Biodegradable Fixation System Research Articles

Epoxidized Soybean Oleic Acid/Oligomeric Poly(lactic acid)-Grafted Nano-Hydroxyapatite and Its Role as a Filler in Poly(L-lactide) for Potential Bone Fixation Application.

One of the most effective strategies for modifying the surface properties of nano-fillers and enhancing their composite characteristics is through polymer grafting. In this study, a coprecipitation method was employed to modify hydroxyapatite (HAP) with epoxidized soybean oleic acid (ESOA), resulting in ESOA-HAP. Subsequently, oligomeric poly(lactic acid) (OPLA) was grafted onto the surface of ESOA-HAP, yielding OPLA-ESOA-HAP. HAP, ESOA-HAP, and OPLA-ESOA-HAP were comprehensively characterized. The results demonstrate the progressive grafting of ESOA and OPLA onto the surface of HAP, resulting in enhanced hydrophobicity and improved dispersity in organic solvent for OPLA-ESOA-HAP compared to HAP. The vitality and adhesion of Wistar rat mesenchymal stem cells (MSCs) were assessed using HAP and modified HAP materials. Following culture with MSCs for 72 h, the OPLA-ESOA-HAP showed an inhibition rate lower than 23.0% at a relatively high concentration (1.0 mg/mL), which is three times lower compared to HAP under similar condition. The cell number for OPLA-ESOA-HAP was 4.5 times higher compared to HAP, indicating its superior biocompatibility. Furthermore, the mechanical properties of the OPLA-ESOA-HAP/PLLA composite almost remained unaltered ever after undergoing two stages of thermal processing involving melt extrusion and inject molding. The increase in the biocompatibility and relatively high mechanical properties render OPLA-ESOA-HAP/PLLA a potential material for the biodegradable fixation system.

The use of bioabsorbable poly-L-lactide acid miniplate and screw (FIXSORB®-MX ) for bone fixation in mandibular fracture: cases reports

Objective: This report aims to elucidate the degree of degradation of bioabsorbable poly-L-lactide acid (PLLA) devices and the influence of these materials on the surrounding tissues in the human body.Methods: Two patients with fractured mandibles underwent treatment using a biodegradable fixation system. In the first case, the plates and screws were removed along with extraction of an impacted wisdom tooth at 6 months after surgery, and in the second case, the same procedure was performed 12 months after surgery. Changes in the physical properties of the materials and histologic alterations in the periosteum and bone associated with the bioabsorbable plates were assessed.Results: The materials demonstrated adequate degradation in the human body, and skeletal stability proved sufficient for the duration of mandibular bone healing without complications after surgery.Conclusion: On the basis these findings, it can be concluded that PLLA implants are useful for the fixation of human mandibular fractures.

Comparison of the long-term clinical performance of a biodegradable and a titanium fixation system in maxillofacial surgery: A multicenter randomized controlled trial.

BackgroundBiodegradable fixation systems could reduce or eliminate problems associated with titanium removal of implants in a second operation.AimThe aim of this study was to compare the long-term (i.e. >5 years postoperatively) clinical performance of a titanium and a biodegradable system in oral and maxillofacial surgery.Materials and methodsThe present multicenter Randomized Controlled Trial (RCT) was performed in four hospitals in the Netherlands. Patients treated with a bilateral sagittal split osteotomy (BSSO) and/or a Le Fort-I osteotomy, and those treated for fractures of the mandible, maxilla, or zygoma were included from December 2006 to July 2009. The patients were randomly assigned to either a titanium (KLS Martin) or a biodegradable group (Inion CPS).ResultsAfter >5 years postoperatively, plate removal was performed in 22 of the 134 (16.4%) patients treated with titanium and in 23 of the 87 (26.4%) patients treated with the biodegradable system (P = 0.036, hazard ratio (HR) biodegradable (95% CI) = 2.0 (1.05–3.8), HR titanium = 1). Occlusion, VAS pain scores, and MFIQ showed good and (almost) pain free mandibular function in both groups.ConclusionIn conclusion, the performance of the Inion CPS biodegradable system was inferior compared to the KLS Martin titanium system regarding plate/screws removal in the abovementioned surgical procedures.Trial registrationhttp://controlled-trials.com ISRCTN44212338.

