Optimizing Esthetic Outcomes and Bone Stability: Chin Advancement Through Inverted V Osteotomy.

Traditional horizontal osteotomies for small and short chins often yield suboptimal results due to limited bone advancement, resulting in deep labiomental folds and heightened bone resorption risks. This study investigates the effectiveness of an innovative inverted V-shaped osteotomy technique in enhancing esthetic outcomes for patients with such chin concerns. Thirty-eight patients who underwent inverted V-shaped osteotomy for recessed chins between January 2018 and June 2022 were included. Excluding cases involving simultaneous mandibular contouring surgery, patients were followed up for a median duration of 1.2±0.5 years. Preoperation and postoperation soft tissue pogonion (Pg') and labiomental fold depth (LMF) changes were measured. IBM SPSS (version 27.0) was used for statistical analysis, with significance defined as P <0.05. Patient satisfaction was assessed using a visual analog scale. Successful advancement genioplasty was performed on all patients without any severe complications. The average change in soft tissue pogonion (Pg') measured 6.2 (1.9) mm, and the mean alteration in labiomental depth was 0.42 (0.4) mm. The procedure achieved a bone to soft tissue movement ratio of 1:0.96. Patient satisfaction was notably high, with a mean VAS score of 8.7. An inverted V-shaped osteotomy enables greater bone advancement for small and short chins, leading to improved esthetic outcomes and offering a mechanically advantageous condition for bone segments.

Combined Genioplasty and External Oblique Line Grafting: An Innovative Method to Improve Lower Facial Contour.

BACKGROUND: Microgenia and the accompanying plump cheeks or hamster-like facial contour are all unattractive appearances among the Asian. Genioplasty with autogenous bone grafting is one of the effective ways to improve microgenia, in which a suitable donor area with less additional damage, lower infection rate, and more excellent effect is crucial. METHODS: Patients who had undergone genioplasty and autogenous external oblique line grafting (G-EOL) were followed up. The operation-related complications, preoperative, and long-term follow-up 3-dimensional spiral computed tomography (3D-CT) were collected and analyzed. RESULTS: Eight female patients who had received G-EOL and received 1 to 3 years of follow-up were included in this study. There were no short-term or long-term complications. CT data of bone of 8 patients and CT data of soft tissue of 6 patients at the preoperative and long term were compared. Through comparing CT data, the width at the level of the intersection of EOL and mandibular body, and the protrusion of the bony chin had improved significantly; the P values were all <0.001. Through measuring the soft tissue and analyzing the data, the ratio of lower and middle facial width, and the distance from the lower lip to Ricketts' line were all improved, with the P values 0.042 and 0.001, respectively. CONCLUSIONS: For patients with microgenia and hamster-like facial contour, the combination of genioplasty and autogenous external oblique line grafting is innovative and effective in improving both the front and side contour of the lower face simultaneously, with excellent stability, bone healing, and low complication rates.

Facial Asymmetry Caused by Mandibular Condylar Hyperplasia: A Two Center Study.

BACKGROUND: Condylar hyperplasia is a non-neoplastic overgrowth of the mandibular condyle. The disorder is progressive and causes gradual jaw deviation, facial asymmetry, and dental malocclusion. The only treatment capable of stopping hyperplastic growth is surgical condylectomy to remove the upper portion of the condyle containing the deranged growth center. When this procedure is conducted in proportion to the length of the healthy side it may also correct the jaw deviation and facial asymmetry. OBJECTIVES: To assess the degree to which condylectomy corrects the asymmetry and to determine the proportion of patients after condylectomy who were satisfied with the esthetic result and did not desire further corrective surgery. METHODS: We conducted a retrospective analysis of medical records of patients who underwent condylectomy that was not followed by corrective orthognathic surgery for at least 1 year to determine the degree of correction of chin deviation and lip cant. Patient satisfaction from treatment or desire and undergo further corrective surgery was reported. RESULTS: Chin deviation decreased after condylectomy from a mean of 4.8° to a mean of 1.8° (P < 0.001). Lip cant decreased after condylectomy from a mean of 3.5° to a mean of 1.5° (P < 0.001). Most patients (72%) were satisfied with the results and did not consider further corrective orthognathic surgery. CONCLUSIONS: Proportional condylectomy could be a viable treatment to both arrest the condylar overgrowth and achieve some correction of the facial asymmetry.

