Narrowing and lengthening genioplasty with pedicled bone graft in contouring of the short and wide lower face

A Differential Analysis of Preferred Feminine Facial Contours for Transfeminine Individuals

BACKGROUND

Facial feminization surgeries are important gender-affirming procedures for transfeminine individuals. The literature provides guidance on classically feminine facial features but the aesthetic preferences of transgender patients have not been studied. This study aimed to define the preferred feminine facial proportions of transfeminine patients and compare them to a mixed population of US adults.

METHODS

An online survey was designed consisting of virtually modified images with progressive degrees of change in 6 facial features: forehead, nasal dorsum, chin projection, nasolabial angle, mandibular angle, and chin height. It was administered to transfeminine patients in a large-scale health system as well as the general population using an online market research instrument. Respondents ranked each image on a 7-point Likert scale from "very unattractive" to "very attractive" for a feminine face.

RESULTS

Both groups agreed that a moderately convex forehead without supraorbital ridge prominence, slightly sloped nasal dorsum, ∼105-degree nasolabial angle, and decreased chin height were considered most attractive. In addition, very concave nasal slope and ∼110-degree nasolabial angle were rated significantly higher by transfeminine respondents compared with controls. The most classically masculine versions of each feature were considered significantly more unattractive by transfeminine patients when compared with controls.

CONCLUSION

Transfeminine individuals share significant preferences in feminine facial features with control respondents. However, transfeminine patients were more averse to traditionally masculine features on a feminine face and more accepting of the most traditionally feminine versions of nasal contours. Understanding these differences can facilitate surgical planning between surgeons and patients and potentially improve patient satisfaction.

Aesthetic Genioplasty Based on Strategic Categorization

BACKGROUND

Genioplasty is a popular procedure used for lower facial contour correction. Various osteotomy techniques enable us to perform advancement, setback, reduction, or narrowing procedures. Computed tomographic images facilitate preoperative planning in detail. The authors used a novel planning method based on strategic categorization. The analytic results are described.

METHODS

This retrospective study reviewed 208 patients who underwent genioplasty procedures for facial contouring from October of 2015 to April of 2020. During preoperative evaluation of the mandible, the operative procedure selected was one of three types: (1) horizontal segment osteotomy, (2) vertical and horizontal segment osteotomy, and (3) bone graft after repositioning. Adequate osteotomies were followed by rigid fixation using a titanium plate and screws. The follow-up period ranged from 8 to 24 months (average, 17 months). The results were assessed based on medical records, photographs, and facial bone computed tomographic images.

RESULTS

Overall, the patients were satisfied with the outcomes and had responder-based improvement in lower facial contour and balance. Chin point deviations were noted in 176 cases; left-side deviation ( n = 135) was more frequent than right-side deviation ( n = 41). Strategic osteotomies based on precise measurements led to correction of asymmetries. Temporary partial sensory losses reported in 12 cases resolved within an average of 6 months after surgery.

CONCLUSIONS

Each patient's chief complaint and bony structures should be carefully evaluated before genioplasty procedures are performed. During the operation, meticulous osteotomy, precise movement, and rigid fixation are necessary. The strategic process used for genioplasty resulted in aesthetic balance and predictable outcomes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Correcting the Broad, Flat and Short Chin Using Modified M-genioplasty

BACKGROUND

Several genioplasty techniques can narrow the width of the chin. Nevertheless, patients with a broad and short chin who received these methods were unsatisfied with the outcomes. The goal of this study was to analyze the clinical outcomes of modified M-shaped genioplasty for broad, flat and short chin deformity.

METHODS

Thirty-eight patients with broad, flat and short chins were included in this study from January 2019 to December 2021. The preoperative design was performed individually according to the data of the chin and the patient's desire of final chin shape. Narrowing and vertical elongating genioplasty was performed for all the patients with modified M-shaped genioplasty under general anesthesia according to the preoperative designs. All patients have completed the FACE-Q preoperatively and 3 months postoperatively. The results were evaluated by clinical appearances and FACE-Q scores.

RESULTS

The vertical lengthening of the chin was 2-5 mm, with an average of 3.02 mm. The horizontal narrowing width was 3-6 mm, with an average of 5.6 mm. FACE-Q scores in satisfaction with the chin increased significantly from 35.34 ± 9.57 to 72.95 ± 6.81. There were no severe complications took place during the time frame of 3-24 months postoperatively.

