Stability of Le Fort I maxillary inferior repositioning surgery with rigid internal fixation: a systematic review

The aim of this study was to evaluate the stability of Le Fort I maxillary inferior repositioning surgery in patients with a vertical maxillary deficiency at least 6 months after surgery. The electronic databases were searched to identify all articles reporting the long-term effects of one-piece maxillary inferior repositioning with rigid fixation. Methodological quality was evaluated according to 15 criteria related to study design, measurements, and statistical analysis. Two articles were identified, with a total of 22 patients. The maxilla was repositioned inferiorly from a mean 3.2 to 4.5mm in the anterior part and from a mean 0.1 to 1.8mm in the posterior part. At 6 months post-treatment, absolute relapse of a mean 1.6mm was measured for the anterior part of the maxilla and 0.3mm for the posterior part of the maxilla. The stability of maxillary inferior repositioning surgery could not be confirmed due to the small sample size, unclear diagnosis, and potential confounding factors.

Inicial nasal mucosa detachment using piezoelectric device in the Le Fort I osteotomy: A technical note

In maxillary Le Fort I type osteotomy the detachment of the nasal mucosa should be done carefully. Piezoelectric surgery contributed much to increase the safety of osteotomies, despite the initial advantage of minimizing the risk of injury in nervous tissue, mainly in bilateral sagittal split osteotomy; we use the piezoelectric device for the initial detachment of the nasal mucosa in the maxillary osteotomy.

Incidence of Maxillary Sinusitis Following Le Fort I Osteotomy: Clinical, Radiographic, and Endoscopic Study

Purpose: The correction of maxillomandibular deformities may require maxillary osteotomy procedures that usually present low rates of postoperative complications, such as maxillary sinusitis. The present study evaluated the incidence of maxillary sinusitis after Le Fort I osteotomy in 21 adult patients who underwent maxillary surgery (Le Fort I osteotomy) or bimaxillary surgery (Le Fort I osteotomy plus sagittal mandibular osteotomies) for correction of dentofacial deformities.Patients and Methods: Verification of the presence of maxillary sinusitis was assessed through a brief questionnaire, x-rays (Waters views), and nasal endoscopy before surgery and 6 to 8 months after surgery.Results: Analysis of results showed an incidence of 4.76% of maxillary sinusitis as a postoperative complication in the studied population.Conclusion: Symptomatic patients with a positive radiographic finding or an increased risk for postoperative sinusitis will benefit from endoscopic evaluation to aid in treatment planning and follow-up. 0 2011 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 69:346351, 2011

The use of a bite fork to help mobilize the maxilla after downfracture during the Le Fort I osteotomy: a technical note

Introduction The Le Fort I osteotomy is indicated to reposition the maxilla in the surgical correction of dentofacial deformities. Although it is a known surgical step, like any surgical procedure, it can have complications and difficulties; among these, the initial mobility of the jaw is very common after completing all corticotomies. Methods The authors present a technique in which the bite fork is used as an auxiliary tool in maxilla downfracture, especially in cases of maxillary impaction where vertical space is created on the walls of the corticotomy. Findings As the bite fork acts as a scraper with a long leverage arm, an advantage would be the better distribution of forces along the corticotomy, minimizing the risk of bad fracture and facilitating maxillary downfracture movement.

Alterações no perfil dos lábios de pacientes submetidos a avanços maxilares em cirurgia ortognática do tipo Le Fort I

