Biomaterials for reconstruction of the internal orbit

Classical Orbital Floor Post-Traumatic Reconstruction vs. Customized Reconstruction with the Support of "In-House" 3D-Printed Models: A Retrospective Study with an Analysis of Volumetric Measurement

BACKGROUND

Orbital floor fractures (OFFs) represent an interesting chapter in maxillofacial surgery, and one of the main challenges in orbit reconstruction is shaping and cutting the precise contour of the implants due to its complex anatomy.

OBJECTIVE

The aim of the retrospective study was to demonstrate, through pre- and postoperative volumetric measurements of the orbit, how the use of a preformed titanium mesh based on the stereolithographic model produced with 3D printers ("In-House" reconstruction) provides a better reconstruction volumetric compared to the intraoperatively shaped titanium mesh.

MATERIALS AND METHODS

The patients with OFF enrolled in this study were divided into two groups according to the inclusion criteria. In Group 1 (G1), patients surgically treated for OFF were divided into two subgroups: G1a, patients undergoing orbital floor reconstruction with an intraoperatively shaped mesh, and G1b, patients undergoing orbital floor reconstruction with a preoperative mesh shaped on a 3D-printed stereolithographic model. Group 2 (G2) consisted of patients treated for other traumatic pathologies (mandible fractures and middle face fractures not involving orbit). Pre- and postoperative orbital volumetric measurements were performed on both G1 and G2. The patients of both groups were subjected to the measurement of orbital volume using Osirix software (Pixmeo SARL, CH-1233 Bernex, Switzerland) on the new CT examination. Both descriptive (using central tendency indices such as mean and range) and regressive (using the Bravais-Pearson index, calculated using the GraphPad program) statistical analyses were performed on the recorded data.

RESULTS

From 1 January 2017 to 31 December 2021, of the 176 patients treated for OFF at the "Magna Graecia" University Hospital of Catanzaro 10 fulfilled the study's inclusion criteria: 5 were assigned to G1a and 5 to G1b, with a total of 30 volumetric measurements. In G2, we included 10 patients, with a total of 20 volumetric measurements. From the volumetric measurements and statistical analysis carried out, it emerged that the average of the volumetric differences of the healthy orbits was ±0.6351 cm3, the standard deviation of the volumetric differences was ±0.3383, and the relationship between the treated orbit and the healthy orbit was linear; therefore, the treated orbital volumes tend to approach the healthy ones after surgical treatment.

CONCLUSION

This study demonstrates that if the volume is restored within the range of the standardized mean, the diplopia is completely recovered already after surgery or after one month. For orbital volumes that do not fall within this range, functional recovery could occur within 6 months or be lacking. The restoration of the orbital volume using pre-modeled networks on the patient's anatomical model, printed internally in 3D, allows for more accurate reconstructions of the orbital floor in less time, with clinical advantages also in terms of surgical timing.

Acellular cadaveric dermal matrix grafts for orbital wall reconstruction in patients with sinonasal malignancies

PURPOSE

To describe the utilization of acellular cadaveric dermal matrix (ACDM) in patients undergoing orbital wall reconstruction after orbital preservation surgery for sinonasal malignancy.

METHODS

Retrospective case series of seven patients with sinonasal malignancy who had orbital reconstruction with ACDM implants from January 2012 to August 2020. Orbital preservation was performed in all patients with tumor extension up to and including periorbital. The main outcome measures were implant exposure, orbital infection, diplopia in primary gaze, enophthalmos, and eyelid malposition.

RESULTS

Patients ranged 37-78 years old (median: 66 years) and included 4 females and 3 males. The median follow-up time was 9 months (range 6-43 months) from the date of surgery. Squamous cell carcinoma comprised the majority of tumors with all patients needing medial wall reconstruction. Three patients received postoperative radiation therapy. No patients had any implant exposure, orbital infection, enophthalmos, or eyelid malposition.

CONCLUSIONS

ACDM grafts can be used safely in orbital wall reconstruction in patients with sinonasal malignancies.

Management of Orbital Floor Fractures: Our Experience in 10 Years

Purpose

Orbital floor Fractures are the most common fractures involving the facial skeleton and usually occurs after traumatic events. The reconstruction of the orbital floor can be performed with different biocompatible materials. The aim of our retrospective study is to analyze the short- and long-term outcomes of surgically treated patients based on the material used to repair the orbital floor.

