RESUMEN
BACKGROUND: Segmental mandibulectomy and reconstruction of resulting defect can be performed via intraoral approach (IOA) or extraoral approach (EOA). Both approaches have advantages, disadvantages, indications, and contraindications to consider during their selection. OBJECTIVE: To compare IOA vs EOA of segmental mandibulectomy and microvascular reconstruction with fibula free flap (FFF). METHODS: We conducted a retrospective cohort study in which 51 patients who underwent segmental mandibulectomy and microvascular reconstruction with FFF from 2020 to 2024 were included, especially 17 patients by IOA and 34 patients by EOA, representing both groups of this study. Clinical characteristics, surgery parameters, and patients' prognosis were evaluated. Patients' satisfaction and Derriford Appearance Scale (DAS59) were assessed during follow-up. RESULTS: Ameloblastoma was the most frequent diagnosis (52.9% managed by IOA vs 70.6% by EOA); FFF was frequently positioned as double barrel (94.1% managed by IOA vs 88.2% by EOA). Compared with EOA group, IOA group had less intraoperative blood loss (mean difference [MD] = -112.2, 95% confidence interval [CI]: -178.9 to -45.5, p = 0.001), higher satisfaction score (MD = 1.3, 95% CI: 0.9 to 1.7, p Ë 0.001), and lower DAS59 score (MD = -0.5, 95% CI: -0.7 to -0.2, p Ë 0.001). CONCLUSION: Both IOA and EOA were found safe and feasible, presenting similar perioperative features and postoperative outcomes. Patients managed with IOA were more satisfied with aesthetic outcomes than patients managed with EOA. In the absence of simultaneous immediate implant during mandibular FFF reconstruction, after stability of FFF on the defect site, patients should always be referred to an implantologist and/or prosthodontist for teeth restoration to improve functional and aesthetic outcomes.
Asunto(s)
Peroné , Colgajos Tisulares Libres , Osteotomía Mandibular , Satisfacción del Paciente , Humanos , Colgajos Tisulares Libres/irrigación sanguínea , Colgajos Tisulares Libres/trasplante , Masculino , Femenino , Estudios Retrospectivos , Osteotomía Mandibular/métodos , Persona de Mediana Edad , Peroné/trasplante , Peroné/irrigación sanguínea , Adulto , Procedimientos de Cirugía Plástica/métodos , Neoplasias Mandibulares/cirugía , Anciano , Ameloblastoma/cirugía , Mandíbula/cirugía , Reconstrucción Mandibular/métodosRESUMEN
A calcifying epithelial odontogenic tumor is a rare, benign odontogenic neoplasm. Surgical treatment is the option, and late recurrence is very rare. Radiologically, the lesions are commonly present scattered calcifications. This case report details a 64-year-old female patient with a recurrence of a right mandibular calcifying epithelial odontogenic tumor 2 decades after successful initial surgical removal. A segmental mandibulectomy and immediate reconstruction were performed using a planned vascularized free fibula flap with virtual surgery, custom reconstruction plate, and intraoperative computed tomography. Modifications were made to the design of the reconstruction plate to improve the cervicofacial profile and subsequent rehabilitation with dental implants. Fully guided implant surgery with point-of-care manufacturing protocol was done to improve prosthetically driven implant planning. The case presented highlights the usefulness of new technologies for mandibular reconstruction with the free fibula flap and the concept of point-of-care with technical notes that increase precision and reduce morbidity in implant-supported rehabilitation.
