Sagittal reduction genioplasty: Technical note.

Without a doubt, the chin plays an important role on facial harmony. Both position and shape of the chin can significantly affect the facial profile. Genioplasty is a relatively simple surgical procedure that allows to correct deformities associated to the chin area. Several techniques and modifications have been described in the literature for different types of deformities. Anterior posterior reduction osteotomies of the chin have an unpredictable effect on the soft tissues and the use of the conventional sliding osteotomy have shown unsatisfactory cosmetic outcomes, this associated with step deformity, notching at the inferior border of the mandible among others. We propose a simple and effective technique that allows the correction of a chin deformity in cases where sagittal or vertical reduction is required with excellent esthetic results. Four case examples are presented for technique illustration.

Chin Microgenia: An Anthropometric Analysis on the Prevalence and Severity in a Chinese Population.

BACKGROUND: The chin is an important component of facial harmony, and deficient chins are associated with unattractiveness. Previous studies have reported microgenia as the most common subtype of chin deformities. OBJECTIVE: To investigate the prevalence and severity of microgenia in a Chinese population through facial anthropometric analysis. METHODS: A total of 800 Han Chinese adults from various age groups of both sexes were recruited for facial anthropometric measurements and photographic analysis. Chin deficiencies in both sagittal and vertical dimensions were evaluated using G-S-P angle, chin retrusion distance, and Sn-Vl/Sn-Me ratio criteria. RESULTS: In the sagittal dimension, microgenia was present in 60.7% of men and 68.6% of women according to the G-S-P angle criterion, and the angle significantly decreased with age in women (p < .05). According to the chin retrusion criterion, microgenia was present in 38.7% of men and 32.3% of women, and the retrusion distance significantly increased with age in both sexes (p < .05). Vertical microgenia was present in 69.6% of men and 81.9% of women according to the Sn-Vl/Sn-Me criterion, and the ratio gradually increased with age in both sexes (p < .05). CONCLUSION: Microgenia is common among Chinese, particularly in women, and the prevalence and severity increase with age.

Hyaluronic Acid Soft Tissue Filler for the Treatment of The Hypoplastic Chin: An Observational Study.

BACKGROUND: The hypoplastic chin is associated with facial unattractiveness. OBJECTIVE: To evaluate safety and efficacy of JUVÉDERM Voluma XC Injectable Gel (hyaluronic acid filler, HAF) for treatment of hypoplastic chin. METHODS: This was a one-year, open-label, single-center study. RESULTS: Thirty subjects received HAF injections of which 24 subjects (80%) completed the study. Mean facial angle significantly improved at all time points compared with baseline, improving by 1.83° (95% confidence interval, 0.91, 2.75; p < .001) at 12 months. Subject satisfaction with lower face and jawline increased significantly for all FACE-Q questions and time points compared with baseline (p < .05). Subject satisfaction with overall facial appearance, and percentage of subjects "not bothered" by area under chin increased significantly for most FACE-Q questions and time points compared with baseline (p < .05). CONCLUSION: In this completed one-year study, HAF injection for hypoplastic chin was safe and accompanied by significant improvement in facial angle, measures of subject satisfaction, and GAIS.

Incidence of deformities and variation in shape of mentum and wing of Chironomus columbiensis (Diptera, Chironomidae) as tools to assess aquatic contamination.

