Etiology of Malocclusion: Causes and Classification

Etiology of
Malocclusion
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CONTENTS
1. Introduction.
2. Orthodontic Equation.
3. Primary Etiologic site.
4.CLASSIFICATION OF ETIOLOGICAL FACTORS :
I)- General Factors :-
1-Hereditary :-
a.Hereditary racial Influence
b.Hereditary facial type
c.Hereditary Influence on Growth and developed
d.Hereditary or specific dentofacial morphologiccharacteristics
2- Teratogenic effects of drugs.
3- Congenital defects
4- Environmental factors
5- Nutritional deficiency.
6- Systemic disease and Endocrinal disorders
7- Abnormal pressure habits
8- Trauma www.indiandentalacademy.comwww.indiandentalacademy.com

II) LOCAL FACTORS
1.Anomalies of tooth function.
2.Anomalies of number.
3.Anomalies of Tooth size and shape.
4.Abnormal labial frenum.
5.Premature loss of deciduous teeth.
6.Prolonged retention and abnormal
resorption of deciduous teeth.
7.Delayed eruption of permanent teeth
8.Abnormal eruptive path.
9.Ankylosis.
10.Local disease.
11.Improper dental restoration.www.indiandentalacademy.comwww.indiandentalacademy.com

.Etiology is the study of causes of dentofacial
abnormalities .
. It is the study or sum of knowledge regarding
the disease.
ETIOLOGY
In greek,
Aitia means cause and
Logous means study.

Moyer lists seven “causes and clinical entities”.Moyer lists seven “causes and clinical entities”.11
1 Heredity.1 Heredity.
2 Developmental defects of unknown origin.2 Developmental defects of unknown origin.
3 Trauma.3 Trauma.
4 Physical agents.4 Physical agents.
5 Habits.5 Habits.
6 Disease.6 Disease.
7 Malnutrition.7 Malnutrition.

Pre and Post natal factors of MalocclusionPre and Post natal factors of Malocclusion11
..
Shows the interdependence of etiological factors in MalocclusionShows the interdependence of etiological factors in Malocclusion
.Modification of SALZMANN’S diagrammatic representation.Modification of SALZMANN’S diagrammatic representation
of the etiologic factors in Malocclusion embodying pre and post natalof the etiologic factors in Malocclusion embodying pre and post natal
factors.1factors.1
• GENETICGENETIC
ENVIRONMENTALENVIRONMENTAL
• DEVELOPMENTALDEVELOPMENTAL

ORTHODONTIC EQUATION :-
(Dockrell R, 1952 ))
• It gives a brief expression of development of dentofacial abnormalities (malocclusion).It gives a brief expression of development of dentofacial abnormalities (malocclusion).
• CAUSE acts as TIMES on TISSUE produce RESULTSCAUSE acts as TIMES on TISSUE produce RESULTS
 POSTNATALPOSTNATAL
PRENATAL 1. MALFUNCTIONPRENATAL 1. MALFUNCTION
 (neuromuscular)(neuromuscular)
• FACTORSFACTORS
• 1. CONTINUOUS1. CONTINUOUS
2. MALOCCLUSION2. MALOCCLUSION
• OROR
(teeth)(teeth)
INTERMITTENTINTERMITTENT
GENERALGENERAL LOCALLOCAL
• 2. MAY ACT AS DIFFERENT2. MAY ACT AS DIFFERENT
3. OSSEOUS DYSPLASIA3. OSSEOUS DYSPLASIA
AGE LEVELAGE LEVEL
(craniofacial skeleton)(craniofacial skeleton)
(May be(May be single or in combination)single or in combination)

Primary Etiologic sites.Primary Etiologic sites.
• Neuromuscular systemNeuromuscular system ::
• It plays a primary role in the etiology ofIt plays a primary role in the etiology of
dentofacial deformity by the effects of reflexdentofacial deformity by the effects of reflex
contractions on the bony skeleton andcontractions on the bony skeleton and
dentition.dentition.
• Treatment of malocclusion must involveTreatment of malocclusion must involve
conditioning of reflexes to bring about moreconditioning of reflexes to bring about more
favorable functional environment for:-favorable functional environment for:-
Growing craniofacial skeleton .Growing craniofacial skeleton .
Developing dentition.Developing dentition.

• BoneBone :- Maxilla and mandible serve bases:- Maxilla and mandible serve bases
for dental arches. Aberrations in theirfor dental arches. Aberrations in their
morphology or growth may alter occlusalmorphology or growth may alter occlusal
relationship and functioning (orthodonticrelationship and functioning (orthodontic
treatment of skeleton disharmony maytreatment of skeleton disharmony may
either.either.
• Alter the growing craniofacial skeleton .Alter the growing craniofacial skeleton .
• Move teeth to mash its disharmony.Move teeth to mash its disharmony.