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Colgajos Tisulares Libres , Neoplasias Mandibulares , Recurrencia Local de Neoplasia , Tumores Odontogénicos , Humanos , Femenino , Persona de Mediana Edad , Tumores Odontogénicos/cirugía , Tumores Odontogénicos/patología , Tumores Odontogénicos/diagnóstico por imagen , Recurrencia Local de Neoplasia/cirugía , Neoplasias Mandibulares/cirugía , Neoplasias Mandibulares/diagnóstico por imagen , Neoplasias Mandibulares/patología , Tomografía Computarizada por Rayos X , Reconstrucción Mandibular/métodos , Peroné/trasplante , Peroné/cirugía , Placas Óseas , Cirugía Asistida por Computador/métodos , Osteotomía Mandibular/métodos , Neoplasias CutáneasRESUMEN
OBJECTIVE: The purpose of this study was to quantify the spontaneous new bone formation and bony bridge formation by 3-dimensional analysis of cone-beam computed tomography (CBCT) after segmental mandibulectomy reconstruction using an R-plate without any graft material in patients with medication-related osteonecrosis of the jaw (MRONJ). STUDY DESIGN: 15 MRONJ patients (13 females and 2 males) were selected based on the inclusion criteria. Data on new bone formation, bony bridge formation, R-plate fracture, patient age, and type and duration of medication were collected. Panoramic and CBCT scans were obtained at 1 day, 6, 12, and 24 months postoperatively. CBCT images of each period were transferred to a personal computer using MIMICS 21.0 for volumetric analysis. After quantifying the volume of new bone formation, we calculated the percentage of the volume of new bone to the segmentally resected necrotic bone volume (%NB). RESULTS: All patients showed spontaneous new bone formation with the average of 20.69% within a year and 28.52% within 2 years, and 80.0% showed bony bridge formation within a year. CONCLUSIONS: The R-plate reconstruction in patients with MRONJ showed significant amount of spontaneous new bone formation within 2 years after segmental mandibulectomy.
Asunto(s)
Tomografía Computarizada de Haz Cónico , Osteotomía Mandibular , Radiografía Panorámica , Humanos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Osteotomía Mandibular/métodos , Imagenología Tridimensional , Osteonecrosis de los Maxilares Asociada a Difosfonatos/diagnóstico por imagen , Osteonecrosis de los Maxilares Asociada a Difosfonatos/cirugía , Resultado del Tratamiento , Adulto , Placas Óseas , Osteogénesis/efectos de los fármacos , Mandíbula/cirugía , Mandíbula/diagnóstico por imagenRESUMEN
There are several treatment options to treat a class II dentofacial deformity with a pronounced chin. A total subapical osteotomy is one of these options. This type of osteotomy was refined to total subapical and ramus (TSAR) osteotomy. In this technical note, a detailed and schematic presentation of the TSAR osteotomy is presented step by step. The surgical approach to the TSAR osteotomy is divided into three parts. The first part consists of the horizontal osteotomy at the level of the ramus, the second part approaches the corticotomy to release and protect the mental nerve and the third part consists of connecting the horizontal ramus osteotomy and the local corticotomy around the mental nerve. In this third part, it is important that the inferior alveolar nerve (IAN) is actively sought and protected.
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Maloclusión Clase II de Angle , Humanos , Maloclusión Clase II de Angle/cirugía , Osteotomía Mandibular/métodos , Mandíbula/cirugía , Nervio Mandibular/cirugía , Mentón/cirugía , Osteotomía/métodos , Osteotomía Sagital de Rama Mandibular/métodosRESUMEN
For radical treatment of malignancies in the posterior region of the oral cavity and oropharynx, surgical exposure of the tumor by mandibulotomy is often required. Midline or paramedian vertical mandibulotomies are commonly performed in clinical practice, but these can damage the suprahyoid musculature and genioglossus, and weaken the swallowing and speech function of patients. Stair-stepped mandibulotomy is a new procedure, developed on the principles of functional surgery, that preserves the structure and function of the mandible whilst providing a clear field and avoiding damage to critical muscle attachments. Stair-stepped mandibulotomy is suitable for patients whose primary tumor is located in the middle and posterior part of the tongue or oropharynx, especially if the lesion involves extrinsic tongue muscles. In this case report, we draw on 2 cases of typical patients in our center to elaborate the surgery program design, operation points, advantages and disadvantages of stair-stepped mandibulotomy.
