Article

The Frankfort Plane and Head Positioning in Facial Aesthetic Analysis-The Perpetuation of a Myth

Authors:
To read the full-text of this research, you can request a copy directly from the author.

Abstract

The positioning of a patient’s head prior to clinical evaluation is critical, and incorrect positioning will inevitably lead to errors in diagnosis and treatment planning. Despite its importance, the concept of head positioning in facial aesthetic evaluation is often misunderstood. The reasons for this are partly historical.¹ Anthropologists in the mid to late 19th century in Germany had endeavored for some time to reach a general agreement among themselves as to a method of measuring skulls, obtained from archaeological excavation sites, that could be generally adopted. The purpose was to standardize the techniques used by physical anthropologists, particularly in order to undertake comparative studies of the crania from various ethnic populations. The outcome of deliberations at 2 craniometric conferences, held in Munich in 1877 and subsequently in Berlin in 1880, was drawn up by the anthropologists Julius Kollman, Johannes Ranke, and Rudolf Virchow and submitted for consideration to the 13th General Congress of the German Anthropological Society held in Frankfort (or Frankfurt) in 1882. Their scheme was adopted and designated the Frankfort Agreement (1882) and was published in Germany in 1884.² To compare various crania in a standardized way, it was necessary to place the dry skulls in a defined position. Therefore, the choice of a horizontal reference plane for the orientation of the skulls was agreed on, based on but slightly modified from a plane described by von Ihering in 1872.¹ This so-called German horizontal plane passed through the “lowest point of the under edge of the orbits and the upper edge of the ear-aperture,”² though such a plane is clearly visible on a number of Leonardo da Vinci’s proportional drawings.³ Nevertheless, the Frankfort Agreement of 1882 was the birth of the use of the Frankfort horizontal plane.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the author.

... When a standard symmetric face-bow is used for a patient with an asymmetric external acoustic meatus (EAM), an error may occur in the transferred maxillary position relative to the sagittal axis. This makes the midline non-coincident with the midsagittal plane and raises the dental arch on one side; therefore, the occlusion may not be functional or esthetic (Shah et al., 2016;Wei et al., 2011;Gateno et al., 2003;Kim et al., 2010Kim et al., , 2014Sherry and Jain, 2017;Naini, 2013). ...
... The results of their study were the opposite of the results of our study.Since the occlusal plane is adjusted in the patient's mouth, according to the anatomical and esthetic criteria, when using a standard face-bow for transferring the rims to the articulator on a face with an asymmetric EAM, an error may occur in the transferred maxillary position relative to the sagittal axis. This makes the midline noncoincident with the midsagittal plane, raises the dental arch on one side, and therefore, results in a non-functional or non-esthetic occlusion(Shah et al., 2016;Wei et al., 2011;Gateno et al., 2003;Kim et al., 2010;Sherry and Jain, 2017;Naini, 2013).Moreover, the asymmetry of the external ear holes causes the rims to tilt in the articulator and causes confusion for the technician; also, the present results, there was no significant difference in the mean distance ofthe right and left EAMs from the midsagittal line in different positions of the vertical symmetry of EAMs. In a study by Min-Gun Kim et al. on the 3D symmetry and alignment of skeletal porion and soft tissue, the anterior-posterior angular deviation between these two landmarks was measured. ...
Article
Full-text available
This study aimed to investigate the vertical symmetry of the external acoustic meatus (EAM) and its relationship with the occlusal plane in an Iranian population. The digital facial images of 220 individuals with a face-bow device were acquired. The image size was adjusted to the actual size, using a photo editing software. Also, the desired points and reference lines were measured and recorded by using the software tools. The collected data were analyzed, using Kolmogorov-Smirnov test, independent t-test, one-way ANOVA, and post-hoc test (α=0.05). The higher position of the right ear EAM, the higher position of the left ear EAM, and their vertical symmetry were observed in 51.5%, 44.1%, and 4.5% of the images, respectively. The mean vertical distance between the meeting points of the right and left ear EAMs on the midsagittal plane, as well as the angle between the EAMs and the midsagittal plane, varied among three modes of the vertical symmetry of EAMs. However, no significant difference was found in the mean angle of the line crossing the EAM with the midsagittal line and the occlusal plane for the three modes. The results showed that the vertical symmetry of the EAMs was not correlated with sex or age. The vertical symmetry of the EAM was only observed in 4.5% of the participants.
