Guided versus non-guided chin repositioning: a retrospective study on accuracy.

Genioplasty is a widely used surgical approach to address chin deformities by performing an osteotomy on the inferior border of the mandible to allow for comprehensive repositioning of the chin. This study aimed to compare the accuracy of freehand chin repositioning with a guided technique that employed specialised surgical guides. For this retrospective study, data from 30 adult patients who underwent orthognathic surgery to correct dentofacial deformities were analysed. All patients underwent virtual planning before surgery, with half of them treated using freehand chin repositioning and the other half using the guided technique. The surgical outcomes were measured and compared with the virtual plan to assess the positional and rotational accuracy of the techniques. In terms of translational assessment, noteworthy values that exceeded clinically acceptable limits were observed only in sagittal movement in the freehand group (0.97 mm, interquartile range (IQR) 0.73-2.29 mm). Regarding rotational accuracy, both groups exhibited an IQR that surpassed acceptable limits for pitch (3.26°, IQR 2.06-5.20 for the guided group and 2.57°, IQR 1.63-4.24° for the freehand group). The Mann-Whitney test indicated no statistical differences between the groups in any translational or rotational assessment. In conclusion, although there was no statistical difference, the guided technique proved effective in achieving clinically acceptable accuracy in all positions and almost all rotations, displaying superior results in sagittal positioning compared with the freehand technique. To fully harness the advantages of guides and to guarantee accuracy in all rotations, we recommend further research involving guides made of more rigid materials, and customised implants.

Comparison of Different Genioplasty Techniques in Terms of Neurosensory Deficit and Haematoma Formation.

OBJECTIVE: To compare different types of genioplasty techniques (chin advancement, rotation and advancement, setback, and reduction) in terms of neurosensory deficit and haematoma formation. STUDY DESIGN: Comparative analytical study. Place and Duration of the Study: Department of Oral and Maxillofacial Surgery, Armed Forces Institute of Dentistry, Rawalpindi, Pakistan, from January 2022 to April 2023. METHODOLOGY: Patients requiring genioplasty and fulfilling the inclusion criteria i.e. both genders aged 16-60 years were included and divided into 4 groups according to the type of genioplasty performed. Genioplasty was planned as per the ortho treatment plan and performed under general anaesthesia. Setback genioplasty was performed on 8 patients, advancement genioplasty on 11 patients, reduction genioplasty on 3, and advancement with rotation genioplasty on 16 patients. Postoperatively neurosensory deficit was recorded on follow-up after 1 month by subjective and objective assessments, and haematoma formation was assessed clinically on the 7th day after the procedure. RESULTS: Advancement with rotation genioplasty showed the highest frequency of neurosensory deficit (almost 50%) and reduction type genioplasty showed the least frequency of neurosensory deficit (<1%, p = 0.49). The frequency of haematoma formation was maximum in the advancement with rotation genioplasty (62.5%) and minimum in equal setback genioplasty (25%, p = 0.61). CONCLUSION: Advancement with rotation genioplasty had the highest rate of postoperative neurosensory deficit and haematoma formation when compared with other techniques of genioplasty. KEY WORDS: Genioplasty, Neurosensory deficit, Haematoma, Advancement with rotation genioplasty, Setback genioplasty.

Does the Implementation of Virtual Planning has a Significant Impact on Reducing the Revision Rate in Orthognathic Surgery?

PURPOSE: Conventional orthognathic surgical planning has limitations in accurately transferring the relationship between soft tissue and bone. Virtual planning offers enhanced accuracy and visualization through computer simulation. This study aimed to compare the need for reoperation between patients who underwent conventional and virtual surgical planning for orthognathic surgery. MATERIAL AND METHODS: The study included 352 patients who underwent orthognathic surgery. Reoperation rates and reasons for reoperation were evaluated in patients with conventional model surgery planning (143 patients) and virtual planning (209 patients). RESULTS: The reoperation rate was 7.69% for conventional surgery patients and 3.82% for virtual planning patients. Malocclusion was the most common reason for reoperation in both groups. Bilateral sagittal split ramus osteotomies (BSSO) and genioplasty were the most frequently performed revision procedures. CONCLUSION: Virtual planning in orthognathic surgery may lead to a reduced reoperation rate compared with conventional planning methods. The accuracy, visualization, and interdisciplinary collaboration offered by virtual planning can improve surgical outcomes.

Evaluation of soft tissue profile changes following autogenous fat or onlay PEEK augmentation versus sliding genioplasty for correction of deficient chin: Randomized controlled clinical trial.

