Unit 5 - Facial Normal Features PDF

Unit 5 FACIAL NORMAL FEATURES. FACIAL AESTHETICAL EVALUATION. THE GOLDEN PROPORTION. VISUAL FACE ANALYSIS. FACIAL PATTERNS. FRONTAL AND PROFILE ANALYSIS. LINEAL AND ANGULAR FACIAL PROFILE MEASURES. LIP ANALYSIS. LIP DINAMIC ANALYSIS AND DENTAL EXPOSURE. Orthodon...

Unit 5 FACIAL NORMAL FEATURES. FACIAL AESTHETICAL EVALUATION. THE GOLDEN PROPORTION. VISUAL FACE ANALYSIS. FACIAL PATTERNS. FRONTAL AND PROFILE ANALYSIS. LINEAL AND ANGULAR FACIAL PROFILE MEASURES. LIP ANALYSIS. LIP DINAMIC ANALYSIS AND DENTAL EXPOSURE. Orthodontics I Dra. Elena Muñoz García Bachelor of Dentistry INDEX 1. INTRODUCTION. FACIAL NORMAL FEATURES 2. FACIAL AESTHETICAL EVALUATION. HISTORICAL FACTORS. THE GOLDEN PROPORTION 3. CLINICAL FACIAL ANALYSIS 4. FACIAL PATTERNS. FRONTAL AND PROFILE ANALYSIS. FACIAL PROFILE LINE AND ANGLE MEASURES. LIP ANALYSIS. 5. DENTAL EXPOSURE. DENTOLABIAL ANALYSIS.  1. INTRODUCTION. FACIAL NORMAL FEATURES The facial analysis is essential for the orthodontic diagnostic and treatment planification. At daily routine, there will be two situations: - Patients with a malocclusion which alters the facial harmony, where the objective is to correct both. - Patients with a malocclusion without an alteration of the facial harmony, where the objective is to correct the malocclusion without altering the aesthetic. There are some universal aesthetical features to be considered depending on the era, the culture or even the race, but we don’t have to forget the subjective perception of the patient and its environment, just as the objective professional perception. 2. FACIAL AESTHETICAL EVALUATION. HISTORICAL FACTORS. THE GOLDEN PROPORTION. Beauty is the addition of aesthetic plus harmony. Aesthetic comes from ‘AISTHESIS’, which means having a sense or love of that which is beautiful, in other words, a group of perceptions generated by the observation of an object and the satisfying reaction that it provokes on the observer. Harmony comes from ‘HARMONIA’, which is the convenient proportion and link between things. Worship of beauty explain the high demand of treatment, for that reason, nowadays more patients demand aesthetical harmony too. To achieve that objective, knowledge, experience and artistic skills are needed. Throughout history, the beauty concept has been developed by many cultures. Egyptians symbolized proportionated faces, well-defined, with thick lips and a wide forehead, inclined and prominent. Nowadays this is known as a convex profile. In Mesopotamia, faces were less expressive, with prominent mandibles and wide and expressive eyes. Meanwhile, in Ancient Greece, mathematical equations and geometric formulas were studied in order to design perfect faces to their sculptures. They looked for proportion and harmony. The faces were oval, with a straight forehead, a low hair line, straight nasal dorsum, retruded lips, angulated mentolabial groove and a prominent chin. During the Renaissance, proportion was looked for in sense of beauty. Leonardo, observing the roman architect Marcus Vitruvius, developed the Vitruvian man, were the human body proportions were stablished. This figure uses the golden proportion, described by Pythagoras and Euclid, which represent a mathematical cadence known as Fibonacci sequence (XII). That sequence represents a geometrical shape (Fibonacci helix which can be founded within the nature and of course, the human body. Nowadays, this trend is followed, and aesthetical changes are pursued in order to satisfy our patients, having said that, we must also consider the content and not only the image. The professional’s opinion must be the first thing to consider, always having in mind the beauty concepts of the moment.  3. CLINICAL FACIAL ANALYSIS Before tracing planes and measuring, we must analyze the patient’s face and what feeling it gives to us. ¿Long or short? ¿Asymmetric? ¿Prognathic or retrognathic? On the other hand, the function has to be evaluated too and the facial symmetry. It can be possible that the patient does some gesture to hide an imperfection and when speaking it is possible to see that imperfection. There are five features to be analyzed during the facial analysis. They are part of the success of the treatment results. Age, race, gender, body habit and personality. AGE Ageing is something unavoidable and irreversible that happen to us. In humans, these modifications include tissue flexibility reduction, subcutaneous tissue fat reduction, collagen reduction, etc. For that reason, the skin starts to fold, and wrinkles appear, this provokes a facial proportion change which moves the hairline point backward, the nasal edge falls, the teeth are lost, and the fat tissue become dystrophic which makes noticeable the facial skeleton. The ageing signs appear from 30 years old, that implies that many of the patients desire to start and orthodontic or surgical treatment. RACE Humas races distinguish people from its physical and genetical features (skin colour, physical appearance and skin features). This