases were found that the bone graft sites of pseudarthrosis of the tibia showed a significant augmentation and spindle-shaped expansion as obvious change. All cases of this series have been followed-up, average followed-up time were 1.6 years (range from 7 to 3.1 years), of which 19 cases were more than 2 years. The average time of removed the Ilizarov ring fixator was 3.5 months (range from 3 to 4.5 months). According to Johnston Clinical evaluation system, 26 cases had grade I, 21 cases, grade II, 4 cases, grade III. Following the Ohnishi X-ray evaluation criteria, union of pseudarthrosis of the tibia were 42 cases, delayed union 5 cases, nonunion 4 cases.

CONCLUSION

Autogenic iliac bone graft is able to offer the activity of osteoblasts and osteogenesis induced by bone morphogenetic protein (BMP) and glycoprotein, meanwhile enclosing bone graft could help keep cancellous bone fragments in close contact around pseudarthrosis of the tibia, allowing the formation of high concentration of glycoprotein and BMP induced by chemical factors because of established the sealing environment in location, all of which could enhance the healing of pseudarthrosis of the tibia.

Scapular Bone Grafts: Good Options for Craniofacial Defects?

INTRODUCTION

There is still no consensus on the ideal material to be used in craniofacial defects. Autogenous bone grafts are mostly preferred owing to their use with fewer complications. The aim of this study was to evaluate whether the scapular bone graft can be used with equal or more advantages to other bone graft resources in orbital, maxillary sinus front wall, and frontal bone defects.

PATIENTS AND METHODS

Twenty-four orbital, maxillary sinus front wall, and frontal bone defects were reconstructed with scapular bone grafts. Sixteen patients presented with complicated orbital fractures, 5 patients presented with isolated orbital floor fractures, and 3 patients presented with frontal bone fractures. The grafts were radiologically evaluated 1 day, 6 months, and 12 months postoperatively by 3-dimensional computed tomography scan.

RESULTS

All orbital, maxillary sinus front wall, and frontal bone defects were reconstructed successfully with scapular bone grafts. Clinical evaluation of the patients at 6 to 24 months of follow-up was considered satisfactory. Minimal donor site morbidity was observed. Scapular bone grafts adapted nicely to the recipient area, and bony union was complete as demonstrated by 3-dimensional computed tomography scans.

CONCLUSIONS

Reconstruction of orbital, maxillary sinus front wall, and frontal bone defects with scapular bone grafts is an easy and safe procedure with minimal donor site morbidity. Scapular bone graft is a good reconstructive option for orbital, maxillary sinus front wall, and frontal bone defects.

Bioceramics in ophthalmology

The benefits of ceramics in biomedical applications have been universally appreciated as they exhibit an extraordinarily broad set of physico-chemical, mechanical and biological properties which can be properly tailored by acting on their composition, porosity and surface texture to increase their versatility and suitability for targeted healthcare applications. Bioceramics have traditionally been used for the repair of hard tissues, such as bone and teeth, mainly due to their suitable strength for load-bearing applications, wear resistance (especially alumina, zirconia and composites thereof) and, in some cases, bone-bonding ability (calcium orthophosphates and bioactive glasses). Bioceramics have been also applied in other medical areas, like ophthalmic surgery; although their use in such a context has been scientifically documented since the late 1700s, the potential and importance of ceramic ocular implants still seem to be underestimated and an exhaustive, critical assessment is currently lacking in the relevant literature. The present review aims to fill this gap by giving a comprehensive picture of the ceramic-based materials and implants that are currently used in ophthalmology and pointing out the strengths and weaknesses of the existing devices. A prospect for future research is also provided, highlighting the potential of new, smart bioceramics able to carry specific added values which could have a significant impact on the treatment of ocular diseases.

Biomaterials for repair of orbital floor blowout fractures: a systematic review

PURPOSE

To evaluate the reported use and outcomes of implant materials used for the restoration of post-traumatic orbital floor defects in adults.

MATERIALS AND METHODS

A systematic search of the English literature was performed in the databases of PubMed, Cochrane Library, and EMBASE. The study selection process was adapted from the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement, and 55 articles complied with the study inclusion criteria. The primary outcome measures were diplopia, enophthalmos, graft extrusion/displacement, and infection related to the graft material. The secondary outcome measures were infraorbital paresthesia, orbital dystopia, orbital soft tissue entrapment, and donor-site complications.

