Endoscopic Approach for Mandibular Orthognathic Surgery

Minimally Invasive Approaches in Orthognathic Surgery: A Narrative Review of Contemporary Techniques and their Clinical Outcomes

Maxillofacial surgery has evolved significantly, particularly in orthognathic procedures, shifting from invasive methods to minimally invasive techniques (MITs). Innovations, like 3D imaging, computer-aided simulations, piezoelectric surgery, and endoscopic assistance, have revolutionized patient care. These methods notably reduce bleeding, scarring, hospital stays, and recovery time, while enhancing surgical precision and outcomes. Our review focuses on modern MITs, including endoscopically assisted maxillomandibular advancement (EAMMA) and CAD/CAM technology. We conducted a thorough literature search, identifying 21 relevant articles from an initial pool of 423. The review evaluates the efficacy, complication rates, and long-term stability of these techniques, addressing challenges and future prospects. Emphasizing the significance of MI methods in orthognathic surgery, it advocates for further research and clinical adoption.

Minimally invasive genioplasty: an observational study

PURPOSE

This study aimed to determine the feasibility of a minimal invasive genioplasty (MIG) technique combining a limited vertical incision, endoscopy, and a piezotome.

METHODS

A total of thirteen patients who underwent primary genioplasty procedures under general anesthesia were evaluated. The feasibility of the method was reported in terms of total surgery time, the total amount of intra-operative blood loss, neurosensory dysfunction, pain sensation, infection, and patient satisfaction using the FACE-Q Chin scale.

RESULTS

We observed the mean surgery time of 46.08 ± 5.33 min with a statistically significant p-value of 0.157. The ANOVA test value for mean neurosensory testing score (NST) was calculated as 5.95 (p = 0.006) for the right side and 7.64 (p = 0.017) for the left side. The paired t-test value of the mean pain score was 117.98 (p < 0.001) and showed no significant pain after 1 week. The quality of the osteotomy was deemed good in 12 patients with less intra-operative blood (ranged from 7.7 to 46.2%).

CONCLUSION

Based on these results, this minimally invasive technique for genioplasty is a promising approach to perform a chin osteotomy and should be an alternative to the conventional genioplasty technique.

Minimally invasive orthognathic surgery: a systematic review

Minimally invasive techniques are currently applied in many oral and maxillofacial surgical procedures, including orthognathic surgery. A systematic review on the application of potentially minimally invasive procedures in orthognathic surgery was performed to provide a clear overview of the relevant published data. Articles in English on minimally invasive orthognathic procedures, published in the scientific literature, were obtained from the PubMed, Embase, and Cochrane Library databases, and an additional manual search (revised 31 December 2016). After screening the abstracts and applying the eligibility criteria, 403 articles were identified. All articles reporting the potential for minimally invasive orthognathic surgery were included (n=44). The full papers were evaluated in detail and categorized as articles on a minimally invasive surgical approach (n=4), endoscopically assisted orthognathic procedures (n=17), or the use of a piezoelectric device in orthognathic surgery (n=25); two articles were each included in two categories. Although a small incision and minimal dissection is the basic principle of a minimally invasive technique, most articles (90.9%) reported the endoscope and piezoelectric instrument as important tools in minimally invasive orthognathic surgery. Evidence from available studies suggests that patients undergoing minimally invasive orthognathic surgery have less morbidity and make a faster recovery. Further research should aim to obtain higher levels of evidence.

Complications of the retromandibular transparotid approach for low condylar neck and subcondylar fractures: a retrospective study

Objectives

The goal of this study was to evaluate the rates of complications, morbidity, and safety with the transparotid approach.

Materials and Methods

A retrospective study was conducted and consisted of 53 surgically treated patients in the past five years for low condylar neck and subcondylar fractures. Only patients with malocclusion and who underwent open reduction with internal fixation with the retromandibular transparotid approach were included. The examined parameters were postoperative suboptimal occlusion, deflection, saliva fistula, and facial nerve weakness.

