Classification of malocclusion

MOST OF CLASSIFICATION OF MALOCCLUSION OF TEETH WILL BE DISCUSSED

1. Classification
of
Malocclusion
Supervisor: Prof. Maher A. Fouda

2. • Introduction
• Individual tooth malpositions
• Malrelation of dental arches
• Skeletal malocclusions
• Angle's classification of malocclusion
• Dewey's modification
• Lischer'smodification
• Bennetle'sclassification
• Simon's classification
• Skeletal classification
• Ackerman-Profillsystem of classification
• Incisor classification

3. INTRODUCTION
Tounderstandagroupofidentitiesitis
advisabletodividethemintogroupsand
subgroupsbasedoncertainsimilarities.
Classificationofmalocclusionisthedescription
ofdentofacialdeviationsaccordingtoa
commoncharacteristic,ornorm.Various
classificationsareproposedbydifferent
researchersbasedontheirexperiencesand
dependinguponwhattheyfoundtobeclinically
relevant.

4. Theunderstandingoftheseclassificationsis
essentialforthestudentoforthodonticsas
theywouldbefrequentlyreferredtoduring
communicationsbetweenconsultantsand
sometimes,certainidentitieswithina
subgroupwillrequirethesametreatment
protocols.

5. Dependinguponwhichpartoftheoraland
maxillofacialunitisatfault,malocclusions
canbebroadlydividedintothreetypes:-
•Individualtoothmalpositions.
•Malrelationofthedentalarchesor
dentoalveolarsegments.
•Skeletalmalrelationships.

6. Thesethreecanexistindividuallyinapatientor
incombinationinvolvingeachother,
dependinguponwherethefaultlies-inthe
individualdentalarchorthedentoalveoJar
segmentsortheunderlyingskeletal
structure.

7. INDIVIDUAL TOOTH MALPOSITIONS
Thesearemalpositionsofindividualteethinrespecttoadjacent
teethwithinthesamedentalarch.Hence,theyarealsocalled
intra-archmalocclusions.Thesecanbeofthefollowingtypes:
MESIALINCLINATIONORTIPPING
Thetoothistiltedmesially,i.e.thecrownismesialtotheroot
(FigA).
Fig. A :Mesially inclined/tipped
central incisors. The long axis of
the teeth is depicted in black, with
the midline in white dots

8. DISTAlINCLINATIONORTIPPING
Thetoothistilteddistally,i.e.thecrownis
distaltotheroot(FigB).
Fig. B: Distally inclined maxillary right
lateral incisor. The long axis is depicted in
black, with the ideal inclination of the
tooth depicted by white dots

9. LINGUALINCLINATIONORTIPPING
Thetoothisabnormallytiltedtowardsthetongue(orthepalate
inthemaxillaryarch)(Fig.C).
Fig. c ; Palatally inclined maxillary left incisor and Lingually inclined mandibular second molars

10. LABIAUBUCCALINCLINATIONORTIPPING
Thetoothisabnormallyinclinedtowardsthe
lips/cheeks(FigD).
Fig.d :Labially inclined maxillary right central incisor

11. INFRA-OCCLUSION
The tooth is below the occlusal plane as
compared to other teeth in the arch (Fig. E).

12. SUPRAOCCLUSION
The tooth is above the occlusal plane as
compared to other teeth in the arch (Fig. F).
Maxillary central and mandibular
incisors are supraerupted
Supraerupted Maxillary anteriors

13. ROTATIONS
Thistermreferstotoothmovementsaroundthelongaxisofthetooth.
Rotationsareofthefollowingtwotypes:
MesiolingualorDistolabial
Themesialaspectofthetoothisinclinedlinguallyorinotherwords,thedistal
aspectofthecrownislabiallyplacedascomparedtoitsmesialaspect
(Fig..1G)
DistolingualorMesiolabial
Thedistalaspectofthetoothisinclinedlinguallyorinotherwords,themesial
aspectofthecrownislabiallyplacedascomparedtoitsdistalaspect(Fig.IH)

14. Transposition
Thistermisusedincasewheretwoteeth
exchangeplaces,e.g.acanineinplaceofthe
lateralincisor(Fig.I).
Transposition of the mandibular right canine
with the mandibular right lateral incisor

15. MALRELATION OF DENTAL ARCHES
Thesemalocclusionsarecharacterizedbyan
abnormaIrelationshipbetweenteethor
groupsofteethofonedentalarchtothatof
theotherarch.Theseinter-archmalrelations
canoccurinallthethreeplanesofspace,
namely-sagittal,verticalortransverse.

