Surgical Correction of Maxillofacial Skeletal Deformities

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.

Clinical Stability of Bespoke Snowman Plates for Fixation following Sagittal Split Ramus Osteotomy of the Mandible

Maxillofacial skeletal surgery often involves the use of patient-specific implants. However, errors in obtaining patient data and designing and manufacturing patient-specific plates and guides can occur even with accurate virtual surgery. To address these errors, bespoke Snowman plates were designed to allow movement of the mandible. This study aimed to compare the stability of bespoke four-hole miniplates with that of a bespoke Snowman plate for bilateral sagittal split ramus osteotomy (SSRO), and to present a method to investigate joint cavity changes, as well as superimpose virtual and actual surgical images of the mandible. This retrospective study included 22 patients who met the inclusion criteria and underwent orthognathic surgery at a university hospital between 2015 and 2018. Two groups were formed on the basis of the plates used: a control group with four-hole bespoke plates and a study group with bespoke Snowman plates. Stability was assessed by measuring the condyle-fossa space and superimposing three-dimensional virtual surgery images on postoperative cone-beam computed tomography (CBCT) scans. No significant differences were observed in the condyle-fossa space preoperatively and 1 year postoperatively between the control and study groups. Superimposing virtual surgery and CBCT scans revealed minimal differences in the landmark points, with no variation between groups or timepoints. The use of bespoke Snowman plates for stabilizing the mandible following SSRO exhibited clinical stability and reliability similar to those with bespoke four-hole plates. Additionally, a novel method was introduced to evaluate skeletal stability by separately analyzing the condyle-fossa gap changes and assessing the mandibular position.

[Progress of diagnosis and treatment of upper respiratory obstruction in patients with Treacher Collins syndrome]

Objective

To summarize the progress of diagnosis and treatment of upper respiratory obstruction in patients with Treacher Collins syndrome (TCS).

Methods

The domestic and abroad literature about the diagnosis and treatment of upper respiratory obstruction in patients with TCS was extensively reviewed and analyzed.

Results

TCS is an autosomal-dominant craniofacial developmental syndrome. It is often accompanied by midface and/or mandibular hypoplasia, soft tissue hypertrophy, and other respiratory tissue developmental abnormalities, which can lead to different degrees of upper respiratory obstruction symptoms. Respiratory obstruction in patients with TCS is affected by many factors, and the obstructive degree are different. Early detection of the causes and obstructive sites and adopted targeted treatments can relieve the symptoms of respiratory obstruction and avoid severe complications.

Conclusion

Due to the low incidence of TCS, there is still a lack of high-quality research evidence to guide clinical treatment. Large-scale and prospective clinical studies are needed to provide new ideas for the treatment and prevention of upper respiratory obstruction.

Orthognathic Surgery Treatment Need in a Turkish Adult Population: A Retrospective Study

Objectives: Limited information exists on orthognathic procedures and respective dentofacial deformities in Turkey. This retrospective study assessed the orthognathic surgery procedures in two universities, using the Index of Orthognathic Functional Treatment Need (IOFTN), and compared the IOFTN grades according to gender as well as sagittal and vertical skeletal relationships. Material and Methods: Records of 200 consecutive patients (120 females, 80 males, mean age = 23.4 (SD: 5.4) years) who received orthognathic treatment (2014–2018) were analyzed. Sagittal (ANB angle) and vertical skeletal type (GoGnSN angle), osteotomies, and IOFTN scores were recorded. Results: Class III, II, and I malocclusions formed 69%, 17.5%, and 13.5% of the samples, respectively. Class III skeletal relationships (69%) and high-angle cases (64%) were the most prevalent (p < 0.05). IOFTN scores were unevenly distributed among genders (p < 0.05) and the prevalent scores were 5.3 (40.5%), 4.3 (15.5%), 5.4 (13%), and 5.2 (7.5%), with 94% scoring 4 or 5 (great and very great functional need). Bimaxillary osteotomies were the most prevalent (55%), followed by LeFort I (32%), and 26% had genioplasty. Conclusion: IOFTN is a reliable tool to identify patients in need of orthognathic surgery. Class III malocclusions and Class III sagittal skeletal relationships were more common in this sample. Comparatively, a higher number of patients had genioplasty as a part of their treatment.

Volumetric changes of the upper airway following maxillary and mandibular advancement using cone beam computed tomography

The objective of this project was to retrospectively evaluate changes in volume of different compartments of the upper airway in response to maxillary, mandibular, and bimaxillary advancement surgeries and to predict the extent of volumetric changes associated with these surgical movements. Pre- and post-surgical cone beam computed tomography scans of 36 patients were evaluated for changes in nasal cavity, nasopharyngeal, oropharyngeal, and hypopharyngeal compartments. The amount of movement for each surgery was measured from skeletal landmarks to reference planes and was correlated with volumetric changes. Maxillary advancement of 4.0±2.2mm increased the oropharyngeal volume significantly (41.40%), and mandibular advancement of 3.8±1.6mm also significantly increased the oropharyngeal volume (21.17%). Bimaxillary advancement of 5.1±1.3mm for the maxilla and 6.4±3.1mm for the mandible significantly increased nasopharyngeal (27.45%), oropharyngeal (66.39%), and hypopharyngeal (52.48%) volumes. Furthermore, for every millimeter anterior movement, oropharyngeal volume increased by 2319.2±771.8mm³. Bimaxillary advancement showed a greater increase than isolated maxillary and mandibular advancement in all pharyngeal compartments. Every millimeter of advancement in the bimaxillary group led to a significant increase in oropharyngeal volume, while every millimeter downward movement showed a significant increase in nasopharyngeal volume.