AIM: The study was conducted to evaluate soft tissue profile changes using autogenous fat augmentation or onlay PEEK versus sliding genioplasty for correction of deficient chin in patients with retruded chin. MATERIAL AND METHODS: Thirty-three patients with deficient chins were included in the study. The patients were distributed into 3 groups: the fat augmentation group as intervention I, the PEEK augmentation group as intervention II, and the osseous genioplasty group as control group. Preoperative and postoperative CBCT were performed for all patients. With the aid of MIMICS,3-MATIC, and PROPLAN software, diagnosis, virtual planning, and evaluation were performed. The Face-Q questionnaire was used to assess patient satisfaction. RESULTS: There was a statistically significant difference regarding soft tissue relapse in the fat group after 6 months when compared to the control group (mean difference= 0.770), while there was no statistically significant difference regarding soft tissue relapse between PEEK and control group (mean difference= -0.060). Intragroup comparison has shown no statistically significant difference regarding soft tissue relapse within all groups between follow-up periods (P = 0.1389 for the fat group, P = 0.8739 for the peek group, and P = 0.8410 for the control group). All patients showed a statistically significant increase in scores of satisfaction with the chin between follow-up periods (P = 0.0165, P = 0.0150, and P = 0.0293) respectively. CONCLUSIONS: Fat augmentation can be a good intervention choice in mild-moderate deficient cases. PEEK PSI has a stable surgical outcome.

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 .

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.

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.

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 .

Accuracy of the CAD/CAM technique compared with the conventional technique used for stand-alone genioplasty.

The benefit of the computer-aided design and manufacturing (CAD/CAM) technique for stand-alone genioplasty remains uncertain and was evaluated in this study. Patients who underwent a conventional genioplasty (n = 20) or genioplasty with the CAD/CAM technique (n = 20), and for whom cephalometry and photogrammetry were performed before and 6 months after surgery, were included. Deviations from predictions of the soft tissue pogonion (Pg'), lip inferior point to aesthetic line (Li-Esth), facial convexity angle (FCA), mentolabial angle (MLA), and ratios of soft to hard tissue movements were calculated. No significant deviation was observed for Pg' in either the conventional group (3.85 ± 4.36 mm; 1.91 ± 1.11 mm) or CAD/CAM group (1.28 ± 1.16 mm; 2.81 ± 3.08 mm), for horizontal and vertical movements, respectively. However, for forward movement, deviation from the prediction of Pg´ in the CAD/CAM group was significantly lower than that in the conventional group (P = 0.015). Deviations of Li-Esth, MLA, and FCA did not differ significantly between the groups. No definite preference for the CAD/CAM technique could be established, because deviations from predictions were not significant in either of the technique groups and lay within the clinically acceptable range.

Validation of a fully automatic three-dimensional assessment of orthognathic surgery.

The aim of the present study was to propose and validate FAST3D: a fully automatic three-dimensional (3D) assessment of the surgical accuracy and the long-term skeletal stability of orthognathic surgery. To validate FAST3D, the agreement between FAST3D and a validated state-of-the-art semi-automatic method was calculated by intra-class correlation coefficients (ICC) at a 95 % confidence interval. A one-sided hypothesis test was performed to evaluate whether the absolute discrepancy between the measurements produced by the two methods was statistically significantly below a clinically relevant error margin of 0.5 mm. Ten subjects (six male, four female; mean age 24.4 years), class II and III, who underwent a combined three-piece Le Fort I osteotomy, bilateral sagittal split osteotomy and genioplasty, were included in the validation study. The agreement between the two methods was excellent for all measurements, ICC range (0.85-1.00), and fair for the rotational stability of the chin, ICC = 0.54. The absolute discrepancy for all measurements was statistically significantly lower than the clinical relevant error margin (p < 0.008). Within the limitations of the present validation study, FAST3D demonstrated to be reliable and may be adopted whenever appropriate in order to reduce the work load of the medical staff.

Preoperative Radiology and Virtual Surgical Planning.

Virtual surgical planning enables precise surgical planning and translation of this planning into the operating room. Preoperative maxillofacial computed tomography scans are compared to a reference skull to identify desired surgical changes. In facial feminization surgery, these include forehead recontouring/frontal table setback, gonial angle reduction, and possible chin repositioning/reshaping, while in facial masculinization surgery, this includes forehead augmentation and gonial angle/chin augmentation. Cutting and recontouring guides as well as custom implants are then custom manufactured. Common guides include osteotomy guides, depth drilling guides, ostectomy guides, and guides for one/two-piece genioplasty or chin burring. Common implants include mandibular and chin implants.

What is the angular accuracy of regional voxel-based registration for segmental Le Fort I and genioplasty osteotomies?