Methods

We enrolled 146 patients hospitalized for orbital floor fractures in the Maxillofacial Surgery Unit of the Federico II University of Naples from 1 to 2010 to July 2020. All the fractured orbital floors were reconstructed with non-resorbable (Titanium Mesh, SynPor, SuPor and MedPor implants) or resorbable (collagen membrane, bovinum pericardium membrane, autologous bone graft) materials.

Results

We utilized non-resorbable materials in 56% (82 cases) and resorbable implants in 44% (64 cases). An improvement of the preoperative symptomatology and an aesthetical good outcome was achieved in most cases.

Conclusions

Data obtained supports that both resorbable and non-resorbable materials for orbital floor reconstruction are a safe and effective alternatives and offer satisfactory results in functional and aesthetic evaluations.

PDS Plate Versus Bone Graft in Orbital Floor Reconstruction: A Prospective Study to Identify the Better Alternative

The objective of this study is to compare the effect and outcome of orbital floor reconstruction with bone graft and PDS plate. A prospective cohort study was conducted at B J Medical College, Civil Hospital, Ahmedabad from 1st September 2013 to 28th February 2016 by the Department of Burns and Plastic Surgery on patients (N = 35) who reported with orbital floor fracture. Diplopia, enophthalmos, infection rate, hospital stay, and donor site complications were considered. The above variables were assessed as predictors of outcome in the management (PDS vs. bone graft). Inferential statistics was done by chi-square test. The significance level was kept at 5%. Follow-up of 35 patients (2 years), 26 male, and 9 females aged 26-65 years were made. Diplopia and enophthalmos were the main criteria's in the study and neither of them showed any statistical significance. Donor site morbidity was noted in 3 patients among the bone graft group which was managed conservatively. Both the bone graft and PDS plate in orbital floor reconstruction is comparable in almost all aspects of our study. No statistically significant differences were found between the two groups. Pain and wound site infection are possible complications when a bone graft is used as the reconstructive option.

Evaluation of a New Porcine Bone Graft on the Repair of Surgically Created Critical Bone Defects in Rat Calvaria: Histomorphometric and Microtomographic Study

The aim of this study was to evaluate the use of a new porcine bone graft in rat calvaria bone defects. Critical defects were surgically created in 24 rats that were divided into four experimental groups according to defect filling (n = 6): Control Group (CG)—blood clot; Porcine Bone Group (PG)—porcine-derived bone substitute; (BG): Bio-Oss Group (BG)−chemically and heat-treated bovine graft; Bonefill Group (BFG)—chemically treated bovine bone substitute. Euthanasia of the animals occurred 30 days after the surgery, and the area of the original surgical defect and the surrounding tissues were removed for micro-CT and histomorphometric analysis. In the micro-CT evaluation, the PG presented statistically significant differences (p < 0.05) in comparison to the CG, BG and BFG, for the parameters percentage of Bone Volume (BV/TV), Surface Bone Density (BS/TV), Number of Trabeculae (Tb.N) and Bone Connectivity (Conn), but not for Total Porosity (Po.tot) and Trabecular Thickness (Tb.Th). The histomorphometric analysis showed that the PG presented similar results to the BG regarding newly formed bone extension and to the BG and BFG regarding newly formed bone area. The porcine-derived graft presented superior microtomographic and histomorphometric results when compared to the two bovine bone substitutes.

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.

Functional and Cosmetic Outcome after Reconstruction of Isolated, Unilateral Orbital Floor Fractures (Blow-Out Fractures) with and without the Support of 3D-Printed Orbital Anatomical Models

The present study aimed to analyze if a preformed "hybrid" patient-specific orbital mesh provides a more accurate reconstruction of the orbital floor and a better functional outcome than a standardized, intraoperatively adapted titanium implant. Thirty patients who had undergone surgical reconstruction for isolated, unilateral orbital floor fractures between May 2016 and November 2018 were included in this study. Of these patients, 13 were treated conventionally by intraoperative adjustment of a standardized titanium mesh based on assessing the fracture's shape and extent. For the other 17 patients, an individual three-dimensional (3D) anatomical model of the orbit was fabricated with an in-house 3D-printer. This model was used as a template to create a so-called "hybrid" patient-specific titanium implant by preforming the titanium mesh before surgery. The functional and cosmetic outcome in terms of diplopia, enophthalmos, ocular motility, and sensory disturbance trended better when "hybrid" patient-specific titanium meshes were used but with statistically non-significant differences. The 3D-printed anatomical models mirroring the unaffected orbit did not delay the surgery's timepoint. Nonetheless, it significantly reduced the surgery duration compared to the traditional method (58.9 (SD: 20.1) min versus 94.8 (SD: 33.0) min, p-value = 0.003). This study shows that using 3D-printed anatomical models as a supporting tool allows precise and less time-consuming orbital reconstructions with clinical benefits.