Constantly, aquatic ecosystems are under pressure by complex mixtures of contaminants whose effects are not always easy to evaluate. Due to this, organisms are sought in which early warning signs may be detected upon the presence of potentially toxic xenobiotic substances. Thereby, the study evaluated the incidence of deformities and other morphometric variations in the mentum and wing of Chironomus columbiensis exposed to water from some of the Colombian Andes affected by mining, agriculture, and cattle raising. Populations of C. columbiensis were subjected throughout their life cycle (24 days) for two generations (F1 and F2). Five treatments were carried out in controlled laboratory conditions (water from the site without impact, site of mining mercury, mining mercury + cyanide, cattle raising, and agriculture) and the respective control (reconstituted water). Thereafter, the percentage of deformities in the mentum was calculated, and for the morphometric analysis 29 landmarks were digitized for the mentum and 12 for the wing. As a result, four types of deformities were registered in the C. columbiensis mentum, like absence of teeth, increased number of teeth, fusion and space between teeth, none of them detected in the individuals from the control. Additionally, the highest incidence of deformity in F1 occurred in the treatment of mining mercury, while for F2 this took place in the treatments of mining mercury + cyanide, cattle raising and agriculture. Differences were also found with respect to the morphometric variations of the mentum and wing of C. columbiensis among the control and the treatments with water from the creeks intervened. The treatments of mining mercury + cyanide and agriculture had the highest morphological variation in the mentum and wing of C. columbiensis. The results suggest that the anthropogenic impacts evaluated generate alterations in the oral apparatus of the larval state of C. columbiensis and in the adult state provoke alterations in the wing shape (increased width and reduced basal area). These deformities may be related to multiple stress factors, among them the xenobiotics metabolized by the organisms under conditions of environmental contamination.

Wedge Osteotomy for Correction of Chin Asymmetry.

Chin deviation is generally the visible reflex of a mandibular asymmetry. The difficulty in obtaining a symmetrical result exists, but it can be minimized with the appropriate surgical technique. This article reports the mentoplasty technique with wedge osteotomy performed in an individual with a right-sided chin deviation. Three osteotomies were performed vertically and equidistantly, forming a bone wedge on the contralateral side of the deviation. Horizontal repositioning associated with the rotation caused by the vertical impaction of the chin after bone wedge removal was effective in solving esthetic problems of facial asymmetry, meeting the patient's main complaint.

Intraoral Prosthetic Chin Augmentation With Vertical Incisions.

To explore a new surgical approach for chin augmentation using a prosthesis with 3 intraoral vertical incisions whereby placement of the prosthesis is more convenient and accurate, with fewer postoperative complications. Following the anatomic characteristics of the chin, a bilateral mucosal vertical incision and a median observation incision are made. The V-shaped mark on the upper side of the prosthesis can be seen through the observation incision after it is placed from the lateral incision into the predesigned compartment. The incision can be sutured if there is no bleeding in the operation area. Surgery performed in all 19 patients with mild microgenia with 6 to 12 months of follow-up resulted in satisfactory chin and face shape without any complications. The application of this novel method can correct McCarthy type I microgenia with more accurate positioning, less possibility of bilateral sideways and/or up/down movement, and fewer complications.

Treatment Approach to Severe Microgenia Cases: Combined Use of Osseous and Implant Genioplasty.

INTRODUCTION: As well as the chin is an important esthetic unit of the facial structure, it is also the region having a key role in the appearance of the face. Correction of cosmetic and functional deformities that may occur in this region because of serious hypoplasia (microgenia) is performed by chin augmentation. Chin augmentation is most frequently performed via implant or osseous genioplasty in the literature. Both 2 techniques have their own advantages and disadvantages. In the literature, various studies comparing these 2 techniques and their long-term results are present, but in some severe microgenia cases, these techniques can be insufficient only for augmentation. In such cases, combined use of implant and osseous genioplasty techniques can come up and data and experiences regarding such combined uses are limited in the literature. In our study, we aim to report our experiences and long-term results regarding 3 cases to whom chin augmentation combined with implant and osseous method is applied because of serious chin hypoplasia (microgenia). METHOD: Three patients to whom chin augmentation combined with osseous and implant genioplasty was applied because of severe microgenia between 2011 and 2016 are included in our study. Before the chin restoration, orthognathic surgery or maxillomandibular distraction applications owing to existing obstructive sleep apnea, malocclusion, or facial asymmetry, are performed in the patients. In preoperative period, chin augmentation amount required is planned for all the patients via cephalometric analysis and the operations of all the patients are performed under general anesthesia via intraoral access. RESULTS: Among 3 patients, 2 were male and 1 was female and their mean age was 27.3 years (22-33). In all the patients, primarily horizontal subapical sliding osteotomy was performed and advancement was performed. After osteotomy, mean 8-mm osseous advancement was obtained and Medpor implant was placed in the chin at the same session for additional augmentation. Mean advancement amount obtained by the Medpor implants was 9 mm. A total average of 17-mm augmentation was obtained in the patients via osseous and implant genioplasty. The reflection of this advancement amount on the soft tissue was measured as 13 mm. Mean follow-up period is 24 months and the patients did not encounter with a major complication in the postoperative period. In the postoperative period, early-period band application was performed at the chin of the patients to reduce edema and to support immobilization. CONCLUSIONS: Chin contour is an important part of facial aesthetics and osseous genioplasty is the ideal treatment option for the correction of most chin deformities. However, in some serious microgenia cases, osseous genioplasty may be insufficient to correct the existing deformity. In such cases, it is seen that the combined correction procedures to be applied together with the implant use can be applicable in terms of the safety and its long-term results.