• Teeth-Teeth- The teeth may be a primary site in the etiologyThe teeth may be a primary site in the etiology
of dentofacial deformity.of dentofacial deformity.
• Gross variations in size, shape, number and position ofGross variations in size, shape, number and position of
teeth, all can produce malocclusionteeth, all can produce malocclusion
• Malpositions of teeth can induce malfunctions and thusMalpositions of teeth can induce malfunctions and thus
can alter the growth of the bones.can alter the growth of the bones.
• SOFT PARTSSOFT PARTS--The role of soft tissue is not asThe role of soft tissue is not as
clearly discernible nor it is as important as that of threeclearly discernible nor it is as important as that of three
sites stated above.sites stated above.
It can results form :It can results form :
• Periodontal disease-loss of its attachment apparatus.Periodontal disease-loss of its attachment apparatus.
• lesions including TMJ structures .lesions including TMJ structures .

General factorsGeneral factors
• General factors are those that effect theGeneral factors are those that effect the
body as a whole and have a profound effectbody as a whole and have a profound effect
on the greater part of the dentofacialon the greater part of the dentofacial
structure.structure.
HEREDITY FACTORSHEREDITY FACTORS:- heredity is:- heredity is
variously defined, more definitely as “Thevariously defined, more definitely as “The
appearance in the offspring of characters,appearance in the offspring of characters,
the factors for which are in the germ cells”.the factors for which are in the germ cells”.

• GALTON’S LAWGALTON’S LAW: Galton formulated the: Galton formulated the
statement that any organism of bisexualstatement that any organism of bisexual
parentage, derives one half its inherited qualitiesparentage, derives one half its inherited qualities
from its parents ( one quarter form each parents)from its parents ( one quarter form each parents)
one quarter form its grand parents one eight formone quarter form its grand parents one eight form
its great grand parents and so on.its great grand parents and so on.77
• These successive functions whose numeratorsThese successive functions whose numerators
are 1 and whose denominations are theare 1 and whose denominations are the
successive powers of 2 added together equal orsuccessive powers of 2 added together equal or
the total inheritance of the organisms.the total inheritance of the organisms.
½,1/4,1/8,1/16,1/32,1/64 =1½,1/4,1/8,1/16,1/32,1/64 =1
• The consensus of opinion seems to be thatThe consensus of opinion seems to be that
Galton’s law only expressed a part of what isGalton’s law only expressed a part of what is
known of the regular courses of inheritance .known of the regular courses of inheritance .

• According to KARKHAU’S ,heredity playsAccording to KARKHAU’S ,heredity plays
an important influence on the following:an important influence on the following:
1.1. size and shape of the teeth.size and shape of the teeth.
2.2. Time of eruption and change of dentitionTime of eruption and change of dentition
3.3. Abnormalities of individual teeth andAbnormalities of individual teeth and
groups of teethgroups of teeth
4.4. Size and shape of the maxilla andSize and shape of the maxilla and
mandible.mandible.77

TYPES OF HEREDITARY INFLUENCESTYPES OF HEREDITARY INFLUENCES22
::
A.A. HEREDITARY RACIAL INFLUENCE :-HEREDITARY RACIAL INFLUENCE :-
• In homogenous racial grouping, the incidence ofIn homogenous racial grouping, the incidence of
malocclusion seems relatively low .malocclusion seems relatively low .
• For eg, In certain areas of the world ,such as philliphieFor eg, In certain areas of the world ,such as philliphie
islands, malocclusion is almost non existent.islands, malocclusion is almost non existent.
• Professor Wood JonesProfessor Wood Jones :- Gave a statement that:- Gave a statement that
the more primitive race have larger and better teeththe more primitive race have larger and better teeth
rooted in roomy palates then member of civilized race.rooted in roomy palates then member of civilized race.
• Now Anthropologists show us that the jaws seem to beNow Anthropologists show us that the jaws seem to be
getting smaller, there is a greater frequency of impactiongetting smaller, there is a greater frequency of impaction
of third molar teeth, a greater incidence of congenitalof third molar teeth, a greater incidence of congenital
absence of certain teeth and a retrognathic tendency inabsence of certain teeth and a retrognathic tendency in
man as he ascends the evolutionary scale.man as he ascends the evolutionary scale.