... Porion (Po) is described as the superior most point on outer surface of the bony external auditory meatus and can be referred to as anatomic Po [3] . It has been used to build the Frankfort horizontal (FH) plane, which has been employed extensively as a horizontal reference plane in anthropometric and cephalometric analysis since its introduction in 1884 [4] "natural head orientation" of the skull direction of the scalp, and behind time utilized by dentists for the orienting the head and film during cephalometry, and for orientation of the cast in articulator [5] 1. EMBRYOLOGY: Pearson's [6] magnificent work has led to the following description about the embryology of External Auditory Canal (EAC). The external auditory canal develops from the first bronchial cleft, which is positioned between the mandibular and hyoid arches which develops from the dorsal portion. ...
Article
Full-text available
In orthodontic cephalometric analysis the two most principal points of interest are the "porion" and the "condylion". Many recent analysis are based on the rigidity of estimates of these factors. A re-examination of their reliability was considered appropriate in light of the renewed interest of these points in cephalometric analysis. Factors influencing variability in the detection of cephalometric landmarks are (1) the roentgenographic process, (2) the anatomic and regional complexity [1] and (3) the location of the historical markers on the cephalogram during the follow-up period [2]. With the emergence of standardisation of the roentgenographic-cephalometric technique the variance has declined equally. But still, the variance occurring due to the manual location of the points subsist. This review was taken up to make porion point reliable and reproducible, and to determine the malocclusion status with the shape of the external auditory meatus.
... En relación con la posición del paciente, uno de los parámetros a considerar a la hora de realizar registros fotográficos es la posición de su cabeza. Una postura incorrecta podría llevar a cometer errores tanto en el diagnóstico como en la planificación del tratamiento (9) , por lo cual se ha propuesto utilizar la Posición Natural de Cabeza (PNC), término que describe a la posición más balanceada, innata, fisiológica y reproducible cuando el paciente se encuentra de pie o sentado, observando un objeto a la altura de los ojos (10,11) . ...
Article
Full-text available
Introducción: La fotogrametría es el proceso por el que se obtienen medidas a partir de una fotografía. Para realizar una correcta toma fotográfica es de suma importancia estandarizar la técnica con el objetivo de obtener registros confiables y reproducibles. Uno de sus requisitos es definir la posición de la cabeza, ya que una postura incorrecta puede conducir a errores en el diagnóstico y planificación del tratamiento. Objetivo: Establecer un protocolo clínico para estandarizar registro fotográfico y posicionamiento del paciente para fotogrametría facial. Materiales y métodos: Se realizaron fotografías faciales estandarizadas a un total de 163 estudiantes. A 76 estudiantes se les realizaron mediciones faciales directas e indirectas. A 87 estudiantes se les comparó su Posición Natural de Cabeza en 3 momentos del día. Se compararon estadísticamente los resultados. Resultados: Al aplicar un protocolo estandarizado, no hubo diferencia estadística entre las medidas directas e indirectas ni al comparar la posición de la cabeza de cada estudiante. Conclusión: La estandarización del set fotográfico expuesto en este trabajo es válida para realizar registros fiables y útiles como examen complementario utilizando la Posición Natural de Cabeza, que permite mantener una posición confiable y estable en el tiempo.
... Kişi uzanarak yattığında, Frankfurt Horizontal Planı vertikal planda olur. Başın tüm antropometrik ölçümlerinde başın standart pozisyonda olması gerekir (Naini 2013, Farkas 1994. ...
