Stryker SMARTLock Hybrid Maxillomandibular Fixation System: Clinical Application, Complications, and Radiographic Findings

Trends in Maxillomandibular Fixation Technique at a Single Academic Institution

Study Design

Retrospective chart review.

Objective

Restoration of premorbid occlusion is a key goal in the treatment of mandibular fractures. Placement of the patient in maxillomandibular fixation (MMF) is performed during mandibular fracture repair to help establish occlusion. A number of techniques are available to achieve MMF. We sought to examine trends in MMF technique at our institution.

Methods

A retrospective chart review was conducted to evaluate patients who underwent surgical treatment of mandibular fractures between January 1, 2011 and March 31, 2021. Data including fracture characteristics, mechanism of injury, patient demographics, complication rates, and MMF technique utilized were collected.

Results

One hundred sixty-three patients underwent MMF (132 males). The most common etiology of fracture was assault (34%). There was an increasing preference for rapid MMF techniques over time, as opposed to standard Erich arch bars. No significant difference in obtaining adequate fracture reduction as determined by postoperative imaging or complications were noted between those who underwent MMF with newer rapid techniques vs traditional MMF techniques.

Conclusions

Our institution has demonstrated changing trends in the technique utilized for establishing occlusion intraoperatively, more recently favoring rapid MMF techniques, with similar rates of complications and ability to adequately reduce fractures.

Real-time Reconstruction of Comminuted Mandibular Fractures Using 3D Printing

Background

Comminuted fractures of the jaws are complex injuries requiring special attention. In the past, treatment included closed reduction using maxillomandibular fixation. With advancements in technology and fixation systems, open reduction became a prevalent option. These fractures are difficult to reconstruct during the primary treatment phase, thus resulting in higher complication rates. The introduction of three-dimensional (3D) planning and printing brought about superior outcomes, yet these focus on secondary reconstruction due to the need for outsourcing planning and titanium printing.

Methods

In this report, we describe real-time in-house 3D planning and printing using computer-assisted design software and a 3D-fused deposition printer for virtual reduction of the comminuted fractures and printing of the reconstructed mandible.

Results

Following virtual 3D reduction, the newly created mandibles were 3D printed. The model was then used to preband a reconstruction plate, which in turn was used as a template during surgery for reducing the segments. The process of virtual reduction and printing should take a couple of hours at most. The results of five cases showed good alignment and proper function.

Conclusion

Three-dimensional technology can be applied in the everyday primary care treatment protocol of comminuted fractures as an in-house tool which greatly improves both functional and aesthetic outcomes.

The use of clear aligners in orthognathic surgeries: a case series

Pre- and postoperative fixed orthodontic appliances are the customary and standard practice for patients with treatment planned for undergoing orthognathic surgery. Traditionally, most patients undergoing orthognathic surgeries are in their late teens. Although these patients still compose the greatest pool of the orthognathic surgery population, many patients seek orthognathic surgery later in life. This older patient population often has different concerns and goals than the younger patient population. One of these concerns is often the aesthetic appearance of fixed appliances and the time required to wear these appliances pre- and postoperatively. Today, removable orthodontic appliances consisting of a series of clear aligners have gained immense popularity due to their aesthetic appeal over traditional braces. Additional benefits of removable orthodontic appliances include improved oral hygiene leading to a decreased risk of gingivitis. Whereas clear aligner systems are commonly used in the nonsurgical orthodontic population, there has been limited use of Invisalign in the orthognathic surgery population. In this article, we present a case series of 5 patients who successfully underwent orthognathic surgery using clear aligners for pre- and postoperative orthodontic treatment.

Comparison of Clinical Efficacy of Screw-retained Arch Bar vs Conventional Erich's Arch Bar in Maxillomandibular Fixation: A Randomized Clinical Trial

AIM

This study aimed to compare the clinical outcomes of a conventional Erich's arch bar vs a modified screw-retained arch bar in maxillomandibular fixation of mandibular fracture.