16. Theycanbeoftwotypes:
Pre-normalOcclusion
Wherethemandibulardentalarchisplacedmoreanteriorlywhentheteeth
meetincentricocclusion(Fig.A).
Post-normalOcclusion
Wherethemandibulardentalarchisplacedmoreposteriorlywhenthe
teethmeetincentricocclusion(Fig.B).
The mandibular arch is located more
posteriorly as compared to normal
The mandible is placed more anteriorly as
compared to normal

17. Theycanbeoftwotypesdependingontheverticaloverlapoftheteethbetween
thetwojaws.
DeepBite
Heretheverticaloverlapbetweenthemaxillaryandmandibularteethisin
excessofthenormal(Fig.A).
OpenBite
Herethereisnooverlaporagapexistsbetweenthemaxillaryandmandibular
teethwhenthepatientbitesincentricocclusion.Anopenbitecanexistinthe
anterior(Fig.B)ortheposterior(Fig.C)region.
Fig.B: Anterior open biteFig.A: Anterior deep bite
Fig. C: Posterior open bite due to the
presence of a lateral tongue thrust habit

18. Theseincludethevarioustypesofcrossbites.Generallythe
maxillaryteethareplacedlabial/buccaltothemandibular
teeth.Butsometimesduetotheconstrictionofthedental
archesorsomeotherreasonthisrelationshipisdisturbed,i.e.
oneormoremaxillaryteethareplacedpalatal/lingualtothe
mandibularteeth.Thesedifferinintensity,positionandthe
numberofteeththatmaybeinvolved.

19. Thesemalocclusionsarecausedduetothe
defectintheunderlyingskeletalstructure
itself.Thedefectcanbeinsize,positionor
relationshipbetweenthejawbones.

20. ANGLE'S CLASSIFICATION OF MALOCCLUSION
In1899,EdwardAngleclassifiedmalocclusionbasedon
themesial-distalrelationoftheteeth,dentalarchesand
jaws.Heconsideredthemaxillaryfirstpermanentmolaras
afixedanatomicalpointinthejawsandthekeyto
occlusion.Hebasedhisclassificationontherelationshipof
thistoothtootherteethinthemandibularjaw.Morethan
100yearshavepassedsinceAngleproposedhissystem
ofclassificationyet,itremainsthemostfrequentlyused
classificationsystem.Itissimple,easytouseandconveys
preciselywhatitwasconceivedfor,i.e.therelationshipof
themandibularteethwithrespecttothemaxillaryfirst
permanentmolar.

21. Angleclassifiedmalocclusionintothreebroad
categories.Itispresentedinaformthatismost
acceptedinthepresenttimes.Thethree
categoriesaredesignatedas"Classes“andare
representedbyRomannumerals-I,IIandIII.

22. Themandibulardentalarchisinnormalmesiodistalrelation
tothemaxillaryarch,withthemesiobuccalcuspofthemaxillary
firstmolaroccludinginthebuccalgrooveofthemandibularfirst
permanentmolarandthemesiolingualcuspofthemaxillary
firstpermanentmolaroccludeswiththeocclusalfossaofthe
mandibularfirstpermanentmolarwhenthejawsareatrestand
theteethapproximatedincentricocclusion.