Conference Paper
Full-text available
Öz: Diz eklemi; kas, kapsül, menüsküs, sı̇novya, tendon ve lı̇gamanlardan oluşan bir anatomik boşluktur. Tüm bu yapılar dize stabilite yanı sıra hareket özgürlüğü tanır. Nedeni tam bilinmemekle ilerleyen yaşla kıkırdak başlangıçlı eklemi oluşturan yapılardaki histopatolojik bozulmayla osteoartrit olarak tanımlanan dizde ağrı, şişlik, etraf dokulardaki değişimle hareket kısıtlılığı ve atrofi gelişir. Kişinin hareket kabiliyeti ve yaşam kalitesi bozulur. Osteoartrit çoğunluğu farmakolojik yolla tedavi edilse de yine de eklem içi ve etraf dokularda atrofi ve eklem hareket açıklığı kaybı gibi kayıplar gelişebilir. Bu kayıpları önleme veya geri kazanmadaki tedavilerden biri rehabilitasyon programıdır. Gerekli etik onaylar alınarak, SBÜ Gazi Yaşargil Eğitim Araştırma Hastanesi Fiziksel Tıp ve Rehabilitasyon Polikliniğine başvuranlar arasında en az 6 aydır devam eden osteoartrit tanısı konulmuş ve bu amaçla farmakolojik tedavi almış kişiler, belirlenen muayene kriterine göre atrofi ve eklem hareket açıklığı bozulan, ilerlememiş radyolojik değişimli 70 hasta, rastgele seçilerek iki ayrı grupta değerlendirildi. Tekrar ilaç verilmeden, 3 hafta ve günde 2 kez eşit sürede uygulayacağı ev programı/aile eğitimi kapsamında, ağrı sınırında birinci guruba “Eklem Hareket Açıklığı”, ikinci gruba “İzometrı̇k Güçlendirme” egzersizi ayrıca hastanın aktif/pasif katılımı dikkate alınarak refakatçı eşliğinde eğitim verildi. Hastaların çoğunlukla kadınlardan oluştuğu (%83,3, n=57), hastaların yaş ortalaması ve standart sapma 65±9,4 olduğu, orta�lama boy ve standart sapma 163,3cm±7,6cm olduğu ve ortalama kilo ve standart sapmanın 80,4 kg±15,3kg olduğu tespit edilmiştir. Hastaların hesaplanan ortalama Vücut Kitle İndeksleri ve standart sapma 30,3±6,2 olarak tespit edilmiştir. Her iki gruptaki hastalara ilk başvuruda ve 3 haftalık egzersiz sonrası kontrolde, Lequesne Algofonksiyon İndeks Ölçeği uygulanmış ve söz konusu ölçek 0 ile 24 puan arasında skorlanmaktadır. Gruplara ilk ve son skorlar doğrultusunda bağımsız örneklem t-testi uygulanmıştır. Elde edilen sonuçlara göre her iki grup arasında egzersiz etkinliği açısında anlamlı farklılık bulunmuştur (p<0,05). Söz konusu ölçeğin ilk ve son puanları arasındaki fark incelendiğinde, Hareket Açıklığı Egzersizi uygulayan gruptaki ortalama fark ve standart sapması 9±3 iken, İzometrik Egzersiz uygulayan gruptaki ortalama fark ve standart sapması 7±3 olarak tespit edilmiş ve Hareket Açıklığı Egzersizlerinin daha etkin olduğu görülmüştür. Uygulanan programla hastaların geliş şikayetlerinde anlamlı iyileşmelerin olduğu tespit edilmiştir.
... It is seen that views on this confusion have also been indicated previously in the literature. 8 Naini 8 reported that the patients should be examined on the natural head position in order to accurately evaluate the facial proportions and stated that clinicians who advocate the use of the Frankfort horizontal plane should be aware of the shortcomings, especially in patients with severe facial deformities. On the other hand, a few years later, Capon 9 asked to consultants, and clinical photographers which of these 2 methods was more effective, and 77% of the participants stated that they considered the Frankfort horizontal plane to be the most effective alignment method. ...
... 1 Various reference planes have been described for head orientation, both ex-tracranial and intracranial. 2 One of the most commonly used is the Frankfort horizontal (FH) plane, which was first described in the Frankfort Craniometric Agreement (1882), 3 and was defined as a plane that passes through the upper rim of the external acoustic meatus (porion, Po) and the lowest point of the orbital rim (orbitale, Or). 2,3 However, a potential variability has been observed with the FH plane and similar planes that use only intracranial landmarks, because the anatomical landmarks are influenced by individual biological variability. ...