aspect seems to be essential when analyzing the facial proportions. Watkins y Lubit (1992), conducted a study within 25 black race patients and they affirmed that soft tissues profile changes are unpredictable, and their profile ethnic features observed was the profile convexity reduction. Roland Song Teca and James D Smith (1999) observed 100 of Chinese random woman and their facial aesthetic proportions were analyzed through photography. One of the main results obtained was a 93,3º mentocervical angle, which means an increasement when comparing with Caucasian person (87,5º). This result is due to the less chin projection. Moreover, the nasofrontal angle in Chinese woman was bigger. GENDER Between man and woman there are different facial features, for instance, the nose. Men have a prominent supraorbital ridge, lower eyes and a cephalic size bigger than women. On the other hand, the woman face is rounded, with bend lines while men have stronger and angulated complexions. CORPORAL FEATURES There is a relationship between facial appearance and corporal habits. Person with a corporal medium size, short and with short arms tend to show a wider and rounded face, with a small and broad nose. On the other hand, long people, tend to have longer faces with a big and slim nose. PERSONALITY The facial expression gives us the individual overview, through facial signs, it could be possible to judge the personality. Not only the oral language gives us the power to communicate, but also the mimic allows humans to express feelings, desires, tends, happiness, sadness, fury, surprise or fear. 4. FACIAL PATTERNS. FRONTAL AND PROFILE ANALYSIS. FACIAL PROFILE LINE AND ANGLE MEASURES. LIP ANALYSIS. These points are needed in order to evaluate and analyze x-rays (lateral teleradiography, CT, etc.), photographical and clinical studies and after that, do the cephalometric analysis based in lines and standard mathematical universally accepted measures. Nowadays, computers have improved the facial proportion study. Some points and planes are used as the analysis reference. Some of the soft tissue landmarks: - Trichion (Tr) is the point in midsagittal plane where the hairline starts. - Soft tissue Glabela (G’) is the most prominent part in the midline between brows. - Nassion (N’) lies at the root of the nose in the midline. The deeper part where the frontal skin meets the nose root. - Subnasale (S) is the junction of the columella and upper cutaneous lip. - Supramentale (Sm) or B’ is midpoint of the labiomental crease between the lower lip and chin. - Pogonion (Pog’) is the most anterior point of the chin. - Menton (Me’) is the most inferior point of the chin. The Frankfurt horizontal plane (FHP) is found by drawing a line from the superior aspect of the external auditory canal to the most inferior point of the orbital rim while the patient’s eyes are parallel to ground. Vertical fifths: It is important to highlight that perfect symmetry degree doesn’t exist in most of the people. In midsagittal plane, the canon of facial proportion divides the face vertically into fifths, with the width of each eye (that means that the eye size is the fifth part of a face), the intercanthal distance and the nasal width all measuring one-fifth. If a line is traced from the lateral eye cantus, it can be seen that it goes near to neck, for that reason, the neck thickness is more or less the same as the distance between both lateral eye cantus. Horizontal thirds: The face is divided into horizontal thirds. The upper third extends from the hairline (Trichion) to the Glabella, the middle third from the glabella to the Subnasale, and the lower third from the Subnasale to the Menton. There are some irregularities in where the hairline starts (because of ageing and alopecia) and most of orthodontists exclude the upper third from their analysis and they consider from Nasion to Subnasale (which represents nasal heigh 43%) and from Subnasale to Menton (which represents the lower third 57%). - Forehead: it corresponds to the upper third which extends from the eyebrows to the hairline. In a profile sight, it is slightly convex (although it can be plane or protuberant). - Eyebrows: they make a curve arch with hair above the eyes. In woman it is located above the supraorbital edge while in man lies on it. If a line is traced from the nose cantus groove to the external eye cantus and goes perpendicular to a parallel line through the palpebral groove, we got the eyebrows beginning, and they finish in a drawn line from the external nose cantus groove to the external eye canthus. The beginning and the end of the eyebrows should be in a horizontal plane and its highest point is in the drawn line tangential to the lateral limbus. - Eyes: they are smaller in men, its width is the fifth part of the face, thus the distance between both eyes is the same as its width. If that distance increases,  there exist a telecanthus. The lateral eye cantus is higher than the medium one. The eyelid fold is from 7 to 15 mm to the