23. Mandibulardentalarchandbodyareindistalrelation
tothemaxillaryarch.Themesiobuccalcuspofthe
maxillaryfirstpermanentmolaroccludesinthespace
betweenthemesiobuccalcuspofthemandibular
firstpermanentmolarandthedistalaspectofthe
mandibularsecondpre-molar.Also,themesiolingual
cuspofthemaxillaryfirstpermanentmolaroccludes
mesialtothemesio-linguaIcuspofthemandibular
firstpermanentmolar.

24. AngledividedtheClass-IImalocclusionsintotwo
divisionsbasedonthelabiolingualangulationofthe
maxillaryincisorsas:
ClassII-Division1:-
AlongwiththemolarrelationwhichistypicalofclassII
malocclusionsthemaxillaryincisorteethareinlabioversion.

25. ClassII-Division2:-
AlongwiththetypicalClassIImolar
relationship,themaxillaryincisorsarenear
normalanteroposteriorlyorslightlyin
linguoversionwhereasthemaxillarylateral
incisorsaretippedlabiallyand/ormesially.

26. ClassII-Subdivision:-
WhentheClassIImolarrelationshipoccurson
Onesideofthedentalarchonly,the
malocclusionisreferredtoasasubdivisionof
itsdivision.
Angle's Class II subdivision (Class I molars on the left side)

27. Themandibulardentalarchandbodyisinmesial
relationshiptothemaxillaryarch;withthemesiobuccal
cuspofthemaxillaryfirstmolaroccludinginthe
interdentalspacebetweenthedistalaspectofthe
distalcuspsofthemandibularfirstmolarandthe
mesialaspectofthemesialcuspsofthemandibular
secondmolar.

28. PseudoClassIII-Malocclusion:-
ThisisnotatrueClassIIImalocclusionbutthe
presentationissimilar.Herethemandibleshifts
anteriorlyintheglenoidfossaduetoapremature
contactoftheteethorsomeotherreasonwhenthe
jawsarebroughttogetherincentricocclusion.

29. ClassIII-Subdivision:-
 Itissaidtoexistwhenthe
malocclusionexistsunilaterally.
Angle'sclassificationwasthefirst
comprehensive classificationof
malocclusion.ltisstillthemostwidely
acceptedclassificationandisusedroutinely
fordaytodaycommunicationbetween
clinicians.Withitssimplicity,italsohadits
inherentdrawbacks.

30. 1.Anglepresumedthefirstpermanentmolarsasfixed
pointswithinthejaws,whichdefinitelyisnotso
2.Angledependedexclusivelyonthefirstmolars.Hence,
theclassificationisnotpossibleifthefirstmolarsare
missingorifappliedinthedeciduousdentition
3.Malocclusionsareconsideredonlyinthe
anteroposteriorplane.Malocclusloninthetransverse
andverticalplanesarcnotconsidered
4.Individualtoothmalocclusionshavenotbeen
considered
5.Thereisnodifferentiationbetweenskeletalanddental
malocclusions
6.Etiologyofthemalocclusionshasnotbeenelaborated
upon

32. DEWEY'S MODIFICATION
OF ANGLE'S
CLASSIFICATION OF
MALOCCLUSION

33. Deweyin1915modifiedAngle'sClassIand
ClassIIIbysegregatingmalpositionsof
anteriorandposteriorsegmentsas:

34. Type1
AnglesClassIwithcrowdedmaxillaryanterior
teeth.

35. Type2
AnglesClassIwithmaxillaryincisorsinlabio-
version(proclined).

36. Type3
Angle'sClassIwithmaxillaryincisorteethin
linguoversiontomandibularincisorteeth
(anteriorsincrossbite).

37. Type4
Molarsand/orpremolarsareinbuccoor
linguo-version,butincisorsandcaninesarein
normalalignment(posteriorsincrossbite).