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Osteotomía Mandibular , Humanos , Osteotomía Mandibular/métodos , Masculino , Neoplasias Orofaríngeas/cirugía , Neoplasias Orofaríngeas/patología , Neoplasias de la Lengua/cirugía , Persona de Mediana Edad , Femenino , Mandíbula/cirugía , Carcinoma de Células Escamosas/cirugía , Carcinoma de Células Escamosas/patología , AncianoRESUMEN
PURPOSE: This study aims to evaluate the factors most associated with early and late complications following microvascular free tissue transfer (MVFTT) after mandibulectomy. METHODS: A retrospective review of patients undergoing MVFTT after segmental mandibulectomy from September 2016 to February 2021 was performed across a single academic institution. Surgical variables were collected, including the location of the resultant mandibular defect (anterior vs posterior) and flap type (osseous or non-osseous). The primary outcome variables included postoperative complications (early, <90 days; and late, >90 days) and the patients' functional status (return to oral intake). Descriptive statistics, chi-square test, Fischer's exact test, and 2-sample t tests were used to analyze differences among variables. RESULTS: We analyzed a cohort of 114 consecutive patients with mandibular defects, comprising 57 anterior and 57 posterior defects. Bony free flaps with hardware were used to reconstruct 98% of anterior defects compared to 58% of posterior defects (P < .001). All soft tissue only flaps did not utilize any hardware during the reconstruction. Anterior defects demonstrated more late complications requiring additional surgery (30% vs 9%, P = .04). A secondary analysis of posterior mandibular reconstructions compared soft tissue only flaps and bony free flaps with hardware and showed equivalent rates of early (12% vs 13%, P > .99) and late (9% vs 8%, P > .99) complications requiring additional surgery while demonstrating a similar return to full oral competence (55% vs 46%, P = .52) and recovery of a 100% oral diet (67% vs 54%, P = .53). CONCLUSION: Osseous free tissue transfer for segmental mandibular defects remains the gold standard in reconstruction. In our patient cohort, anterior mandibular defects are associated with greater late (>90 day) complications requiring additional surgery. Comparable outcomes may be achieved with soft tissue only versus osseous free flap reconstruction of posterior mandibular defects.
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Colgajos Tisulares Libres , Osteotomía Mandibular , Reconstrucción Mandibular , Complicaciones Posoperatorias , Humanos , Masculino , Estudios Retrospectivos , Femenino , Persona de Mediana Edad , Osteotomía Mandibular/métodos , Complicaciones Posoperatorias/prevención & control , Anciano , Reconstrucción Mandibular/métodos , Adulto , Neoplasias Mandibulares/cirugía , Mandíbula/cirugía , Procedimientos de Cirugía Plástica/métodosRESUMEN
BACKGROUND: The adequacy of the cut end of the mandible following a segmental mandibulectomy done for oral cancer intraoperatively is at times assessed using a frozen section (FS) of the bone marrow (BM) at the cut ends. The study aimed to assess its utility to guide the intraoperative decision on the adequacy of bony margins. MATERIALS AND METHODS: All patients with oral squamous cell carcinoma (OSCC) who underwent segmental mandibulectomy from January 2012 to December 2021 at our institute and for whom intraoperative FS of BM was utilized were included. We analyzed the sensitivity, specificity, and positive and negative predictive value (PPV, NPV) of this in predicting positive bone margins. RESULTS: A total of 457 patients were included in the study. The majority of the cases were per premium cases (n = 372, 81.4%). The median age of the cohort was 52 years (range: 22-80 years). Most patients had T4 disease (n = 406, 88.8%). On FS, BM was positive in only 18 patients (3.9%) for whom the bone margin was revised. BM biopsy report in the final histopathology was positive in 12 patients (2.2%). The sensitivity, specificity PPV, and NPV were 52.3%, 98.65%, 64.7%, and 97.7% respectively. No factors predicting BM positivity on FS could be identified in this cohort. CONCLUSIONS: The BM FS was positive in only a small percentage of patients, and it helped in reducing the bone margin positivity rate from 3.9% to 2.2% only. Hence the intraoperative BM FS seems to have limited utility as seen from our study.