A literatura que descreve os resultados das correções cirúrgicas nos tecidos moles é limitada, pois apresenta significativa variação e não oferece conclusões definitivas. O propósito desse artigo é estudar retrospectivamente os efeitos das cirurgias ortognáticas maxilares tipo Le Fort I nos lábios superiores e inferiores de pacientes adultos e discutir os potenciais problemas envolvidos com a metodologia aplicada. Foram estudados 19 pacientes brancos de 19 a 42 anos de idade, sendo 10 homens e 9 mulheres, submetidos a cirurgias maxilares no Centro de Pesquisa e Tratamento das Deformidades Buco-Faciais - CEDEFACE (Araraquara, SP). A grande maioria dos casos apresentou, no mínimo, uma discrepância significativa, seja ântero-posterior ou vertical, reforçando a sua indicação cirúrgica. As alterações nos tecidos moles foram significativas quando as movimentações horizontais ou verticais da base óssea maxilar foram significativas, com uma relação de aproximadamente 0,6:1 entre as alterações ântero-posteriores do lábio superior e a movimentação da base óssea. Alterações verticais na maxila, sem significativas alterações horizontais, não foram suficientes para aumentar verticalmente o lábio superior. Ocorreram alterações ântero-posteriores do lábio inferior em conseqüência do deslocamento anterior e inferior da maxila, o que permitiu um melhor selamento labial. Alterações verticais não foram quantificadas no lábio inferior.

Estudo clínico randomizado duplo cego comparando duas técnicas de plicatura nasal após osteotomias tipo Le Fort I

A correção de deformidades esqueléticas da face por meio de um tratamento ortodôntico-cirúrgico tornou-se uma opção segura e previsível. Os movimentos ósseos são milimetricamente calculados e executados cirurgicamente, assim como a oclusão é meticulosamente engrenada através dos movimentos ortodônticos. Os efeitos que os tecidos moles sofrem com as cirurgias ortognáticas são, no entanto, menos previsíveis, e apesar do principal objetivo da cirurgia ortognática ser uma melhora funcional, o componente estético é sem dúvida de extrema importância. Em especial, a região de base alar apresenta resultados muito variáveis, a despeito dos bons resultados esqueléticos atingidos. O objetivo deste estudo foi comparar 2 diferentes tipos de sutura utilizados na região de base do nariz, e observar qual tipo apresenta um resultado que melhor acompanhe os movimentos realizados pelo tecido esquelético. Trinta e cinco pacientes foram aleatoriamente distribuídos em 2 grupos. O grupo 1 funcionou como controle e os pacientes receberam a plicatura nasal intra-oral, que é o tipo de plicatura nasal mais descrito na literatura. Já os pacientes do grupo 2 receberam plicatura nasal extra-oral. Para análise estatística foram calculadas as médias e desvios padrões dos grupos, e a hipótese nula de que não havia diferença entre os 2 grupos foi testata com o teste T de Student. Em ambos os grupos ocorreu um alargamento da base do nariz, porém a média de alargamento do grupo 1 foi de 2,50 milímetros (mm), enquanto que a média de alargamento do grupo 2 foi de 1,26 mm. Além disso, o desvio padrão foi menor para o grupo 2, e a hipótese nula foi rejeitada (p<0,05), demonstrando que a diferença entre os grupos foi estatisticamente significativa. Pôde-se concluir que quando objetiva-se um controle mais previsível e rigoroso da base do nariz, a plicatura nasal extra-oral cumprirá melhor esta função.

Avaliação da fidelidade da referência externa em tecidos moles na cirurgia ortognática da maxila

Esse trabalho teve o objetivo de analisar a fidelidade da referência externa em tecidos moles no auxílio do posicionamento vertical da maxila. Foram selecionados 40 pacientes portadores de deformidade dentofacial e submetidos à osteotomia total da maxila. Os indivíduos foram divididos em 2 grupos no intuíto de avaliar duas técnicas de referência externa: a utilização da sutura em tecidos moles e o uso do fio de Kirschner. Esta última foi utilizada como a técnica do grupo-controle. Os dados foram colhidos em duas fases. Na primeira delas, foi realizada a mensuração da posição vertical da maxila antes da osteotomia Le Fort I e após a fixação da maxila, utilizando a referência externa. A partir desses números, foi obtida a alteração vertical de cada caso, colhida durante a cirurgia. Na segunda fase da coleta de dados, foram realizadas mensurações verticais da maxila baseadas nas radiografias cefalométricas pré e pós-operatórias. Assim, foi obtido o valor da alteração vertical de cada caso, baseado na documentação radiográfica. Após esta etapa, foi calculada a diferença entre a alteração vertical obtida durante a cirurgia e a alteração vertical colhida a partir das radiografias. Dessa forma, foram obtidos valores que correspondem às imperfeições no posicionamento vertical da maxila de cada paciente, tendo como base a posição do incisivo central superior. Os resultados foram comparados e analisados estatisticamente. A média aritmética da precisão no posicionamento vertical da maxila no grupo-controle foi de 0,52mm e do grupo da referência em tecidos moles foi de 0,65mm. A aplicação do teste t de Student a 5% revelou que não houve diferença estatística significativa entre o grau de precisão das duas técnicas de referência externa (P=0,429). Como conclusão, observou-se que as duas técnicas foram eficazes no auxílio ao posicionamento vertical da maxila e que a referência externa em tecidos moles apresentou um grau de precisão semelhante ao valor obtido com a técnica do fio de Kirschner.