Chin Dysmorphology in the Primary Rhinoplasty Population: Prevalence, Objective Analysis, and Implications.

BACKGROUND: Chin flaws are far more common than recognized. Denial of genioplasty by parents or adult patients can present a surgical planning enigma, especially in patients with microgenia and chin deviation. This study aims to investigate the frequency of chin imperfections on patients seeking rhinoplasty, review the conundrum they generate, and offer management suggestions based on over 40 years of the senior author's experience. METHODS: This review included 108 consecutive patients presenting for primary rhinoplasty. Demographics, soft tissue cephalometrics, and surgical details were obtained. Exclusion criteria included prior orthognathic or isolated chin surgery, mandiblular trauma, or congenital craniofacial deformities. RESULTS: Of the 108 patients, 92 (85.2%) were female. Mean age was 30.8 years (SD±13, range 14-72). Ninety-seven (89.8%) patients exhibited some degree of objective chin dysmorphology. Fifteen (13.9%) had Class I deformities (macrogenia), 63 (58.3%) Class II (microgenia), and 14 (12.9%) Class III (combined macro and microgenia in the horizontal or vertical vectors). Forty-one (38%) patients had Class IV deformities (asymmetry). While all patients were offered the opportunity to correct chin flaws, only 11 (10.1%) underwent such procedures. Five (4.6%) patients had simultaneous osseous genioplasty (mean advancement 7.8mm, range 5-9mm); 7 (6.5%) received fat grafting to the chin (mean volume 4.4cc, range 1-9cc). CONCLUSIONS: A considerable proportion of primary rhinoplasty patients possess quantifiable chin dysmorphology on circumspect examination, high-resolution photographs and cephalometric analysis. Only a small number agree to surgical interventions that pursue full facial harmony. Potential reasons for these findings, patient aversion, and mitigation strategies will be discussed. LEVEL OF EVIDENCE III: 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 .

Nonsurgical Chin Augmentation Using Hyaluronic Acid: A Systematic Review of Technique, Satisfaction, and Complications.

The article titled "Nonsurgical Chin Augmentation Using Hyaluronic Acid: A Systematic Review of Technique, Satisfaction, and Complications" by Ou et al. in Aesthetic Plastic Surgery presents a systematic review focused on categorizing complications associated with hyaluronic acid (HA) dermal fillers. However, concerns arise regarding the methodologies employed in the reviewed studies. It is essential to have precise knowledge of the properties of the active substance for treatment standardization. Gaining a comprehensive understanding of the key characteristics of the HA used is paramount to determine if there is an association between these properties and the risk of complications.Understanding HA's rheological properties, including viscosity, elasticity, and cohesiveness, is crucial for selecting the most suitable facial filler. While we acknowledge the authors' contributions, we strongly believe that further analysis should incorporate these factors.Level of Evidence V 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 .

Custom-Made Implant Fabrication for Chin Augmentation Using Piled-Up Expanded Polytetrafluoroethylene Sheets: An Innovative Surgical Technique and Literature Review.

BACKGROUND: Alloplastic chin augmentation is the most common esthetic surgical treatment to reshape the chin. However, factory-made chin implants are typically standardized rather than custom-made and have potential to cause complications. Although the fabrication of custom-made implants by using computer-assisted planning and 3D-printing technology has become widespread, the process has several disadvantages, including long preoperative prosthesis preparation times, high costs, and unsuitability for patients with asymmetric chins or those who undergo combined mandibuloplasty before implant placement. The present study developed an innovative chin augmentation technique involving stacked expanded polytetrafluoroethylene (e-PTFE) sheets that is suitable for most patients and has minimal side effects. MATERIALS AND METHODS: A retrospective review of a single surgeon's experience was performed over a 2 year period for patients who underwent a procedure involving piled-up e-PTFE sheets for alloplastic chin augmentation. This study analyzed the outcomes, complications (temporary nerve numbness, wound infection, hematoma formation, and implant displacement), and patient satisfaction during follow-up. RESULTS: Between January 2018 and December 2020, 38 patients underwent the procedure involving piled-up e-PTFE sheets for alloplastic chin augmentation. Six patients (15.8%) experienced nerve-related temporary numbness, and one (2.6%) experienced wound infection. None had developed major complications such as implant displacement or wound infection at follow-up. Moreover, the patients demonstrated a high level of satisfaction with the surgical results. CONCLUSION: Piled-up e-PTFE sheets can be used to produce custom-fit porous polyethylene chin implants that result in minimal complications and a very high satisfaction rate. 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 .

