Self-reinforced biodegradable plates and screws for fixation of zygomatic fractures

Reliability of Ultrasound-Guided One-Point Fixation for Zygomaticomaxillary Complex Fractures

This study aimed to analyze the precision and postoperative stability of ultrasound guided 1-point fixation on the zygomaticomaxillary buttress for the treatment of zygomaticomaxillary complex (ZMC) fractures. The authors analyzed 24 consecutive patients who underwent ultrasound-guided 1-point fixation for ZMC fractures without separation of the fracture at the frontal process of the zygomatic bone. The authors used titanium plates in the first 6 cases, and biodegradable plates in the remaining 18 cases. The authors obtained computed tomography images preoperatively, and again the first day after surgery (T1) and 6 months after the surgery (T2). The authors calculated vertical change (VC) and horizontal change (HC) of the zygoma on computed tomography. Precision was evaluated with T1 images. Stability was evaluated from T1 to T2, and titanium and biodegradable plates were compared. From T1 images, the mean VC and HC was 0.22° (range, 1.60°-1.08°) and 0.33° (range, 1.86°-1.03°), respectively. From T1 to T2, the mean VC and HC was 0.08° and 0.28°, respectively. Comparing the types of plates, the mean HC in the biodegradable plate group was 0.39°, which was significantly greater than that in the titanium plate group (mean -0.10°). However, as the degree of change was relatively small, this did not pose any clinical problems. Our findings suggest that ultrasound-guided 1-point fixation on the zygomaticomaxillary buttress provides accurate reduction on ZMC fractures without the separation of the frontal process of the zygomatic bone fracture. Sufficient stability was obtained, even with the use of biodegradable plates.

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

AIMS

The 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.

METHODS

Sixty 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 2.5 mm diameter monocortical resorbable screws, 8 mm 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.

RESULTS

Adequate 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%).

CONCLUSION

2.5-mm resorbable plating system along Champy's line of ideal osteosynthesis is a good treatment modality for mandible fractures in pediatric patients.

To evaluate the efficacy of biodegradable plating system for fixation of maxillofacial fractures: A prospective study

Aims:

The present study was undertaken to evaluate the efficacy of biodegradable plating system for fixation of maxillofacial fractures and to study the morbidity associated with the use of biodegradable plates and screws.

Materials and Methods:

This prospective study consisted of 10 patients with maxillofacial fractures requiring open reduction and internal fixation. Fractures with infection, comminuted and pathological fractures were excluded. All were plated with biodegradable system (Inion CPS) using standard plating principles and observed for a total period of 24 weeks. Characteristics of the fractures, ease of use of bioresorbable plate/screw system and post operative complications were assessed.

Results:

Of total 10 patients, eight patients were of midface fracture and two pediatric patients with mandibular fracture, with nine male and one female. The mean age was 32.8 years. Out of 20 plates and 68 screws applied to the 10 fractures sites; there were three incidences of screw breakage with no other intraoperative difficulties. Paresthesia of the infraorbital nerve was present in two patients, and recovered completely in four weeks after surgery. Fracture reduction was considered to be satisfactory in all cases. One patient developed postsurgical infection and was managed with oral antibiotics and analgesics.

Conclusions:

Favorable healing can be observed through the use of biodegradable plates and screws to stabilize selected midface fractures in patients of all ages, as well as mandible fractures in early childhood, however further studies with more sample size are required.

Fixation of zygomatic and mandibular fractures with biodegradable plates

Context:

In this prospective study, 13 randomly selected patients underwent treatment for zygomatic–complex fractures (2 site fractures) and mandibular fractures using 1.5 / 2 / 2.5-mm INION CPS biodegradable plates and screws.

Aims:

To assess the fixation of zygomatic-complex and mandibular fractures with biodegradable copolymer osteosynthesis system.

Materials and Methods:

In randomly selected 13 patients, zygomatic-complex and mandibular fractures were plated using resorbable plates and screws using Champy's principle. All the cases were evaluated clinically and radiologically for the type of fracture, need for the intermaxillary fixation (IMF) and its duration, duration of surgery, fixation at operation, state of reduction at operation, state of bone union after operation, anatomic reduction, paresthesia, occlusal discrepancies, soft tissue infection, immediate and late inflammatory reactions related to biodegradation process, and any need for the removal of the plates.

Statistical Analysis Used:

Descriptives, Frequencies, and Chi-square test were used.

Results:

In our study, the age group range was 5 to 55 years. Road traffic accidents accounted for the majority of patients six, (46.2%). Postoperative occlusal discrepancies were found in seven patients as mild to moderate, which resolved with IMF for 1-8 weeks. There were minimal complications seen and only as soft tissue infection.

Conclusions:

Use of biodegradable osteosynthesis system is a reliable alternative method for the fixation of zygomatic-complex and mandibular fractures. The biodegradable system still needs to be refined in material quality and handling to match the stability achieved with metal system. Biodegradable plates and screws is an ideal system for pediatric fractures with favorable outcome.

Experimental evaluation of relapse-risks in operated zygoma fractures

OBJECTIVES

Prevention of relapse, or postoperative dislocation, of the fixed zygoma is necessary to achieve optimal results in the treatment of zygoma fractures. Assuming that the occurrence of intensified stresses on mastication at the screw-bone interface (SBI) constitutes the essential cause of the relapse, we evaluated the stresses for three different fixation methods-fixation at the frontal process (FP), inferior orbital rim (IOR), and zygomatico-maxillary buttress (ZMB).

METHODS

We used 10 computer-aided design (CAD) models simulating zygoma fractures in the experiment. For each CAD model, we fixed the fractured zygoma with four screws and one mini-plate at the FP, IOR, or ZMB. After applying a 5.5kg force simulating mastication, we calculated the intensity and distribution patterns of the stresses occurring at the SBIs of the fixation screws using the finite element method. Thereby, we evaluated dynamic stability of the fixed zygoma for each of the three fixation methods.

RESULTS

Greater stresses occur at the SBIs with IOR fixation than at those with FP and ZMB fixation. Although the stresses occurring at the SBIs on mastication demonstrated evenly distributed patterns with the FP and ZMB fixation, the stresses demonstrated concentration on one screw with the IOR fixation.

CONCLUSIONS

The fixed zygoma is more likely to cause relapse with the IOR fixation than with the FP or ZMB fixation. Hence, in performing zygoma fixation at the IOR, care should be taken to minimize the likelihood of postoperative relapse that is caused by skewed distribution of the stresses on the fixation screws.

MOC-PSSM CME article: Zygomatic fractures

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the common signs, symptoms, and treatment options for zygomatic fractures. 2. Answer basic questions on therapy for zygomatic fractures.

SUMMARY

This maintenance of certification article on zygomatic fractures attempts to review the current approaches to the treatment of these fractures. Although the article does not deal with extended approaches to treatment, it does in a general sense present the preoperative, intraoperative, and postoperative thinking for the plastic surgeon approaching these patients in general practice. A further in-depth review can be obtained through the references at the end of the article.