B.HEREDITARY FACIAL TYPEB.HEREDITARY FACIAL TYPE11
:-:-
Facial type is heavily influenced by heredity .Facial type is heavily influenced by heredity .
• Facial typing is 3 dimensionalFacial typing is 3 dimensional
• Shape of head is different in different ethnic groups and mixtures ofShape of head is different in different ethnic groups and mixtures of
ethnic group.ethnic group.
• Three general type of shapes of headThree general type of shapes of head
• Brachycephalic – broad round headsBrachycephalic – broad round heads
• Dolichocephalic - long narrow headsDolichocephalic - long narrow heads
• Mesocephalic – a shape in between brachycephalic andMesocephalic – a shape in between brachycephalic and
dolichocephalicdolichocephalic
• In an arbitrary divisions there are many divisions gradients.In an arbitrary divisions there are many divisions gradients.
• A. Broad face- Broad cranialA. Broad face- Broad cranial
Broad facialBroad facial
Broad dental archesBroad dental arches
b. Long narrow face – harmonious bony structuresb. Long narrow face – harmonious bony structures
-Narrow dental arches-Narrow dental arches
c. Sex linked -By Hasund and Sivertsenc. Sex linked -By Hasund and Sivertsen
• He assume sex linked nature of facial width and dental arch shape.He assume sex linked nature of facial width and dental arch shape.
Specifically this means to the orthodontist that nature harmonizesSpecifically this means to the orthodontist that nature harmonizes
the dental structures according to the facial type.the dental structures according to the facial type.

HEREDITARY INFLUENCE ON GROWTH ANDHEREDITARY INFLUENCE ON GROWTH AND
DEVELOPMENT PATTERNDEVELOPMENT PATTERN :-:- recognizing that the ultimaterecognizing that the ultimate
morphogenetic pattern has a strong hereditarymorphogenetic pattern has a strong hereditary
component, it is reasonable to assume that thecomponent, it is reasonable to assume that the
accomplishment of that pattern is also at least partiallyaccomplishment of that pattern is also at least partially
under the influence of hereditary for eg, a child patient isunder the influence of hereditary for eg, a child patient is
very slow in losing his deciduous teeth and the eruption ofvery slow in losing his deciduous teeth and the eruption of
permanent teeth is equally slow. The mother will say “Hispermanent teeth is equally slow. The mother will say “His
brother and sisters are also very slow and so was I when Ibrother and sisters are also very slow and so was I when I
was his age.was his age.
• The environmental factors (Pre- natal and post natal playsThe environmental factors (Pre- natal and post natal plays
important role in the hereditary patternimportant role in the hereditary pattern
– The onset of puberty varies with the different races andThe onset of puberty varies with the different races and
with geographic distribution .with geographic distribution .
– Influence of sex is also another factor- growth andInfluence of sex is also another factor- growth and
development processes begins earlier is girls then indevelopment processes begins earlier is girls then in
boys.boys.
– Time of maturation is considerably more impredictableTime of maturation is considerably more impredictable
in the male sex.in the male sex.

HEREDITARY AND SPECIFICHEREDITARY AND SPECIFIC
DENTOFACIAL MORPHOLOGICDENTOFACIAL MORPHOLOGIC
CHARACTERISTICSCHARACTERISTICS 11
::
– Lundstrom made an intensive analysis of these characterstics inLundstrom made an intensive analysis of these characterstics in
twins.twins.
– Heredity could be considered significant in determing the followingHeredity could be considered significant in determing the following
characteristics.characteristics.
• Tooth size.Tooth size.
• Width and length of the archWidth and length of the arch
• Height of the palateHeight of the palate
• Crowding and spacing of teethCrowding and spacing of teeth
• Degree of sagittal overbite (overjet)Degree of sagittal overbite (overjet)
Hereditary also influence on-Hereditary also influence on-
– Position and conformation of perioral musculature to tongue sizePosition and conformation of perioral musculature to tongue size
and shape.and shape.
– Soft tissue peculiarities (character and texture of mucosa, frenumSoft tissue peculiarities (character and texture of mucosa, frenum
size, shape and positions etc)size, shape and positions etc)