Hybrid Chin Advancement: Combining Fat and Sliced Cartilage Grafts for Chin Augmentation During Rhinoplasty.

BACKGROUND: Facial balance significantly impacts aesthetics, particularly in the middle and lower thirds. Patients with chin retrusion often benefit from sagittal plane chin advancement in rhinoplasty, enhancing surgical outcomes and satisfaction. OBJECTIVES: This article presents a method for analyzing chin deformities and discusses a hybrid treatment approach to harmonize facial features, complementing rhinoplasty. METHODS: The chin positions of patients treated by the senior author were assessed. A retrospective analysis included 49 patients with chin retrusion of 2.5-6 mm. Among them, 22 patients initially offered chin implants declined, leading to planned chin augmentation. Fat grafting was exclusively performed for 20 patients lacking sufficient cartilage. The "Hybrid Chin Advancement" technique involved supporting tissues beneath muscles with nasal septum cartilage and fat injections and tissues above muscles with fat injection alone. RESULTS: Pre- and postoperative Legan angle measurements and chin advancements were compared across three groups. While preoperative Legan angles were statistically similar, postoperative Legan angles and advancement changes were significantly higher in the implant group (p < 0.0001). Comparing hybrid chin advancement and fat grafting groups, postoperative Legan angles and advancement changes were significantly higher in the hybrid chin group (p < 0.0001). CONCLUSIONS: Fat grafting suffices for mild advancements (~ 2 mm), while the hybrid chin method is effective for moderate advancements (~ 4 mm). For advancements exceeding 6 mm, implants or osseous genioplasty are optimal. Our study's hybrid approach offers an easy, safe, and reliable method for achieving facial harmony in the lower two-thirds without compromising patient expectations. 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 .

F-Chin/Feminizing the Chin: A Genioplasty Technique with Virtual Planning for Male-to-Female Transgender Patients.

The chin is an essential structure in facial harmony and an important gender marker. Advancing a receding chin is fundamental to improve the facial appearance, particularly in male-to-female transgender patients. However, in patients with microgenia and/or retrognathia, desiring a more feminine appearance, a chin advancement can result in a wider, square shape; an undesirable effect. Genioplasty is a versatile procedure used in facial feminization surgery that allows modifying the natural anatomy of the chin in all three spatial dimensions. The technique herein described proposes a simple genioplasty procedure for feminizing the chin (F-chin genioplasty) in transgender patients where anteroposterior advance is required. Virtual planning was used to establish the landmarks for an anteroposterior advancement with transverse reduction in the chin. A perpendicular line to the Frankfurt plane passing through the incisal edge of the upper central incisor was used to plan the anteroposterior movement, and two vertical lines on the outer wall of the nasal cavity  for the chin transverse measurement. The authors present three case reports with the F-chin genioplasty transgender technique with satisfactory results, ensuring a more feminine facial appearance.Level of Evidence V 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 .

Double Chin Concerns after En Bloc Mandibular U-Shaped Osteotomy: Submental-Cervical Soft Tissue Changes and Anterior Belly of Digastric Muscle Assessment.

OBJECTIVE: To assess submental-cervical soft tissue changes after en bloc mandibular U-shaped osteotomy and examine alterations in the anterior belly of digastric muscle (ABDM). METHODS: A retrospective study analyzed 20 patients who underwent en bloc mandibular U-shaped osteotomy from 2018 to 2023. Preoperative (Tp) and long-term follow-up (Tf) CT data were collected for analysis, measuring mandibular volume, soft tissue thickness at menton (Mes) and cervicale (C), and ABDM parameters (length, cross-sectional area (CSA), volume, distance from centroid point to the mandibular margin). Correlation analyses were performed to investigate the connection between soft tissue thickness changes, ABDM changes, and mandibular osteotomy volume. RESULTS: Long-term follow-up revealed a significant increase in soft tissue thickness at the Mes and C points after U-shaped mandibular osteotomy, especially at the C point. The adaptive length of ABDM decreased, CSA increased, and volume decreased, but the ABDM centroid point shifted downward relative to the mandibular margin, indicating drooping protrusion. The increment of soft tissue thickness was moderately positively correlated with the amount of osteotomy, and the decrement of ABDM length and volume were slightly positively correlated with the amount of osteotomy. CONCLUSION: The degree of soft tissue relaxation after U-shaped osteotomy is related to the extent of osteotomy. Notably, the protrusion of ABDM relative to the mandibular margin affects submental-cervical contour aesthetics. Prior to U-shaped osteotomy, it is crucial to assess the soft tissue condition of the patient's lower face, and the individualized design of the osteotomy volume should be carried out cautiously and safely. 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 .