Correction of chin ptosis.

Chin ptosis is described as a descent of the soft tissue from the symphyseal region to a position under the lower contour of the mandible. Given its multifactorial causes, treatment must be determined on a patient-by-patient basis. While augmentation of the submental crease is a versatile option for the correction of chin ptosis, this only corrects the soft tissue component. A technical modification to treat dynamic chin ptosis, associated with bone reduction in the mandibular symphysis, is presented here.

Early Orthognathic Surgery: A Review.

INTRODUCTION: Management of growing patients with severe developmental jaw abnormalities can be very difficult. Early surgical intervention may be warranted in situations where function (e.g., mastication, swallowing, breathing, or speech) and/or psychological well-being could be negatively affected. Many surgeons and orthodontists are reluctant to recommend a surgical treatment option for growing patients with severe developmental jaw abnormalities because of their age. Specific surgical procedures can be performed during growth to correct developmental jaw abnormalities with predictable results. A sound understanding of the facial growth and the effects of the surgical procedures on subsequent growth is essential when managing growing patients with severe developmental jaw abnormalities. Children with severely progressive congenital deficiencies affecting function/health should be distinguished from ones with severe developmental jaw abnormalities that can be managed later in life. In this review, we will focus on the management of growing patients with developmental jaw abnormalities who seek orthodontic treatment, rather than patients with progressive congenital deformities affecting function and/or health.

Computer Image-Guided Template for Horizontal Advancement Genioplasty.

BACKGROUND: Horizontal advancement genioplasty can be extremely rewarding for microgenia. However, it is challenging for even very experienced surgeon to determine the three-dimensional position of the distant bone fragment during the operation. This study aimed to apply and evaluate computer-aided design (CAD) and computer-aided manufacturing techniques for horizontal advancement genioplasty to improve surgical accuracy. METHODS: Seven patients with microgenia were prospectively enrolled in the study. Preoperative and postoperative computed tomography (CT), photographs, and lateral cephalograms were performed. Computer-aided design was done based on preoperative CT data, and then surgical templates (cutting guide templates and fixation templates) were designed accordingly to guide horizontal advancement genioplasty. All surgeries were performed by junior surgeons. The accuracy of the authors' method was evaluated by the relative error (the mean value of discrepancy between postoperative CT and preoperative design at 6 points selected randomly/preoperative design movement × 100%), Pg position error (postoperative Pg Advancement - preoperative CAD Pg Advancement)/preoperative CAD Pg Advancement × 100%), and Me position error (postoperative Me downward movement - preoperative CAD Me downward movement)/preoperative CAD Me downward movement × 100%). They are all calculated by Geomagic automatically. RESULTS: All 7 patients were satisfied with their aesthetic outcomes. The average absolute relative error is 1.8%. The average absolute Pg position error is 1.9% and the average absolute Me position error value is 1.3%. CONCLUSIONS: The authors' study showed that applying computer-assisted techniques for horizontal advancement genioplasty provided accurate surgical result. With this technique, best result for horizontal advancement genioplasty could be achieved by even inexperienced surgeons.