Horizontal Maxillary Osteotomy Approach for Resection of Juvenile Nasopharyngeal Angiofibroma

Juvenile angiofibroma is a benign fibroangiomatous tumor of relatively rare occurrence, developing most frequently in male adolescents. It has local characteristics of aggressiveness and expansion. The treatment of choice is surgical excision. In this article, the advantages and disadvantages of the surgical technique using the Le Fort I osteotomy are described, and the literature correlated with 2 case reports.

Three dimensional study to quantify the relationship between facial hard and soft tissue movement as a result of orthognathic surgery

Introduction Prediction of soft tissue changes following orthognathic surgery has been frequently attempted in the past decades. It has gradually progressed from the classic “cut and paste” of photographs to the computer assisted 2D surgical prediction planning; and finally, comprehensive 3D surgical planning was introduced to help surgeons and patients to decide on the magnitude and direction of surgical movements as well as the type of surgery to be considered for the correction of facial dysmorphology. A wealth of experience was gained and numerous published literature is available which has augmented the knowledge of facial soft tissue behaviour and helped to improve the ability to closely simulate facial changes following orthognathic surgery. This was particularly noticed following the introduction of the three dimensional imaging into the medical research and clinical applications. Several approaches have been considered to mathematically predict soft tissue changes in three dimensions, following orthognathic surgery. The most common are the Finite element model and Mass tensor Model. These were developed into software packages which are currently used in clinical practice. In general, these methods produce an acceptable level of prediction accuracy of soft tissue changes following orthognathic surgery. Studies, however, have shown a limited prediction accuracy at specific regions of the face, in particular the areas around the lips. Aims The aim of this project is to conduct a comprehensive assessment of hard and soft tissue changes following orthognathic surgery and introduce a new method for prediction of facial soft tissue changes.   Methodology The study was carried out on the pre- and post-operative CBCT images of 100 patients who received their orthognathic surgery treatment at Glasgow dental hospital and school, Glasgow, UK. Three groups of patients were included in the analysis; patients who underwent Le Fort I maxillary advancement surgery; bilateral sagittal split mandibular advancement surgery or bimaxillary advancement surgery. A generic facial mesh was used to standardise the information obtained from individual patient’s facial image and Principal component analysis (PCA) was applied to interpolate the correlations between the skeletal surgical displacement and the resultant soft tissue changes. The identified relationship between hard tissue and soft tissue was then applied on a new set of preoperative 3D facial images and the predicted results were compared to the actual surgical changes measured from their post-operative 3D facial images. A set of validation studies was conducted. To include: • Comparison between voxel based registration and surface registration to analyse changes following orthognathic surgery. The results showed there was no statistically significant difference between the two methods. Voxel based registration, however, showed more reliability as it preserved the link between the soft tissue and skeletal structures of the face during the image registration process. Accordingly, voxel based registration was the method of choice for superimposition of the pre- and post-operative images. The result of this study was published in a refereed journal. • Direct DICOM slice landmarking; a novel technique to quantify the direction and magnitude of skeletal surgical movements. This method represents a new approach to quantify maxillary and mandibular surgical displacement in three dimensions. The technique includes measuring the distance of corresponding landmarks digitized directly on DICOM image slices in relation to three dimensional reference planes. The accuracy of the measurements was assessed against a set of “gold standard” measurements extracted from simulated model surgery. The results confirmed the accuracy of the method within 0.34mm. Therefore, the method was applied in this study. The results of this validation were published in a peer refereed journal. • The use of a generic mesh to assess soft tissue changes using stereophotogrammetry. The generic facial mesh played a major role in the soft tissue dense correspondence analysis. The conformed generic mesh represented the geometrical information of the individual’s facial mesh on which it was conformed (elastically deformed). Therefore, the accuracy of generic mesh conformation is essential to guarantee an accurate replica of the individual facial characteristics. The results showed an acceptable overall mean error of the conformation of generic mesh 1 mm. The results of this study were accepted for publication in peer refereed scientific journal. Skeletal tissue analysis was performed using the validated “Direct DICOM slices landmarking method” while soft tissue analysis was performed using Dense correspondence analysis. The analysis of soft tissue was novel and produced a comprehensive description of facial changes in response to orthognathic surgery. The results were accepted for publication in a refereed scientific Journal. The main soft tissue changes associated with Le Fort I were advancement at the midface region combined with widening of the paranasal, upper lip and nostrils. Minor changes were noticed at the tip of the nose and oral commissures. The main soft tissue changes associated with mandibular advancement surgery were advancement and downward displacement of the chin and lower lip regions, limited widening of the lower lip and slight reversion of the lower lip vermilion combined with minimal backward displacement of the upper lip were recorded. Minimal changes were observed on the oral commissures. The main soft tissue changes associated with bimaxillary advancement surgery were generalized advancement of the middle and lower thirds of the face combined with widening of the paranasal, upper lip and nostrils regions. In Le Fort I cases, the correlation between the changes of the facial soft tissue and the skeletal surgical movements was assessed using PCA. A statistical method known as ’Leave one out cross validation’ was applied on the 30 cases which had Le Fort I osteotomy surgical procedure to effectively utilize the data for the prediction algorithm. The prediction accuracy of soft tissue changes showed a mean error ranging between (0.0006mm±0.582) at the nose region to (-0.0316mm±2.1996) at the various facial regions.