MATERIALS AND METHODS

This parallel-arm randomized control trial included patients from the outpatient clinic with single favorable mandibular fractures that are indicated for closed reduction. They were subjected to maxillomandibular fixation using conventional Erich's arch bars in the control group and modified screw-retained arch bars in the study group. The outcome measures included operating time, glove perforations, postoperative pain, oral hygiene, fixation stability, occlusion, and mucosal coverage.

RESULTS

A total of 20 patients (12 males and 8 females) with a 1:1 allocation ratio were included. There was a significant statistical difference regarding operation time and number of glove perforations in favor of group B as p < 0.001, p = 0.007, respectively. There was a significant statistical difference regarding pain after 1 day (p < 0.001), 1 week (p < 0.001) in favor of group B, and at 4 weeks (p = 0.015), and 6 weeks (p = 0.002) in favor of group A. Regarding oral hygiene at 1 week (p = 0.021) and at 6 weeks (p < 0.001), there was a significant statistical difference in favor of group B. Regarding mucosal coverage at 6 weeks, there was a significant statistical difference in favor of group A (p = 0.005).

CONCLUSION

The modified screw-retained arch bar can be considered an alternative to conventional arch bar as it provided less application time and better operator safety. It also showed better patient satisfaction regarding pain and oral hygiene.

CLINICAL SIGNIFICANCE

Maxillomandibular fixation with the conventional technique was modified to screw-retained arch bar which is less time-consuming and provides better patient and operator satisfaction. How to cite this article: Elhadidi MH, Awad S, Elsheikh HAE, et al. Comparison of Clinical Efficacy of Screw-retained Arch Bar vs Conventional Erich's Arch Bar in Maxillomandibular Fixation: A Randomized Clinical Trial. J Contemp Dent Pract 2023;24(12):928-935.

Comparison of Efficacy and Safety of Hybrid Arch Bar with Erich Arch Bar in the Management of Mandibular Fractures: A Randomized Clinical Trial

Study Design

A clinical randomized control trial.

Objective

To compare the efficacy and safety of Hybrid arch bar (HAB) with Erich arch bar (EAB) in fracture management of the mandible.

Methods

In this randomized clinical trial, 44 patients were divided into 2 groups:- Group 1, N = 23 (EAB group) and Group 2, N = 21 (HAB group). The primary outcome was time taken for the application of arch bar, while the inner and outer glove puncture, operator prick, oral hygiene, arch bar stability, complications of HAB, and cost comparison were secondary outcomes.

Results

The time taken for the application of arch bar in group 2 was significantly shorter than group 1 (55.66 ± 17.869 min vs 82.04 ± 12.197 min) and the frequency of outer glove puncture was also significantly lesser for group 2 (0 punctures vs 9 punctures). Better oral hygiene was found in group 2. EAB was cost-effective than HAB (Rs 700 ± 239.79 vs Rs 1742.50 ± 257.14). The stability of the arch bar was comparable in both groups. Group 2 had associated complications of root injury in 2 out of 252 screws placed and the screw head got covered by soft tissue in 137 out of 252 screws placed.

Conclusions

Thus, HAB was better than EAB with a shorter time of application, less risk of prick injury, and improved oral hygiene.Clinical trial registry name- clinical trials registry- India, URL-http://ctri.nic.in, registration number- CTRI/2020/06/025966.

Management of A Bad Split Complication: A Systematic Review

Introduction:

Bad split is one of the well-known intra-operative complications that occur during the bilateral sagittal split osteotomy (BSSO) procedure, which is a rehabilitation procedure for patients with mandibular deformities. The prevention of further post-surgery complications required sufficient management of bad split complications.

Objective:

This study aimed to analyze the management of bad split complications during a BSSO procedure.

Methods:

The literature review was conducted in the form of library research in the field of bad split complications' management by a BSSO based on the Preferred Reporting Items for Systematic Reviews (PRISMA). Related studies were found through using a manual search using Pubmed, ScienceDirect, Ebscohost, Scopus, Medline, Embase, and Web of Science, among other search engines. The inception of incorporation standards, the process of data extraction, and the determination of the risk of bias were carried out by the authors. The process of data screening was conducted by applying the inclusion and exclusion criteria.