38. Type5
Molarsareinmesio-versionduetoearlylossof
teethmesialtothem(earlylossofdeciduous
molarsorsecondpremolar).
Dewey's Class I Type 5, permanent molar has drifted
mesially due to the early loss of the deciduous 2nd molar

39. Type1
Individualarcheswhenviewedindividuallyare
innormalalignment,butwheninocclusion
theanteriorsareinedgetoedgebite.
Dewey'sClassIIIType1.individualarcheswhenviewedindividuallyarein
normalalignment,butwheninocclusiontheanterlorsareinedgetoedge
bite

40. Type2
Themandibularincisorsarecrowdedand
lingualtothemaxillaryincisors.
Dewey's Class III Type 2, molars in Angle's Class III with mandibular
retroclined and/or crowded with maxillary anteriors in labio-version

41. Type3
Maxillaryarchisunderdeveloped,incrossbite
withmaxillaryincisorscrowdedandthe
mandibulararchiswelldevelopedandwell
aligned.
Dewey's Class III Type 3, maxillary arch is underdeveloped, in cross bite with maxillary
incisors crowded and the mandibular arch is well developed and well aligned

46. LISCHER'S MODIFICATION OF
THE
ANGLE'S CLASSIFICATION OF
MALOCCLUSION

47. Lischerin1933furthermodifiedAngle's
classificationbygivingsubstitutenamesfor
Angle'sClassI,IIandIIImalocclusions.Healso
proposedtermstodesignateindividualtooth
malocclusions.

48. NEUTRO-OCCLUSION
Neutro-occlusionisthetermsynonymousthe
Angle'sClassImalocclusion.
DISTO-OCCLUSION
Disto-occlusionissynonymouswithAngle's
ClassIImalocclusion.
MESIO·OCCLUSION
Mesio-occlusionissynonymouswithAngle's
ClassIIImalocclusion.

49. Lischersnomenclatureforindividualtooth
malpositionsinvolvedaddingthesuffix"version"to
awordtoindicatethedeviationfromthenormal
position.
1.Mesioversion-mesialtothenormalposition.
2.Distoversion-distaltothenormalposition.
Right mandibular 1st
molar is in mesioversion
The right lateral incisor and canine are in distoversion
(black arrow),and the right 1st premolar is rotated
mesio-buccally, i.e. in torsiversion

50. 3.Linguoversion-lingualtothenormalposition
4.Labioversion-labialtothenormalposition
Maxillary left 2nd premolar is
in linguocclusion
The maxillary canine and the mandibular
1st premolar are in bucca-occlusion

51. 5.Infraversion-inferiororawayfromthelineof
occlusion.
6.Supraversion-superiororextendedpastthelineof
occlusion.
Mesiopalatal or disto-buccal
rotation of the maxillary2nd
premolar
The mandibular 2nd molar shows an abnormal axial
inclination-axiversion (the dotted white line depicts the
present axial inclination whereas the black line the Ideal
axial inclination)

52. 7.Axiversion-theaxialinclinationiswrong;tipped.
The mandibular 2nd molar shows an abnormal axial inclination-axiversion (the
dotted white line depicts the present axial inclination whereas the black line the
Ideal axial inclination)

53. 8. Torsiversion-rotated on its long axis.
The right lateral incisor and canine are in
distoversion (black arrow),and the right 1st
premolar is rotated mesio-buccally, i.e. in
torsiversion
Mesiopalatal or disto-buccal rotation of the
maxillary2nd premolar

54. 9. Transversion-transposed or changes in the
sequence of position.
Transposition of the mandibular right canine with
the mandibular right lateral incisor

55. Primary classification
A-Cephalicanomalies:
1-Microcephalus:recedingchin
2-Macrocephalus:spacingoftheteeth
,mand.prognathism.
3-Osteogenic,neurogenic and tropic
disturbancesofthemaxillaand
mandible:e.g.leoniasisassea;hyperostosisofthemaxilla
,overgrowthofthemandible,retardationofthedentition,hemiatrophyof
theface.