Biodegradable fixation systems in pediatric craniofacial surgery: 10-year experience with 324 patients

Over the past 15 years, resorbable materials have been successfully used for osteosynthesis, but their high cost prevents widespread application. However, the use of resorbable systems could be a method of choice, especially in treatment of children in the active growth period. Obviously, biodegradable materials not only are highly competitive with known metal constructs in terms of fixation rigidity, biocompatibility, and a low risk of infection but also have an undeniable advantage, such as gradual resorption allowing quick return of damaged bones to the physiological conditions of functioning. A special feature of bioresorbable systems is that they can be assembled using ultrasonic welding, which greatly facilitates the fixation process and also provides necessary rigidity, even in cases of joining very thin bones when reliable fixation with screws is impossible. Over the past 10 years, we have used biodegradable systems in 324 patients. In 244 of them, we used traditional (plate/screw) systems; in 80 cases, an ultrasonic welding system was chosen for osteosynthesis. In the present work, we discuss, based on clinical evidence, the advantages and disadvantages of both fixation systems for reconstructive craniofacial surgery in children.

Evaluation of Biodegradable Fixation System for Mandibular Angulus Fracture by Using Finite Element Method

Evaluation of Biodegradable Fixation System for Mandibular Angulus Fracture by Using Finite Element Method M. Ay, S. Hartomacioglub,∗, B. Bakircioglu, H.E. Yuzbasioglu and T. Kubat Department of Mechanical Engineering, Marmara University, 34722 Istanbul, Turkey Department of Mechanical Education, Marmara University, 34722, Istanbul, Turkey Department of Mechatronic, Selcuk University, 42600 Konya, Turkey Department of Prosthodontics, Istanbul Medipol University, 34083, Istanbul, Turkey

Management of pediatric mandibular fractures using bioresorbable plating system – Efficacy, stability, and clinical outcomes: Our experiences and literature review

AimsThe purpose of this study was to determine the efficacy and stability of the biodegradable fixation system for treatment of mandible fractures in pediatric patients by measuring the bite force. MethodsSixty pediatric patients with mandibular fractures (36 males, 24 females) were included in this study. The 2.5-mm resorbable plates were adapted along Champy's line of ideal osteosynthesis and secured with four 2.5mm diameter monocortical resorbable screws, 8mm in length. All patients were followed for 10 months. Clinical parameters, such as soft tissue infection, nonunion, malunion, implant exposure, malocclusion, nerve injury, and bite force for stability, were prospectively assessed. ResultsAdequate fixation and primary bone healing was achieved in 100% of the cases. Six minor complications (10%) were observed: 2 soft tissue infections (3%), 1 plate dehiscence (2%), 1 malocclusion (2%), and 2 paresthesia (3%). Conclusion2.5-mm resorbable plating system along Champy's line of ideal osteosynthesis is a good treatment modality for mandible fractures in pediatric patients.

Comparison of the long-term skeletal stability between a biodegradable and a titanium fixation system following BSSO advancement — A cohort study based on a multicenter randomised controlled trial

Biodegradable fixation systems could reduce or eliminate the problems associated with removal of titanium plates. A multicenter randomised controlled trial (RCT) was performed in the Netherlands from December 2006-July 2009, and originally 230 injured and orthognathic patients were included. The patients were randomly assigned to either a titanium control group (KLS Martin) or to a biodegradable test group (Inion CPS). The aim of the present study was to compare the long-term skeletal stability of advancement bilateral sagittal split osteotomies (BSSO) of a biodegradable system and a titanium system. Only patients from the original RCT who were at least 18 years old and who had a BSSO advancement osteotomy were included. Those who had simultaneous Le Fort I osteotomy or genioplasty were excluded. Analysis of skeletal stability was made by digital tracing of lateral cephalograms.Long-term skeletal stability in BSSO advancement did not differ significantly between patients treated with biodegradable plates and screws and those treated with titanium plates and screws. Given the comparable amount of relapse, the general use of Inion CPS in the treatment of BSSO advancement should not be discouraged. On the basis of other properties a total picture of the clinical use can be obtained; the short-term stability, the intraoperative switches, the number of plates removed and cost-effectiveness.Trial registration of original RCT: http://www.controlled-trials.com; ISRCTN 44212338.