Article
The purpose of this study was to assess the relationship between the Frankfort horizontal (FH) and natural head orientation (NHO), their correlation between patients’ malocclusion, and the impact of counterclockwise rotation (CCW) on the FH-NHO angle variation after orthognathic surgery. An evaluation of 187 consecutive patients was performed at the Maxillofacial Institute (Teknon Medical Center, Barcelona). FH-NHO° was measured pre- and postoperatively at 1 and 12 months, after three-dimensional (3D) superimposition using a software (Dolphin®). Patients were classified as follows: 3.2%, 48.7% and 48.1%, class I, II and III, respectively. Baseline FH-NHO° was significantly positive for patients with dentofacial deformities (2.73° ± 4.19 (2.12–3.33°, P < 0.001). The impact of orthognathic surgery in FH-NHO° was greater in class II when compared with class III patients, with a variation of 2.04° ± 4.79 (P < 0.001) and −1.20° ± 3.03 (P < 0.001), respectively. FH-NHO° increased when CCW rotational movements were performed (P = 0.006). The results of this study suggest that pre- and postoperative NHO differs from FH in orthognathic patients. The angle between FH and NHO is significantly larger in class III than in class II patients at baseline, which converges after orthognathic surgery when CCW rotation is performed. Therefore, NHO should be used as the real horizontal plane when planning for orthognathic surgery.
... Recumbent length was measured to the nearest 0.1 cm using an infantometer (SECA 207, SECA, Hamburg, Germany). With the help of a nurse, the infant was laid down and her/his head was placed in the Frankfort plane (as the best anatomical indicator of a physiological position for a population without facial deformities) [24]. Length was measured from the crown of the head to the foot's heel, while both were appropriately attached to the infantometer. ...
Article
Full-text available
Background Body composition in infancy plays a central role in the programming of metabolic diseases. Fat mass (FM) is determined by personal and environmental factors. Anthropometric measurements allow for estimations of FM in many age groups; however, correlations of these measurements with FM in early stages of life are scarcely reported. The aim of this study was to evaluate anthropometric and clinical correlates of FM in healthy term infants at 6 months of age. Methods Healthy term newborns (n = 102) from a prospective cohort. Weight, length, skinfolds (biceps, triceps, subscapular and the sum -SFS-) and waist circumference (WC) were measured at 6 months. Body mass index (BMI) and WC/length ratio were computed. Type of feeding during the first 6 months of age was recorded. Air displacement plethysmography was used to asses FM (percentage -%-) and FM index (FMI) was calculated. Correlations and general linear models were performed to evaluate associations. Results Significant correlations were observed between all anthropometric measurements and FM (% and index)(p < 0.001). Exclusive/predominant breastfed infants had higher FM and anthropometric measurements at 6 months. Models that showed the strongest associations with FM (% and index) were SFS + WC + sex + type of feeding. Conclusions Anthropometry showed good correlations with FM at 6 months of age. Skinfolds sum and waist circumference were the strongest anthropometric variables associated to FM. Exclusive/predominant breastfeeding was strongly associated with FM.
... The Frankfort Horizontal (FH) was established in 1884 by anthropologists who required a standard method to measure skulls found on archaeological digs (Farhad, 2013). The horizontal reference line supposedly produces maximum differences between racial groups at the same time producethe least amount of variability within each group ( 'that plane which is determined by two straight lines (one on either side of the skull), connecting the lowest points on the inferior margins of the orbits with the points of the upper margins of the bony auditory meatus situated vertically above their centres' (Gaeson, 1884). ...
Article
Full-text available
The Frankfort Horizontal (FH) is used by clinical photographers as a reference plane to help maintain Standardised Representational Photography (SRP) when photographing a patients head. A comparative method of alignment is the Natural Head Position (NHP). For this study a survey was created that asked consultants and clinical photographers which method of alignment they considered to be the most effective. The survey found that 77% of respondents thought the FH was the most effective method of alignment. This high figure is due to some confirmation bias as the FH is the industry standard.
... It is defined as the most superior and outer bony surface point of the external auditory meatus and can be called as the anatomical Po [1]. It has been employed to construct the Frankfort horizontal (FH) plane, which has been frequently used as a horizontal reference plane for the anthropometric and the cephalometric analysis since its introduction in 1884 [2]. ...
