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8/10/2019 Frequency of Malocclusion and Analyzation of Associated Risk
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FREQUENCY OF
MALOCCLUSION ANDANALYZATION OF
ASSOCIATED RISK FACTORS
UNDER SUPERVISION OF DR.FURQAN AHMED
MEMBERS:
KHALIDA FASEEH
MARRIAM KHAN
ZUMER NAYYERAMAL SAJID
AYESHA ASIF
YUSRA MASOOD
KARACHI MEDICAL AND DENTAL COLLEGE
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INTRODUCTION:
Occlusion is the relationship among all the components of masticatorysystem in their function,parafunction and dysfunction, whereas occlusionwhich is aesthetically and functionally not acceptable is referred to asmalocclusion.1.Ideally, all upper teeth fit slightly over the lower teeth. Thepoints of the molars fit the grooves of the opposite molar.The upper teethkeep the cheeks and lips from being bitten and the lower teeth protect thetongue.2.The term malocclusion encompasses all deviations of the teethand jaws from normal alignment,including a number of distinct conditions,like discrepanciesbetween tooth and jaw size (crowding andspacing),malrelationships of the dental arches (sagittal,transverse, andvertical) and malpositioning of individualteeth.3.There are differentcategories of malocclusion.
Class 1 malocclusion is the most common. The bite is normal, but the upperteeth slightly overlap the lower teeth.
Class 2 malocclusion, called retrognathism or overbite, occurs when theupper jaw and teeth severely overlap the bottom jaw and teeth.
Class 3 malocclusion, called prognathism or underbite, occurs when thelower jaw protrudes or juts forward, causing the lower jaw and teeth tooverlap the upper jaw and teeth.4.
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Symptoms
Abnormal alignment of teeth
Abnormal appearance of the face
Difficulty or discomfort when biting or chewing Speech difficulties (rare) including lisp
Mouth breathing (breathing through the mouth without closing the lips)
Signs and tests
Most problems with teeth alignment are discovered by a dentist during aroutine exam. The dentist may pull your cheek outward and ask you to bitedown to check how well your back teeth come together. If there is anyproblem, the dentist will usually refer you to an orthodontist for diagnosisand treatment.
Dental x-rays
head or skull x-rays.5.
Methods of recording and measuring malocclusion can be broadly divided
into two types i.e. qualitative and quantitative.6.while the severity or theextent to which a malocclusion deviates from the normal or ideal occlusioncan be quantified by using an occlusal index.7. Among the qualitativemethods of recording malocclusion Angles method of classifyingmalocclusion with or without modifications is probably the most widely
used.6.
http://umm.edu/~/ADAM/117/1/003801.ashxhttp://umm.edu/~/ADAM/117/1/003801.ashxhttp://umm.edu/~/ADAM/117/1/003802.ashxhttp://umm.edu/~/ADAM/117/1/003802.ashxhttp://umm.edu/~/ADAM/117/1/003802.ashxhttp://umm.edu/~/ADAM/117/1/003802.ashxhttp://umm.edu/~/ADAM/117/1/003802.ashxhttp://umm.edu/~/ADAM/117/1/003802.ashxhttp://umm.edu/~/ADAM/117/1/003801.ashxhttp://umm.edu/~/ADAM/117/1/003801.ashxhttp://umm.edu/~/ADAM/117/1/003801.ashxhttp://umm.edu/~/ADAM/117/1/003801.ashx8/10/2019 Frequency of Malocclusion and Analyzation of Associated Risk
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Cephalometric indicators are used to analyze the maxillary and mandibular skeletal
positions. Both angular and linear measurements have been proposed in theassessment of anteroposterior jaw-base relationships.8.Angles classification ofmalocclusions is universally accepted because of its simplicity as a method of
description and communication between dental professionals. Based on the
relationship of the mandibular first molars to the maxillary first molars, this system characterizes the
Class II malocclusions as having a distal relationship of the mandibular teeth relativeto the maxillaury teeth of more than one-half the width of the cusp. Two distinct typesof Class II malocclusion
exist, differing in the inclination of the maxillary central incisors. Class II Division 1malocclusions exhibit labially inclined maxillary incisors, an increased overjet with avertical incisor overlap varying from a deep overbite to an openbite and the Class IIDivision 2 malocclusion showing excessive lingual inclination of the maxillary centralincisors accompanied by a deep overbite and minimal overjet. An Angles Class IIImalocclusion means that the mandibular first molar is anteriorly placed in relation tothe maxillary first molar. It is a symptomatic or phenotypic description that uses thefirst molars and canines as criteria, and it has nothing to do with the maxillary andmandibular skeletal bases.Class II molar relationship may occur
unilaterally, depicted or classified as a class II subdivision of the affected side[9] ora bilaterally Class II on both the sides which is a frequently occurring type ofmalocclusion out of these two.[10] Dental malocclusion is present in all societies butits prevalence varies. There have been several studies investigating the prevalenceof various dentofacial characteristics11-15 but only a few have been conducted on anorthodontic
population.16,17There is a high incidence of Class I malocclusion in White Americans(Class I 52.5%, Class II 42.4% & Class III < 5%). Class I malocclusion is also moreprevalent in Black Americans (Class I 71%, Class II 16% & Class III 8.4%).
