Epidemiology of Malocclusion Dr.Nabil Al-Zubair


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Epidemiology of Malocclusion Dr.Nabil Al-Zubair

  1. 1. Epidemiology of Malocclusion Dr. Nabil Al-Zubair
  2. 2. The prevalence of malocclusions in modern populations
  3. 3. Orthodontic Anomalies of any kind and malocclusions are relative infrequently analyzed in bio-archaeological investigations There are at least three reasons for this
  4. 4. First:orthodontic anomalies andmalocclusions are not recognized bybioarchaeologists, anthropologists,and related scientists as an importantand useful source of data about theoral and general health of ancientpopulations, as well as an importantsource of data about other aspects oftheir everyday life ‫لم يتم التعرف على حاالت سوء اإلطباق بواسطة‬ ،‫علماء اآلثارالبيولوجية، علماء األنثروبولوجيا‬ ‫كمصدر مهم ومفيد من البيانات حول صحة الفم‬ ‫والعامة من الشعوب القديمة، وكذلك مصدرا‬ ‫مهما للبيانات عن الجوانب األخرى من حياتهم‬ ‫اليومية‬
  5. 5. Second:Scientists involved in the examination of skeletal remains derivedfrom archaeological contexts usually do not have enoughknowledge for the identification (diagnosis) of orthodonticanomaliesor for the interpretation of malocclusions ‫العلماء المشاركين في دراسة بقايا الهياكل العظمية المستمدة من‬ ‫سياقات األثرية عادة ليس لديهم ما يكفي من المعرفة لتفسير سوء‬ .‫اإلطباق‬ Dentists, as experts educated in the diagnosis and interpretations of orthodontic status are rarely involved in bio-archaeological investigations. .‫أطباء األسنان، وخبراء التشخيص نادرا ما يشاركوا في التحقيقات األثرية‬
  6. 6. Third: ‫حتى عندما يتم التعرف على أهمية تقويم األسنان، وأنها هي‬even when the importance of ‫محور التحقيق، وحتى لو أحد الباحثين هو طبيب أسنان، هناك‬orthodontic anomalies is recognised, ‫مشكلة هامة هي: عدم وجود عينات صالحة لالستعمال‬and they are a focus of theinvestigation, and even if one of theresearchers is a dentist, there is thefinal and possibly most importantproblem: the lack of usable samplesPapers and reports aboutmalocclusions and orthodonticanomalies in skeletal populationsfrom archaeological contexts arerelatively rare and often based onsmall samples
  7. 7. Although Malocclusion Now Generally Occurs In Much Of The Population, this was not always the case. Skeletal remains show that malocclusions were relatively unusual before the 19th and 20th centuries
  8. 8. However Malocclusions were not absentً‫اإلنسان البدائ‬ Neanderthal specimen CROWDING , although the estimated to be 100,000 Neanderthals had little rotation and years old displacement of teeth with close a proximal contacts ancient skull dated about Impacted maxillary canines 7250 to 6700 BC. congenitally missing third molars since Medieval Times Several reports found increases in ‫العصور الوسطى‬ the frequency of malocclusion the last 150 years increases in malocclusion frequency seem to have accelerated in modern industrialized societies , after only modest changes for 6000 years
  9. 9. Problems of Dental Public Health Caries Periodontal Malocclusion others disease Malocclusions are THIRD in the ranking of priorities among the problems of Currently dental public health worldwide, surpassed only by dental cavity and periodontal diseases with the reduction of caries in children and adolescents in recent decades,However, this condition has received more attention
  10. 10. ‫الدراسات االستقصائية‬ Many organized surveys have been carried out in different parts of the world with the objective of Estimating prevalence of malocclusion & orthodontic treatment needs The ultimate goal being to identify etiologic factors Prevalence is whensomething is widespread The total number of cases of a condition in a given population at a specific time
  11. 11. Prevalence of malocclusionCountry % of malocclusionChinese children 67.82Nigeria children 84 % Class I malocclusion 1.7 % Class II malocclusionIndian Children 19.6 %American 34 % whites 15 % blacks is estimated to be HIGHER in Developed countries > developing & under-developed countries
  12. 12. Measurement of malocclusionMalocclusion & dento-facial deformity are conditions that ‫تشكل خطرا على المحافظة على صحة الفم واألسنان‬ - Constitute a hazard to the maintenance of oral health - Interfere with the well being of the person by adversely affecting dento-facial aesthetics, mandibular function or speech
  13. 13. Measurement of malocclusion as a public health problem is extremely difficult since most orthodontic treatment is undertaken for AESTHETIC REASONS It is very difficult to estimate the extent to which malposed teeth or dento-facial anomalies constitute a psychological hazard ‫من الصعب للغاٌة تقدٌر المدى إلى أي حد ٌشكل سو اإلطباق مشكلة نفسٌة‬