Intraocular Migration of Porous Polyethylene Malar Implant Used for Treacher Collins Eyelid Reconstruction

Lower eyelid colobomas associated with Treacher Collins syndrome can be challenging to repair because of associated orbital and midfacial dysostosis. Alloplastic implants such as porous polyethylene have been advocated as readily available malar implants to help improve eyelid retraction. The authors report the first case of porous polyethylene implant insidious migration into the orbit with subsequent scleral penetration. A 14-year-old male with Treacher Collins syndrome, presented with a 3-week history of left eye pain, redness, and eyelid swelling unresponsive to topical treatment. He previously had bilateral lower lid coloboma repair with alloplastic implant placement and full-thickness skin grafts. On exam, he had left eye injection and chemosis, with left hypotropia and complete restrictive ophthalmoplegia. Imaging revealed displacement of implant into the orbit with adherence and impingement on the eye globe.

Quality of life after reconstruction of traumatic orbital floor defects using titanium mesh and medpore: A randomised controlled trial

AIM AND OBJECTIVES

The aim of this study was to analyse the outcomes of orbital floor reconstruction with two types of orbital implants and assess patients' quality of life.

MATERIAL AND METHODS

39 sequential patients with clinical and radiological evidence of orbital floor fracture, presenting diplopia, enophthalmos, paraesthesia or a post traumatic residual orbital deformity were included in this study and randomised for orbital floor reconstruction using porous polyethylene sheet (Biopore™) or preshaped titanium mesh on a 3D model. Their pre and postoperative quality of life were compared. Success rate was assessed and scored with a minimum of zero (none) and a maximum of ten (excellent) for improvement in the signs of diplopia, enophthalmos, hypoglobus, paraesthesia and aesthetics.

RESULTS

Both QOL scores and Success score was greater in cases which reconstruction of orbital floor was performed with preshaped titanium mesh as compared to those with Biopore™.

CONCLUSION

Preshaped titanium mesh shows better results than reconstruction with Biopore™. However a large sample size and a long term follow up is needed for generating the best evidence. Quality of life extensively improves after orbital floor reconstruction motivating the patients desire to live.

Surgical Decompression of the Orbit due to Frontal Bone and Roof of the Orbit Fractures - A Case Report

Trauma in the face region has a very varied etiology and can be associated with several important structures. Isolated fractures in the orbit region correspond to about 4 to 16% of all facial fractures and this incidence increases to 30 to 55% if we take into account fractures that expand to extraorbital regions. The present clinical report aims to describe the case of a male patient, 21-years-old, victim of a motorcycle accident with facial trauma and traumatic brain injury due to frontal collision. Clinical and imaging examinations showed multiple fractures in the face with herniation of brain mass to the orbital region and consequent extrusion of the eyeball. Surgical procedures were performed to reduce and fix fractures and multidisciplinary treatment aimed at preserving vision and brain integrity. Thus, the surgical approach and the multidisciplinary treatment led to an excellent prognosis attested by the one-year postoperative period.

Custom-Made Zirconium Dioxide Implants for Craniofacial Bone Reconstruction

Reconstruction of the facial skeleton is challenging for surgeons because of difficulties in proper shape restoration and maintenance of the proper long-term effect. ZrO₂ implant application can be a solution with many advantages (e.g., osseointegration, stability, and radio-opaqueness) and lacks the disadvantages of other biomaterials (e.g., metalosis, radiotransparency, and no osseointegration) or autologous bone (e.g., morbidity, resorption, and low accuracy). We aimed to evaluate the possibility of using ZrO₂ implants as a new application of this material for craniofacial bone defect reconstruction. First, osteoblast (skeleton-related cell) cytotoxicity and genotoxicity were determined in vitro by comparing ZrO₂ implants and alumina particle air-abraded ZrO₂ implants to the following: 1. a titanium alloy (standard material); 2. ultrahigh-molecular-weight polyethylene (a modern material used in orbital surgery); 3. a negative control (minimally cytotoxic or genotoxic agent action); 4. a positive control (maximally cytotoxic or genotoxic agent action). Next, 14 custom in vivo clinical ZrO₂ implants were manufactured for post-traumatologic periorbital region reconstruction. The soft tissue position improvement in photogrammetry was recorded, and clinical follow-up was conducted at least 6 years postoperatively. All the investigated materials revealed no cytotoxicity. Alumina particle air-abraded ZrO2 implants showed genotoxicity compared to those without subjection to air abrasion ZrO₂, which were not genotoxic. The 6-month and 6- to 8-year clinical results were aesthetic and stable. Skeleton reconstructions using osseointegrated, radio-opaque, personalized implants comprising ZrO₂ material are the next option for craniofacial surgery.

