Overview Of Orthodontics PDF

INTRODUCTION TO ORTHODONTICS DR. AISHA BATARINGAYA-SEKALALA BDS, MChD (Ortho)  WHAT IS ORTHODONTICS? It is that branch of dentistry concerned with facial growth, with development of the dentition and occlusion, and with the diagnosis, interception and treatment of occlus...

INTRODUCTION TO ORTHODONTICS DR. AISHA BATARINGAYA-SEKALALA BDS, MChD (Ortho)  WHAT IS ORTHODONTICS? It is that branch of dentistry concerned with facial growth, with development of the dentition and occlusion, and with the diagnosis, interception and treatment of occlusal anomalies.  SCOPE OF ORTHODONTIC TREATMENT Orthodontics only Removable appliances Fixed appliances Dento-facial orthopedics/Growth modification Growing patient Functional appliances (fixed or removable) Headgear Orthodontics combined with orthognathic surgery Younger patients: Distraction osteogenesis Adult patients: OGS POSTGRADUATE TRAINING IN ORTHODONTICS POSTGRADUATE SPECIALIST ORTHODONTIC TRAINING Is a period of general postgraduate training necessary before beginning specialist orthodontic training? How many years does specialist orthodontic training take? Is there a final examination at the end of specialist orthodontic training? Is there a special register?  MY EXPERIENCE Bachelor of Dental Surgery degree (five years). Work experience (five years). MChD Orthodontics (four years).  COURSE OUTLINE 4 years full time postgraduate training in: 1. Osteology and embryology of the craniofacial skeleton. 2. Pre-clinical modules Laboratory skills in fabrication of removable & functional appliances, fixed treatment on the typodont. Growth and development of the craniofacial structures. Diagnosis and treatment planning 3. Techniques and treatment  QUALIFICATION REQUIREMENTS Written and oral examination on: Thorough knowledge of the orthodontic principles, diagnosis and treatment planning. Thorough knowledge of all treatment modalities & techniques. Treatment of orthognathic patients. Treatment of patients with craniofacial anomalies. Thorough knowledge of the controversies, current research and trends in orthodontics. Original research and its presentation in form of a thesis. Treatment and completion of a minimum of 100 patients and write-up of a minimum of 20 cases for examination. ORTHODONTICS 1  COURSE OBJECTIVES Growth and development of the craniofacial structures. Mechanisms and principles governing facial growth. Normal development of the dentition. Aetiology of a malocclusion. Examination, diagnosis and orthodontic treatment plan. Orthodontic treatment in the developing dentition Biological and biomechanical principles governing orthodontic treatment.  EXPECTED OUTCOMES At the end of this course, the student should be able to: Describe the relevance of Orthodontics to Dentistry Explain the mechanisms, principles and theories governing cranio-facial growth Explain the aetiology of malocclusions. Describe the growth and development of the calvaria, cranial base, maxilla and mandible Describe the normal development of the dentition. Explain the biology and biomechanics of orthodontic treatment Describe the orthodontic treatment carried out in the mixed dentition.  COURSE OUTLINE Craniofacial growth and development Mechanisms, principles and theories of cranio-facial growth The aetiology and classification of malocclusion The normal development of the dentition Examination and treatment planning for the orthodontic patient Cephalometric analysis and skeletal maturity indicators Preventive and interceptive treatment The biology and biomechanics of orthodontic tooth movement  NEED FOR TREATMENT Until recently, baseline data on the occlusal traits in Uganda was unavailable. Knowledge of the frequencies of different occlusal anomalies is important so that we can better serve the needs of those who suffer from malocclusion.  NEED FOR TREATMENT… Risk-Benefit Analysis: Perceived benefits to the patient in terms of improved function and aesthetics balanced against the risks of appliance therapy and the prognosis of achieving aims of treatment.  NEED FOR TREATMENT… DENTAL HEALTH Caries Periodontal disease Trauma to the anterior teeth Masticatory function Speech Tooth impaction TMJ dysfunction syndrome  NEED FOR TREATMENT… PSYCHOSOCIAL WELLBEING Severe malocclusion has a negative effect on self-esteem Patient’s perception is influenced by cultural and racial diversity Research shows that an unattractive dentofacial appearance has a negative effect on the expectations of teachers and employers  DEMAND FOR TREATMENT Awareness of malocclusion and orthodontic treatment is greater in: Females Higher socio-economic families In areas of smaller population : orthodontist ratio With increased public awareness, there is: Increased demand for treatment Increased acceptability of orthodontic appliances Increase in adult patients Demand for a higher standard of treatment result INDEX O F O RT H O DO NT IC T R EAT M EN T N EE D ( I OT N) GROWTH  ORTHODONTICS & GROWTH Orthodontic treatment is often carried out on growing children. Growth of the different parts of the face and skull must harmonize if a normal growth pattern is to result. Orthodontic treatment may be aimed at growth modification. Clinicians must be aware of the impact of growth upon the timing, progress and outcome of treatment. Knowledge of growth is essential to understand the predictors for success, potential pitfalls, and stability of the finished result.  