56. B-Dysgnathicanomalies:
suggestedbyLischertodenotegross
developmentalabnormalitiesoftheteeth,
dentalarches,alveolarprocesses,jawsand
otheroralstructures.
Dysgnathicanomaliesincludethefollowing:
1-Macroglossa.
2-Facialclefts.
3-Totalorpartialagnathia.
4-Tumorsofthejaws&diseasesoftheperiodontium.
5-severechangesintheform,structure&relationshipof
theteethandjawswhichmaybeassociatedwith
systemic diseases;e.g.muscular
dystrophy,allergy,endocrine,nutritionaldisturbances….

57. C-Eugnathicanomalies:
SuggestedbyLischertodenote
anomaliesoftheteethalone.
Lischeraddthesuffix“version”toa
wordtoindicatethedeviationfrom
normalposition
Euganthicanomaliesincludethefollowing:
1-Disturbanceinthedegreeoftooth
development;impaction,retardation…
2-Positionofthetoothorteethinrelationtothe
lineofocclusionoranyofthethreepalnesof
space.

58. •Teethcanassumeanyoneorsomeof
thefollowingninepositions:
1-Linguoversion.
2-Labioversionorbuccoversion.
3-Mesioversion.
4-Distoversion.
5-Infraversion.
6-Supraversion.
7-Torsiversion;rotatedinitslongaxis.
8-Axioversion;wrongaxialinclination.
9-Transversion;wrongsequentialorder.

61. BENNETTE'S CLASSIFICATION OF
MALOCCLUSION

62. Bennetteclassifiedmalocclusionsbasedontheiretiologyas:
CLASSI
Abnormallocationofoneormoreteethisduetolocalfactors.
CLASSII
Abnormalformationofapartorawholeofeitherarchdueto
developmentaldefectsofbone.
CLASSIII
Abnormalrelationshipbetweentheupperandlowerarches
andbetweeneitherarchandthefacialcontour,dueto
developmentaIdefectsofbone.

63. Bennet’s Classification
•Accordingtoetiology:
ClassI:
abnormalpositionofoneormoreteethduetolocal
causes:
1-retaineddeciduousteeth.
2-teethofabnormalform.
3-superrnumeraries.
4-abnormalfrenumlabii.
5-abscentteeth.
6-ectopism.
7-impactionofupper1
st
molar.
8-thumborfingersucking.
9-prematurelossofpermanentordeciduousteeth

64. •Class II: abnormal formation of part or whole of either
arch due to developmantal Defects of bone:
1-conditions while deciduous molars in place:
a-rotation or lingaul placement of upper incisors.
b-inclination of lower incisors.
2-conditions after loss of deciduous molars:
a-labial or lingual inclination of canines.
b-buccal or lingual inclination of premolars.
c-accentuation of rotation of upper incisors or of inclinations of lower
incisors.

65. •ClassIII:abnormalrelationbetweenupper&lowerarches
andbetweeneitherarchandfacialcontourcorrelatedabnormal
formationofeitherarchduetodevelopmentaldefectofbone.
1-Vertical:openorcrossbite.
2-Anteroposterior(prenormalorpostnormalocclusions
orupperandlowerarches.
a-normalorsubnormal.
b-inferiorretrusion(inf.retrognathismorlinguoplacementor
linguoclination)
c-superiorprotrusion(sup.labiocliantionorlabioplacemant
sup.prognathism)
d-inferiorprotrusion(inf.prognathism)
e-superiorretrusion(sup.retrognathism)
f-doubleprotrusion.
g-doubleretrusion.
3-Lateral:buccalorlingualocclusionofupperandlowerteeth
ononesideorboth.

66. SIMON'S CLASSIFICATION OF
MALOCCLUSION

67. Simonin1930wasthefirsttorelatethedental
archestothefaceandcraniuminthethree
planesofspace,
i.e.
•Frankforthorizontal(vertically)
•Orbitalplane(anteroposteriorly)
•Rapheormediansagittalplane(transverse).

68. Frankforthorizontalplane(F-HPlane)ortheeye-ear
plane(E-EP)isdeterminedbydrawingastraightline
throughthemarginsofthebonyorbitdirectlyunder
thepupiloftheeyetotheuppermarginsofthe
externalauditorymeatus(thenotchabovethetragus
oftheear).Thisplaneisusedtoclassifymalocclusions
intheverticalplane.