Among the accuracy analysis techniques for orthognathic surgery, regional voxel-based registration (R-VBR) has robust data, but remains unvalidated for smaller jaw segments. The purpose of this study was to validate the angular accuracy of R-VBR for segmental Le Fort I (SLFI) and genioplasty osteotomies. Postoperative cone beam computed tomography (CBCT) of consecutive patients with three-piece SLFI or genioplasties was rotated to a known pitch/roll/yaw (P/R/Y). Using R-VBR, a copy of the raw CBCT was superimposed onto the rotated CBCT at four mutual regions of interest (ROI): anterior, right posterior, and left posterior maxilla, and chin. The P/R/Y of each was subtracted from those of the rotated CBCT to calculate the angular error. The predictor and outcome variables were ROI and absolute angular error, respectively. The accuracy threshold was 0.5°. Ten SLFI and 34 genioplasties were analyzed based on the sample size calculation. The one-sample t-test and Wilcoxon signed rank test were applied in the analysis. The mean absolute error was 0.20-0.54° for the maxillary segments (all P ≤ 0.01) and 0.83-2.51° for the genioplasty segments (all P < 0.001). R-VBR has variable angular accuracy for SLFI osteotomies and may be insufficient for genioplasty. The findings may allow the design and interpretation of studies on SLFI and genioplasty with greater rigor, thereby contributing to minimizing the discrepancy between planned and achieved outcomes.

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.

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.

Single-Step Full-Face Surgical Treatment of the Facial Profile.

The present study was performed to describe how much affordable, feasible, and straightforward is the approach the authors called "single-stage full-face surgical profileplasty," tailored to greatly improve the surgery of the facial profiling setting and achieve complete profile correction at the same time. From January 2010 to May 2019, 113 patients (95 females and 18 males; aged 19 - 63 years) were surgically treated for full-face profile amelioration. Profile correction was performed by using a combination of five procedures out of other various previously experienced: forehead fat grafting, rhinoplasty, lip fat grafting, genioplasty, and submental liposuction. All patients were assessed at 1, 3, 6, and 12 months following surgery for assessing the surgical profile treatment (SPT) outcome and any possible side effects of the combined treatment. Facial profile stability at 1 year was taken as the completion point of this treatment. Arnett et al's "Soft Tissue Cephalometric Analysis" (1999) was used to clinically evaluate the soft tissues before and after the SPT. Patients' satisfaction was measured with the Client Satisfaction Questionnaire-8" at 3 and 12 months after surgery. Statistics were used for Arnett et al's evaluation. Almost all the values were consistent and reached the normal ranges indicated by Arnett et al (p < 0.001), confirming that the desired results of the surgical profileplasty have been achieved. Single-stage full-face surgical profile treatment helps in correcting faults of the global facial deformity, in every single treated area, providing an overall improvement in facial aesthetics and harmony. Obtaining the simultaneous correction in the whole face has also the advantage of avoiding multiple surgical procedures, reducing postoperative discomfort, and the overall risks for the patient due to multiple surgical and anesthetic procedures.

Osseous genioplasty versus chin implants: early complications and patient satisfaction.

Osseous genioplasty and chin augmentation with implants are the two main treatment options for retrognathia. This retrospective cohort study was performed to compare the prevalence of complications and patient satisfaction following osseous genioplasty and chin augmentation by implant. Eighty patients were included: 38 underwent advancement osseous genioplasty and 42 received chin implants (alloplastic, either Medpor or Silastic) intraorally or extraorally. The patients were assessed for complications 12 months after surgery, including neurosensory disturbances, infection or extrusion, wound dehiscence, and the need for reoperation. Patient satisfaction was evaluated using a visual analogue scale. The infection rate was significantly higher in the chin implant group than in the genioplasty group (P = 0.028). Moreover, dehiscence and the need for reoperation appeared to be more common following chin augmentation with implants. However, there was no significant difference in the prevalence of neurosensory disturbances between the two groups (P = 0.137). In the chin implants group, the extraoral approach resulted in a lower dehiscence rate than the intraoral approach. Patients in the genioplasty group had significantly higher satisfaction scores than those in the chin implant group (P = 0.001). Overall, the rates of the complications assessed were lower and patient satisfaction was higher after osseous genioplasty when compared to chin augmentation with implants.

Soft-Tissue Response following Genioplasty Combined with Anterior Segmental Osteotomy.