Development and Validation of a Photonumeric Scale for Assessment of Chin Retrusion.

BACKGROUND: A validated scale is needed for objective and reproducible comparisons of chin appearance before and after chin augmentation in practice and clinical studies. OBJECTIVE: To describe the development and validation of the 5-point photonumeric Allergan Chin Retrusion Scale. METHODS: The Allergan Chin Retrusion Scale was developed to include an assessment guide, verbal descriptors, morphed images, and real subject images for each scale grade. The clinical significance of a 1-point score difference was evaluated in a review of multiple image pairs representing varying differences in severity. Interrater and intrarater reliability was evaluated in a live-subject validation study (N = 298) completed during 2 sessions occurring 3 weeks apart. RESULTS: A difference of ≥1 point on the scale was shown to reflect a clinically meaningful difference (mean [95% confidence interval] absolute score difference, 1.07 [0.94-1.20] for clinically different image pairs and 0.51 [0.39-0.63] for not clinically different pairs). Intrarater agreement between the 2 live-subject validation sessions was substantial (mean weighted kappa = 0.79). Interrater agreement was substantial during the second rating session (0.68, primary end point). CONCLUSION: The Allergan Chin Retrusion Scale is a validated and reliable scale for physician rating of severity of chin retrusion.

Evaluation of mandibular contour in patients with significant facial asymmetry.

Most previous studies on facial asymmetry have not specifically differentiated mandible deviation from structural asymmetry of the mandible. The purpose of this study was to assess the symmetry of the mandible by examining its contour in a cohort of patients with significant facial asymmetry. Eleven cases of facial asymmetry with chin deviation ≥10mm were enrolled. A voxel-paired median plane (optimal symmetry plane, OSP) and two landmark-based median planes were generated. The OSP was created by computing the best pairing of the bony voxels on the two sides. One side of the mandibular contour was mirrored onto the other side using the test plane. The contour differences were measured by distance and by area ratio. They were examined both in frontal and frontal downward inclined view. The contour symmetry of the mandible was that revealed by the plane that presented the best symmetry. The results showed that the OSP worked best in bisecting the contour into two symmetrical halves. Contour analysis showed relatively small discrepancies between the two sides. In conclusion, the mandibles retained an acceptable contour symmetry despite the presence of significant mandibular deviations. It is suggested that proper mandibular alignment be the primary objective in the correction of facial asymmetry.

Not by the Red on My Chinny Chin Chin: A Case of Mandibular Osteomyelitis in a 5-Year-Old Girl.

BACKGROUND: Osteomyelitis is not an uncommon emergency department diagnosis in pediatric patients, and most cases are in the lower extremities. Children can present with acute, subacute, or chronic erythema, pain, swelling, or decreased use of the extremity; some patients will also have fever or elevated serum inflammatory markers, or both. CASE REPORT: We present the case of a healthy 5-year-old girl who presented to the emergency department with 3 weeks of painless chin swelling and 2 days of erythema and pain. While laboratory testing was normal, magnetic resonance imaging demonstrated osteomyelitis of the mandible, later confirmed by biopsy. After 4 weeks of intravenous antibiotics and an additional 2 weeks of oral antibiotics, the patient recovered completely without any residual findings. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case demonstrates that osteomyelitis can develop in previously healthy, fully vaccinated children with competent immune systems. Systemic findings (ie, fever and elevated serum inflammatory markers) may be absent, and osteomyelitis should always be considered in the differential diagnosis for a child presenting with subacute to chronic cutaneous findings without other clear explanation.

Chin Advancement, Augmentation, and Reduction as Adjuncts to Rhinoplasty.