69. Verticaldeviationswithrespect
totheplaneare:
1.AttractionsWhenthedental
archorpartofitisclosertothe
Frankforthorizontalplaneitis
referredtoasattraction.
2.AbstractionsWhenadental
archorapartofitisfurther
awayfromtheFrankfort
horizontalplane,itisreferred
toasabstraction.

70. Thisplaneisperpendiculartotheeye-earplane
(Frankforthorizontalplane)atthemarginofthebony
orbitdirectlyunderthepupiloftheeye.
Hereitispertinenttomentionthelawofthecanine.
AccordingtoSimoninnormalarmrelationship,the
orbitalplanepassesthroughthedistalaxialaspectof
themaxillarycanine.

71. Malocclusionsdescribedasanterior-posteriordeviationsbasedon
theirdistancefromtheorbitalplaneare:-
1.ProtractionTheteeth,oneorboth,dentalarches,and/orjawsare
toofarforward,i.e.placedforwardwheretheplanepasses
throughthedistalinclineofthecanine.
2.RetractionTheteethoneorbothdentalarchesand/orjawsaretoo
farbackward,Le.placedposteriortotheplanethannormal.

73. Therapheormediansagittalplaneisdeterminedby
pointsapproximately1.5cmapartonthemedian
rapheofthepalate.Theraphemedianplanepasses
throughthesetwopointsatrightanglestothe
Frankforthorizontalplane.

74. Malocclusionsclassifiedaccordingto
transversedeviationsfromthemedian
sagittalplaneare:
1.ContractionApartorallofthedental
archiscontractedtowardsthemedian
sagittalplane.
2.DistractionApartorallofthedental
archiswiderorplacedatadistance
whichismorethannormal.

75. Deviation of the dental arches in relation to
the orbital plane according to Simon, may
occurs as follows:
1-Both jaws are in normal relation to each other.
2-upper jaw normal, lower jaw distal.
3-upper jaw normal, lower jaw mesial.
4-lower jaw normal, upper jaw mesial.
5-lower jaw normal, upper jaw distal.
6-upper jaw mesial, lower jaw distal.
7-upper jaw distal, lower jaw mesial

76. SOAclassificationofmalocclusioninwhichtooth
malpositionsarerelatedtothreecraniofacial
planes:midsagittal,orbital,andFrankfort.Teeth
tooclosetothemidsagittalplanearein
contraction,whereasthosetoofarawayarein
distraction.Teethtooanteriortotheorbitalplane
areinprotraction,whereasthosetooposteriorto
theorbitalplaneareinretraction.Teethtooclose
totheFrankfortplaneareinattraction,whereas
those too distant are in
distraction.

77. SKELETAL CLASSIFICATION

78. Salzmannis1950wasthefirsttoclassifyon
occlusionbasedontheunderlyingskeletal
structures.

79. Thesemalocclusionswere
purelydentalwiththe
bonesofthefaceandjaws
beinginharmonywithone
anotherandwiththerest
ofthehead.Theprofileis
orthognathic.

80. TheskeletalClassIwasdividedfurtheraccordingthedental
malocclusionpresentas:
Division1
Localmal-relationsofincisors,canineandprernolars.
Division2
Maxillaryincisorprotrusion.
Skeletal Class I division 1; local mal relations of incisors, canine and premolars
Skeletal Class I division 2; maxillary incisor protrusion

81. Division3
Maxillaryincisorsinlinguoversion.
Division4
Bimaxillaryprotrusion.
Skeletal Class I division 3; maxillary anteriors in Iinguo-version
SkeletalClass I division4 rnaloccluslon,bimaxillaryprotrusion

82. Theseincludedmalocclusion
withasubnormaldistal
mandibulardevelopmentin
relationtothemaxilla.
TheskeletalClassIIwasfurther
dividedintotwodivisions
basedonthefeatures
commonlyseenwitha
mandibleplacedinretruded
position.