Results:

This paper systematically reviewed seven related studies, four of which were case series and two of which were cross-sectional. The utilization of additional osteosynthetic plates was revealed throughout the extraction process as the most acquainted course of action to manage the bad split complications during the BSSO procedure.

Conclusion:

The osteosynthetic plate and miniplate application with bicortical or monocortical screws were exposed as the most used treatment for bad split complications.

Updates in Management of Craniomaxillofacial Gunshot Wounds and Reconstruction of the Mandible

This article includes updates in the management of mandibular trauma and reconstruction as they relate to maxillomandibular fixation screws, custom hardware, virtual surgical planning, and protocols for use of computer-aided surgery and navigation when managing composite defects from gunshot injuries to the face.

The use of screw retained hybrid arch bar for maxillomandibular fixation in the treatment of mandibular fractures: A comparative study

Introduction:

The use of screw-retained hybrid arch bars (HABs) is a relatively recent development in the treatment of mandibular fractures. The purpose of this study is to compare the clinical outcome between HAB and the conventional Erich arch bar (EAB) in the closed treatment of mandibular fractures.

Materials and Methods:

This study included 18 patients who were treated for mandibular fractures with maxillomandibular fixation (MMF), patients were randomly assigned into a control group (n = 10) in which EAB was used and study group (n = 8) in which HAB was used. The outcome variables were time required for application and removal, gingival inflammation scores, postoperative complications, and incidence of wire-stick injury or gloves perforation. The groups were compared using unpaired t-test, Mann–Whitney test, Chi-square test, or Fisher test. The differences were considered significant at P < 0.05.

Results:

The mean application time was significantly more in EAB than HAB (61.6 ± 11.4 vs. 41.6 ± 6 min, respectively). The mean time of removal for EAB was significantly less than HAB (11.1 ± 2 vs. 14.2 ± 3 min, respectively). There was nonsignificant difference in gingival inflammation between the groups. No major complications were recorded. Screw loosening and mucosal overgrowth were recorded in 12.5% and 31.2% of the screws, respectively, in HAB group. The incidence of gloves tear in EAB group was 70%.

Discussion:

HAB can be used as an alternative to EAB for MMF in patients with mandibular fracture, it requires less time for application and provides more safety for the surgeons.

A randomized prospective comparison of maxillomandibular fixation (MMF) techniques: "SMARTLock" hybrid MMF versus MMF screws

OBJECTIVE

The aim of this study was to assess the efficacy of the "SMARTLock" hybrid system and determine whether it results in fewer intraoperative and postoperative complications compared with placement of intermaxillary fixation (IMF) screws in trauma patients.

STUDY DESIGN

This prospective study, which was approved by the institutional review board, compared the results of MMF in mandibular fractures by using the Stryker "SMARTLock" hybrid system versus traditional IMF screws. Patients were recruited and assigned randomly to either group. The 2 groups were compared for placement time, intraoperative complications, loosening of hardware, postoperative complications, and time to device removal.

RESULTS

We enrolled 32 patients in the study, with 13 patients randomized to the group receiving hybrid MMF (HMMF) with the SMARTLock system and 19 to the group of patients receiving MMF with traditional IMF screws. The mean application time for HMMF was 25.92 minutes compared with 18.28 minutes for IMF screws. After removal, the HMMF was associated with gingival overgrowth and gingival edema.

CONCLUSIONS

This is the first study to compare HMMF with MMF with the use of IMF screws. Hybrid arch bars do require more manipulation for ideal placement compared with individually placed bone screws to achieve ideal MMF. Compared with IMF screws, the hybrid device was associated with gingival edema and overgrowth, but there was decreased incidence of loosening in the postoperative period.