A prospective study of resolution of post-traumatic orbital complications using PRECLUDE® MVP: A randomized controlled trial

Orbital fractures alone represent 10% up to 25% of all facial fractures, but when they are associated with other fractures of the middle-third of the face, their incidence can increase up to 55%. This study aimed to identify whether the size of the orbital defect based on the classification by Jaquiéry et al. influenced the resolution of post-traumatic complications after orbital wall reconstruction using PRECLUDE®MVP alone or in combination with a titanium mesh or autogenous bone graft. Thirty-five orbits were categorized into four groups on the basis of the size of the defect and the operative techniques: group 1 contained 16 Jaquiéry class I orbits treated only with PRECLUDE®MVP; group 2 included eight class II orbits treated with PRECLUDE®MVP along with autogenous bone graft harvested from the calvaria or a titanium mesh; group 3 included five class III orbits and group 4 included six class IV orbits that were treated the same way as those in group 2. Spearman correlation showed that the use PRECLUDE®MVP didn't improve the post traumatic complications for big orbital defects due to the three-dimensional anatomical changes that occurred by neurologic lesions and lipolysis of the orbital contents.

Review of Orbital Fractures in an Urban Level I Trauma Center

Objective

To perform a comprehensive review and analysis of surgically treated orbital fractures.

Study Design

Retrospective cohort chart review study for surgically treated orbital fractures during 5 years.

Results

A total of 173 patients (average age 41.6 years) were diagnosed with orbital fractures. Most were male with a ratio of 3.3:1. Most fractures were caused by assault (39.3%); 22.5% of the cases were bilateral. The left orbit (40.5%) was fractured more than the right. The orbital floor (97.1%) was the most common anatomic location and the maxilla (65.3%) was the most commonly involved bone. The average time from trauma to surgical intervention was 8.7 ± 14.6 days and the average time from surgical intervention to discharge was 5.1 ± 9.0 days. The transconjunctival incision (63%) was the most commonly used incision, and nonresorbable implant (92.7%) was the most commonly used implant. Finally, the length of stay for the repair of a simple orbital fracture was less than for complex orbital fracture (1.5 days and 5.9 days, respectively).

Conclusion

Understanding the patterns and mechanisms of injury associated with orbital fractures can assist in developing standardized treatment protocols across all surgical specialties. This would ultimately allow for a uniform high quality of surgical care for patients with maxillofacial fractures.

Orbital wall restoring surgery with resorbable mesh plate

BACKGROUND

Orbital resorbable mesh plates are adequate to use for isolated floor and medial wall fractures with an intact bony buttress, but are not recommended to use for large orbital wall fractures that need load bearing support. The author previously reported an orbital wall restoring surgery that restored the orbital floor to its prior position through the transnasal approach and maintained temporary extraorbital support with a balloon in the maxillary sinus. Extraorbital support could reduce the load applied on the orbital implants in orbital wall restoring surgery and the use of resorbable implants was considered appropriate for the author's orbital wall restoring technique.

METHODS

A retrospective review was conducted of 31 patients with pure unilateral orbital floor fractures between May 2014 and May 2018. The patients underwent transnasal restoration of the orbital floor through insertion of a resorbable mesh plate and maintenance of temporary balloon support. The surgical results were evaluated by the Hertel scale and a comparison of preoperative and postoperative orbital volume ratio (OVR) values.

RESULTS

The OVR decreased significantly, by an average of 6.01% (p< 0.05) and the preoperative and postoperative Hertel scale measurements decreased by an average of 0.34 mm with statistical significance (p< 0.05). No complications such as buckling or sagging of the implant occurred among the 31 patients.

CONCLUSION

The use of resorbable mesh plate in orbital floor restoration surgery is an effective and safe technique that can reduce implant deformation or complications deriving from the residual permanent implant.

