DENT 4005 Orthodontics II: Etiology of Orthodontic Anomalies PDF

DENT 4005-ORTHODONTICS II Etiology of the Orthodontic Anomalies General Factors Lect. Kubra SUCU, DDS Bahçeşehir University School of Dental Medicine Department of Orthodontics [email protected] References Contemporary Orthodontics William R. Proffit Elsevier Etiology of Malocclusion Ge...

DENT 4005-ORTHODONTICS II Etiology of the Orthodontic Anomalies General Factors Lect. Kubra SUCU, DDS Bahçeşehir University School of Dental Medicine Department of Orthodontics [email protected] References Contemporary Orthodontics William R. Proffit Elsevier Etiology of Malocclusion General Factors What does etiology mean? ETIOLOGY the cause, set of causes, or manner of causation of a disease or condition. Etiology of Malocclusion General Factors The orthodontic speciality deals with treatment of various maloclusion. Etiology of the malocclusion is the study of its cause or causes. Etiology of Malocclusion General Factors Why we study etiology? In orthodontic treatment, the first step is elimination of the etiology Persistence of the etiology is one of the major causes of post-treatment relapse Etiology of Malocclusion General Factors Compherensive orthodontics management involves identification of the possible etiology factor and attempt to eliminate the same. Etiology of Malocclusion General Factors What causes malocclusion? Interaction of genetic and environmental factors Although it is difficult to know the precise cause of most malocclusions, we do know in general what the possibilites are, and these must be considered when orthodontic problems are being evaluated. Etiology of Malocclusion General Factors . Etiology of Malocclusion General Factors Etiology of Malocclusion can be classified into: -General factors -Local factors Or -Skeletal factors -Soft tissue factors -Local or dental factors -Habits Etiology of Malocclusion General Factors General Factors 1-Hereditary 2-Congenital 3-Environmental 4-Predisposing metabolic, climate or disease 5-Dietary problems 6-Habits 7-Posture 8-Trauma and accident Etiology of Malocclusion General Factors 1-Hereditary The child is a product of parents who have dissimilar genetic make up. Thus the child may inherit conflicting trait from both parents resulting in dentofacial deformity Some features are thought to be inherited such as; *Tooth size *Arch dimension *Overjet *Abnormality in teeth number Etiology of Malocclusion General Factors • Hereditary • • Two Facts • • 1. For each individual there is a basic pattern or blueprint for dentofacial development which may be masked but not really changed (unless by surgery). • • 2. Racial and familial characteristics repeat Etiology of Malocclusion General Factors Affected by Hereditary • Tooth size . • Arch length and width • Height of the palatal vault • Crowding or spacing • Overbite and overjet • Position and configuration of muscles • Tongue size and shape • Character of the oral mucosa Etiology of Malocclusion General Factors Heredity also plays a role in: . • Congenital deformities • Facial asymmetry • Size and position of the jaws • Oligodontia and anodontia • Supernumerary teeth • Variations in tooth shape Etiology of Malocclusion General Factors . Heredity Facial asimmetry Heredity Oligodontia and Anodontia Oligodontia refers to a lack of more than six teeth, excluding third molars Anodontia refers to a complete absence of teeth in one or both dentitions. B Heredity Supernumerary teeth are teeth present in addition to the normal complement. Mesiodens: The most common supernumerary tooth appears in the maxillary midline and is called a mesiodens. Heredity Supernumerary teeth Paramolar is a supernumerary molar usually small and rudimentary, most commonly situated buccally or palatally to one of the maxillary molars. Heredity Tooth shape If the tooth smaller than the normal; we call this thooth as microdontia. Heredity Tooth shape If the tooth bigger than the normal, we call it as macrodontia. Etiology of Malocclusion General Factors 2-Congenital These are malformation seen at the time of birth. Can results from several factors including chemicals, radiation, infections. Example; Cleft lip and palate Etiology of Malocclusion General Factors • Congenital Defects: They are malformations seen at the time of birth. . • Examples of Congenital Defects • • Clefts of the lip and palate • • Cerebral Palsy • • Crouzon’s syndrome • • Cleido-Cranial Dysostosis • • Cranial Synostosis Etiologies of the Orthodontic Anomalies General Factors Genetic and epigenetic Factors Congenital Defects: Crouzon’s Syndrome • Underdevelopment of the midface • Eyes that seem to bulge from their sockets • This syndrome arises because of prenatal fusion of the superior and posterior sutures of the maxilla along the wall of the orbit. Etiologies of the Orthodontic Anomalies General Factors Genetic and epigenetic Factors Congenital Defects: • Surgical treatment is required to open the fused sutures in these patients. • Retruzive maxilla. Etiologies of the Orthodontic Anomalies General Factors Genetic and epigenetic Factors Congenital Defects: • Results of Surgery & orthodontics Etiologies of the Orthodontic Anomalies General Factors Genetic