Results

Fifty-three patients had an open reduction with internal fixation on 55 sides (41 males, 77.4%; mean age, 42 years [range, 18-72 years]). Four patients (7.5%) experienced transient facial nerve weakness of the marginal mandibular branch, but none was permanent. Four patients had a salivary fistula, and 5 patients showed postoperative malocclusion, where one needed repeat surgery after one year. One patient showed long-term deflection. No other complications were observed.

Conclusion

The retromandibular transparotid approach is a safe procedure for open reduction and internal fixation of low condylar neck and subcondylar fractures, and it has minimal complications.

Endoscopic approach to maxillofacial trauma

Endoscopic approaches to maxillofacial trauma have included their use in temporomandibular joint arthroscopy, zygomatic arch repair, repair after orbital trauma, repair of frontal sinus fractures, and finally in the repair of subcondylar mandibular fractures. These techniques provide exciting new options for the management of facial fractures. Many of the techniques provide a steep learning curve and require specialized equipment. The approach to an orbital blowout fracture allows the use of a Caldwell-Luc approach and the use of a naturally occurring body space (the maxillary sinus) for the visualization and maneuvering of the endoscope, tools, and implants. The use of the endoscope in the management of fractures for facial structures such as mandibular subcondylar fractures, which do not have a naturally occurring body cavity, may present greater challenges when trying to obtain visualization, reduction, and fixation. When used for the treatment of subcondylar fractures, wide exposure and the use of right-angled drills and screw drivers may significantly help with this procedure. This may be considered by some surgeons as an endoscopically "assisted" procedure that can possibly be accomplished with direct visualization and the use of dental mirrors. It remains to be seen as to whether some of these diverse endoscopic applications will represent the standard of care in the future or remain a specialized technique practiced by a minority of surgeons in a few specialized centers. This article reviews various endoscopic applications to maxillofacial trauma and discusses some of the controversies of these techniques.

Stability of orthognathic surgery and distraction osteogenesis: options and alternatives

Relapse in orthognathic surgery is multifactorial and can be attributed to posttreatment growth, condylar changes, lack of rigid fixation, and muscle pull and function. Consideration of these factors can aide the surgeon in the decision-making process with regards to treatment options and alternatives. This article reviews the stability of various orthognathic movements using traditional osteotomies and fixation, and compares them to what is currently in the literature regarding distraction osteogenesis.

How Do Feedback and Instructions Affect the Performance of a Simulated Surgical Task?

PURPOSE

This study was conducted to objectively evaluate the effect of feedback and instructional material on the acquisition of surgical psychomotor skills for a model system based on mandibular fracture repair.

MATERIALS AND METHODS

This study was a prospective cohort study comprised of students in the preclinical years of dental or medical education. The students were divided into 4 groups and exposed to different levels of feedback/written instructions (including none) in the testing environment. Each subject was given a pair of aluminum bars, representing a fractured human mandible, and a standardized set of tools, including a fixed length of stainless steel wire to fix the bars together. The strength of fixation was measured, using a calibrated testing apparatus, as the amount of load that the fixed sample could tolerate to the point of failure. All subjects completed 5 successive trials under the same conditions. Descriptive statistics were recorded to provide comparisons between groups. Bivariate statistics were computed to compare the different study groups; multiple-comparison testing was used to evaluate differences among the groups. A P value <or= .05 was considered statistically significant.

RESULTS

The sample was comprised of 61 students, divided into 4 groups. The students who received neither instructions nor feedback had the lowest average performance scores. Those who received both feedback and instructions had the highest average performance scores. The students who received instructions only fared better than those who received feedback only, but only immediately after receiving instructions. Differences between the groups tended to dissipate after a few trials.

CONCLUSIONS

Written instructions and performance feedback can enhance the acquisition of psychomotor skills related to the performance of a complex task.