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There are a number of publications that prove the influence of genes on the
development of dentofacial system.18. The environmental factors include
forces and pressures from soft tissues and muscles surrounding the dentalarches, various habits (thumb sucking, nailbiting,etc.), and the effect oforthodontic appliances.19,20,21. The dentofacial system is also influenced bythe forces resulting from mastication.21,22. Therefore, although the majority ofthe etiological factors are clear,malocclusion are one of the most urgentstomatological problems. Individuals with Down syndrome (DS) andcerebral palsy (CP) are particularly prone to orofacial disorders.23.
Children with DS and CP have the habit of projecting the tongue against theteeth and out of the mouth and suffer frequent episodes of upper airwayinfection, which leads to a greater prevalence of mouth breathing andmalocclusion.24.
Children with the habit of maintaining their mouth open exhibit abnormaloromuscular movements and respiration, which compromises thecoordination and articulation of the lips and cheeks during speech and
swallowing.25 Oral habits and pressure on teethor
the maxillaand mandibleare etiologicalfactors in malocclusion.[26,27]
http://en.wikipedia.org/wiki/Toothhttp://en.wikipedia.org/wiki/Maxillahttp://en.wikipedia.org/wiki/Human_mandiblehttp://en.wikipedia.org/wiki/Etiologyhttp://en.wikipedia.org/wiki/Etiologyhttp://en.wikipedia.org/wiki/Human_mandiblehttp://en.wikipedia.org/wiki/Maxillahttp://en.wikipedia.org/wiki/Tooth8/10/2019 Frequency of Malocclusion and Analyzation of Associated Risk
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In theactive skeletalgrowth,[28]]mouthbreathing, fingersucking, thumbsucking, pacifiersucking, onychophagia(nailbiting), dermatophagia, penbiting, pencilbiting, abnormalposture, deglutitiondisorders and otherhabits greatly influence the development of the faceand dentalarches.[29][30][31][32][33]
Prolonged use of a bottle
Extra teeth, lost teeth, impacted teeth, or abnormally shaped teeth
Ill-fitting dental fillings, crowns, appliances, retainers, or braces Misalignment of jaw fractures after a severe injury
Tumors of the mouth and jaw
Sociodemographic facrtors
Dental caries
Periapical inflammation.
The aim of this study was to determine the frequency/prevalence ofmalocclusion and to analyze the risk factors associated with malocclusion in
different age groups in a local samples of patients seeking dental treatment.data
for this study was retrived from the patients who sought dental treatment at dental
O.P.D in Karachi Medical & Dental College.