Comparison and validation of finite element analysis with a servo-hydraulic testing unit for a biodegradable fixation system in a rabbit model

The aim of this study was the biomechanical validation of three-dimensional finite element analysis (FEA) with a servo-hydraulic testing unit (STU) for a resorbable fixation system (RFS) in a rabbit model. Bilateral mandibular vertical body osteotomies (BMVBO) were performed in 15 female New Zealand rabbits. The animals were divided into three groups. The STU and FEA tests were done immediately after surgery in group 1 (1day), at the first postoperative month in group 2, and at the third postoperative month in group 3. Both stress tests were carried out by applying vertical forces at the lower incisal edge, loading from 0N force and increasing this until breakage occurred at the bone. The maximum forces that the hemimandibles could stand and the amount of deformation were recorded and analysed with the FEA and STU tests. We found the STU and FEA test results to be similar and that they could be used interchangeably for groups 1 and 3. However, the FEA results differed most from the real STU values in group 2 because of callus formation that had not ossified at the osteotomy line.

Decision-making considerations in application of biodegradable fixation systems in maxillofacial surgery – A retrospective cohort study

In a recent RCT comparing biodegradable (Inion CPS) with titanium (KLS Martin) plates and screws for fixation of osteotomies or fractures, we found that in 21% of the cases the surgeon decided intra-operatively to switch from biodegradable to titanium.The aim of the current retrospective cohort study was to analyse the reasons for these switches in order to find predictor variables that may be helpful in the decision to use biodegradable devices or not. The surgeons' opinion about the biodegradable system, and if there was a learning curve in the application of the biodegradable system were also investigated.All variables were assessed during the original RCT by using a questionnaire that was completed by the OMF surgeon directly post-operatively. For the outcome variable “surgeons' opinion” a separate questionnaire was used.Regarding the predictor variables a mandibular fracture had a higher risk of switching compared to a BSSO. However, looking at the reasons for these switches no firm conclusions can be drawn. There was a subjective learning curve to acquire the application-skills for the biodegradable system. There were no changes in isolated Le-Fort-I osteotomies despite the fact that the biodegradable system seems more difficult to apply in the midface. Inadequate stability was the main reason for switching. This can be material-related, or related to inexperience with or lack of confidence in the system, or impatience of the surgeon.A learning curve and personal preferences probably play an important role in the decision to switch. We think that with more patience and more experience it should be possible to increase both user comfort and confidence in the biodegradable system of Inion CPS, which likely will decrease the number of intra-operative switches.

A Randomized Clinical Trial of Biodegradable and Titanium Fixation Systems in Maxillofacial Surgery

Biodegradable fixation systems could reduce or delete the problems associated with metallic systems, since removal is not necessary. The aim of this study was to establish the effectiveness and safety of biodegradable plates and screws as potential alternatives to metallic ones. This multi-center randomized controlled trial was conducted from December 2006 to July 2009. Included were patients who underwent mandibular and/or Le Fort I osteotomies and those with fractures of the mandible, maxilla, and zygoma. The patients were assigned to a titanium control group (KLS Martin) or to a biodegradable test group (Inion CPS). The primary outcome measure was ‘bone healing 8 weeks post-operatively’. The Intention-To-Treat (ITT) analysis of 113 patients in the titanium group and 117 patients in the biodegradable group yielded a significant difference (p < 0.001), primarily because in 25 patients (21%) who were randomized to the biodegradable group, the surgeon made the decision to switch to titanium intra-operatively. Despite this ‘inferior’ primary outcome result, biodegradable plates and screws could be safely used when it was possible to apply them. The benefits of using biodegradable systems (fewer plate removal operations) should be confirmed during a follow-up of minimally 5 years (Controlled-trials.com ISRCTN number 44212338).

Editorial Comment

The authors have presented the case for the use of internal fixation after osteotomies used in the soft tissue reconstruction of exstrophy. I hope the authors continue their evaluation of this technique compared with other standard techniques in reference to clinically important questions regarding body image, penile size, and orthopedic concerns. Without any data to support the use of fixation, we have not embraced internal fixation at our institution out of concerns regarding erosion of the fixation device or the fixation screws into the bladder neck and surrounding soft tissues. This paper will stimulate us to revisit this discussion with our orthopedic colleagues. Three-dimensional Anatomy of the Pelvic Bone in Bladder Exstrophy: Comparison Between Patients Managed With Osteotomy and Pubic Symphysis Internal Fixation Using Metal PlatesUrologyVol. 76Issue 4PreviewTo compare intrapelvic osseous dimensions in classic bladder exstrophy patients who underwent pelvic osteotomy and pubic symphysis internal fixation, using metal plates without osteotomy by defining intrapelvic angles and distances using three-dimensional computed tomography scan (3D-CT). Full-Text PDF ReplyUrologyVol. 76Issue 4PreviewCurrently, we have used internal fixation of the pubic arch as a crucial prerequisite for optimal pubic secure closure in our exstrophy patients. Initially, we evaluated the outcomes of pubic bone approximation and internal fixation using a miniature metal plate and screws.1 Although during our 5-year follow-up, only one case of metal plate dislocation was detected, the concerns of probable tissue reactions, metal corrosion, and the need for a second operation for plate removal prompted us to apply a biodegradable fixation system as an effective alternative to metal plates. Full-Text PDF