Does Aesthetic Osseous Genioplasty Impact Upper Airway Volume?

BACKGROUND: Although maxillomandibular advancement is the treatment of choice for obstructive sleep apnea syndrome (OSAS) in the presence of underlying maxillomandibular complex hypoplasia, there is still a gap in the literature regarding the impact of genioplasty upon upper airway volume (UAV). OBJECTIVES: The aim of this study was to evaluate the impact of isolated osseous genioplasty upon UAV. METHODS: A retrospective analysis of all patients subjected to isolated osseous genioplasty between July 2015 and July 2022 was conducted. Cone-beam computed tomography was performed preoperatively and postoperatively to assess the chin and hyoid 3-dimensional (3D) spatial position and UAV changes after surgery. RESULTS: A total of 44 patients were included in the study. Regarding surgical movements of the chin, almost all patients received a sagittal movement (n = 42; 39 forward and 3 backward), while in 8 patients a vertical movement (5 upward and 3 downward) was applied, and in 6 patients the chin was centered. Statistically significant increases in total UAV (P = .014) and at the level of the oropharynx (P = .004) were observed. Specifically, chin centering, upward and forward movements enlarged the oropharynx volume (P = .006, .043 and .065, respectively). Chin advancement enlarged the hypopharynx volume (P = .032), as did upward movement of the hyoid bone (P < .001). CONCLUSIONS: Results of the study suggest that aesthetic osseous genioplasty impacts the UAV: each 3D spatial chin movement differently impacts the upper airway by enlarging or narrowing it. However, further studies addressing the apnea-hypopnea index are required to assess its effectiveness in treating OSAS.

Esthetic Surgery of the Chin in Cis- and Transgender Patients-Application of T-Genioplasty vs. Single-Piece Segment Lateralization.

Background and Objectives: Correction of lower face asymmetry still remains challenging in maxillofacial surgery. This report describes techniques for the lateral transposition of the symphyseal segment to restore lower face symmetry while maintaining gender-related features in cis- and transgender patients. Materials and Methods: A retrospective review of medical records of 31 patients who attended for esthetic corrective surgery after orthodontic camouflage or orthognathic treatment, or during facial feminization of the lower face between June 2021 and June 2023 was performed. Result: All patients underwent lateralization genioplasty (with or without advancement or setback), either with or without narrowing T-osteotomy supplemented with necessary procedures in order to obtain proper facial balance and desired esthetical effects, such as bichectomy, liposuction, and face and neck lift. The mean asymmetry of the chin was 5.15 mm and was surgically corrected either by single segment lateralization or T-shape narrowing genioplasty depending on the gender and esthetical requirements. No complications were reported. Conclusions: Lateral shift genioplasty serves as a powerful tool in primary and secondary corrective surgery for lower face asymmetry that maintains gender-specific facial features. It may serve either as an additive to orthodontic camouflage or a way to correct previous orthognathic surgery pitfalls. The surgeon performing esthetic genioplasty associated with gender-specific expectations must be trained in facelift and facial liposculpting techniques in order to provide the best results and properly choose the right procedures for the right patients.

Clinical application of V-shaped folded submental flap in the repair of oral defect. / Våž‹æŠ˜å é¢ä¸‹çš®ç“£ä¿®å¤å£è ”ç¼ºæŸçš„ä¸´åºŠåº”ç”¨.