83. Division1
Themaxillarydentalarchis
narrowerwithcrowdinginthe
canineregion,crossbitemaybe
presentandtheverticalface
heightisdecreased.Themaxillary
anteriorteethareprotrudedand
theprofileisretrognathic.
Division2
Themaxillaryincisorsarelingually
inclined,thelateralincisorsmay
benormalorinlabio-version.

84. Herethereisanovergrowth
ofthemandiblewithan
obtusemandibularplane
angle.Theprofileis
prognathicatthe
mandible.

85. ACKERMAN-PROFITT
SYSTEM OF
CLASSIFICATION

86. AckermanandProfittproposedaverycomprehensivesystem
ofclassificationwhichdividedmalocclusionsinallthethree
planesofspaceandtendedtogiveanindicationtowardsthe
severityofthemalocclusionpresent.Thesystemproposed
byAckerman-Profittisbasedonthesettheory,whereaset
isdefinedonthebasisOfmorphologicdeviationsfromthe
ideal.

87. TheclassificationwasillustratedusingtheVennsymbolic
logicdiagram.Theclassificationconsideredninegroupsand
fivecharacteristics,andtheirinterrelationshipswereassessed.
Thefivecharacteristicsareasfollows:-
Venndiagram representing the 5 characters
CHARACTERISTIC 1-ALIGNMENT
CHARACTERISTIC 2-PROFILE
CHARACTERISTIC 3-TRANSVERSE RELATIONSHIPS
CHARACTERISTIC 4-CLASS
CHARACTERISTIC 5-OVERBITE

88. CHARACTERISTIC1-ALIGNMENT
Intraarchalignmentandsymmetryare
assessedaswhenseenintheocclusalview.A
dentalarchisclassifiedasideal!crowded/
spaced.

89. CHARACTERISTIC2-PROFILE
Theprofilecanbeconvex/straight/concave.
Thisalsoincludestheassessmentoffacial
divergence,i.e.anteriororposterior
divergence.

90. CHARACTERISTIC3-TRANSVERSERELATIONSHIPS
Theseincludethetransverseskeletalanddental
relationships.Buccalandpalatalcrossbitesare
noted.ThesearefurthersubclassifiedasunilateraI
orbilateral.Distinctionismadebetweenskeletal
anddentalcrossbites.

91. CHARACTERISTIC4-CLASS
Herethesagittalrelationshipoftheteethisassessed
usingtheAngleclassificationasClassI/ClassII/Class
III.Adistinctionismadebetweenskeletaland
dentalmalocclusions.

92. CHARACTERISTIC5-OVERBITE
Malocclusionsareassessedintheverticalplane.They
aredescribedasanterioropenbite/posterioropen
bite/anteriordeepbite/posteriorcollapsedbite.
Hereagainadistinctionismadeastowhetherthe
malocclusionisskeletalordental.

93. Thefirstcharacteristicisrepresentedasasquare
whichcontainsalargercirclerepresentingthe
profileorcharacteristic2.Thiscontainsthreesmaller
circlesoverlappingeachotherpartially,representing
thetransverse,sagittalandverticaldeviations
respectively.Theconfluenceofthesesetsformnine
groups,eachacombinationofcertain
characteristics.Theninthgrouprepresentsthemost
complexmalocclusionwithallpossiblefeatures.
The 9 groups formed usingt he Venn diagram model

96. GROUP 1:-Repersented as the outer envelop
or universe.since the degree of alignment &
symmetry are common to all dentitions.
GROUP 2:-the profile is affected by many
malocclusions so it becomes a major set with
in the universe.
GROUP 3-9:-Deviations in three planes of
space are represented by group 3-9 which
includes the overlapping or interlocking
subsets,all with in the profile.