RESULTS

Of 55 articles, 41 (74.5%) evaluated were retrospective case series, 9 (16.4%) were retrospective case-control studies, 3 (5.5%) were controlled trials, and 2 (3.6%) were prospective case series. Autogenous graft materials were predominantly used in 19 studies, alloplastic materials were used in 33 studies, and the remaining 3 articles reported on allogeneic materials. Overall, 19 different types of implant materials were used in 2,483 patients. Of 827 patients with diplopia before surgery, 151 (18.3%) had diplopia postoperatively. Of 449 patients with enophthalmos before surgery, 134 (29.8%) had enophthalmos postoperatively. Only 2 patients (0.1%) and 14 patients (0.6%) had graft extrusion/displacement and infection related to the graft material, respectively; alloplastic biomaterials were used in all of these cases.

CONCLUSIONS

All graft materials used were successful to variable degrees because all studies reported improvement in terms of the recorded outcome measures. A guideline for choice of implant material based on defect size was developed.

Application of scaffolds for bone regeneration strategies: current trends and future directions

Scaffolds are extensively used in surgery to replace missing bone and to achieve bony union and fusion. An ideal scaffold should not only maintain, induce, and restore biological functions where cells, extracellular matrix, and growth factors are needed, but also have the right properties with respect to degradation, cell binding, cellular uptake, non-immunogenicity, mechanical strength, and flexibility. Here we examine both the basic science behind the development of scaffolds and comprehensively and systematically review the clinical applications.

The signaling and functions of heterodimeric bone morphogenetic proteins

Heterodimeric bone morphogenetic proteins (BMPs) consist of disulfide-linked dimeric monomers derived from different BMP members. Owing to this specific constitution pattern, they bear high affinity to both type I and type II BMP receptors simultaneously. Meanwhile, the antagonism efficiency of extracellular antagonists to heterodimeric BMPs is also significantly lower than that to homodimeric ones. All these specific properties confer heterodimeric BMPs with distinct signaling and bio-functions that are characterized by more speediness, lower concentration/dose threshold and higher efficiency than homodimeric BMPs. Consequently, heterodimeric BMPs bear promising application potential in inducing osteogenesis. In addition, they may play indispensible roles in organogenesis. In this review, we summarize the current knowledge of heterodimeric BMPs in their signaling pathways and bio-functions.

Forces charging the orbital floor after fractures

The objective of this study was first to establish a method to measure forces and displacement of the orbital content in defects of the orbital floor in truncated fresh and unfixed heads and second to characterize reconstruction materials with regard to punctuation strength and compression.Orbital floor defects (10 × 20 mm and 15 × 20 mm; 3 mm behind the orbital rim) were prepared after Le Fort I osteotomy. The values of force and displacement were recorded in 6 freshly frozen human heads. In addition, the punctuation strength of 2 reconstruction materials (polydioxanone [PDS] foil and collagen membrane) was evaluated using a Zwick Z010 TN1 universal testing machine. The forces of the orbital content (28.41 [SD, 1.6] g) applied to the defects of 10 × 20 mm and 15 × 20 mm with an intact periorbita were 0.04 (SD, 0.003) N (0.0002 MPa) and 0.07 (SD, 0.02) N (0.0002 MPa), respectively, and with a split periorbita were 0.06 (SD, 0.03) N (0.0003 MPa) and 0.08 (SD, 0.06) N (0.00026 MPa), respectively. The displacement values without reconstruction materials of the 10 × 20-mm and 15 × 20-mm defects were 0.94 (SD, 0.7) mm and 1.2 (SD, 0.5) mm, respectively. The PDS foil could withstand forces of 118.9 (SD, 14.1) N (0.375 MPa), and the collagen membrane could withstand forces of 44.5 (SD, 5.3) N (0.14 MPa). This is the first study to report forces charging the orbital floor. The presented results support the use of PDS foils and collagen membranes as reconstruction materials for orbital floor defects, at least in smaller and medium-sized fractures.

Biomaterials and implants for orbital floor repair

Treatment of orbital floor fractures and defects is often a complex issue. Repair of these injuries essentially aims to restore the continuity of the orbital floor and to provide an adequate support to the orbital content. Several materials and implants have been proposed over the years for orbital floor reconstruction, in the hope of achieving the best clinical outcome for the patient. Autografts have been traditionally considered as the "gold standard" choice due to the absence of an adverse immunological response, but they are available in limited amounts and carry the need for extra surgery. In order to overcome the drawbacks related to autografts, researchers' and surgeons' attention has been progressively attracted by alloplastic materials, which can be commercially produced and easily tailored to fit a wide range of specific clinical needs. In this review the advantages and limitations of the various biomaterials proposed and tested for orbital floor repair are critically examined and discussed. Criteria and guidelines for optimal material/implant choice, as well as future research directions, are also presented, in an attempt to understand whether an ideal biomaterial already exists or a truly functional implant will eventually materialise in the next few years.