Orbital Floor Reconstruction: A Comparison of Outcomes between Absorbable and Permanent Implant Systems

There are distinct advantages and disadvantages between bioresorbable and permanent implants in orbital floor reconstruction. Our aim was to compare the outcomes and complications of resorbable implants and permanent implants in orbital floor fracture repair. A retrospective chart review was performed on all patients who underwent orbital floor fracture repair at a rural, tertiary care center from 2011 through 2016. Main outcome measures included improvement in diplopia, ocular motility, enophthalmos, hypoglobus, and infraorbital nerve sensation. A total of 87 patients underwent orbital floor reconstruction. After exclusion criteria were applied, 22 patients were included in the absorbable implant cohort, and 20 patients in the nonabsorbable implant cohort. All absorbable implants were composed of poly L-lactide/poly glycolide/poly D-lactide (PLL/PG/PDL), and nonabsorbable implants included both titanium/porous polyethylene (Ti/PPE) composite and titanium (Ti) mesh. Mean fracture surface area was 2.1 cm ² (standard deviation [SD]: ± 0.9 cm ² , range: 0.4-3.6 cm ² ) for the absorbable implant group and 2.3 cm ² (SD: ± 1.1 cm ² , range: 0.6-4.4 cm ² ) for the nonabsorbable implant group ( p  = 0.58). There were no significant differences in diplopia, ocular motility, enophthalmos, hypoglobus, and infraorbital nerve sensation between absorbable and nonabsorbable implant groups. The mean follow-up time for absorbable and nonabsorbable implant groups was 622 (SD ± 313) and 578 (SD ± 151) days respectively ( p  = 0.57). For moderate-size orbital floor fracture repairs, there is no difference in outcomes between absorbable implants consisting of PLL/PG/PDL and nonabsorbable implants consisting of Ti mesh or Ti/PPE combination.

Use of Acellular Allogenic Dermal Matrix (MegaDerm) in Orbital Wall Reconstruction: A Comparison With Absorbable Mesh Plate and Porous Polyethylene

The selection of materials for orbital wall reconstruction has been a matter of debate. This study aimed to evaluate the effectiveness of an acellular allogenic dermal matrix (ADM) as an orbital wall reconstruction material and to compare the results of orbital wall reconstruction with the ADM to those of reconstruction with the more widely used absorbable mesh plate and porous polyethylene. We retrospectively reviewed the clinical charts and computed tomography images of 73 patients who underwent orbital reconstruction at 1 institution between March 2013 and February 2014. In the ADM group, the mean defect size of 29 patients was 2.89 cm. After orbital wall reconstruction with ADM, patients with preoperative enophthalmos (7 patients), limited range of eyeball movement (6 patients), and diplopia (12 patients) showed improvements. In the comparative study, the 3 groups showed no significant differences with respect to age distribution (P = 0.522), defect size (P = 0.455), and preoperative findings such as enophthalmos (P = 0.811), diplopia (P = 0.357), and limited range of eyeball movement (P = 0.795). All the preoperative symptoms improved in every group, and in the ADM group, no complication was observed during the postoperative follow-up. ADM is a biocompatible material that combines the flexibility and rigidity required to support the orbital soft tissue. Therefore, it could be an excellent alternative material for orbital wall reconstruction.

Late Complication of a Silicone Implant Thirty Years after Orbital Fracture Reconstruction

Alloplastic materials used for orbital fracture reconstruction can induce complications, such as infection, migration, extrusion, intraorbital hemorrhage, and residual diplopia. Silicone is one of the alloplastic materials that has been widely used for decades. The author reports a rare case of spontaneous extrusion of a silicone implant that was used for orbital fracture reconstruction 30 years earlier. A 50-year-old man was admitted to the emergency room for an exposed substance in the lower eyelid area of the left eye, which began as a palpable hard nodule a week earlier. The exposed material was considered to be implant used for previous surgery. Under general anesthesia, the implant and parts of the fibrous capsule tissue were removed. Several factors hinder the diagnosis of implant extrusions that occur a long period after the surgery. So, surgeons must be aware that complications with implants can still arise several decades following orbital fracture reconstruction, even without specific causes.

Orbital reconstruction with a partially absorbable mesh (monofilament polypropylene fibre and monofilament poliglecaprone-25): Our experience with 34 patients

Purpose

To evaluate the effectiveness and complications related to the use of a partially absorbable mesh for the reconstruction of orbital floor fractures.

This is a retrospective review of 34 consecutive patients who suffered orbital trauma from August 2007 to March 2013 treated with a partially absorbable mesh for orbital reconstruction. Data collected included gender, age, nationality, cause of injury, date of admission, date of surgery, date of discharge, type of fracture, signs and symptoms such as diplopia, enophthalmos, and sensory disturbance related to the infraorbital nerve, complications before and after surgery, and follow-ups at 1 week, 1 month, 6 months, and after 1 year.