Strategies for surgically assisted rapid maxillary expansion according to the region of transverse maxillary deficiency

This study evaluated different techniques for surgically assisted rapid maxillary expansion (SARME) according to the type of transverse maxillary deficiency using computed tomography (CT). Six adult patients with bilateral transverse maxillary deficiencies underwent SARME. the patients were equally divided into three groups: Group I, maxillary atresia in both the anterior and posterior regions; Group II, greater maxillary atresia in the anterior region; and Group ill, increased maxillary atresia in the posterior region. in Group I, a subtotal Le Fort I osteotomy was used. in Group II, a subtotal Le Fort I osteotomy was used without pterygomaxillary suture disjunction. in Group III, a subtotal Le Fort I osteotomy was used with pterygomaxillary suture disjunction and fixation of the anterior nasal spine with steel wire. the midpalatal suture opening was evaluated preoperatively and immediately after the activation period using CT. for Group I, the opening occurred parallel to midpalatal suture; for Group II, the opening comprised a V-shape with a vertex on the posterior nasal spine; and for Group III, the opening comprised a V-shape with a vertex at the anterior nasal spine. the conclusion was that the SARME technique should be individualized according to the type of transverse maxillary deficiency.

A new history of the life and reign of the Czar Peter the Great, Emperor of all Russia, and father of his country : Giving an exact relation of I. His travels, studies, and personal fatigues, for the attaining of knowledge in civil and military affairs, and the improvement of his subjects. II. His introduction of arts and sciences, a naval force, and commerce with foreign nations; also his many reformations in church and state, the army, and the customs and manners of his people. III. His wars with the Swedes, Turks, Tartars and Persians; victories by sea and land; acquisitions of territory, and increase of power. IV. His regard to genius and merit, particularly in the instances of General Le Fort, Prince Menzikoff, and the Empress Catharine: and his severe justice on offenders, exemplified in the proceedings against the czarewitz, and others. /

By John Bancks.