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Médula Ósea , Secciones por Congelación , Mandíbula , Osteotomía Mandibular , Márgenes de Escisión , Neoplasias de la Boca , Humanos , Persona de Mediana Edad , Masculino , Femenino , Anciano , Neoplasias de la Boca/cirugía , Neoplasias de la Boca/patología , Adulto , Anciano de 80 o más Años , Osteotomía Mandibular/métodos , Mandíbula/cirugía , Mandíbula/patología , Médula Ósea/patología , Adulto Joven , Estudios Retrospectivos , Carcinoma de Células Escamosas/cirugía , Carcinoma de Células Escamosas/patología , Estudios de Seguimiento , PronósticoRESUMEN
This study presents a combination of 2 different surgery procedures performed on the mandible as part of the treatment aiming to improve the facial profile and occlusal function of patients with severe skeletal class â ¢ malocclusion and bilateral edentulous gaps. The teeth next to the edentulous gaps were found to be ankylosed. Mandibular setback by bilateral sagittal split ramus osteotomies and mandibular body osteotomies, combined with Le Fort â level maxillary advancement were performed, since the chief complaint of the patient was a concave profile. As a result, the skeletal class â ¢ malocclusion had been corrected, a satisfying facial profile had been achieved, and no apparent adverse effect was found. Thus, it has been proved that the combination of sagittal split ramus osteotomy and mandibular body osteotomy is available for correcting skeletal class â ¢ malocclusion.
Asunto(s)
Maloclusión de Angle Clase III , Osteotomía Sagital de Rama Mandibular , Anquilosis del Diente , Adulto , Humanos , Cefalometría , Maloclusión de Angle Clase III/cirugía , Mandíbula/cirugía , Osteotomía Mandibular/métodos , Osteotomía Le Fort/métodos , Osteotomía Sagital de Rama Mandibular/métodos , Anquilosis del Diente/cirugíaRESUMEN
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 .
Asunto(s)
Osteotomía Mandibular , Humanos , Estudios Retrospectivos , Femenino , Masculino , Osteotomía Mandibular/métodos , Adulto , Mentón/cirugía , Adulto Joven , Músculos del Cuello/cirugía , Músculos del Cuello/diagnóstico por imagen , Estética , Estudios de Cohortes , Mandíbula/cirugía , Mandíbula/diagnóstico por imagen , Estudios de Seguimiento , Tomografía Computarizada por Rayos X/métodos , Osteotomía/métodosRESUMEN
BACKGROUND: The current absence of a standardized mandibular body osteotomy design poses challenges in surgical planning. Traditional approaches may not suit patients with wider anterior mandibles, potentially resulting in unsatisfactory outcomes. Addressing this issue requires a rational design that combines mandibular angle and body osteotomies for improved clinical practice. OBJECTIVES: In this retrospective cohort study we aimed to analyze mandibular computed tomography (CT) data with digital methods. The goal was to establish an integrated osteotomy design for both mandibular angle and body procedures and classify prevalent mandibular types in the Chinese Han population for surgical guidance. METHODS: Included were 89 patients who underwent mandibular angle osteotomy without genioplasty between 2016 and 2022 at Peking University Third Hospital. Mimics 21.0 software facilitated CT data reconstruction and osteotomy planning. Postoperative effects were assessed through imaging, complications, and surveys, leading to mandibular type classification. RESULTS: Mandibular angles were categorized by 3 types, based on osteotomy range. Type I involved mandibular body osteotomy only, type II mandibular angle osteotomy only, and type III both mandibular angle and body osteotomies. Distribution within the cohort was 2.25%, 8.99%, and 88.76% for types I, II, and III respectively. Patient satisfaction was high, with minor and major complications at 47.19% and 1.12% by Clavien-Dindo classification. CONCLUSIONS: Utilizing Mimics software, we established an integrated osteotomy design and categorized mandibular types. Findings offer valuable guidance for mandibular angle surgery and contribute to understanding of Asian mandibular morphology.