Results

Since January 2007, 34 patients were treated in our department with orbital fractures: 28 males (82.4%) and 6 females (17.6%). The mean age was 31 years (minimum 14, maximum 45). The main causes of trauma were road traffic accidents (20 patients, 58.8%), followed by work-related accidents (9 patients, 26.5%), aggressions (3 patients, 8.8%), and sports (2 patients, 6%). Posttraumatic Diplopia was present in 20 patients (58.8%), and enophthalmos was in 9 (26.5%). The incidence of postoperative diplopia was present in 8 patients (23.5%), which decreased to 1 (2.9%) after one year. Paresthesia due to trauma was first noticed in 8 patients (20.6%) and completely disappeared after 12 months. Post surgical enophthalmos was noticed in 3 patients (7.5%). There was one case of migration of the mesh and one case of adherence in the lower lid. Both required surgery and resolved completely. Time from trauma to surgery was on average 5.5 days (min 0, max 27, SD 5.15), and the number of days before discharge was 3.5 days (min 1, max 16, SD 2.61).

Conclusions

This study describes the results of the first series of orbital floor reconstructions with a partially absorbable mesh (Monofilament polypropylene fibre and monofilament poliglecaprone-25) to date. Although there are a wide variety of materials for treatment, we believe it is a suitable option with an acceptable rate of complications.

Orbital fracture repair outcomes with preformed titanium mesh implants and comparison to porous polyethylene coated titanium sheets

BACKGROUND

Restoration of orbital volume after internal orbital fractures can prevent enophthalmos. A variety of allografts are commonly used including titanium mesh with and without porous polyethylene coating. Some controversy exists over the use of uncoated titanium mesh in the orbit. Newer products contoured to the three dimensional orbital anatomy aim to improve reestablishment of the complex orbital shape though studies of outcomes with their use are limited.

METHODS

A retrospective chart review was performed to evaluate surgical outcomes in all patients who underwent orbital fracture repair with DePuy/Synthes titanium MatrixMIDFACE prefabricated implants (PFTi) as compared with porous polyethylene/titanium hybrid implants (PPETi) including Stryker Medpor Titan, MTB, and BTB implants. Incidence of reoperation, diplopia, and movement restriction between PFTi and PPETi groups and the risk ratio of the above outcomes between implant types were compared.

RESULTS

A total of 464 orbital implants were reviewed. Patients were divided by implant type with 195 patients receiving a PFTi implant and 269 patients receiving PPETi implant. (PFTi) and 269 had placement of a porous polyethylene/titanium hybrid implant. Despite statistically significant increased probability of utilization in more complex and delayed fractures, the PFTi implant showed no significant difference in complication profile or reoperation rate compared to the more commonly used PPETi.

CONCLUSIONS

PFTi implants, designed to replicate the native orbital shape, have similar surgical outcomes and no difference in complication profile compared to standard porous polyethylene/titanium implants hybrid plates.

Medial Wall Orbital Reconstruction using Unsintered Hydroxyapatite Particles/Poly L-Lactide Composite Implants

Background

Poly-L-lactide materials combined with hydroxyapatite (u-HA /PLLA) have been developed to overcome the drawbacks of absorbable materials, such as radiolucency and comparably less implant strength. This study was designed to evaluate the usefulness of u-HA/PLLA material in the repair of orbital medial wall defects.

Methods

This study included 10 patients with pure medial wall blow-out fractures. The plain radiographs were taken preoperatively, immediately after, and 2 months after surgery. The computed tomography scans were performed preoperatively and 2 months after surgery. Patients were evaluated for ease of manipulation, implant immobility, rigidity and complications with radiologic studies.

Results

None of the patients had postoperative complications, such as infection or enophthalmos. The u-HA/PLLA implants had adequate rigidity, durability, and stable position on follow-up radiographic studies. On average, implants were thawed 3.4 times and required 14 minutes of handling time.

Conclusion

The u-HA/PLLA implants are safe and reliable for reconstruction of orbital medial wall in terms of rigidity, immobility, radiopacity, and cost-effectiveness. These thin yet rigid implants can be useful where wide periosteal dissection is difficult due to defect location or size. Since the u-HA/PLLA material is difficult to manipulate, these implants are not suitable for use in complex 3-dimensional defects.

Inaugural Survey on Practice Patterns of Orbital Floor Fractures for American Oral and Maxillofacial Surgeons

PURPOSE

In recent years, several studies have reported on practitioners' preferences for the treatment of orbital floor fractures, showing widely varying practice patterns. The purpose of the present study was to identify the practice patterns among oral and maxillofacial surgeons involved in the management of orbital floor fractures in the United States and compare them with the available published data.