Article
Full-text available
Background: The porion (Po) is used to construct the Frankfort horizontal (FH) plane for cephalometrics, and the external auditory meatus (EAM) is to transfer and mount the dental model with facebow. The classical assumption is that EAM represents Po by the parallel positioning. However, we are sometimes questioning about the possible positional disparity between Po and EAM, when the occlusal cant or facial midline is different from our clinical understandings. The purpose of this study was to evaluate the positional parallelism of Po and EAM in facial asymmetries, and also to investigate their relationship with the maxillary occlusal cant. Methods: The 67 subjects were classified into three groups. Group I had normal subjects with facial symmetry (1.05 ± 0.52 mm of average chin deviation) with minimal occlusal cant (<1.5 mm). Asymmetry group II-A had no maxillary occlusal cant (average 0.60 ± 0.36), while asymmetry group II-B had occlusal cant (average 3.72 ± 1.47). The distances of bilateral Po, EAM, and mesiobuccal cusp tips of the maxillary first molars (Mx) from the horizontal orbital plane (Orb) and the coronal plane were measured on the three-dimensional computed tomographic images. Their right and left side distance discrepancies were calculated and statistically compared. Results: EAM was located 10.3 mm below and 2.3 mm anterior to Po in group I. The vertical distances from Po to EAM of both sides were significantly different in group II-B (p = 0.001), while other groups were not. Interside discrepancy of the vertical distances from EAM to Mx in group II-B also showed the significant differences, as compared with those from Po to Mx and from Orb to Mx. Conclusions: The subjects with facial asymmetry and prominent maxillary occlusal cant tend to have the symmetric position of Po but asymmetric EAM. Some caution or other measures will be helpful for them to be used during the clinical procedures.
... On a lateral cephalometric radiograph, the Frankfort horizontal plane is represented by a line connecting the skeletal cephalometric landmarks of the porion (the superior border of the external acoustic meatus) and orbitale (the superior border of the inferior orbital rim) ( Figure 1). 3 The advantages of the zero-degree meridian are its ease of use and that it has been demonstrated to be in accordance with the idealized profiles of classical, Renaissance, and neoclassical artistic canons. 4 However, in using this analysis, it should be kept in mind that the inclination of the Frankfort horizontal plane, as with all anatomical reference planes, is unlikely to be coincident with the true horizontal, particularly in a patient with a dentofacial or position, in relation to a hanging "true vertical" plumb line, parallel to which may be drawn the zero-degree meridian and perpendicular to which is drawn a true horizontal line, to act as the Frankfort plane. ...
Article
The roots of clinical facial aesthetic analysis stem from the theoretical musings of pioneering artists and sculptors, stretching back to antiquity. The use of such analyses in clinical practice has been modified in accordance with changing cultural perceptions and better understanding of age-, sex-, and ethnicity-specific anthropometric and cephalometric normative data for various craniofacial parameters. Nevertheless, the work of the great artists and sculptors of past ages remains inherent in our ability to accurately diagnose variations in facial appearance. The objective of this letter is to delve into the origin of one of the most widely used facial aesthetic analyses, the zero-degree meridian of the facial profile, based on 2 images recently detected within the Leonardo da Vinci archives of the Royal Collection (Windsor Castle, England), which is the largest Leonardo da Vinci collection in the world. The zero-degree meridian was described and named by the Mexican plastic surgeon Mario Gonzalez-Ulloa as a …
Article
It is a pleasure to provide a commentary on this interesting and timely article by Lobato et al from the University of São Paolo, Brazil.¹ The authors have described a relatively simple technique using the modern smartphone and an easily implemented application with the available Blender software, previously described by Moraes, to evaluate chin volume before and after augmentation with autologous fat transfer.² They have also compared their results with traditional computed tomography (CT) scans. The authors begin by explaining the importance of 3-dimensional (3D) assessment when considering facial volume changes. They go on to describe the use of CT and MRI as the modern basis for obtaining such data. Despite the improvements in CT technology, including cone beam CT and overall reductions in radiation dosage, CT is not risk-free, and MRI has its own problems, including the claustrophobic nature of the scans, the inherent noise, and the time needed to scan. There is also the cost and running of the machines. The authors go on to briefly describe the technique of photogrammetry, utilizing structured light to obtain 3D images, and subsequently undertaking quantitative measurements for comparative purposes. The authors state that, “There is abundant evidence regarding accuracy of facial scanning by photogrammetry, but no reports on the accuracy of facial scanning with smartphone applications.”¹ The first part of this statement is not referenced and requires further evaluation. Although there are certainly abundant publications on different types of photogrammetry, the accuracy of each technique has not been found to be ideal, and validation of each technique and its clinical application is essential.
