An evaluation of the clinical application of three different biodegradable osteosynthesis materials for the fixation of zygomatic fractures

Fifteen-Year Review of the American Board of Plastic Surgery Maintenance of Certification Tracer Data: Clinical Practice Patterns and Evidence-Based Medicine in Zygomatico-Orbital Fractures

BACKGROUND

From 2005 to 2020, the American Board of Plastic Surgery collected data on 20 common plastic surgery operations as part of the Maintenance of Certification process. These data allow the authors to examine national trends in zygomatico-orbital fracture repair over a 15-year period.

METHODS

Tracer data for zygomatico-orbital fracture repair were reviewed in cohorts from 2005 to 2013 and 2014 to 2020. Results were categorized based on their presence in evidence-based medicine articles published during this period. Differences between years were assessed using the t test or chi-square test as appropriate.

RESULTS

Four hundred thirty patients were included as of March of 2020. Average age was 37 years (range, 6 to 85 years), and 76 percent were male. Operations took place on average 10 days from injury. There were significant decreases in the use of subciliary (31.9 percent versus 10.0 percent; p < 0.001), gingival buccal (84.3 percent versus 56.4 percent; p < 0.001), and lateral brow (45.2 percent versus 22.3 percent; p < 0.001) incisions, with an increase in lower lid external incisions (15.2 percent versus 30.9 percent; p < 0.001); 2.7 percent of patients had a complication requiring readmission and 4.5 percent required reoperation. The incidence of postoperative diplopia was 7.7 percent, and the infection rate was 1.7 percent.

CONCLUSIONS

This article reviews the American Board of Plastic Surgery tracer data for zygomatico-orbital fracture repair. The Maintenance of Certification tracer data provide a national database with longer follow-up and more specific information than comparable databases. Analysis of these data over time enables the authors to describe practice trends and gives surgeons the opportunity to compare their outcomes to national norms.

Bioabsorbable Osteofixation Materials for Maxillofacial Bone Surgery: A Review on Polymers and Magnesium-Based Materials

Clinical application of osteofixation materials is essential in performing maxillofacial surgeries requiring rigid fixation of bone such as trauma surgery, orthognathic surgery, and skeletal reconstruction. In addition to the use of titanium plates and screws, clinical applications and attempts using bioabsorbable materials for osteofixation surgery are increasing with demands to avoid secondary surgery for the removal of plates and screws. Synthetic polymeric plates and screws were developed, reaching satisfactory physical properties comparable to those made with titanium. Although these polymeric materials are actively used in clinical practice, there remain some limitations to be improved. Due to questionable physical strength and cumbersome molding procedures, interests in resorbable metal materials for osteofixation emerged. Magnesium (Mg) gained attention again in the last decade as a new metallic alternative, and numerous animal studies to evaluate the possibility of clinical application of Mg-based materials are being conducted. Thanks to these researches and studies, vascular application of Mg-based biomaterials was successful; however, further studies are required for the clinical application of Mg-based biomaterials for osteofixation, especially in the facial skeleton. The review provides an overview of bioabsorbable osteofixation materials in maxillofacial bone surgery from polymer to Mg.

Evaluation of one-point fixation for zygomaticomaxillary complex fractures using a three-dimensional photogrammetric analysis

BACKGROUND

The goal of treatment for zygomaticomaxillary (ZM) complex (ZMC) fractures is to achieve stability and restore aesthetic appearance through three-dimensional reduction and rigid fixation. The purpose of this study was to evaluate the stability and aesthetic appearance outcomes of one-point fixation using a three-dimensional photogrammetric analysis.

METHODS

From March 2014 to December 2014, 34 patients with ZMC fractures were treated by one-point fixation in the ZM buttress using unsintered hydroxyapatite (u-HA)/poly-L-lactide (PLLA) plates. Differences in soft tissue inter-malar height between the fractured side and unfractured sides were evaluated using photogrammetric analysis with a three-dimensional camera (Morphius®) at the preoperative and 1 week, 1 and 3 months after surgery. The differences in bony inter-malar height between the fractured and unfractured sides were evaluated using computer tomography at the pre-operative and 6 months after surgery. The paired t-test was used to compare differences in malar height.

RESULTS

Six months after surgery, 34 patients achieved satisfactory bony stability and symmetric malar appearances. Comparisons of differences in soft-tissue inter-malar height revealed statistically significant differences between the pre-operative period and 1 week and 1 month after surgery (p < .01). There was no statistically significant difference between 1 and 3 months after surgery. Comparison of differences in bony inter-malar height revealed a statistically significant difference between before and 6 months after surgery (p < .01).

CONCLUSIONS

When we conducted a three-dimensional photogrammetric analysis, although it has restricted surgical indications, one-point fixation of the ZM buttress using an u-HA / PLLA plate yielded reliable, satisfactory, and safe clinical results in patients with ZMC fractures.

CLINICAL QUESTION / LEVEL OF EVIDENCE

Therapeutic, III.