Tooth Viability Following Distraction Osteogenesis in Patients with Maxillary Hypoplasia

Thesis (Master's)--University of Washington, 2016-06

Orthognathic Surgery in the Young Cleft Patient: Preliminary Study on Subsequent Facial Growth

Purpose: This study evaluated the long-term effects of orthognathic surgery on subsequent growth of the maxillomandibular complex in the young cleft patient. Patients and Methods: We evaluated 12 young cleft patients (9 male and 3 female patients), with a mean age of 12 years 6 months (range, 9 years 8 months to 15 years 4 months), who underwent Le Fort I osteotomies, with maxillary advancement, expansion, and/or downgrafting, by use of autogenous bone or hydroxyapatite grafts, when indicated, for maxillary stabilization. Five patients had concomitant osteotomies of the mandibular ramus. All patients had presurgical and postsurgical orthodontic treatment to control the occlusion. Radiographs taken at initial evaluation (T1) and presurgery (T2) were compared to establish the facial growth vector before surgery, whereas radiographs taken immediately postsurgery (T3) and at longest follow-up (T4) were used to determine postsurgical growth. Each patient's lateral cephalograms were traced, and 16 landmarks were identified and used to compute 11 measurements describing presurgical and postsurgical growth. Results: Before surgery, all patients had relatively normal growth. After surgery, cephalograms showed statistically significant growth changes from T3 to T4, with the maxillary depth decreasing by -3.3° ± 1.8°, Sella-nasion-point A by -3.3° ± 1.8°, and point A-nasion-point B by -3.6° ± 2.8°. The angulation of the maxillary incisors increased by 9.2° ± 11.7°. Of 12 patients, 11 showed disproportionate postsurgical jaw growth. Maxillary growth occurred predominantly in a vertical vector with no anteroposterior growth, even though most patients had shown anteroposterior growth before surgery. The distance increased in the linear measurement from nasion to gnathion by 10.3 ± 7.9 mm. Four of 5 patients operated on during the mixed dentition phase had teeth that erupted through the cleft area. A variable impairment of postoperative growth was seen with the 2 types of grafting material used. No significant difference was noted in the effect on growth in patients with unilateral clefts versus those with bilateral clefts. The presence of a pharyngeal flap was noted to adversely affect growth, whereas simultaneous mandibular surgery did not. After surgery, 11 of 12 patients tended toward a Class III end-on occlusal relation. Conclusions: Orthognathic surgery may be performed on growing cleft patients when mandated by psychological and/or functional concerns. The surgeon must be cognizant of the adverse postsurgical growth outcomes when performing orthognathic surgery on growing cleft patients with the possibility for further surgery requirements. Performing maxillary osteotomies on cleft patients would be more predictable after completion of facial growth. © 2008 American Association of Oral and Maxillofacial Surgeons.

Complicações após expansão de maxila cirurgicamente assistida

Introduction: The treatment of adult transverse maxillary deficiency is the surgically assisted maxillary expansion. Several surgical techniques have been described for this and complications have been related to these procedures. Objective: the aim of this study was evaluate the incidence of complications associated with surgically assisted maxillary expansion. Material and method: 33 individuals undergone surgically assisted maxillary expansion by subtotal Le Fort I osteotomy with a step in the zygomatic-maxillary buttress and associated to pterigomaxillary disjunction and osteotomy of intermaxillary suture. Operative complications, post-operative complications and the distance between the upper teeth were recorded. Result: 12 men and 21 women with an average age of 24.64 years undergone the procedure. The interdental distances increased from preoperative to 2 months post?operative time. The prevalent complications were sinusitis (6%) and teeth displacement and inclination (6%). Conclusion: Surgically assisted maxillary expansion is an effective and low morbidity procedure to treat transverse maxillary deficiency in adults.