Comparing Outcomes in Orthognathic Surgery Using Clear Aligners Versus Conventional Fixed Appliances

PURPOSE

Orthognathic surgery for dentofacial deformities is typically preceded and followed by orthodontic treatment. Traditionally, orthodontic hardware is secured to the dentition to allow dental movement and stabilization. Clear-aligner therapy (eg, Invisalign) provides an aesthetic alternative, consisting of a series of transparent trays. Its use has not been described in complex triple-jaw orthognathic surgery. The purpose of this study is to evaluate perioperative outcomes and 3-dimensionally quantify postoperative edema in Invisalign patients undergoing triple-jaw orthognathic procedures, comparing this to patients treated with conventional fixed appliances. The surgical approach to patients with clear-aligners is also outlined.

METHODS

The authors conducted a retrospective chart review and 3-dimensional morphometric study of Invisalign patients undergoing triple-jaw surgery (LeFort I osteotomy, bilateral sagittal split osteotomy, and genioplasty). An identical assessment of demographically matched patients treated with conventional fixed appliances was performed and compared with the Invisalign group.

RESULTS

Thirty-three patients, with a mean age of 19.99 years, were included: 13 with Invisalign and 20 with conventional fixed appliances. No significant difference was observed in operating time, concurrent extraction of teeth, fat grafting, duration of hospital stay, diet advancement, and use of narcotic analgesics between the 2 groups. Nine patients had sufficient 3-dimensional images for volumetric analysis (4 with Invisalign and 5 with conventional fixed appliances). Postoperative edema was not significantly different (P = 0.712) when comparing conventional fixed appliances (44.29 ± 23.16 cm) to Invisalign (37.36 ± 31.19 cm).

CONCLUSION

The present study demonstrates that complex multiple-jaw orthognathic procedures can be successfully performed in Invisalign patients. Perioperative and short-term clinical outcomes are not compromised.

A Clinical Comparison and Economic Evaluation of Erich Arch Bars, 4-Point Fixation, and Bone-Supported Arch Bars for Maxillomandibular Fixation

Importance

Erich arch bars, 4-point fixation, and bone-supported arch bars are currently used in maxillomandibular fixation, although to what extent they differ in terms of overall charges and clinical outcomes has yet to be reported.

Objective

To determine the association of Erich arch bars, 4-point fixation, and bone-supported arch bars in maxillomandibular fixation with hospital charges and clinical outcomes.

Design, Setting, and Participants

This historical cohort included 93 patients with mandible fracture who underwent maxillomandibular fixation from January 1, 2005, to June 30, 2015, at a tertiary care center. Statistical analysis was conducted from October 4, 2015, to September 8, 2017.

Main Outcomes and Measures

Charge analysis from an institutional perspective, operative time, necessity for a secondary procedure, and postoperative complications.

Results

Of the 93 patients in the study (18 women and 75 men; median age, 28.0 years [interquartile range, 23.0-40.0 years]), 27 (29%) received Erich arch bars, 51 (55%) received 4-point fixation, and 15 (16%) received bone-supported arch bars. The mean operative time for Erich arch bars (98.7 minutes; 95% CI, 89.2-108.2 minutes) was significantly longer than for 4-point fixation (48.8 minutes; 95% CI, 41.8-55.7 minutes) and bone-supported arch bars (55.9 minutes; 95% CI, 43.1-68.6 minutes). A total of 17 patients who received Erich arch bars (63%), 37 patients who received 4-point fixation (72%), and 1 patient who received bone-supported arch bars (7%) needed to return to the operating room for hardware removal. Patients who received Erich arch bars and those who received 4-point fixation had significantly higher odds of requiring a secondary procedure than did patients who received bone-supported arch bars (Erich arch bars: odds ratio, 27.1; 95% CI, 2.7-274.6; and 4-point fixation: odds ratio, 42.8; 95% CI, 4.4-420.7). Mean total operative charges for application of the hardware alone were significantly less for 4-point fixation ($5290; 95% CI, $4846-$5733) and bone-supported arch bars ($6751; 95% CI, $5936-$7566) than for Erich arch bars ($7919; 95% CI, $7311-$8527). When secondary procedure charges were included, the mean total charge for Erich arch bars ($9585; 95% CI, $8927-$10 243) remained significantly more expensive than the mean total for 4-point fixation ($7204; 95% CI, $6724-$7684) and bone-supported arch bars ($6924; 95% CI, $6042-$7807). No clinically meaningful difference in complications between groups was found (Erich arch bars, 3 [11%]; 4-point fixation, 5 [10%]; and bone-supported arch bars, 2 [13%]).