and epigenetic Factors Congenital Defects: • Results of Surgery & Orthodontics Etiologies of the Orthodontic Anomalies General Factors Genetic and epigenetic Factors Congenital Defects: • Results of Surgery & Orthodontics • hypoplasic maxilla • reverse overjet • narrow maxilla • crowding. Etiologies of the Orthodontic Anomalies General Factors Genetic and epigenetic Factors Congenital Defects: Clefts of the lip and palate It is one of the most common malformations in the craniofacial region. Treatment requires teamwork. • -Orthodontics • -prosthodontics • -Pedodontics • -Plastic surgery • -anesthesiology • -Speech therapy Etiologies of the Orthodontic Anomalies General Factors Genetic and epigenetic Factors Maxilla is hypoplasyc and because of this, skeletally class 3 relationship is occur. Skeletal class III relationship Etiologies of the Orthodontic Anomalies General Factors Genetic and epigenetic Factors Congenital Defects Cleido-Cranial Dysostosis • An absence, or hypoplasia of the clavicles • • • Delayed ossification of the skull The presence of frontal bossing and midface hypoplasia Shortening of the long bones of the axial skeleton and digits (brachydactyly). • Retained deciduous teeth; • Multiple supernumerary teeth; and • Failure of eruption affecting the permanent dentition. Etiologies of the Orthodontic Anomalies General Factors Genetic and epigenetic Factors Congenital Defects Cleido-Cranial Dysostosis • Supernumarary teeth and • Failure of eruption affecting the permanent dentition Etiologies of the Orthodontic Anomalies General Factors Genetic and epigenetic Factors Congenital Defects Cerebral Palcy • This is a condition where in the patient lacks muscular coordination. • It uncontrolled and aberant and muscle activity upsets the muscles the balance resulting malocclusion. Etiology of Malocclusion General Factors 3-Environmental Can be classified into: Prenatal factors -Abnormal fetal posture -Maternal diet -Maternal ilness Post natal factors Forceps delivery Cerebral palsy Childhood trauma Etiology of Malocclusion General Factors 3-Environmental Prenatal • trauma • maternal diet • maternal metabolism & diseases • fetal posture • maternal consumption of alcohol & drugs Etiology of Malocclusion General Factors 3-Environmental Prenatal • trauma Prenatal intrauterine trauma is often associated with hypoplasia of the mandible and even facial asymmetries. • maternal diet • maternal metabolism & diseases • fetal posture • maternal consumption of alcohol & drugs Etiology of Malocclusion General Factors 3-Environmental Prenatal • trauma • maternal diet • maternal metabolism & diseases • fetal posture • maternal consumption of alcohol & drugs Etiology of Malocclusion General Factors 3-Environmental Prenatal • trauma • maternal diet • maternal metabolism & diseases • fetal posture • maternal consumption of alcohol & drugs Etiology of Malocclusion General Factors 3-Environmental Postnatal • Birth injuries • TMJ injuries • Accidents, fractures • Avulsion or displacement of teeth • Birth injuries • TMJ injuries Etiology of Malocclusion General Factors 3-Environmental Postnatal • Birth injuries • TMJ injuries • Accidents, fractures. :After an injury, if there is enough scarring around the TM joint to restrict translation of the condyle, so that the mandible cannot be pulled forward as much as the rest of the growing face, subsequent growth will be restricted. • Avulsion or displacement of teeth Accidents/ Fractures mandibular asymmetry Etiology of Malocclusion General Factors 4-Predisposing metabolic, climate or disease -Endocrine imbalance -Metabolic disturnances -Infectious disease Etiology of Malocclusion General Factors 4-Predisposing metabolic, climate or disease • Acute febrile disease – e.g. measles, mumps, chicken pox, etc. • Diseases of muscle dysfunction – e.g. muscular dystrophy, cerebral palsy, polio. • Endocrine disorders – e.g. pituitary, thyroid, parathyroid. Etiology of Malocclusion General Factors 5-Dietary problems Nutritional deficiency • Diet • Poor diet may cause deficiency diseases such as ricketts, beri beri, scurvy etc. • These may cause severe malocclusion due to interference with craniofacial growth and development in addition to Periodontal problems associated with significant bone loss. 6-Habits Etiology of Malocclusion General Factors • Habits • • Thumb or finger sucking • • Foreign objects • • Tongue thrusting • • Lip or cheek biting • • Mentalis muscle strain Etiology of Malocclusion General Factors 7-Posture • Not an important factor • • May be a contributing factor • • Seldom considered a primary cause Etiology of Malocclusion General Factors 7-Posture -Poor postural habits are said to be a cause for malocclusion -They may be associated with abnormal pressure and muscle imbalance therby increasing the risk of malocclusion -Children who support their head by resting chin on their hand and those who hand their head so that the chin rests against the chest are observed to have mandibular deficiency Etiology of Malocclusion General Factors 8-Trauma and accident Children are highly prone to injuries of the dento-facial region during the early years of life when they learns to crawl, walk or during play. Thank you...