MATERIALS AND METHODS

An anonymous survey was created and electronically mailed to surgeons. We also reviewed the published data on orbital floor fractures using a PubMed and MEDLINE search. The responses to the survey were analyzed using descriptive statistics.

RESULTS

The factors that had the greatest influence on the surgeon's decision to operate were a defect size > 2 cm2, enophthalmos, entrapment, and persistent diplopia. The most common surgical approach reported was a preseptal transconjunctival approach (32.0%), followed by the subciliary (27.9%) and postseptal transconjunctival (26.2%) approaches. The most commonly reported implant for orbital reconstruction was titanium (65.4%), followed by Medpor (43.7%) and composite Medpor and titanium (26.4%). The review of the published data showed a consensus among many of the operative indications mentioned, including a large defect size, enophthalmos, clinical entrapment, and persistent diplopia.

CONCLUSIONS

Oral and maxillofacial surgeons in the United States have a wide range of practice habits in the management of orbital floor fractures. Although the quality of the available evidence is poor, it supports a consistent approach to the management of orbital floor fractures in terms of the indications and surgical approach. The choice of reconstructive material and timing of repair remain more controversial. A clear need exists for improvement in the available data to help guide and set standards of care for the specialties managing orbital floor fractures.

Reconstruction of Orbital Floor Fractures with Porous Polyethylene Implants: A Prospective Study

PURPOSE

The main aim of our study was to assess and evaluate the efficacy, long standing outcome and infection of porous polyethylene implants in treatment of orbital floor fractures.

PATIENT AND METHODS

Twelve patients with fractures of orbital floor were included in the study. The cause of fracture was road traffic accident, self fall and cow hit respectively. They also complained of enophthalmos (n = 9), diplopia (n = 3), restricted eye movement (n = 2), impairment of infraorbital nerve (n = 3) and dystopia (n = 6). All the fractures were reconstructed with thin porous polyethylene sheets.

RESULTS

No implants were extruded and there were no signs of inflammatory reactions against porous polyethylene implant. In all nine patients with pre-op enophthalmos it was corrected post-operatively with p value = 0.000 and was statistically significant; diplopia in one patient was corrected; persistence of double vision was noted in two patients. Restricted eye movement was corrected in all patients, dystopia was corrected in four patients and in two patients have persisting dystopia. Paresthesia persisted in all three patients.

CONCLUSION

Our experience was that reconstruction of orbital floor fracture using porous polyethylene implant is reliable, safe and effective and may be used for reconstruction of the orbital floor fracture with no donor site morbidity.

Reconstruction of orbital floor blow-out fractures with autogenous iliac crest bone: a retrospective study including maxillofacial and ophthalmology perspectives

This is a 10-year retrospective study of patients with an isolated unilateral orbital floor fracture reconstructed with an autogenous iliac crest bone graft. The following inclusion criteria applied: isolated orbital floor fracture without involvement of the orbital rim or other craniofacial injuries, pre-/post-operative ophthalmological/orthoptic follow-up, pre-operative CT. Variables recorded were patient age and gender, aetiology of injury, time to surgery, follow-up period, surgical morbidity, diplopia pre- and post-operatively (Hess test), eyelid position, visual acuity, and the presence of en-/or exophthalmos (Hertel exophthalmometer). Twenty patients met the inclusion criteria. The mean age was 29 years. The mean follow up period was 26 months. No patient experienced significant donor site morbidity. There were no episodes of post-operative infection or graft extrusion. Three patients had diplopia in extremes of vision post-operatively, but no interference with activities of daily living. One patient had post-operative enophthalmos. Isolated orbital blow-out fractures may be safely and predictably reconstructed using autogenous iliac crest bone. The rate of complications in the group of patients studied was low. The value of pre- and post-operative ophthalmology consultation cannot be underestimated, and should be considered the standard of care in all patients with orbitozygomatic fractures, in particular those with blow-out fractures.

Comparison of Absorbable Mesh Plate versus Titanium-Dynamic Mesh Plate in Reconstruction of Blow-Out Fracture: An Analysis of Long-Term Outcomes

Background

A blow-out fracture is one of the most common facial injuries in midface trauma. Orbital wall reconstruction is extremely important because it can cause various functional and aesthetic sequelae. Although many materials are available, there are no uniformly accepted guidelines regarding material selection for orbital wall reconstruction.