Conclusions and Relevance

Bone-supported arch bars have comparable complication outcomes, operative time for placement, and overall charges when compared with Erich arch bars and 4-point fixation, and have a lower likelihood of requiring removal in an operative setting.

The Hybrid Arch Bar Is a Cost-Beneficial Alternative in the Open Treatment of Mandibular Fractures

Obtaining maxillomandibular fixation (MMF) to achieve fracture reduction and functional occlusion is essential in the management of maxillofacial trauma. The aims of this retrospective review were to compare the total time spent in the operating room (OR) when using the Erich arch bar (EAB) versus the bone anchored hybrid arch bar (HAB) as well as performing a cost-benefit analysis (CBA). The study sample comprised patients older than 18 years who underwent open reduction internal fixation of mandible fractures at two separate institutions over a 5-year period. The primary outcome variable was total surgical time in minutes, defined as the time from incision to the completion of closure. Average operative time was significantly longer for the EAB than for the HAB (186.74 ± 70.73 vs. 135.98 ± 2.69 minutes, p  < 0.001). A significant amount of time was saved by using the HAB for unilateral (37.17 ± 13.19 minutes; p  = 0.007) and bilateral fractures (55.83 ± 18.89 minutes; p  = 0.005). In-depth CBA showed that, for average OR fees of $60 per minute, the HAB produced savings of at least 4.01 and 11.63% of the total cost of surgery for unilateral and bilateral fractures. These results support the hypothesis that the HAB is a time-saving maneuver in the open treatment of mandible fractures. The HAB saves more time in bilateral fracture cases despite the longer overall operative times. This study shows the differential time-saving effect of the HAB regardless of fracture laterality as well as its cost minimization benefit compared with the EAB.

FAMI Screws for Mandibulo-Maxillary fixation in mandibular fracture treatment - Clinico-radiological evaluation

Mandibulo-maxillary fixation (MMF) is indispensable for mandibular fracture treatment. Various means for MMF have been proposed, of which arch bars are widely considered to be the mainstay. However, disadvantages to this method have initiated a quest for an alternative, leading to the introduction of MMF screws. MMF screws have frequently been criticized for poor stability of fracture sites, root damage, hardware failure, and nerve damage. We retrospectively evaluate the FAMI (Fixation and Adaptation in Mandibular Injuries) screw in mandibular fracture treatment by scanning for clinically and radiologically visible complications. In total, 534 FAMI screws were used in the successful treatment of 96 males and 34 females. Condylar fractures were most commonly encountered, representing 120 of 241 fracture sites. 15 general fracture-related complications occurred, with the most common being nerve function impairment (3.8%) and postoperative malocclusion (4.6%). In nine cases (7%), clinically visible FAMI-screw-related complications occurred, with the most prevalent being screw loosening (2.3%) and mucosal signs of inflammation (3.1%). Duration of FAMI screws was associated with the occurrence of clinically visible complications (p = 0.042). Radiologically, clinically invisible dental hard tissue damage was noted in 21 individuals (16%). Therefore, FAMI screws seem to be a reliable and safe method for mandibulo-maxillary fixation.

Updates in Management of Craniomaxillofacial Gunshot Wounds and Reconstruction of the Mandible

This article includes updates in the management of mandibular trauma and reconstruction as they relate to maxillomandibular fixation screws, custom hardware, virtual surgical planning, and protocols for use of computer-aided surgery and navigation when managing composite defects from gunshot injuries to the face.

