Technique for applying 2 miniplates for treatment of mandibular angle fractures

Medial Epicanthoplasty With the Classic and Modified Skin Redraping Method: A Retrospective Case Control Study

ABSTRACT

The skin redraping method for medial epicanthoplasty is characterized by some shortcomings which warrants modification. In this study, clinical data of 193 patients who underwent medial epichanthoplasty by the modified skin redraping technique or the classic skin redraping technique were reviewed retrospectively. The patients underwent operation between May 2018 and June 2020 and were followed up for not less than 6 months. Interepicanthal distance , interpupillary distance, patient satisfaction, and postoperative complications were evaluated. In terms of interepicanthal distance/interpupillary distance ratio (P > 0.05) and satisfaction score (P = 0.759), the modified skin redraping technique and the classic skin redraping technique were similar. In the classic skin redraping group, there were 3 cases of visible scarring in the lower eyelid, corresponding to significantly more cases than in the modified skin redraping group (n = 0, P < 0.001). There were more out-fold cases in the modified skin redraping group (76/90) than in the classic skin redraping group (17/88) (P < 0.001). Utilizing the modified skin redraping medial epicanthoplasty can prevent medial hooding of the upper eyelid, reduce the probability of visible scarring, and produce more out-fold with concurrent double eyelidplasty compared with classic skin redraping epicanthoplasty.Level of evidence: IV.

Treatment of Mandibular Angle Fractures with Single Three-Dimensional Locking Miniplates without Maxillomandibular Fixation: How Much Fixation Is Required?

The aim of this simple nonrandomized and observational study was to evaluate the efficacy of single three-dimensional (3D) plate for the treatment of mandibular angle fractures without maxillomandibular fixation. A total of 30 patients with noncomminuted fractures of mandibular angle requiring open reduction and internal fixation were included in the study. All the patients were treated by open reduction and internal fixation using single 3D titanium locking miniplate placed with the help of transbuccal trocar or Synthes 90-degree hand piece and screw driver. 3D locking titanium miniplates used in our study was four-holed, box-shaped plate, and screws with 2 mm diameter and 8 mm length. The following clinical parameters were assessed for each patient at each follow-up visit: pain (visual analog scale: 0-5), swelling (visual analog scale: 0-5), mouth opening, infection, paresthesia, hardware failure (plate fracture), occlusal discrepancies, and mobility between fracture fragments. A significant decrease in pain level was seen during the follow-up visits. No statistically significant changes were seen in swelling, but mouth opening increased in the subsequent visits. Also better results were seen in terms of fracture stability and occlusion in the postoperative period. Two cases of infection and two cases of hardware failure were noted in sixth postoperative week. 3D plating system is an easy to use alternative to conventional miniplates to treat mandibular angle fractures that uses lesser foreign material, thus reducing the operative time and overall cost of the treatment. Better fracture stability and occlusion was also achieved using the 3D plating system.

Biomechanical comparison of four mandibular angle fracture fixation techniques

The aim of this study was to make a comparison of the biomechanical behavior of four different internal fixation systems for mandibular angle fractures. A total of 40 polyurethane mandible replicas were employed with different fixation methods: group 1SP, one 2.0-mm four-hole miniplate; group 2PPL, two 2.0-mm four-hole parallel miniplates; group 3DP, one 3D 2.0-mm four-hole miniplate; and group 3DPP, one 3D 2.0-mm eight-hole miniplate. Each group was subjected to incisal or homolateral molar region loading. The load resistance values were measured at load application causing tip displacement of 1, 3, and 5 mm, and at the time at which the system achieves its maximum strength (MS). Means and standard deviations were compared among groups using analysis of variance and the Tukey test. Group 2PPL showed higher strength for all the displacements. For incisal loading, no statistically significant differences were found between groups 1SP, 3DP, and 3DPP. For molar loading, group 1SP and 3DPP showed statistically significant differences. For MS testing, group 1SP and 2PPL showed statistically significant differences in incisal loading; group 1SP and 3DP showed no statistically significant differences; and group 3DPP showed lower values of strength. Two parallel miniplates provide the most favorable mechanical behavior under the conditions tested.

Biomechanical comparison of different plating techniques in repair of mandibular angle fractures

OBJECTIVE

The purpose of this study was to evaluate the biomechanical behaviors of different miniplate fixation techniques for treatment of fractures of the mandibular angle.

STUDY DESIGN

Twenty sheep hemimandibles were used to evaluate 4 different plating techniques. The groups were fixated with Champy technique, biplanar plate placement, monoplanar plate placement, and 3-dimensional (3D) curved angle strut plate. A custom-made 3-point biomechanical test model was used for the samples. Each group was tested with compression forces by an Instron Lloyd LRX machine. The biomechanical behavior of the groups for the forces (N) that caused displacement of 1.75 mm were compared using the Instron software program and displacement graphics.

RESULTS

The variance analyses showed that biplanar plate placement had more favorable biomechanical behavior than Champy technique and monoplanar plate placement (P < .05). In addition, the 3D curved angle strut plate technique had more favorable biomechanical behavior than the Champy technique (P < .05) but was not significantly different from biplanar or monoplanar plate placement techniques (P > .05).

CONCLUSION

The study demonstrated that 3D strut plates or dual miniplate techniques had greater resistance to compression loads than the Champy technique. In addition, biplanar plate orientation may provide a more favorable biomechanical behavior than monoplanar plate placement.

Comparison of different fixation methods following sagittal split ramus osteotomies using three-dimensional finite elements analysis. Part 1: advancement surgery-posterior loading

The purpose of this study was to evaluate the mechanical behavior of different fixation methods used in bilateral sagittal split ramus osteotomy (BSSRO). Part 1 comprises of the results of the analysis for mandibular advancement, four different fixation configurations of six hole fragmentation mini plates with monocortical screws and lag screws and posterior loading conditions in the molar and premolar region. The finite element analysis method (FEA) appears suitable for simulating complex mechanical stress situations in the maxillofacial region. The mechanical behavior of selected lag screws with linear or triangular configuration and double parallel or single oblique six hole mini plates with monocortical screws were compared by FEA after 5 mm BSSRO advancement procedure. Four separate three-dimensional finite element models of the mandible were created to simulate the BSSRO and corresponding fixation methods. These models consisted of 122,717 elements and 25,048 nodes. The mechanical parameters of the materials studied were adopted from the literature or were based on manufacturer's information. 500 N posterior occlusal loads were simulated on the distal segments. The commercial finite element solver MSC Marc software was utilized to calculate the stress fields on both the segments and fixative appliances. It was concluded that the use of 2.0mm lag screws placed in a triangular configuration following the BSSRO advancement surgery provides sufficient stability with any rotational movement and less stress fields at the osteotomy site, when compared with the other rigid fixation methods used in the current study.

Descriptive terminology of the mandible

There is a considerable anomaly in the use of descriptive terms relating to the mandible. This ambiguity poses a potential risk of misinterpretation of patient's records and publications. Recommendations are made to improve clarity and avoid confusion.