Chapter
Problems in the vertical dimension are some of the most challenging problems that an orthodontist must deal with. This chapter provides a review of the etiology, diagnosis, and early treatment of vertical problems: dental deep bites, skeletal deep bites, dental open bites, skeletal open bites, and posterior open bites. It uses a question‐and‐answer format to encourage the reader to think critically and gage the progress of his/her understanding. The chapter presents a vast collection of high‐quality images illustrating the conditions and appropriate therapies. Perfect for orthodontists, pediatric dentists, and dentists in general practice, it is also useful to residents and dental students with an interest in orthodontic care.
Chapter
It is important to know what to look for! It is a combination of science, art, and skill to be able to imagine the multilayer nature of the face, the relationship of various structures with each other, their impact on one another, and how different treatments can impact them. The understading of non-surgical facial aesthetics cannot be reduced to a small number of simple injections to erase frown lines or fill the nasolabial folds. The mystery and artistry of this field lie within understanding anatomy, facial morphology (general and ethnic for both genders), facial expressions and psychology related factors, facial ageing, and morphological changes that occur during the different stages of ageing. Furthermore, understanding of the domino effect of changes in a negative or positive manner in one part of the face, the effect of the foundation of the face (dentoskeletal structure) on soft tissue morphology, age and disease related changes and the effect of lighting, head position and assessment aids used. A skillful assessment of the face and successful treatment planning requires knowledge and training, practice, repetition, and the development of an aesthetic eye.
Article
Objetivo: el objetivo de este estudio fue determinar la discrepancia del Plano de Frankfurt evaluado en fotogrametría y en cefalometría de radiografías laterales de cráneo respecto a la horizontal verdadera. Materiales y métodos: el estudio consideró a 34 voluntarios de la clínica del Postítulo de Ortodoncia y Ortopedia Dento Máxilo Facial de la Facultad de Odontología de la Universidad de Chile. Se utilizaron sus radiografías laterales de cráneo orientadas según el Plano de Frankfurt paralelo al piso y se les tomó una fotografía facial de perfil estandarizada en Posición Natural de Cabeza. Se trazó el Plano de Frankfurt y la Horizontal Verdadera en ambos exámenes y se midió el ángulo formado entre estos planos. Resultados: al comparar los ángulos mediante T-test, no hubo diferencia estadística. Conclusiones: mediante la aplicación de un protocolo sistematizado tanto para el registro fotográfico como para la obtención de la Posición Natural de Cabeza, se puede lograr que el Plano de Frankfurt sea prácticamente coincidente en radiografías laterales de cráneo y en fotografías clínicas, demostrando su uso hasta el día de hoy en la ortodoncia moderna.
Chapter
Current alternatives for xenograft use in correction of lower eyelid retraction are reviewed, together with strategies for patient evaluation, typical surgical techniques, and postoperative management.
An understanding of fundamental orthodontic principles involving diagnosis, treatment planning, and clinical strategies is essential for achieving successful outcomes in the treatment of craniofacial patients, particularly cleft lip/palate. This article focuses on: customizing a mandibular dental arch form using the WALA ridge; accurately diagnosing the maxillary skeletal transverse dimension (cusp to cusp/fossa to fossa); coordinating the upper dental arch with the lower; using a smiling profile and glabella vertical to assess anteroposterior jaw position; and leveling the mandibular curve of Spee while considering the lower one-third of the face. These concepts influence treatment outcomes to the extent they are used.
Article
Whereas 3-dimensional surface imaging and stereophotogrammetry allow plastic surgeons the unparalleled ability to perform quantitative and morphometric analysis, digital still photography remains the mainstay in aesthetic photodocumentation as a result of lower cost and wider adoption.
Chapter
The term 'low angle' refers to patients with a reduced mandibular plane angle (MPA), associated usually with a reduced lower facial height (LFH) and a deep overbite. The direction and amount of condylar growth, temporal fossa growth, vertical growth of the maxilla and tooth eruption determine vertical facial growth. A number of clinical and cephalometric parameters may be evaluated in order to analyse vertical facial form. Both clinical and cephalometric assessments must be undertaken with the patient in natural head position (NHP), which is adopted when relaxed and looking straight ahead at a distant object. Treatment planning is a team inter-disciplinary activity to ensure the best possible outcome to deal with the patient's concerns. A digital profile photograph ideally taken simultaneously or immediately after the radiograph with the soft tissues in the same position aided by the wax wafer, as required, can then be superimposed using proprietary software for planning purposes.