OBJECTIVES: The repair of small and medium-sized defects in the oral has always been a challenge, free skin flap and distal pedicled tissue flaps are difficult to meet clinical needs, and the traditional under-chin flap has the risk of donor-area injury. This study aims to investigate the efficacy of V-shaped folded submental flap in the repair of small-sized and medium-sized oral defects. METHODS: The clinical data of 28 patients with oral defect lesions, who were hospitalized in the Department of Stomatology, Third Xiangya Hospital of Central South University from March 2019 to December 2022, were retrospectively analyzed. Patients were divided into a V-shaped folded group (17 cases) and a conventional group (11 cases) according to different surgical methods. The V-shaped folded group was treated with a V-shaped folded submental flap for postoperative soft tissue repair, while the conventional group was treated with a conventional submental flap for repair. The postoperative follow-up time was 6-48 months. The survival status, repair time, and repair effect of the 2 groups were compared. RESULTS: There was no significant difference in flap survival rate, flap size, flap preparation time, repair surgery time, and postoperative hospital stay between the 2 groups (all P>0.05). At 6 months after the surgery, the V-shaped folded group had no difficulty in raising the head or everting the lower lip, no "cat ear" deformity in the submental skin. Scars in the V-shaped folding group were hidden at the lower edge of the mandible. The wound aesthetics and functional scores in the V-shaped folded group were significantly higher than those in the conventional group (both P<0.05). CONCLUSIONS: The V-shaped foldable submental flap has the advantages of flexible design, simple preparation, reliable blood supply, and protection of the donor area, which can effectively protect the appearance of the chin and avoid functional disorders.

Genioplasty - A Review.

Genioplasty, a key technique for dentofacial abnormalities, is essential for establishing facial harmony. This surgical procedure entails an osteotomy of the chin, which alters its three-dimensional location to restore overall face equilibrium. Modern genioplasty, which is frequently performed alone or in combination with rhinoplasty, facelifts, and orthognathic surgery, employs a variety of materials for chin augmentation, ranging from autologous to alloplastic. Recent improvements include porous graft materials such as high-density polyethylene. Despite the need for secure osteotomy segments, soft tissues around the mandible have a natural propensity to return to their original anatomical position. In the discipline of genioplasty, face esthetics and facial evaluation have been a prominent emphasis, with historical evidence emphasizing the relevance of the chin in harmony, balance, and character perception. Customized implants provide a single therapy for rare anatomical defects, generally with lower morbidity, making them critical for patients undergoing many procedures or suffering from syndromic disorders. Virtual surgical planning advances will continue to give dependable solutions for small and complex chin position issues. Modern surgeons will continue to combine history, anatomy, rigorous evaluation, excellent execution, and technological breakthroughs to achieve the best possible outcomes for their patients, raising their social standing.

Aesthetic Concerns of Chin Augmentation With Hyaluronic Acid Soft Tissue Filler in Chinese: A Prospective, Observational Study.

BACKGROUND: The chin is an important facial structure that directly affects the overall contour of the face. The key to achieving a beautiful, effective, and safe chin injection is to make a good facial assessment and use an appropriate injection technique to achieve the best injection effect. OBJECTIVE: In this article, the authors will discuss cosmetic concepts for the chin area and verify the effectiveness of chin augmentation techniques. MATERIALS AND METHODS: Chin volume injections were performed on 23 Asian female subjects and 15 Asian male subjects. Demographic and imaging data were collected, and the facial aesthetic length was calculated. The authors also measured the length of beautiful chins, as evaluated by 2 plastic surgeons, and the ratios of chins from "The 100 Most Beautiful/Handsome Faces in China" published by TCC Asia in 2020. RESULTS: The mean volume of chin filling was 1.89 ± 0.74 mL in female subjects and 2.68 ± 1.28 mL in male subjects. The ideal length of the chin was equal to that of the nasal dorsum in male subjects, and the ideal chin-to-nasal dorsum ratio was 0.9 in female subjects. CONCLUSION: In this study, the authors investigate sex differences in chin aesthetics among the Chinese population and introduce an aesthetic and anatomical approach to chin injection.

Effectiveness of Autogenous Chin Bone Graft in Reconstructive Surgery of Cleft Patients: A Systematic Review With Meta-Analysis and Algorithm of Treatment.