97. Group 9:-would be more severe with
involvement of criteria from all groups.
ALIGNMENT : both arches crowed
PROFILE : posteriorly
divergent,convex
TYPE : maxillary palatal crossbite,
bilateral skeletal & dental
CLASS : class I,excessive overjet,
class II dental & skeletal
BITE DEPTH : open bite skeletal

98. INCISOR CLASSIFICATION

99. The incisor
classification is
consideredsimplerand
morerelevantthan
Angle'sclassification.It
wasadoptedbythe
British Standards'
Institutein1983,andis
based upon the
relationshipofthelower
incisoredgesandthe
cingulumplateauofthe
maxillary central
incisors.

100. CLASSI
Themandibularincisoredgesoccludewithorlie
immediatelybelowthecingulumplateauofthe
maxillarycentralincisors.

101. CLASSII
Themandibularincisoredgeslieposteriorto
thecingulumplateauofthemaxillary
centralincisors.
Division1
Themaxillarycentralincisorsareproclincdor
ofaverageinclinationandthereisan
increasedoverjet.
Division2
Themaxillarycentralincisorsareretro-
clined;theoverjetisnormallyminimum,
butmaybeincreased.

102. CLASSIII
Themandibularincisoredgeslieanteriortothe
cingulumplateauoftheuppercentralincisors;the
overjetisreducedorreversed.
NOTES:-
Alltherelevantclassificationshavebeendiscussed.
-TheAckermanandProfittclassificationconveysthemaximuminformation
regardingthecharacteristicsofamalocclusion,yetitisnotfrequentlyused.
-Theincisorclassificationisthesimplesttouse,yetnotthemostfrequently
used.
-Angle'sclassificationswithallitsshortcomings,isstillbyfarthemost
commonlyusedclassificationofmalocclusion.

103. Classification by Body-Build
Classificationofdentalarchesaccordingtobodytypeis
advocatedbyBerger,whousedKretschemer,somatic
typesasanadjunctinclassifyingarchforms.Accordingto
Kretschemer,thehumanbodymaybedivided
intothefollowingsomatictypes:
1-Leptosomaticorasthenic:-Longandslender.Atall,thin
personwithnarrowshoulders,slimarmsandhands,the
faceishighnarrow,themandibleisunder-developedand
thebridgeofthenoseover-developedinlength.

104. 2-Pyknic:-short and squat. A person who is
comparatively short, with a short neck and
compact trunk. The face is broad and less high
than the leptosomatic type.
3-Athletic Mascular type;-A person with strongly
developed muscles, broad shoulder, fully
developed chest. The mandible is square and fully
developed.
Note:these types do not always occur in their pure
state and one type may show features of any of
the others.

105. Etiologic Classification:
1-Osseous:
Thiscategoryincludesproblemsinabnormal
growth,size,shapeorproportionofanyofthe
bonesofthecraniofacialcomplex.Whenany
boneofthefacedevelopedinaperverted,
delayed,advancedorasynchronous,the
aberrationmaybereflectedinanorthodontic
problem.

106. Thetermbasalboneandapicalbaseused
todescribetheareasinvolvedinosseous
dyplasia.Theremainingbone,thealveolar
processreactslargelytotheneedsofdentition
itsupports,itcanbeeasilyshapedandaltered
bytoothmovements;thebasalboneisless
responsivetotheforcesoforthodontic
appliances.

107. 2-Muscular:Thisgroupincludesallproblemsin
malfunctionofthedentofacialmusculature,theroleof
musclesinetiologyofmalocclusionincludes:
a-Functional:“slideintoocclusion”duetoocclusal
interferance.
b-Determinal:suckinghabits(e.g.thumbandfinger
sucking,etc.)
c-Abnormalpatternofmandibularclosure.
d-Incompetantnormalreflexes(e.g.lipposture)
e-Abnormalmuscularcontractions(e.g.tongue
thrustingduringswallowing,mouthbreathing,etc.)

108. 3-Dentalproblems:Involveprimarilytheteeth
andtheirsupportingstructures.
Thiscategoryincludes:
a-Malpositionsofteeth.
b-Abnormalnumbersofteeth.
c-Abnormalsizeofteeth.
d-Abnormalconformationortextureofteeth.

109. LOGO