http://en.wikipedia.org/wiki/Skeletalhttp://en.wikipedia.org/wiki/Human_development_(biology)http://en.wikipedia.org/wiki/Malocclusionhttp://en.wikipedia.org/wiki/Malocclusionhttp://en.wikipedia.org/wiki/Mouthbreathinghttp://en.wikipedia.org/wiki/Fingerhttp://en.wikipedia.org/wiki/Thumbhttp://en.wikipedia.org/wiki/Pacifierhttp://en.wikipedia.org/wiki/Nail_bitinghttp://en.wikipedia.org/wiki/Nail_(anatomy)http://en.wikipedia.org/wiki/Dermatophagiahttp://en.wikipedia.org/wiki/Penhttp://en.wikipedia.org/wiki/Pencilhttp://en.wikipedia.org/wiki/Human_positionhttp://en.wikipedia.org/wiki/Deglutitionhttp://en.wikipedia.org/wiki/Facehttp://en.wikipedia.org/wiki/Dental_archeshttp://en.wikipedia.org/wiki/Dental_archeshttp://en.wikipedia.org/wiki/Malocclusionhttp://en.wikipedia.org/wiki/Malocclusionhttp://en.wikipedia.org/wiki/Malocclusionhttp://en.wikipedia.org/wiki/Malocclusionhttp://en.wikipedia.org/wiki/Dental_archeshttp://en.wikipedia.org/wiki/Dental_archeshttp://en.wikipedia.org/wiki/Facehttp://en.wikipedia.org/wiki/Deglutitionhttp://en.wikipedia.org/wiki/Human_positionhttp://en.wikipedia.org/wiki/Pencilhttp://en.wikipedia.org/wiki/Penhttp://en.wikipedia.org/wiki/Dermatophagiahttp://en.wikipedia.org/wiki/Nail_(anatomy)http://en.wikipedia.org/wiki/Nail_bitinghttp://en.wikipedia.org/wiki/Pacifierhttp://en.wikipedia.org/wiki/Thumbhttp://en.wikipedia.org/wiki/Fingerhttp://en.wikipedia.org/wiki/Mouthbreathinghttp://en.wikipedia.org/wiki/Malocclusionhttp://en.wikipedia.org/wiki/Malocclusionhttp://en.wikipedia.org/wiki/Human_development_(biology)http://en.wikipedia.org/wiki/Skeletal8/10/2019 Frequency of Malocclusion and Analyzation of Associated Risk
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METHODOLOGY:
This cross-sectional study included patients who visited the Dental OPD, at
Karachi Medical And Dental College,Karachi, from June 2002 to April 2004.
Information regarding age and sex was obtained from the patients record
files. Both males and females were included in this study.
The inclusion criteria for the sample includes those with:
1.Presence with first permanent first molars.
2.Pre-treatment.
3.Orthodontic patients and patients seeking periodontal and operative
treatment.
The exclusion criteria includes patients with:
1.Significant past medical history.
2.Previous orthodontic treatment.
3.Previous prosthodontic treatment.
4.History of maxillofacial and plastic surgery.
5.Mixed dentition.
6.Congenital malformation.
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Patients were clinically examineed and were labelled under the
categories based on Angles classification, Occlusal index andIncisors classification.
ANGLES CLASSIFICATION:Angles classificaion categorizes as follows:
CLASS 1: A normal molar relationship exists but there is
crowding, misalignment of the teeth, cross bites, etc.
CLASS 11: Class II Malocclusion has two divisions to
describe the position of the anterior teeth. Class II Division 1 is when the maxillary anterior teeth are proclined anda large overjet is present.
Class II Division 2 is where the maxillary anterior teeth areretroclined and a deep overbite exists.
CLASS 111: A malocclusion where the molar relationship showsthe buccal groove of the mandibular first molar mesialy positioned tothe mesiobuccal cusp of the maxillary first molar when the teeth arein occlusion.
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INCISORS CLASSIFICATION:
Incisors were classified according to British Standard Institute (BSI) ofincisor classification.
Class Ithe lower incisal edges occlude with or lie immediately below thecingulum plateau of the upper incisors.
Class IIthe lower incisor edges lie posterior to the cingulum plateau ofthe upper central incisors.
Division 1- the overjet is increased, and the upper central incisors areproclined.
Division 2- the overjet is minimal or increased with retroclined upper centralincisors.
Class IIIthe lower incisor edges lay anterior to the cingulum plateau ofthe upper central incisors. The overjet is reduced or reversed.
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