Update on orbital reconstruction

PURPOSE OF REVIEW

Orbital trauma is common and frequently complicated by ocular injuries. The recent literature on orbital fracture is analyzed with emphasis on epidemiological data assessment, surgical timing, method of approach and reconstruction materials.

RECENT FINDINGS

Computed tomographic (CT) scan has become a routine evaluation tool for orbital trauma, and mobile CT can be applied intraoperatively if necessary. Concomitant serious ocular injury should be carefully evaluated preoperatively. Patients presenting with nonresolving oculocardiac reflex, 'white-eyed' blowout fracture, or diplopia with a positive forced duction test and CT evidence of orbital tissue entrapment require early surgical repair. Otherwise, enophthalmos can be corrected by late surgery with a similar outcome to early surgery. The use of an endoscope-assisted approach for orbital reconstruction continues to grow, offering an alternative method. Advances in alloplastic materials have improved surgical outcome and shortened operating time.

SUMMARY

In this review of modern orbital reconstruction, several controversial issues such as surgical indication, surgical timing, method of approach and choice of reconstruction material are discussed. Preoperative fine-cut CT image and thorough ophthalmologic examination are key elements to determine surgical indications. The choice of surgical approach and reconstruction materials much depends on the surgeon's experience and the reconstruction area. Prefabricated alloplastic implants together with image software and stereolithographic models are significant advances that help to more accurately reconstruct the traumatized orbit. The recent evolution of orbit reconstruction improves functional and aesthetic results and minimizes surgical complications.

Accelerated osteomesh resorption: a case report

Facial fractures occur commonly as a result of blunt trauma from road traffic accidents, assaults, and sporting injuries. Orbital floor fractures form a significant proportion of these and when large enough, the defect often requires surgical reconstruction of the floor to prevent orbital content herniation. Here, we present a case of a 28-year-old gentleman, who sustained an orbital floor fracture from a soccer-related injury. The resulting floor defect was surgically repaired using an osteomesh that was hand-cut to size. He developed delayed enophthalmos and entrapment of the inferior rectus muscle due to early resorption of the osteomesh, requiring revision surgery.

Biomimetic coatings for bone tissue engineering of critical-sized defects

The repair of critical-sized bone defects is still challenging in the fields of implantology, maxillofacial surgery and orthopaedics. Current therapies such as autografts and allografts are associated with various limitations. Cytokine-based bone tissue engineering has been attracting increasing attention. Bone-inducing agents have been locally injected to stimulate the native bone-formation activity, but without much success. The reason is that these drugs must be delivered slowly and at a low concentration to be effective. This then mimics the natural method of cytokine release. For this purpose, a suitable vehicle was developed, the so-called biomimetic coating, which can be deposited on metal implants as well as on biomaterials. Materials that are currently used to fill bony defects cannot by themselves trigger bone formation. Therefore, biological functionalization of such materials by the biomimetic method resulted in a novel biomimetic coating onto different biomaterials. Bone morphogenetic protein 2 (BMP-2)-incorporated biomimetic coating can be a solution for a large bone defect repair in the fields of dental implantology, maxillofacial surgery and orthopaedics. Here, we review the performance of the biomimetic coating both in vitro and in vivo.

Comparison of conchal cartilage graft with nasal septal cartilage graft for reconstruction of orbital floor blowout fractures

Our aim was to compare autogenous nasal septal cartilage and conchal cartilage as grafts for reconstruction of orbital blowout fractures. Twenty-two patients with blowout fractures were randomly assigned to two groups for treatment with a graft of nasal septal cartilage or conchal cartilage. Patients were evaluated for the presence of enophthalmos, diplopia, dysfunction of the infraorbital nerve, and restriction of the ocular muscles. Patients with enophthalmos of more than 2 mm were included in the study, and were followed up postoperatively at 10 days, 1 month, and 3-6 months. The patients treated with a nasal septal cartilage graft had significantly better correction of enophthalmos than those treated with conchal cartilage (p=0.02) after 10 days (p=0.02), 1 month (p=0.004), and 3-6 months (p=0.001). There was significantly less residual enophthalmos in the nasal septal graft group after 1 month (0.91 compared with 1.72 mm, p=0.02), and after 3-6 months (1.0 compared with 2.54 mm, p=0.008). Correction of enophthalmos was considerably better in patients who were operated on within 4 weeks of injury. We think that nasal septal cartilage is a better graft than conchal cartilage for reconstruction of blowout fractures. The time to intervention (the earlier the better) is a critical point in the correction of enophthalmos.