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Mandíbula , Osteotomía Mandibular , Humanos , Estudios Retrospectivos , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Osteotomía Mandibular/métodos , Estética , ChinaRESUMEN
BACKGROUND: Reconstruction of continuity defects following osteonecrosis in multimorbid patients is challenging. In all cases of the predescribed palliative treatment method for alloplastic mandible reconstruction, plate fractures were detected in follow-up. We hypothesized that a modification could avoid these fractures, leading to stable long-term results. METHODS: This retrospective study compares the original method with a modification using single, laser-sintered CAD-CAM plates instead of manually bent miniplates. The predescribed shuttering technique was used to reconstruct the mandible in its original shape with bone cement. RESULTS: Uneventful wound healing was observed in 86% of the cases after modification of the method. No implant or plate fracture occurred. CONCLUSIONS: The presented method should be considered as a treatment option for mandible reconstruction in elderly, multimorbid patients in palliative situations. The results of this study suggest that the modification of the method leads to significantly improved long-term stability. Donor site morbidity is avoided with this method of palliative surgery.
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Osteonecrosis de los Maxilares Asociada a Difosfonatos , Reconstrucción Mandibular , Osteonecrosis , Humanos , Anciano , Osteotomía Mandibular/métodos , Estudios Retrospectivos , Mandíbula/cirugía , Osteonecrosis/cirugía , Reconstrucción Mandibular/métodos , Osteonecrosis de los Maxilares Asociada a Difosfonatos/cirugíaRESUMEN
With the advancement of digital technology over the last few decades, the use of virtual surgical planning and fabrication of surgical guides have tremendously improved the outcomes of various maxillofacial surgical procedures. The intraoral vertical ramus osteotomy (IVRO) is an orthognathic surgical procedure largely employed for mandibular setback in correcting dentofacial deformities. This study describes the design and application of a surgical cutting guide for IVRO. The guide can also be used to facilitate the placement of miniplate fixation. The initial experience at the authors' centre suggests that the guide has allowed the osteotomy to be performed with increased precision and confidence. Furthermore, the use of miniplate fixation decreased the period of maxillomandibular fixation. However, a larger series is required to evaluate the utility of this system more thoroughly.
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Procedimientos Quirúrgicos Ortognáticos , Prognatismo , Humanos , Osteotomía Sagital de Rama Mandibular/métodos , Prognatismo/cirugía , Mandíbula/cirugía , Placas Óseas , Osteotomía Mandibular/métodosRESUMEN
BACKGROUND: Mandibular angle osteotomy (MAO) is a frequently described technique in Eastern females. The success hinges on the precise positioning of the osteotomy line. The geometric mathematical method is viable. Therefore, we explored the impact of mandibular angle osteotomy using aesthetic standards and printed digital osteotomy templates (DOTs) on the aesthetic osteotomy line. METHODS: This retrospective observational study included female patients with prominent mandibular angle (PMA) who underwent MAO at our hospital between January 2020 and March 2021. Thirty-three female patients were included, 22 in the DOTs group using new DOTs, and 11 in the traditional group using traditional free-hand techniques. RESULTS: Regarding the width of the excised bone, the postoperative deviation from the preoperative plan was not significant in the DOTs group (0.5 ± 0.3 mm, P > 0.05), while the deviation was significant for the traditional group (2.5 ± 1.2 mm, P<0.05). The preparation time was longer in the DOTs group than in the traditional group (82 ± 11 vs. 53±4 min, P < 0.001). The osteotomy time and the operation time were shorter in the DOTs group than in the traditional group (osteotomy: 54 ± 5 vs. 73 ± 6 min; preparation: 124 ± 10 vs. 169 ± 13 min; both P < 0.001). The Likert (4.0 ± 0.5 vs. 1.0 ± 0.6, P = 0.006) and FACE-Q scores (17.5 ± 1.7 vs. 15.6 ± 1.3, P = 0.029) were higher in the DOTs group. CONCLUSIONS: The new method of positioning the new aesthetic osteotomy line based on geometric analysis might provide a possible osteotomy method that strongly suggests effectiveness, safety, individualization, and accuracy, with a shorter operation and higher patient satisfaction. 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 .