CONCLUSIONS

The modified M-shaped genioplasty preserved the bone structure in the midsymphyseal area and suprahyoid muscular attachments as far as possible, and the bone segments may be repositioned quickly. This technique produced reliable and esthetically satisfying results in correcting a short, flat and broad chin, with altered vertical length, slope, width and protrusion three-dimensionally.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Total inferior border ostectomy versus T-shape genioplasty for chin narrowing combined with mandibular contouring

The objective of this study was to compare the indications and outcomes of the total inferior border ostectomy and T-shape genioplasty. A retrospective study was conducted using the clinical notes and records of patients who underwent total inferior border ostectomy (group 1, n = 42) and T-shape genioplasty (group 2, n = 60). The outcomes were evaluated by assessment of computed tomography images combined with medical records and photographs. Lower facial height, chin width, chin symmetry, and facial proportions, as well as patient satisfaction and complications were investigated. The data were collected preoperatively and 6-24 months postoperatively. All 102 patients showed an improved lower facial contour. No severe complications were observed during the follow-up period. Although the postoperative lower to midfacial height ratios were similar in the two groups (P = 0.080), both the preoperative and postoperative chin width to lower facial height ratios were lower in group 1 (both P < 0.001). A larger amount of chin narrowing, as well as better chin symmetry were observed in group 1 (P < 0.001). In conclusion, compared to the T-shape genioplasty, the total inferior border ostectomy is well suited for a longer, wider, and more asymmetrical chin. The surgical options should be considered and chosen quantitatively to achieve aesthetically pleasing results.

A New Concept of Narrowing Genioplasty: Home Plate-Shaped Sliding Osteotomy

BACKGROUND

Narrowing genioplasty is commonly performed among East Asian populations, as a broad and/or square chin can be aesthetically unappealing. This study was aimed to introduce the home plate-shaped sliding osteotomy technique for narrowing genioplasty and to evaluate the results of this technique.

METHODS

A retrospective chart review of 117 patients who underwent home plate-shaped sliding osteotomy alone between 2011 and 2019 was performed. The angles of oblique osteotomy lines and measurements of caudal repositioning, which significantly affect the postoperative chin shape, were evaluated.

RESULTS

The home plate-shaped sliding osteotomy technique was successfully accomplished for narrowing genioplasty as an isolated procedure. The mean distance of caudal repositioning was 3.9 ± 0.8 mm, and the mean angles of oblique osteotomy lines were 23.3 ± 4.8 degrees on the right and 21.8 ± 3.5 degrees on the left. This produced an aesthetically pleasing rounded and proportionately narrow chin. The incidence of minor complications was 6.0 percent. There were no major complications. In particular, the risk of inferior alveolar nerve injury was obviated, as an additional mandibular border osteotomy was not typically used with this technique.

CONCLUSIONS

This new surgical procedure for narrowing genioplasty provides improved aesthetic results by altering the chin shape, rather than reducing the transverse width of the chin. The versatility of this procedure allows the chin shape to be adjusted with respect to narrowing, vertical lengthening, anterior advancement, and asymmetric or cleft chin correction. The present study suggests that home plate-shaped sliding genioplasty may be an excellent alternative for correcting broad and/or square chins and more complex chin deformities.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Are chin and symphysis morphology facial type-dependent? A computed tomography-based study

INTRODUCTION

The chin is a major determinant of the facial profile; hence, it plays a major role in orthodontics and orthognathic surgery. It is thus essential to follow and better understand its expression in different facial types. The major objectives of the current study were to characterize morphometrically the chin and symphysis and reveal their association with different facial types.

METHODS

Computed tomography scans of the head and neck of 311 adults (163 males, 148 females; age range, 18-95 years) were classified into 3 facial types: short, average, and long. Height, width, projection, inclination, thickness, and area were measured on the chin and symphysis.

RESULTS

The majority of the population (70%) manifested an average facial type; the other 30% were almost equally distributed between short and long facial types. The long facial type was more common among females and the short facial type among males. Chin projection, area, and size were significantly greater in short-faced patients. Chin width in males was similar for all facial types, whereas, in females, chin width was the widest in the short facial type and the narrowest in the long facial type. Symphysis height was significantly greater in long-faced patients in both sexes. The mandibular incisors' inclination relative to the mandibular plane was not significantly associated with the chin or symphysis morphology.

CONCLUSIONS

Chin and symphysis morphology is facial type-dependent. Orthodontists and maxillofacial surgeons should be aware of the complex relationship between facial types and chin/symphysis size and shape when planning treatment.

Vertical lengthening genioplasty: A new osteotomy technique

Vertical insufficiency of the chin imbalances the orofacial and aesthetic parameters of the lower third of the face. We here propose a new osteotomy technique for chin lengthening. Our procedure is based on a single osteotomy and it does not require any interposition of a bone graft. In our experience with seven patients, we report good aesthetic and morphometric outcomes at one year.