BACKGROUND: The authors' main aim was to analyze soft-tissue response of the chin following genioplasty with anterior segmental osteotomy, which enables optimal surgical planning of genioplasty. METHODS: Sixty-two patients who underwent genioplasty with concomitant anterior segmental osteotomy were divided into three groups depending on the direction of pogonion (Pog) movement: G1 (without sagittal change), G2 (advancement genioplasty), and G3 (setback genioplasty). All genioplasties included height reduction. Hard- and soft-tissue measurements with cephalometry were performed at T1 (before surgery), T2 (after surgery), and T3 (after orthodontic treatment) for the analysis of sagittal and vertical changes. Correlation and regression analyses were conducted to analyze soft- to hard -tissue movement and soft-tissue thickness changes. RESULTS: During the T1 to T2 period, the horizontal soft- to hard-tissue ratio at Pog was 0.85 in G2 and 0.80 in G3, and the vertical ratio at menton (Me) was 0.9 for all groups. The correlation coefficients were 0.64 (G2) and 0.83 (G3) at Pog and 0.9 (all), 0.85 (G1), 0.95 (G3) at Me. There was no significant correlation between initial soft-tissue thickness and soft-tissue response ratio. During the T2 to T3 period, no significant relapses were observed, which demonstrates the stability of anterior segmental osteotomy combined genioplasty. CONCLUSIONS: Clinically and statistically significant soft-tissue responses were demonstrated at Pog and Me. The higher values in G3 in particular suggest that setback genioplasty with anterior segmental osteotomy is an effective treatment alternative to conventional two-jaw surgery in some patients with bimaxillary prognathism with macrogenia. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

[Three-dimensional comparative study on the stability of bimaxillary simultaneous genioplasty and simple genioplasty].

PURPOSE: To establish a three-dimensional method to evaluate whether there is a difference in stability between bimaxillary simultaneous genioplasty and simple genioplasty. METHODS: This study was a retrospective study. Sixty patients who underwent genioplasty were selected. They were divided into bimaxillary simultaneous genioplasty group (n=30) and simple genioplasty group (n=30). The spiral CT data of patients at 2 months before operation (T0), 7 days after operation (T1) and 12 months after operation (T2) were collected, reconstructed and separated, and the three-dimensional model of maxilla and mandible was obtained. A three-dimensional analysis method of stability was established by 3D-matching. Recurrences in three-dimensional space 12 months after surgery were analyzed in two groups of patients. Statistical analysis of the data was performed with SPSS 26.0 software package. RESULTS: In simple genioplasty, the maximum amount of the chin recurrence was sagittal backward recurrence (0.54±0.38) mm, and the sagittal recurrence rate was 12.27%. In bimaxillary simultaneous genioplasty, the maximum amount of the chin recurrence was sagittal backward recurrence (0.60±0.31) mm, and the sagittal recurrence rate was 12.96%. Rotation occurred in both groups 12 months after operation, which was 1.98±2.70° in the simple genioplasty group and 1.01±1.61° in the bimaxillary simultaneous genioplasty group(P＜0.05). There was no significant difference in the sagittal movement of the chin between the two groups, and in the sagittal recurrence(P＞0.05). CONCLUSIONS: The three-dimensional method established in this study can be used to evaluate the stability after genioplasty. The recurrence after genioplasty mainly occurred in the sagittal direction. The rotation trend of chin after genioplasty is worthy of attention. There was no increased risk for bimaxillary simultaneous genioplasty.

[Surgical treatment of a patient with mandibular micrognathia accompanied by obstructive sleep apnea syndrome using extended genioplasty]. / Khirurgicheskoe lechenie patsienta s mikrognatiei nizhnei chelyusti i sindromom obstruktivnogo apnoe vo sne metodom rasshirennoi genioplastiki.

A method for diagnosing, planning and surgical treatment of patients with micrognathia of the mandible with physiological occlusion is proposed, which makes it possible to objectively assess the severity of the anomaly and concomitant functional disorders of external respiration in the nasopharynx and oropharynx, as well as to identify the pathophysiological mechanisms of obstructive sleep apnea syndrome (OSAS) and develop an optimal surgical treatment plan with high functional and aesthetic results.

Stability of box genioplasty: a retrospective study.

In box genioplasty it is possible to advance, retrude, impact, and elongate, as well as to correct asymmetry. The aim of this study was to analyse the stability of box genioplasty as part of orthognathic correction. Twenty-five consecutive patients who had gone through the multidisciplinary pathway were selected. Menton and pogonion positions on radiographs taken just prior to surgery, and actual surgical movement on three-week and 12-month postoperative cephalograms, were compared. A one-sample Wilcoxon test was applied to assess whether the distributional change in advancement and vertical measurements was equal to zero. After treatment, anteroposterior changes in pogonion and vertical changes in menton were statistically insignificant (p>0.05). Our study demonstrated statistically significant stability of menton and pogonion positions after box genioplasty when surgical movement was only in the symphysis.