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Osteotomía Mandibular , Osteotomía , Humanos , Femenino , Resultado del Tratamiento , Osteotomía Mandibular/métodos , Osteotomía/métodos , Estudios Retrospectivos , Estética , MonoaminooxidasaRESUMEN
Porcine mandibular defect models are commonly used for the preclinical evaluation of reconstruction techniques. Existing studies vary in technique, complexity, and postoperative outcomes. The procedures are complex and often described without sufficient detail. We describe in detail a simple and reproducible method for creating a critical-size mandibular defect in a porcine model. Seven hemimandibular critical size defects were created in five male Yorkshire-Landrace pigs, three with unilateral defects and two with bilateral defects. A transverse incision was made over the mandibular body. Periosteum was incised and elevated to expose the mandibular body and a critical-size defect of 30 × 20 mm created using an oscillating saw. The implant was inserted and fixed with a titanium reconstruction plate and bicortical locking screws, and the wound closed in layers with resorbable sutures. Intraoral contamination was avoided. Dentition was retained and the mental nerve and its branches preserved. The marginal mandibular nerve was not encountered during dissection. All pigs retained normal masticatory function, and there were no cases of infection, wound breakdown, haematoma, salivary leak, or implant-related complications. The procedure can be performed bilaterally on both hemimandibles without affecting load-bearing function. All pigs survived until the end point of three months. Postoperative computed tomographic scans and histology showed new bone formation, and a three-point bend test showed the restoration of biomechanical strength. Straight-segment mandibulectomy is a simple and reproducible method for the creation of critical-size mandibular defects in a porcine model, simulating a load-bearing situation.
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Mandíbula , Osteotomía Mandibular , Reconstrucción Mandibular , Animales , Masculino , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Osteotomía Mandibular/métodos , Osteotomía Mandibular/normas , Periostio/cirugía , Porcinos , Tomografía Computarizada por Rayos X , Modelos Animales , Prótesis Anclada al Hueso/normas , TitanioRESUMEN
BACKGROUND: In east Asia, lower face contouring surgeries including reduction mandibuloplasty and genioplasty are the most popular aesthetic craniofacial surgeries. Conventional selection of surgical strategies mainly relied on the visual judgment of the mandibular angle, without overall assessment of the mandibular sub-units. Furthermore, only a few studies offered quantitative assessment of the mandibular shape. METHODS: From 2010 to 2021, 1241 patients diagnosed with square faces and received customized lower face contouring surgeries by the senior author were reviewed and analyzed to propose an "ABC" classification system for facilitating surgical planning. RESULTS: Among them, 998 (80.42%) received bilateral mandible reshaping, 155 (12.49%) underwent bilateral mandible reshaping combined with genioplasty, and 88 (7.09%) received asymmetric mandible reshaping. A modified classification system composed of three critical parameters (height, morphology/thickness, divergence) in three aesthetic zones (mandibular angle, mandibular body, chin) was proposed based on quantitative summarization of the CT database and the senior author's 12-year experience. The way to facilitate surgical planning with this classification was demonstrated. CONCLUSIONS: This modified classification system ushered a decision-making process that prioritized several critical measurements and proposed an operative planning form. Meanwhile, it can also be cooperated into the three-dimensional virtual surgical plan. 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 http://www.springer.com/00266 .
Asunto(s)
Mandíbula , Osteotomía Mandibular , Humanos , Resultado del Tratamiento , Estudios Retrospectivos , Mandíbula/cirugía , Osteotomía Mandibular/métodos , Mentoplastia/métodosRESUMEN
ABSTRACT: This study presents an innovative surgery that successfully improved the facial profile and occlusal function of a patient with a skeletal Class III malocclusion and posterior hypodontia. The patient had chief complaints of missing teeth and a protrudedjaw. A novel 1-stage surgery referred to as posterior mandibular segmental split osteotomy combined with Le Fort i osteotomy and BSSRO was used because the patient wanted to save time and was worried about periodontal complications associated with other treatment methods. As a result, a satisfying facial profile and a Class I occlusion with a normal position of the posterior dentoalveolar segment of the mandible were achieved with no adverse effects. Thus, posterior mandibular segmental split osteotomy can be considered an effective treatment for skeletal Class III malocclusion with posterior hypodontia.