Poster 172: Two Cases of Mandibular Fractures Using Bioabsorbable Poly-L-Lactide Acid Miniplate and Screw for Bone Fixation

Statement of the Problem: Recently, the bioabosorbable poly-L-lactide acid (PLLA) is a new material in craniomaxillofacial surgery for use in fixing bone segments. The degree of degradation and the influence to surrounding tissue of this material is clear in vivo and in vitro, but not in human body. Materials and Methods: Two cases of a fracture of mandible underwent management with a biodegradable fixation system. In case 1, at 6months following surgery, the plates and screws were removed with extraction of wisdom tooth obtaining informed consent and case 2 had the same procedure at 12 months later. Method of Data Analysis: Those removed materials were investigated about the degree of degradation from the changings of physical properties and the histologic alterations to periosteum and bone associated with bioabsorbable plats was assessed. Results: On this time, these materials had good degradation in human body and skeletal stability was sufficient for the time needed for mandibular bone healing without complications after surgery. Conclusion: On the basis of results of this study, it can be concluded that PLLA implants are useful for fixation of human mandibular fractures.

Efficacy and Safety of Biodegradable Osteofixation Devices in Oral and Maxillofacial Surgery: a Systematic Review

The use of osteofixation devices should be evidence-based if uncomplicated bone healing is to be achieved. Numerous studies describe and claim the advantages of biodegradable over titanium devices as a bone fixation method. Here, we systematically review the available literature to determine the clinical efficacy and safety of biodegradable devices compared with titanium devices in oral and maxillofacial surgery. In addition, related general aspects of bone surgery are discussed. We conducted a highly sensitive search in the databases of MEDLINE (1966-2005), EMBASE (1989-2005), and CENTRAL (1800-2005) to identify eligible studies. Eligible studies were independently evaluated by two assessors using a quality assessment scale. The study selection procedure revealed four methodologically 'acceptable' articles. Owing to the different outcome measures used in the studies, it was impossible to perform a meta-analysis. Therefore, the major effects regarding the stability and morbidity of fracture fixation using titanium and biodegradable fixation systems were qualitatively described. Any firm conclusions regarding the fixation of traumatically fractured bone segments cannot be drawn, due to the lack of controlled clinical trials. Regarding the fixation of bone segments in orthognathic surgery, only a few controlled clinical studies are available. There does not appear to be a significant short-term difference between titanium and biodegradable fixation systems regarding stability and morbidity. However, definite conclusions, especially with respect to the long-term performance of biodegradable fixation devices used in maxillofacial surgery, cannot be drawn.

A retrospective evaluation of rigid fixation in orthognathic surgery using a biodegradable self-reinforced (70L:30DL) polyactide

Objective: This study was designed to evaluate clinical and radiological evidence of osteotomy site healing in orthognathic surgery after rigid fixation using a biodegradable plating system. Study design: A follow up of 30 patients who underwent orthognathic surgery using a biodegradable self-reinforced (70L:30DL) polylactide plating system was presented. The follow-up schedule for all patients consisted of regular appointments at 1–180 days after surgery. Clinical evaluation involved notation of any abnormal swelling, infection, discoloration, or discharge at the osteotomy sites. Stability was evaluated by manual palpation. For radiographic evaluation, panoramic radiographs were taken immediately after surgery, and again at 7–180 days. The radiographs were analyzed for any visual changes in osteotomy fragments, resorptive changes in osteotomy fragments, callus formation, and union of the osteotomy segments. Results: No clinical complications and no radiological changes in the osteotomy sites were observed. Regarding the clinical usefulness of the biodegradable fixation system, fixation at the time of operation was considered as excellent in all 30 cases. Conclusions: The conclusions of this study were that self-reinforced (70L:30DL) polylactide was considered to be comparable to other forms of rigid internal fixation for orthognathic surgery.