  14. 14. Malocclusion has proved to be a difficult entity to define because individual perceptions of what constitute a malocclusion problem differ widely ‫تختلف التصورات الفردية فبما يعتبر مشكلة سو اإلطبلق على نطاق واسع‬As a result No generally accepted epidemiological index of malocclusion has yet been devised
  15. 15. Malocclusion is not an acute condition thereforeTreatment of malocclusion has been associated with a great degree of subjectivity and distorted perceptions of treatment need
  16. 16. EPIDEMIOLOGY OF MALOCCLUSION "‫"دراسة لديناميكية حدوث حالة أو سمة في مجتمع أو مجموعة‬ NHANES III USPHS survey • “study of the dynamics of occurrence of a (1989-1994) condition or trait in a population or (1963, 1969 &1970) group”14,000 individuals surveyed data on :provides current information Epidemiology 6 - 11 and 12 -17 year-on children, adults and major old childrenethnic groups
  17. 17. Current Malocclusion Prevalence DataNHANES III ( National Health And Nutrition Estimates Survey III) 1989-1994 Study design  14,000 individuals sampled  Target population of 150,000,000  Statistically designed weighted samples  75% Whites, 11% African Americans and 8% Hispanics
  18. 18. WHAT IS MALOCCLUSION?  Malocclusion is not a disease,but a spectrum representing biological variability/diversity  When the deviation from the normal reaches a certain degree of severity (threshold), then it is termed malocclusion  What is of relevance is “clinically significant” deviation from normal occlusion
  20. 20. 20% Mild 35% Normal 5% 20% 20% Moderate 20% Severe 20% 5% 20% HandicappedMalocclusion
  21. 21. A handicapping malocclusion DEFINITION: Abnormal dental development with at least one of the following:(a) A medical condition and/or a nutritional deficiency with medical physiological impact, that is documented in the physician progress notes that predate the diagnosis and request for orthodontics.The condition must be non-responsive tomedical treatment without orthodontictreatment. (b) The presence of a speech pathology, that is documented in speech therapy progress notes that predate the diagnosis and request for orthodontics. The condition must be non-responsive to speech therapy without orthodontic treatment.
  22. 22. (c) Palatal tissue laceration from adeep impinging overbite wherelower incisor teeth contact palatalmucosa.This does not include occasionalbiting of the cheek
  23. 23. COMPONENTS OF MALOCCLUSION Sagittal or Antero- posterior Vertical Transverse Intra-arch (crowding/spacing)
  24. 24. NHANES III TRAITS ‫الصفات‬ Irregularity index Midline Diastema (spacing) Posterior cross-bite (transverse) Overjet (antero-posterior) Overbite/ Openbite (vertical)
  26. 26. DIASTEMA
  27. 27.  Little more than 50% surveyed had little or no IRREGULARITY and DIASTEMA crowding with about 6-8 % exhibiting severe to extreme crowding in the younger age groupIrregularity increased between childhood and  26% had maxillary midline diastemas in theyouth, and was largely stable between youth 8-11 age group, which decreased to 6% inand adult EXCEPT for mandibular crowding later age groupswhich increased
  28. 28. ANGLE’S CLASSIFICATION – Antero-posterior componentClass I malocclusion Class II malocclusion Class III malocclusionANTERO-POSTERIOR COMPONENT
  29. 29. Antero-Posterior Dimension Class IIOverjet 8-11 yrs 12-17yrs 18-50 yrs10mm 0.2 0.2 0.47-10 3.4 3.5 3.95-6 18.9 11.9 9.13-4 45.2 39.5 37.7Ideal 1-2 29.6 39.3 43.0 Class III0 2.2 4.6 4.8-1 to -2 0.7 0.5 0.7-3 to -4 0 0.6 0.2-4 0 0 0.1
  30. 30. Antero-Posterior Dimension, By Ethnicity Class II Overjet EA AA Hispanic 10mm 0.3 0.4 0.4 7-10 3.8 4.3 2.2 5-6 10.1 11.8 6.5 3-4 38.0 39.8 49.0 Ideal 1-2 42.4 35.6 33.6 Class III 0 4.1 6.1 6.7 -1 to -2 0.5 1.5 0.9 -3 to -4 0.2 0.4 0.4 -4 0.1 0.1 0.3
  32. 32. PREVALENCE Vertical problems of anterior open bite versus anterior deep bite exhibits RACIAL DIFFERENCES Anterior open bites  Anterior deep bites affect significantly are more common larger number of in European- African-Americans Americans
  33. 33. SUMMARY OF PREVALENCE  30% had normal Class I occlusion  15-20% had Class II malocclusions  50-55% had Class I malocclusions (crowding)  Less than 1% had Class III malocclusions Class II malocclusions Normal Class I occlusion Class II problems were most prevalent in Class I malocclusions (crowding) people of European descent Class III problems were MORE prevalent in the African American, Hispanic and East Asian populations