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Anodoncia , Maloclusión de Angle Clase III , Cefalometría/métodos , Humanos , Maloclusión de Angle Clase III/cirugía , Mandíbula/cirugía , Osteotomía Mandibular/métodos , Maxilar/cirugía , Osteotomía Le Fort/métodosRESUMEN
PURPOSE: We present our experience with transoral segmental mandibulectomy, in conjunction with vascularized osseous mandibular reconstruction, utilizing an intraoral anastomosis and free of extraoral incisions. Virtual surgical planning and intraoperative navigation were used to help achieve this minimally invasive and scar-free approach. METHODS: A retrospective study was performed on 9 patients who underwent transoral segmental mandibulectomy followed by vascularized osseous reconstruction using an intraoral anastomosis between January 2018 and October 2018. The anastomotic recipient vessels were the facial artery and vein. The outcome variable was defined as the flap survival. Postoperative panoramic radiographs and computed tomography images were obtained for assessment of the neo-mandible. In addition, we performed a cadaver dissection to highlight relevant anatomic details of the facial artery and vein. RESULTS: Successful transoral segmental mandibulectomy was achieved in 9 patients, with an intraoral anastomosis successfully achieved in 8 patients. In one patient, an extraoral anastomosis was required because of challenging facial vein anatomy. Both recipient and donor sites healed uneventfully with a 100% successful rate of flap survival. In all cases, a well-positioned neo-mandible with good occlusion was demonstrated on postoperative imaging and examination. A symmetric facial appearance with no restrictions in mouth opening was also achieved in each case. In our cadaver dissection, we describe the anatomical course of the facial artery and vein. An average angle of 30° between these vessels is identified. CONCLUSIONS: Transoral segmental mandibulectomy combined with intraoral microvascular mandibular reconstruction is a surgically achievable technique with the benefit of being scar free.
Asunto(s)
Colgajos Tisulares Libres , Neoplasias Mandibulares , Reconstrucción Mandibular , Procedimientos de Cirugía Plástica , Trasplante Óseo/métodos , Cadáver , Cicatriz , Colgajos Tisulares Libres/cirugía , Humanos , Neoplasias Mandibulares/cirugía , Osteotomía Mandibular/métodos , Reconstrucción Mandibular/métodos , Estudios RetrospectivosRESUMEN
BACKGROUND: The procedure of mandibular angle osteotomy (MAO) via an intraoral approach is challenging and experience-dependent due to the limited field of view and inadequate operational space. Uncertainty about the osteotomy line and plane can lead to severe complications. A three-dimensional printed guidance template based on a computer-assisted preoperative simulation is a potential solution to this problem. The current study aims to retrospectively investigate the feasibility and accuracy of using a custom-made segmented template to guide the osteotomy plane during the procedure. METHODS: Sixty patients who had segmented template-guided MAO were included in the study. Preoperative simulation using the custom-designed template and postoperative computed tomography were collected and parameters, including mandibular angle, gonion distance, and the mandibular plane angle were measured. A paired t tests and intraclass correlation coefficients (ICCs) were used to evaluate the efficacy, accuracy, and symmetry of the results. All complications were reviewed. RESULTS: The patients had a significantly larger mandibular angle and narrower gonion distance postoperatively. Preoperative simulations and postoperative outcomes were compared; ICCs were larger than 95% indicating significant agreement. Bilateral postoperative comparisons of the mandible also demonstrated excellent agreement (ICC > 95%). Numbness in the chin area was the most frequent complication but all recovered by 3 months postoperatively. CONCLUSIONS: The custom-made template can guide the osteotomy plane during the MAO procedure and achieve favorable accuracy and symmetry. Direct contact of the saw with the guidance template not only facilitates control of the osteotomy line but also the oblique angle of the osteotomy plane. This methodology may be a feasible and effective tool for mandibular contouring.