eyelashes line. In a neutral sight the upper eyelid covers the iris area without covering the pupil and the lower eyelid (which is 1-2 mm to iris). - Nose: it is a facial aesthetical unit that can be divided into: o Nasal dorsum o Lateral sides o Nasal wing o Nasal tip o Soft triangles o Columella This lines and angles are interrelated, which allow us to analyse the facial aesthetic. Powell provided a detailed analysis of facial contours, proportions, and angles on profile. Nasofacial relationship includes 4 angles - Nasofrontal Angle: the angle formed by lines from the Nasion to the Glabella and from the Nasion to the nasal tip (From nose to forehead). The ideal ranges in Caucasians are 115-130º and it depends on the Glabella point prominence which varies between persons (is considered the less important). - Nasolabial angle: the angle formed between a line from the anterior Columella and Subnasale and a line from the Subnasale to the mucocutaneous border or the upper lip. In women is between 95º-100º and in men is 90-95º. - Nasofacial angle is formed between the anterior facial plane (Glabella to Pogonion) and the line tangent to the dorsum of the nose (a line from the nose dorsum tip to Nasion). This angle gives us the information about the nasal projection with the patient profile. The ideal ranges in Caucasians are 30-40º. 30 for women and 40 for men.  - Nasomental angle lies between the line along the dorsum to the Nasion and the line drawn from the nasal tip to the Pogonion. This is the most important one from the aesthetical Powell’s triangle. The ideal ranges in Caucasians are 120-132º and it relates the nose with the chin. Nose types: There are also multiple nose types and thus, classifications. Considering the ethnic parameters, there are three groups: Caucasian nose (a), mix race nose (b) and black nose (c). Simon’s ratio: In order to quantify the nasal tip projection, the Simon ratio can be used. It is found by dividing the length from the Subnasale to the nasal tip by the length from the Subnasale. to the superior labium. The ratio is 1:1. If we see the patient’s profile, the columella must be seen from 3-4 mm. Lips: - They are in the lower third of the face - The upper one is measured from Subnasale point to the upper free edge of them. The lower one goes from the lower edge to soft tissue Menton. - The position and shape are given from a true vertical line which is a perpendicular line to Frankfurt that goes through Subnasale: o The upper one must be between 2-5 mm forward that line. o The lower one 0-3 mm forward that line. o Soft tissue Pogonio must be between -4 and 0 mm regarding this line. Chin: The ideal chin position goes through a line from nasion perpendicular to the Frankfurt plane. In women, chin must be backward to this line. Neck: Teenagers’ neck must have a defined mandible and a harmonic cervicofacial groove. The mentocervical angle is formed with two lines, one goes from Glabela to soft tissue Pogonio (anterior facial plane), this line must cut a tangent line which goes from cervical (C) to soft tissue Menton. Its value goes from 80-95º. 5. DENTAL EXPOSURE. DENTOLABIAL ANALYSIS - Repose incisor exposure: from 1-5 mm depending on age (it wears away 3.37 in young adults, 1.26 adults) and gender (3.37 women and 1.91 men). In normal situation, the younger patients show more teeth in repose, also women show more teeth in repose than men. - Incisor edge: the convex incisor curve is parallel to the natural concavity of the lower lip. Symmetry offers a nice smile, usually in young people. The relationship between both curves can be without contact, with contact or covered. If than line is plane or inverted, is less attractive and the convexity will be an aesthetical objective and also a functional one. The incisor profile must be inside the lower lip to allow the correct lip closure. - Smile line: Teeth must be shown while smiling. It can be low (75%), medium (75-100%) and high (gummy smile). A band of 3-4 mm of soft tissue will be considered as a gummy smile. Treatment options must be based on the aesthetical features and the functional ones: - Repose incisor exposure - Smile tooth exposure. - Upper incisor position within the lower lip. - Phonetical trials. - Tooth size and proportion. - Anterior guides. - Root shape and length. - Periodontal support tissues. Other factores must be taken into consideration for the smile analysis as: - Smile width: every anterior tooth must be shown with premolars and even first molars. - Buccal corridors: the space shown while smiling within the buccal maxillary part to the mouth corners. It can be normal, wide or nil. - Interincisors line: it must be studied the alignment between this line located at the midpoint between central incisors) and the lip midline. They are misaligned ina 30% of the cases. - Occlusal plane: from a lateral position, it must be parallel to Camper plane (from lower frontier to the nose wing), up to 10º to Frankfurt. The incisor plane is the anterior proportion of the occlusal one.