The use of Synthes MatrixWAVE bone anchored arch bars for closed treatment of multiple concurrent mandibular fractures

Background

Maxillomandibular fixation (MMF) is an important tool in the treatment of facial fractures and bone-anchored arch bar systems have emerged as treatment options. This study illustrates our experience with the Synthes MatrixWAVE MMF system and the novel application in closed treatment of patients with multiple concurrent mandibular fractures.

Methods

We enrolled eight patients with concurrent mandibular fractures and treated them with the MatrixWAVE MMF system. The malleable arch bars were fitted and then secured using 6-8 mm screws. The arch bar was and either stretched or compressed to ensure optimal positioning. 24-gauge interdental fixation wiring was placed using the fish loop technique on either side of the fracture to achieve stabilization of the mandible fractures.

Results

All eight patients were retained in MMF until stable occlusion was achieved with clinical evidence of healing, approximately 4-6 weeks. Post-operative Panorex scans did not reveal any evidence of damage to tooth roots. None of the screws became overly embedded in the mucosa secondary to overgrowth; the arch bars were successfully removed in an outpatient setting without local anesthesia.

Conclusions

The Synthes MatrixWAVE MMF system has unique features such as prominent screw anchor heads and horizontal malleability unique from other bone anchored arch bars. These features allow for completely closed treatment of patients with multiple concurrent mandible fractures.

A Technique for Reduction of Edentulous Fractures Using Dentures and SMARTLock Hybrid Fixation System

Establishing anatomic reduction of an edentulous mandible fracture is a frequently acknowledged challenge in craniomaxillofacial trauma surgery. In this study, we report a novel method for the reduction of the edentulous mandible fracture, via fabrication of modified Gunning splints using existing dentures and SMARTLock hybrid arch bars. This technique dramatically simplifies the application of an arch bar to dentures, obviates the need for the fabrication of impressions and custom splints, and eliminates the lag time associated with the creation of splints. Furthermore, this method may be used with or without adjunctive rigid internal fixation. The technique described herein of creating Gunning splints with SMARTLock hybrid arch bars provides surgeons with a simple, rapid, single-stage solution for reduction of mandibular fractures in the edentulous patient.

Dental occlusion ties: A rapid, safe, and non-invasive maxillo-mandibular fixation technology

Objectives

For decades, Erich arch bars have been a standard in establishing maxillo‐mandibular fixation (MMF). While reliable, the approach risks sharps injury, consumes operating room time, and inflicts gingival trauma. Newer technologies including screw‐based techniques and “hybrid” techniques have improved MMF by reducing sharps injuries and operating room time, but risk injury to tooth roots, nerves, and gingiva. This study aims to establish the application, strengths, and limitations of dental occlusion ties as a novel alternative in maxillo‐mandibular fixation.

Study Design

Prospective, non‐blinded, human feasibility clinical trial.

Materials and Methods

An iterative prototyping process was used to invent dental occlusion ties (brand name: Minne Ties). Development included 3D printing, cadaver prototype testing, human apical embrasure measurement, and ultimately non‐significant risk human clinical trial testing. In the IRB‐approved feasibility clinical trial, the devices were applied to mandible and maxilla fracture candidates with fractures amenable to intra‐operative MMF with open reduction with internal fixation. The ties were removed prior to extubation. Pre‐teens, comminuted fracture patients, and patients requiring post‐operative MMF were excluded.

Results

Manufactured, sterile prototypes secured MMF successfully in management of unilateral and bilateral mandible and maxilla fractures. All patients reported correction of pre‐operative malocclusion. Application times were typically 12–15 minutes for a single surgeon to achieve MMF. Patients incurred negligible gingival trauma from the technology as the ties require no tissue penetration for application.

Conclusions

Dental occlusion ties offer a non‐invasive solution featuring operating room efficiency, minimized sharps risk, and less bony and soft tissue trauma than current commercialized solutions.

Level of Evidence

Therapeutic, IV