DETERMINANTS OF FACIAL GROWTH Growth is controlled by Genetic factors Environmental factors (nutrition, illness etc.) Malocclusion may be due to disproportion in jaw growth therefore mechanisms of skeletal growth important. GROWTH PATTERNS  GROWTH MOVEMENTS Deposition Resorption Cortical drift Displacement  MECHANISMS OF BONE GROWTH DEPOSITION & RESORPTION Deposition occurs on the surface facing the direction of growth while resorption occurs on the side facing away. Results in change of size, shape, proportion & relationship with other structures AREA RELOCATION Progressive sequential movement of component parts as a bone enlarges.  Growth Fields varying rates of growth of resorptive and depository fields Growth Site A growth field having a special role in the growth of a bone (Moyers) A location where growth is taking place (Proffit). Growth Centre A special area that somehow controls the growth of the bone (Moyers) Location at which independent (genetically controlled) growth occurs e.g. sutures, synchondrosis (Proffit). THE PHYSIOLOGICAL BASIS OF GROWTH & DEVELOPMENT PATTERNS OF GROWTH & DEVELOPMENT Cephalocaudal gradient of growth OCCLUSION  OCCLUSION Occlusion is defined as the interdigitation of maxillary & mandibular teeth. This description implies that occlusion is a static contact relationship of teeth. Occlusion involves the relationship of the teeth in centric occlusion, in centric relation, & during function. The practical concept of occlusion is to recognize the interplay between the teeth, TMJ & neuromuscular system.  OCCLUSION Within the distribution of occlusal forms are the conditions somewhat arbitrarily designated as ideal, normal & malocclusion, the precise differences of which are difficult to identify.  IDEAL & NORMAL OCCLUSION IDEAL OCCLUSION: § Refers to a perfect occlusion rarely seen in nature. NORMAL OCCLUSION: § Allows for minor deviation from the ideal that is aesthetically & functionally acceptable. § Is accepted to be a Class I molar relationship with good alignment of all the teeth.  MALOCCLUSION § Any deviation from the normal relation of the teeth in the same arch to each other and to the teeth in the opposite arch. Andrews Six Keys to Normal occlusion: Molar relationship, crown angulation, crown inclination, rotations, spaces, occlusal plane AETIOLOGY OF MALOCCLUSION  DEFINITION Aetiology is the science that deals with determination of the cause of an anomaly The "causes" of malocclusion are usually grouped because they are usually nonspecific and our knowledge is often imprecise.  AETIOLOGY OF MALOCCLUSION How long? At what age? Pre or post-natal? Continuous or intermittent? The aetiology of malocclusion is multifactorial & as such, a problem- oriented approach is the ideal management of orthodontic problems. DEVELOPMENT OF THE DENTITION  STAGES OF THE DENTITION PRIMARY DENTITION MIXED DENTITION From the eruption of the 1st permanent tooth (mandibular central incisor) to the time the last primary tooth is shed. PERMANENT DENTITION  PRIMARY DENTITION STAGE… 1. Overbite: >60% of children have reduced or open bite, often attributed to sucking habits 2. Overjet: Normal is 0-4mm, when excessive, its attributed to sucking habits 3. Spacing: May be generalized as in ⅔ of children Localized spacing can occur normally (primate spaces) Crowding is in 3% of children  TERMINAL PLANES Change from flush to Class I is by Use of the leeway space Differential growth of the mandible Differential movement of the lower molar  MIXED DENTITION STAGE From the eruption of the 1st permanent tooth (usually the Md central incisor) to the time the last primary tooth is shed. Incisor liability & Leeway space The difference between the amount of space needed for the incisors and the amount of space available for them is called incisor liability. The difference between the amount of space available for premolars & the amount of space needed to fit them is called leeway space.  DENTAL AGE Dental age is determined by: Which teeth have erupted Degree of resorption of roots of primary teeth Degree of development of permanent teeth. CLASSIFICATION OF MALOCCLUSION  ANGLE’S CLASSIFICATION Is most widely used Serves as an excellent means of general description Facilitates the communication about the malocclusion Describes A-P relationships of the permanent first molars.  ANGLE’S CLASSIFICATION Class I The mesiobuccal cusp of the maxillary 1st molar articulates in the mesio-buccal groove of the mandibular 1st molar with teeth in centric occlusion. Class II The mesiobuccal cusp of the maxillary 1st molar articulates mesial to the mesio- buccal groove of the mandibular 1st molar with teeth in centric occlusion. Class III The mesiobuccal cusp of the maxillary 1st molar articulates distal to the mesio- buccal groove of the mandibular 1st molar with teeth in centric occlusion. PREVENTIVE & INTERCEPTIVE ORTHODONTICS PREVENTIVE & INTERCEPTIVE ORTHODONTICS Preventive Orthodontics: The elimination of factors that may lead to malocclusion in an otherwise normally developing dentition. Interceptive Orthodontics: To intercept or correct malocclusions that would otherwise be maintained or become progressively more complex in the permanent dentition or result in skeletal anomalies. THE BIOLOGY OF TOOTH MOVEMENT  THE BIOLOGY OF TOOTH MOVEMENT The ability to move teeth within the bones of the jaws is the basis of orthodontic treatment. This movement relies on the ability of the bone to remodel around the moving tooth and periodontal ligament (PDL). VARIABLES AFFECTING OUTCOME OF TREATMENT Out of clinician’s control Growth Bone-periodontal-gingival responses Neuromuscular adaptation to jaw & tooth position In clinician’s control Magnitude & direction of forces, couples & moments Moment-to-force ratio exerted by the appliance  IS ORTHODONTICS WORTH IT????? It is sloooooooooooooow! If you want instant results, do prosthetics If you want steady progress, do orthodontics INSTA-DONTICS!!!! ORTHODONTICS!!!! THANK YOU!