Asunto(s)
Mandíbula , Osteotomía Mandibular , Humanos , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Osteotomía Mandibular/métodos , Monoaminooxidasa , Osteotomía , Estudios RetrospectivosRESUMEN
BACKGROUND: In this study, an AI osteotomy software was developed to design the presurgical plan of mandibular angle osteotomy, which is followed by the comparison between the software-designed presurgical plan and the traditional manual presurgical plan, thus assessing the practicability of applying the AI osteotomy software in clinical practices. METHODS: (1) Develop an AI osteotomy software: design an algorithm based on convolutional neural networks capable of learning feature point and processing clustering segmentation; then, select 2296 cases of successful 3D mandibular angle osteotomy presurgical plans, followed by using those 2296 cases to train the deep learning algorithm; (2) compare the osteotomy presurgical plan of AI osteotomy software and that of manual: first step: randomly selecting 80 cases of typical female head 3D CTs, and designing those 80 cases by means of AI osteotomy software designing (group A) and manually designing (group B), respectively; second step: comparing several indexes of group A and those of group B, including the efficiency index (time from input original CT data to osteotomy presurgical plan output), the safety index (the minimum distance from the osteotomy plane to the mandibular canal), the symmetry indexes (bilateral difference of mandibular angle, mandibular ramus height and mandibular valgus angle) and aesthetic indexes (width ratio between middle and lower faces (M/L), mandibular angle and mandibular valgus angle). RESULTS: The efficiency index: the design time of group A is 1.768 ± 0.768 min and that of group B is 26.108 ± 1.137 min, with P = 0.000; the safety index: The minimum distances from the osteotomy plane to the mandibular canal are 3.908 ± 0.361mm and 3.651 ± 0.437mm, p = 0.117 in groups A and B, respectively; The symmetry indexes: Bilateral differences of mandibular angle are 1.824 ± 1.834° and 1.567 ± 1.059° in groups A and B, respectively, with P = 0.278; bilateral differences of mandibular ramus height are 2.083 ± 1.263 and 2.965 ± 1.433, respectively, with P = 0.119 in groups A and B; Aesthetic indexes: M/L in groups A and B is 1.364 ± 0.074 and 1.371 ± 0.067, respectively, with P = 0.793; mandibular angles in groups A and B are 127.724 ± 5.800° and 127.242 ± 5.545°, respectively, with P = 0.681; Valgus angles in groups A and B are 11.474 ± 5.380 and 9.743 ± 4.620, respectively, with P = 0.273. CONCLUSIONS: With high efficiency, as well as safety, symmetry and aesthetics equivalent to those of a manual design, the AI osteotomy software designing can be used as an alternative method for manual osteotomy designing. 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.
Asunto(s)
Inteligencia Artificial , Osteotomía Mandibular , Femenino , Humanos , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Osteotomía Mandibular/métodos , Osteotomía/métodos , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic tumor. It is characterized by showing, on histopathological examination, clusters of vacuolated and clear tumor cells with epithelial differentiation surrounded by fibrocollagenous stroma and fibroblasts. The present study presents a rare clinical case of mandibular CCOC associated with an impacted tooth in a 26-year-old woman surgically treated with mandibulectomy and reconstruction with iliac crest bone graft. The patient has been followed up for 22 months without signs of recurrence. A search for case report/case series was carried out in the PUBMED database, as well as in the references of relevant previously published literature reviews. Ninety-six publications were identified, totaling 136 distinct cases reported. Female sex was the most affected (63.1%) with 63.3% of cases occurring in patients in the fifth, sixth, or seventh decades of life. The mandible was more affected than the maxilla (74.2%). Association of CCOC with impacted teeth was found in 2.4% of cases, thus rendering it a rare occurrence. The present case report corroborates the results of the survey regarding sex and anatomical location of the tumor; however, it contradicts the findings regarding age predilection. The case described is the fourth known occurrence of tooth impaction associated with the tumor and the first in a female. In conclusion, CCOC should be considered, as well as other malignancies, as a possible diagnosis of maxillary or mandibular intraosseous lesions even in unusual circumstances such as in association with impacted teeth and in young patients.