Lower facial contouring surgery using a novel method: M-genioplasty

Background

Mandibular contouring surgery to produce a more slender and small face has become popular, especially in East Asia. Narrowing genioplasty should be simultaneously performed with mandibular angle resection to achieve satisfactory results. In Korea, T-genioplasty has been frequently performed for chin narrowing. The authors developed a new, safe, and reliable method, termed M-genioplasty, that can provide a more slender and attractive lower face.

Methods

From June 2013 to December 2017, 36 patients underwent M-genioplasty with mandibular angle resection for lower facial contouring. Horizontal and vertical osteotomies were performed obliquely. The resected bone segments were wedge-shaped. The remaining two bone segments were rotated and approximated centrally. The lateral mandible bony stepoff was trimmed off for mandibular angle resection.

Results

In all patients, the facial contour sufficiently improved, and most patients were satisfied with the outcome. No severe complications took place during postoperative follow-up.

Conclusions

M-genioplasty can provide more mandibular angle resection and can create a more acute chin angle without bone resorption than other methods, including T-genioplasty. M-genioplasty with mandibular angle resection is a safer, more accurate, and more reliable method for lower facial contouring.

A new design of CAD/CAM surgical template system for two-piece narrowing genioplasty

The purpose of this study was to develop and validate a new chin template system for a two-piece narrowing genioplasty. Nine patients with wide chin deformities were enrolled. Surgeries were planned with the computer-aided surgical simulation (CASS) planning method. Surgical splints and chin templates were designed in a computer and fabricated using a three-dimensional printing technique. The chin template system included a cutting guide and a repositioning guide for a two-piece narrowing genioplasty. These guides were also designed to avoid the mental foramen area and inferior alveolar nerve loops during the osteotomy, for nerve protection. After surgery, the outcome evaluation was completed by first superimposing the postoperative computed tomography model onto the planned model, and then measuring the differences between the planned and actual outcomes. All surgeries were completed successfully using the chin template system. No inferior alveolar nerve damage was seen in this study. With the use of the chin templates, the largest linear root mean square deviation (RMSD) between the planned and the postoperative chin segments was 0.7mm and the largest angular RMSD was 4.5°. The results showed that the chin template system provides a reliable method of transfer for two-piece osseous narrowing genioplasty planning.

Genioplasty using a simple CAD/CAM (computer-aided design and computer-aided manufacturing) surgical guide

BACKGROUND

The present study introduces the design and fabrication of a simple surgical guide with which to perform genioplasty.

METHODS

A three-dimensional reconstruction of the patient's cranio-maxilla region was built, with a dentofacial skeletal model, then derived from CT DICOM data. A surgical simulation was performed on the maxilla and mandible, using three-dimensional cephalometry. We then simulated a full genioplasty, in silico, using the three-dimensional (3D) model of the mandible, according to the final surgical treatment plan. The simulation allowed us to design a surgical guide for genioplasty, which was then computer-rendered and 3D-printed. The manufactured surgical device was ultimately used in an actual genioplasty to guide the osteotomy and to move the cut bone segment to the intended location.

RESULTS

We successfully performed the osteotomy, as planned during a genioplasty, using the computer-aided design and computer-aided manufacturing (CAD/CAM) surgical guide that we initially designed and tested using simulated surgery.

CONCLUSIONS

The surgical guide that we developed proved to be a simple and practical tool with which to assist the surgeon in accurately cutting and removing bone segments, during a genioplasty surgery, as preoperatively planned during 3D surgical simulations.

Contouring of the lower face by a novel method of narrowing and lengthening genioplasty

BACKGROUND

Lower face contouring surgery has become a popular aesthetic operation in most East Asian countries. Various surgical methods are used to improve lower face aesthetics. However, when a patient has both a short and a wide lower face, a chin-lengthening procedure should be performed simultaneously with narrowing genioplasty. Autogenous bone grafts or alloplastic materials are commonly used to correct this problem, but these surgical methods have several inherent disadvantages. To avoid these complications, the authors devised a novel, simple, and reliable method that can correct a short and wide lower face.

METHODS

From January of 2010 to December of 2012, a consecutive series of 58 patients underwent chin-narrowing and chin-lengthening surgery. First, the newly designed narrowing and lengthening genioplasty was performed. Then, the mandible lower borders were further contoured to diminish the bony steps at the chin-mandible junction and achieve a smooth and slender jaw line.

RESULTS

All patients showed sufficient improvement of their facial contours, and most of the patients were satisfied with their surgical outcomes. No severe complications were noted during the follow-up period. The results were confirmed with postoperative radiographs and medical photographs.

CONCLUSIONS

As the lower face plays an important role in the aesthetics and balance of the entire face, the authors' novel surgical tool to narrow and lengthen the chin can provide aesthetically gratifying results when correcting a short and wide lower face. Complications seen with previous chin-lengthening methods were avoided, and the new surgical tool showed reliable and predictable surgical outcomes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.