  34. 34. For many years, Epidemiologic studies of malocclusion suffered from: considerable DISAGREEMENT among the investigators 100 % of malocclusionThe considerable variations 90in malocclusion frequency 80and treatment need relate to: 70- different ages, 60- genetics, 50- methods of registrations. 40- the size and composition 30 of the group studied (for example age and racial 20 characteristics), 10 0 1930 1945 1955 1965 Prevalence of malocclusion in the United States
  35. 35. Prevalence of crowding706050 Age= 13 n= 20040 Age= 13 Age= 10 -12 n= 20030 n= 47920 Age≥20 Age= 12 n=669 n= 574410 0 Libya Jordan Jordan Iraq (Max. (Mand. Iraq Sweden ant) (Max. (Mand. Sweden South ant) ant) Male Female ant) Africa
  36. 36. Mean overjet and prevalences of increased overjet16141210 mean OJ8 OJ ≥ 66420 Jordan America England Iraq
  37. 37. Evolution  There was a tendency to decreased size and number of teeth  Modern Humans have underdeveloped jaws  Imbalance between the progressive decreased jaw size and tooth size can lead to teeth crowding or spacing  Less use of masticatory forces with softer food could have lead to an increase in malocclusion
  38. 38. Need for orthodontic treatmentProtruding, IRREGULAR, or MALOCCLUDED TEETHcan cause three types of problems for the patient: ‫التمٌٌز‬ 1- Discrimination because of facial appearance 2- Problems of Oral functions and TMD 3- Greater susceptibility to trauma, periodontal disease, or tooth decay
  39. 39. • Psychological problems Malocclusion is likely to be a social handicap ‫ٌحتمل أن ٌكون عائقا اجتماعٌة‬ Well-aligned teeth and  Appearance makes a pleasing smile carry difference in teachers Positive Status to all expectations and therefore social levels student progress, in employment and in competition for a mate.  An individual who is grossly disfigured can anticipate a consistently Negative Response. ‫مشوه‬
  40. 40. • Oral functionSevere malocclusion can Compromise mastication as in open bite cases certain sounds might be impossible to be produced and patients usually need speech therapy (as in Cleft lip/palate patients) (Class III, anterior open bite, posterior cross bite and rotated/tipped teeth) correlate positively to TMDSo, Malocclusion + TMD may indicate the need for orthodontic treatment
  41. 41. Relationship to injury and Dental diseases  Malocclusion contributes to caries and periodontal disease by increasing the areas of food stagnation.  Trauma from occlusion due to improper alignment of teeth can cause periodontal diseases.  Protruded incisors as in Class II Division 1 malocclusion, can make the patient more prone to trauma than well-aligned incisors.
  42. 42. Epidemiologic estimate of orthodontic treatment need and demand: : ‫تقدير الحاجة والطلب إلى عالج تقويم األسنان‬ About 35 % of adolescents are perceived by parents and peers as needing orthodontic treatment Dentists recommend treatment for another 20% There is more orthodontic need in urban areas than in rural areas  Demand for orthodontic need is correlated to family income
  43. 43. Occlusal indices
  44. 44. Occlusal indicesDiagnostic Epidemiologic Treatment needs Treatment outcome Treatment complexity indices indices indices indices Index
  45. 45. Occlusal indicesDiagnostic Epidemiologic Treatment needs Treatment outcome Treatment complexity indices indices indices indices Index Dental esthetic DAI components include: index (DAI), Cons 1. Number of visible missing teeth (incisors, canines and premolars in (1986) maxillary and mandibular arch). 2. Incisal segment crowding 3. Incisal segment spacing 4. Midline diastema 5. Maxillary anterior irregularity 6. Mandibular anterior irregularity 7. Maxillary overjet 8. Mandibular overjet 9. Vertical anterior open bite 10. Anteroposterior molar relationship
  46. 46. Occlusal indicesDiagnostic Epidemiologic Treatment needs Treatment outcome Treatment complexity indices indices indices indices Index DAI score Severity levels Normal or minor malocclusion  25 No treatment need or slight need Definite malocclusion Treatment elective 26 – 30 Severe malocclusion Treatment highly desirable 31 – 35 Very severe (handicapping) malocclusion  36 Treatment mandatory
  47. 47. INDEX OF ORTHODONTIC TREATMENT NEED IOTN It has two components A. Dental health component (DHC): has five gradesGrade 1—none: variations in occlusionincluding displacement less than orequal to 1 mm.Grade 2—littleGrade 3—moderateGrade 4—greatGrade 5—Very great B. Esthetic component of IOTN
  48. 48. Dr. Nabil Al-Zubair