Chin deformities are commonly encountered defects in patients seeking rhinoplasty. Careful preoperative evaluation may identify patients who could benefit from concurrent augmentation or reduction mentoplasty. Alloplastic chin implants and sliding genioplasty represent the main accepted methods of chin augmentation. Although both procedures may be used for retrognathia or microgenia, the sliding genioplasty may also be used in chin asymmetry, prognathia, and vertical height discrepancies. This article outlines the methods to analyze the chin, and discusses the treatment options available for correction of chin deformities as an adjunct to rhinoplasty.

Autogenous Fat Grafting for Chin Augmentation: A Preliminarily Clinical Study of Cosmetic Outcome.

Preoperative evaluation and surgical details of chin fat augmentation aiming at increasing the projection of the original mentum are scarcely reported. Herein, the authors systematically reviewed the application of fat grafting for chin augmentation in our institution from 2010 to 2014. This percutaneously multilayered fat-injection technology can be applied for chin augmentation for a subset of patients after strict selection, and the details of lipofilling technology and fat distribution vary depending on each individual patient's condition. Mentum can be augmented in the sagittal plane in different degrees, whereas the chin height seems unable to be effectively prolonged by lipofilling.

Limitations of osseous genioplasty in relation to the displacement distance: a computer-based comparative study.

OBJECTIVE: The aim of this study was to compare the contact surface area (CSA) between bony segments after performing 4 different osteotomy techniques for genioplasty. STUDY DESIGN: Virtual genioplasties were done in terms of sliding or chin-shield genioplasty and 1- or 2-tiered genioplasty on computed tomography (CT) data from 42 patients. Advancement or setback genioplasty was simulated at 3, 5, 8, and 10 mm. The resulting bony contact areas were calculated by using software. RESULTS: No statistically differences were found between both 2-tiered techniques at any displacement distance. Significant statistical differences were noticed between 1-tiered genioplasty and corresponding upper and lower osteotomy at 2-tiered genioplasty and between lower osteotomies of both 2-tiered techniques (P < .001). However, at a displacement distance of 8 mm, the CSA of the lower 2-tiered genioplasty was found to be larger than that of the corresponding after 1-tiered genioplasty (P < .001). CONCLUSIONS: From a displacement distance of 8 mm, a relatively larger CSA could be achieved after performing 2-tiered genioplasty technique.

Chin Microgenia: A Clinical Comparative Study.

BACKGROUND: The aesthetic relevance of the chin and its relatively simple correction through different approaches make genioplasty one of the most performed aesthetic procedures of the face. Sliding genioplasty is extremely rewarding, particularly when performed as an adjunction to rhinoplasty, rhytidectomy, or jaw surgery. In the scientific literature, many different surgical techniques are described, but the biological implications and the economical impact can shape the surgeon's decision on which can be the best treatment: surgical correction with osteotomy, chin implants, or with fillers. OBJECTIVE: The authors propose a decision making protocol for correcting chin microgenia based on a revision of 345 treated cases. METHODS: A retrospective review of 345 cases of chin microgenia was undertaken to understand the proper preoperative assessment and therapeutic planning. A total of 135 patients were treated with surgical sliding genioplasty (group A): 60 patients (group B) have been grafted with alloplastic implants and the remaining 150 patients (group C) with hyaluronic acid. We recorded clinical indications, complications, and long-term aesthetic results at 3-year follow-up. RESULTS: The analysis of the results based on the entity of the chin's sagittal defect, the chin soft-tissue thickness, the patient's age, and self-judgment allows for simplified treatment planning for sagittal chin deformities showing a greater predictability and a more stable long-term aesthetic result regarding sliding genioplasty compared to alloplastic implant placement and fillers. CONCLUSIONS: Our proposal for a simple and versatile protocol of chin microgenia aims to simplify the therapeutic indications for a predictable and a stable long-term aesthetic result. LEVEL OF EVIDENCE II: 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 Table of Contents or the online Instructions to Authors www.springer.com/00266 .