PURPOSE: Bone grafting is fundamental in the treatment of cleft patients, and several grafting materials have been used for this purpose. The objective of this study is to evaluate the effectiveness of autogenous bone graft from the chin in the reconstruction of cleft alveolus. METHODS: Searches were performed in six databases (PubMed, Scopus, Cochrane, LILACS, Embase, and Google Scholar) by two researchers individually until July 2022. This study was registered in the International Prospective Register of Systematic Reviews (CRD42021267954) and conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The predictor variable is reconstruction technique, grouped into three levels: autogenous genial grafts, other endochondral autogenous grafts, and bio- or tissue-engineered materials. The outcome variables were alveolar cleft healing rate and bone height. The secondary variables were complications that included infections, necrosis, paresthesia, and dehiscence. Data analysis included the risk of bias and assessment of the certainty of evidence by the risk of bias in nonrandomized studies of interventions and grading of recommendations, assessment, development, and evaluation tools, respectively. The meta-analysis was performed with heterogeneity based on random effects of I2 and 95% confidence. RESULTS: In the initial search, 4,833 articles were found, and 10 of them were included in this systematic review. The included studies were from six countries on three different continents, with a sample of 692 patients. It was observed that the chin bone graft (214 patients) when compared to the endochondral bone graft (386 patients) reduced by 0.42 [confidence interval 95% = 0.18, 0.95] times the prevalence of bone resorption (P = .040 and I2 = 70%) analyzed in radiographic images. Two studies evaluated the bone filling through computed tomography, and there was no statistically significant difference between the groups (P = .340, I2 = 0%). Only two studies had a low risk of bias. CONCLUSION: Based on a low certainty of evidence, the chin autogenous bone graft proved to be similar to the endochondral graft in the reconstruction of the cleft alveolar; however, the limited number of studies with high heterogeneity and an uncertain risk of bias decreased the strength of the results found in this systematic review. New controlled primary studies should be carried out with the purpose of safely determining the effectiveness of chin bone grafts for the reconstruction of cleft alveolar.

Complications Following Alloplastic Chin Augmentation: A Systematic Review of Implant Materials and Surgical Techniques.

BACKGROUND: Alloplastic implantation has become a popular method of chin augmentation. Historically, silicone was the most commonly used implant, but porous materials have grown in favor due to improved fibrovascularization and stability. Nevertheless, it is unclear which implant type has the most favorable complication profile. This systematic review aims to compare the complications of published chin implants and surgical approaches to provide data-driven recommendations for optimizing chin augmentation outcomes. METHODS: The PubMed® database was queried on March 14, 2021. We selected studies reporting data on alloplastic chin augmentation excluding additional procedures such as osseous genioplasty, fat grafting, autologous grafting, and fillers. The following complications were extracted from each article: malposition, infection, extrusion, revision, removal, paresthesias, and asymmetry. RESULTS: Among the 39 articles analyzed, the year of publication ranged from 1982 to 2020; additionally, 31 were retrospective case series, 5 were retrospective cohort or comparative studies, 2 were case reports, and 1 was a prospective case series. More than 3104 patients were included. Among the 11 implants reported, the 3 implants with the highest number of publications were silicone, high-density porous polyethylene (HDPE), and expanded polytetrafluoroethylene (ePTFE). Silicone demonstrated the lowest rates of paresthesias (0.4%) compared to HDPE (20.1%, P < 0.01) and ePTFE (3.2%, P < 0.05). In contrast, there were no statistically significant differences in rates of implant malposition, infection, extrusion, revision, removal, or asymmetry when stratified by implant type. Various surgical approaches were also documented. Compared with subperiosteal implant placement, the dual-plane technique demonstrated higher rates of implant malposition (2.8% vs 0.5%, P < 0.04), revision (4.7% vs 1.0%, P < 0.001), and removal (4.7% vs 1.1%, P < 0.01), but a lower incidence of paresthesias (1.9% vs. 10.8%, P < 0.01). Compared with extraoral incisions, intraoral incisions resulted in higher rates of implant removal (1.5% vs 0.5%, P < 0.05) but lower rates of asymmetry (0.7% vs 7.5%, P < 0.01). CONCLUSION: Silicone, HDPE, and ePTFE had low overall complication rates, demonstrating an acceptable safety profile regardless of implant selection. Surgical approach was found to significantly influence complications. Additional comparative studies on surgical approach while controlling for implant type would be beneficial for optimizing alloplastic chin augmentation practices.

Reliability and Validity Evaluation of the Chin Augmentation With Medpor Using FACE-Q Scales Effectiveness.