Methods

From January 2007 to August 2012, a total of 78 patients with blow-out fractures were analyzed. 36 patients received absorbable mesh plates, and 42 patients received titanium-dynamic mesh plates. Both groups were retrospectively evaluated for therapeutic efficacy and safety according to the incidence of three different complications: enophthalmos, extraocular movement impairment, and diplopia.

Results

For all groups (inferior wall fracture group, medial wall fractrue group, and combined inferomedial wall fracture group), there were improvements in the incidence of each complication regardless of implant types. Moreover, a significant improvement of enophthalmos occurred for both types of implants in group 1 (inferior wall fracture group). However, we found no statistically significant differences of efficacy or complication rate in every groups between both implant types.

Conclusions

Both types of implants showed good results without significant differences in long-term follow up, even though we expected the higher recurrent enophthalmos rate in patients with absorbable plate. In conclusion, both types seem to be equally effective and safe for orbital wall reconstruction. In particular, both implant types significantly improve the incidence of enophthalmos in cases of inferior orbital wall fractures.

Blowout fracture in a 3-year-old

A 3-year-old patient was referred to the oral and maxillofacial department with a fracture of the orbital floor. Due to the lack of clinical symptoms, a conservative approach was chosen. After 3 weeks, an enophthalmos developed. The orbital floor reconstruction was successfully performed through a transconjunctival approach. This case highlights the rarity of pure blowout fractures in young children. The specific presentation and diagnostics of orbital floor fractures in children and the related surgical planning and intervention are discussed.

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.

Preformed vs intraoperative bending of titanium mesh for orbital reconstruction

OBJECTIVE

The most accurate orbital reconstructions result from an anatomic repair of the premorbid orbital architecture. Many different techniques and materials have been used; unfortunately, there is currently no optimal method. This study compares the use of preformed vs intraoperative bending of titanium mesh for orbital reconstruction in 2-wall orbital fractures.

STUDY DESIGN

Cadaver-based study.

SETTING

University hospital.

SUBJECTS AND METHODS

Preinjury computed tomography scans were obtained in 15 cadaveric heads (30 orbits). Stereolithographic (STL) models were fabricated for 5 of the specimens (10 orbits). Two wall fractures (lamina papyracea and floor) were then generated in all orbits. Surgical reconstruction was performed in all orbits using 1 of 3 techniques (10 orbits each): (1) patient-specific implant molded from the preinjury STL model, (2) titanium mesh sheet bent freehand, and (3) preformed titanium mesh. Each technique was evaluated for orbital volume correction, contour accuracy, ease of use, and cost.

RESULTS

No difference in volume restoration was found between the 3 techniques. Patient-specific implants had the greatest contour accuracy, poor ease of use, and highest cost. Freehand bending implants had the poorest contour accuracy, acceptable ease of use, and lowest cost. Preformed mesh implants had intermediate contour accuracy, excellent ease of use, and low cost.

CONCLUSION

All 3 techniques provide equivalent orbital volume correction. However, preformed mesh implants have many advantages based on contour accuracy, ease of use, and relative cost.

Management of midface maxillofacial trauma

The management of midface trauma continues to challenge maxillofacial surgeons. The complex local anatomy and functional and cosmetic importance of the region make precise surgical correction and reconstruction essential to success.

Composite materials based on poly(trimethylene carbonate) and β-tricalcium phosphate for orbital floor and wall reconstruction

Poly(trimethylene carbonate) and β-tricalcium phosphate (PTMC/β-TCP) composite materials were prepared by coprecipitation and compression molding. The effect of different amounts of the ceramic component (15 and 30 vol %) on the properties was investigated. The effect of lamination with minimal amounts of poly(D,L-lactide) (PDLLA) was assessed as well. It was hypothesized that these composites would be suitable for orbital floor reconstruction, as the polymer component resorbs enzymatically without the formation of acidic compounds, while the ceramic component could induce bone formation. To asses their suitability as load bearing devices, the flexural properties of the prepared (laminated) composites were determined in three point bending experiments and compared with those of currently used reconstruction devices. The flexural modulus of PTMC composites increased from 6-17 MPa when introducing 30 vol % β-TCP. A laminate of this composite with PDLLA (with respective layer thicknesses of 0.8 and 0.2 mm) had a flexural modulus of 64 MPa. When evaluated in a mechanical engineering model of the orbital floor the (laminated) composites materials showed similar behavior compared to the currently used materials. The results suggest that from a mechanical point of view these (laminated) composite sheets should be well suited for use in orbital floor reconstruction.

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.