Chapter
This chapter provides a step-by-step guide to clinical diagnosis specifically for the orthognathic surgical patient. Diagnosis remains the single most important step in the clinical management of any patient. It is often said that 'a journey of a thousand miles begins with a single step'. In terms of clinical treatment, it thereby follows that if this step is in the wrong direction, then no matter the speed of treatment or expertise in technique, one is nevertheless travelling in the wrong direction. Comprehensive clinical diagnosis of the craniofacial complex and the analysis of diagnostic records have been described elsewhere. The clinician should look for any signs of physical illness or potential psychosocial disturbances, which may be evident in the patient's posture, demeanour or their general manner, and particularly in the relationship between younger patients and their parents. The importance of a patient's social support network, particularly family support, should never be underestimated.
Article
BACKGROUND: The maintenance of horizontal gaze is an essential function of upright posture and global sagittal spinal alignment. Horizontal gaze is classically measured by the chin-brow vertical angle (CBVA), which is not readily measured on most lateral spine radiographs. OBJECTIVE: To evaluate relations between CBVA and the slope of the line of sight, the slope of McGregor's line (McGS), and Oswestry Disability Index. METHODS: Patients were identified from a single center database of 531 spine patients who underwent full-body EOS x-rays. Correlations between CBVA, the slope of the line of sight, and McGS were assessed. Using a quadratic regression with Oswestry Disability Index and CBVA, windows of low disability were identified. Comparison of sagittal spinopelvic parameters was carried out between patients with "ascending gaze" and "neutral position." RESULTS: Three hundred three patients were included (74% female, mean age 54.8 years, body mass index 26.6 +/- 6.0 kg/m2). CBVA strongly correlated with the slope of the line of sight (r = 0.996) and McGS (r = 0.862). Regression studies between Oswestry Disability Index and CBVA yielded a range of values corresponding to low disability (-4.7 degrees to 17.7 degrees). Similarly, a low disability range for the slope of the line of sight (-5.1 degrees to 18.5 degrees) and McGS (-5.7 degrees to 14.3 degrees) was computed. Patients with "ascending gaze" had a worse spinopelvic alignment than "neutral position" patients. CONCLUSION: The slope of the line of sight and McGS correlated strongly with CBVA and can be used as surrogate measures. The range of values for these measures corresponding to low disability was identified. These values can be used as a general guideline to assess alignment for diagnostic purposes. Cervical compensatory mechanism may modify the natural head position in sagittally misaligned patients. ABBREVIATIONS: CBVA, chin-brow vertical angle HRQoL, health-related quality of life McGS, slope of McGregor's line ODI, Oswestry Disability Index SLs, slope of the line of sight Copyright (C) by the Congress of Neurological Surgeons
Article
The purpose of this study was to assess the reliability of the Frankfort horizontal (FH), sella-nasion horizontal, and optic planes in terms of their variabilities in relation to a true horizontal line in orthognathic surgery patients. Thirty-six consecutive presurgical orthognathic patients (13 male, 23 female; age range, 16-35 years; 30 white, 6 African Caribbean) had lateral cephalometric radiographs taken in natural head position, with a plumb line orientating the true vertical line, and the true horizontal line perpendicular to the true vertical. The inclinations of the anatomic reference planes were compared with the true horizontal. The FH plane was found to be on average closest to the true horizontal, with a mean of -1.6° (SD, 3.4°), whereas the sella-nasion horizontal and the optic plane had means of 2.1° (SD, 5.1°) and 3.2° (SD, 4.7°), respectively. The FH showed the least variability of the 3 anatomic planes. The ranges of variability were high for all anatomic planes: -8° to 8° for the FH, -8° to 15° for the sella-nasion horizontal, and -6° to 13° for the optic plane. No significant differences were found in relation to patients' sex, skeletal patterns, or ethnic backgrounds. The clinically significant variability in the inclinations of anatomic reference planes in relation to the true horizontal plane makes their use unreliable in orthognathic patients. Copyright © 2014 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.