BACKGROUND: Chin augmentation (CA) is important treatment modality for microgenia. The use of implantable alloplastic biomaterials in CA grows in popularity, and there is no verifiable documentation of patients' satisfaction about CA with Medpor (CAWM) exists in the literature, this study examined effectiveness of CAWM by analyzing patient satisfaction. METHODS: Patients had undergone CAWM were followed up postoperatively. Occurrence of complications was collected, patients' satisfactions with chin shape and surgical decision were analyzed using FACE-Q scales, the reliability of operation was studied through analyzing the statistics, and the influences of sex and follow-up time on satisfaction were compared. RESULTS: One hundred ten patients who had undergone CAWM received FACE-Q scales and 64 valid questionnaires were collected. 61 (95.3%) showed high satisfaction with chin shape after CAWM (Cronbach α coefficients were all above 0.8), the median values of satisfaction of chin shape and decision making were 85 (67, 100) and 100 (75,100), respectively. The median chin satisfactions of females and males were 87 (67, 100), 79 (61,100). The median chin satisfactions of patients had surgery before 2 years ago and within 2 years were 81 (67, 100), 87 (64,100), respectively. During the follow-up, among 110, 1 (0.91%) developed graft-related infection and 1 (0.91%) developed an allergic reaction, 1 (0.91%) underwent prosthesis removal because dissatisfaction with chin shape. CONCLUSIONS: Chin augmentation with prothesis is a safe and efficacious way to improve microgenia. Medpor is the desired implant material with less infection, displacement and bone absorption, which is worthy of promotion and further study in CA surgery.

Occlusal Plane Angle as a Key Factor for Chin Protrusion After Mandibular Osteotomy in Skeletal Class III.

There is no treatment algorithm to decide whether maxillomandibular or mandibular osteotomy alone should be performed in borderline cases. This study assessed the factors that affect the changes in soft tissue after mandibular setback. Patients who underwent mandibular osteotomy alone to correct mandibular protrusion were included in this study. Hard and soft tissue analyses were performed on lateral cephalograms before and 12±3 months after surgery. The popular points were set for referencing hard and soft tissues on the lateral cephalogram. Nasolabial, labiomental, and soft tissue facial plane angles were measured for the soft tissue assessment. To assess the mandibular setback amount, SNB was calculated. Twenty-one patients were included in this study. The nasolabial angle was increased after surgery and its change significantly correlated with the change in SNB ( P =0.00815). The change in soft tissue facial plane angle after surgery per change in SNB significantly correlated with the occlusal plane angle ( P =0.0009). An occlusal plane angle of at least 15.45 degrees was required for the SNB and soft tissue facial plane angle to change to the same degree. The occlusal plane angle (whether or not it was ≥15.45 degrees) may help in determining the surgical approach in borderline cases, specifically on whether maxillomandibular or mandibular osteotomy alone should be performed if the mandibular setback is simple.

Soft Tissue Chondroma of the Chin.

Soft tissue chondromas are benign tumors, generally of the hands or feet, very rarely of the head and neck region. Repeated microtrauma may be as an initiating factor. The authors describe a case of a soft tissue chondroma of the chin in a 58-year-old male who had used a continuous positive airway pressure face mask for obstructive sleep apnea for 3 years. The patient presented with a hard mass on his chin for 1 year. Computed tomography imaging showed a heterogeneous enhancing mass, with calcification in the subcutaneous layer. Intraoperatively, the mass was beneath the mentalis muscle and abutted the mental nerve, without bone involvement. The diagnosis was a soft tissue chondroma. The patient recovered fully, without recurrence. The primary cause of soft tissue chondromas is unknown. The authors consider that continuous use of a continuous positive airway pressure face mask may play a role in the etiology.

Simultaneous Mandibular Anterior Segmental Osteotomy and Genioplasty: A Novel Technique.

The current standard approach to treat class II malocclusion is orthodontic preparation followed by a mandibular advancement through bilateral sagittal split osteotomy associated or not with a genioplasty. However, when a malocclusion with an important incisors' axis deviation is associated with a chin malposition, an alternative technique can be considered: simultaneous mandibular anterior segmental osteotomy and genioplasty. This technique is performed without a bony bridge between osteotomies. Care must be taken not to wound the lingual mucosa. If preserved, this technique is safe. The result is stable and predictable.