Are Biodegradable Osteosyntheses Still an Option for Midface Trauma? Longitudinal Evaluation of Three Different PLA-Based Materials

The aim was to evaluate three different biodegradable polylactic acid- (PLA-) based osteosynthesis materials (OM). These OM (BioSorb, LactoSorb, and Delta) were used in 64 patients of whom 55 (85.9%) had fractures of the zygoma, five (7.8%) in the LeFort II level, two of the frontal bone (3.1%), and two of the maxillary sinus wall (3.1%). In addition to routine follow-up (FU) at 3, 6, and 12 months (m) (T1, T2, and T3) all patients were finally evaluated at a mean FU after 14.1 m for minor (e.g., nerve disturbances, swelling, and pain) and major (e.g., infections and occlusal disturbances) complications. Out of all 64 patients 38 presented with complications; of these 28 were minor (43.8%) and 10 major (15.6%) resulting in an overall rate of 59.4%. Differences in minor complications regarding sensibility disturbance at T1 and T3 were statistically significant (P = 0.04). Differences between the OM were not statistically significant. Apart from sufficient mechanical stability for clinical use of all tested OM complications mostly involved pain and swelling probably mainly related to the initial bulk reaction attributable to the drop of pH value during the degradation process. This paper includes a review of the current aspects of biodegradable OM.

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.

Resorbable implants in maxillofacial surgery: a reality check

BACKGROUND

Stability is the main feature of fixation techniques in fracture management modalities, in vogue today. One of the most significant landmarks in the armamentarium of maxillofacial fracture management has been the introduction of rigid internal fixation (RIF). The biomaterials used in RIF have seen a gradual change from Stainless steel to titanium due to the evidence based advantages of the latter. However, the inherent problems with metallic implants led to the introduction of resorbable polymers in RIF.

MATERIALS AND METHOD

This article evaluates the efficacy of these polymers in fixation of bone segments as compared to titanium fixation implants in 40 patients of zygomatic complex fractures. The study compared the clinical efficacy, technique, cost and time factors in the use of these two biomaterials.

RESULTS

The results showed very little difference after the use of these two biomaterials in spite of the increased time, technique sensitivity and cost of the resorbable system.

CONCLUSION

The argument for use of the resorbable fixation implants as a better alternative to titanium in maxillofacial fracture management seems overstated considering the insignificant differences in the results obtained but significant differences in the time taken and economics of the two biomaterials. The resorbabale system should ideally be restricted for use in pediatric craniofacial surgery.

Biological effect of resorbable plates on normal osteoblasts and osteoblasts derived from Pfeiffer syndrome

Biodegradable fixation devices made of the polymers polylactide, polyglycolide and their copolymers are used routinely during maxillofacial, craniofacial, and orthopedic reconstructive surgical procedures, thanks to their property of biodegradation that avoid the need for implant removal. In particular, they are used in the treatment of craniosynostosis in pediatric patients affected by Pfeiffer syndrome, where the resorption time of 1 year or less does not interfere with the normal growth of the skull. To study the mechanism how polylactide-polyglycolide (PLPG) acid plates can induce osteoblast differentiation and proliferation in normal osteoblasts and in osteoblasts derived from a patient with Pfeiffer syndrome, the expression levels of bone-related genes were analyzed using real-time reverse transcription-polymerase chain reaction. Osteoblasts grown on the PLPG acid plates resulted in significant upregulation of mRNA expression of many genes related to osteodifferentiation during the treatment, indicating that polylactide, polyglycolide biopolymers enhance proliferation, differentiation, and deposition of matrix in osteoblasts. This study also revealed some differences in gene expression between normal osteoblasts and osteoblasts derived from patients with Pfeiffer syndrome, cultivated on PLPG acid plates.

Complications after zygoma fracture fixation: Is there a difference between biodegradable materials and how do they compare with titanium osteosynthesis?

OBJECTIVE

Biodegradable materials are particularly useful for the fixation of zygomatic fractures. Different systems are commercially available. The aim of this study was to compare the clinical outcome of zygomatic fracture fixation using 3 biodegradable systems and a titanium osteosynthesis system.

STUDY DESIGN

Patients with displaced fractures of the zygomatic bone presenting at our department from October 2001 to May 2003 were randomly allocated to 1 of 3 treatment groups for fracture fixation (study group A: LactoSorb: n = 18; study group B: BioSorb: n = 18; study group C: Delta: n = 18). Treatment outcome and complication rates were compared with a historic patient group with zygomatic fractures fixed with titanium osteosynthesis (control group D: n = 15).

RESULTS

A total of 64 patients (study groups A + B + C: n = 49; control group D: n = 15) were followed for at least 24 months (range: 24 to 44 months). Forty-nine patients in the biodegradable study groups (group A: n = 15; group B: n = 17; group C: n = 17) who had their fractures fixed with biodegradable plates and screws alone or in combination with titanium plates and screws were reviewed postoperatively. Uneventful healing occurred during the entire follow-up period in 39 (80%) out of 49 patients in the biodegradable groups (A + B + C) and in 12 (80%) out of 15 patients in group D. Ten patients in groups A + B + C developed postoperative complications (infection: n = 3; soft tissue dehiscence: n = 2; implant-related tissue reactions: n = 5), compared with 3 patients in group D (soft tissue dehiscence: n = 1; unspecific pain: n = 2) (P = .97). Complications occurred in 4 patients in group A and 3 patients each in groups B and C. Smokers developed significantly more postoperative complications than nonsmokers in groups A + B + C (P = .01).

CONCLUSION

There was no significant difference between biodegradable osteosynthesis materials or between biodegradable materials and titanium fixation with respect to fracture healing and postoperative complications. Postoperative complications were of a minor nature and resolved spontaneously or after local therapy. Smoking habits may play a significant role in the incidence of complications with biodegradable materials.