TERATOGENIC EFFECTS OFTERATOGENIC EFFECTS OF
DRUGSDRUGS6,106,10
• Thalidomide – Phocomelia, multiple defects and growth.Thalidomide – Phocomelia, multiple defects and growth.
• Corticosteroids – cleft palate and lipCorticosteroids – cleft palate and lip
• Tetracycline –Discolored and deformed teeth,Tetracycline –Discolored and deformed teeth,
retarded bone growth.retarded bone growth.
• Phenytoin - Hypoplastic phalanges, cleft lip and palatePhenytoin - Hypoplastic phalanges, cleft lip and palate
• Warafin – Nose, eye and hand defects, growth retardation.Warafin – Nose, eye and hand defects, growth retardation.
• Asprin – cleft lip and palateAsprin – cleft lip and palate
• Aminopterin – anecephalyAminopterin – anecephaly
• Dilantin – cleft lip and palateDilantin – cleft lip and palate
• Ethyl alcohol – central and mid face deficiency,alcohol foetalEthyl alcohol – central and mid face deficiency,alcohol foetal
syndrome.syndrome.
• 5 – mercapturine – cleft palate5 – mercapturine – cleft palate
• Valium – cleft lip and palateValium – cleft lip and palate

• Diazepam – floppy baby syndrome.Diazepam – floppy baby syndrome.
• Anaesthetics –abortion and multiple defect.Anaesthetics –abortion and multiple defect.
(Chloroform,Halothane)(Chloroform,Halothane)
• Oral contraceptives – cardiac,ear and CNS defects.Oral contraceptives – cardiac,ear and CNS defects.
• Oral hypoglycaemis – neonatal hypoglycemia.Oral hypoglycaemis – neonatal hypoglycemia.
• Antithyroids – goitre with hypothyroidism.Antithyroids – goitre with hypothyroidism.
• ACE inhibitors – intrauterine growth retardation.ACE inhibitors – intrauterine growth retardation.
• Antihypertensives – anuria and multiple defects.Antihypertensives – anuria and multiple defects.
• Anti-tubercular(streptomycin) – gray baby syndrome.Anti-tubercular(streptomycin) – gray baby syndrome.
• Antiemetics – cleft palate and cardiovascular defects.Antiemetics – cleft palate and cardiovascular defects.
• Cigarette smoking – cleft lip and palate.Cigarette smoking – cleft lip and palate.
• Cytomegalovirus – microcephaly, hydrocephaly.Cytomegalovirus – microcephaly, hydrocephaly.
• X-radiation – microcephaly.X-radiation – microcephaly.
• Vitamin D excess – premature suture closure.Vitamin D excess – premature suture closure.

CONDITIONS IN THE EMBRYOCONDITIONS IN THE EMBRYO33
Faulty position in utero producing localizedFaulty position in utero producing localized
pressure and tissue development.pressure and tissue development.
• Cleft lip and cleft palate.Cleft lip and cleft palate.
• Injury during developmentInjury during development ..

CONGENITAL DEFECTSCONGENITAL DEFECTS1,2,41,2,4
:-:-
• These defects are usually assumed to have aThese defects are usually assumed to have a
strong genetic relationship.strong genetic relationship.
Following are some of the congenital conditionsFollowing are some of the congenital conditions
associated with dental malocclusions:associated with dental malocclusions:
• Abnormal state of mother during pregnancyAbnormal state of mother during pregnancy
• EndocrinopathiesEndocrinopathies
• Nutritional disturbancesNutritional disturbances
• Accidents during pregnancy and child birthAccidents during pregnancy and child birth
• Intra uterine pressureIntra uterine pressure
• Accidental traumatization of the fetus by externalAccidental traumatization of the fetus by external
forcesforces
• Macro and micro glossia.Macro and micro glossia.

CLEIDO CRANIAL DYSOSTOSISCLEIDO CRANIAL DYSOSTOSIS11
:-:-
• Maxillary retrusion and possible mandibularMaxillary retrusion and possible mandibular
protrusionprotrusion
• Over retained deciduous teeth and retardedOver retained deciduous teeth and retarded
eruption of permanent teetheruption of permanent teeth
• Presence of supernumerary teethPresence of supernumerary teeth
• Presence of short and thin rootsPresence of short and thin roots
CLEFT LIP AND CLEFT PALATECLEFT LIP AND CLEFT PALATE :-:-
• Patient may exhibit a number of dental problems,Patient may exhibit a number of dental problems,
including missing teeth, mobile teeth, rotations,including missing teeth, mobile teeth, rotations,
cross bite etc.cross bite etc.

MATERNAL RUBELLAMATERNAL RUBELLA
INFECTION:INFECTION:
• During pregnancy is believed to causeDuring pregnancy is believed to cause
widespread congenital malformation in thewidespread congenital malformation in the
child.child.
Features are: Dental hypoplasiaFeatures are: Dental hypoplasia
Retarded eruption of teethRetarded eruption of teeth
Extensive cariesExtensive caries
CEREBRAL PALSYCEREBRAL PALSY11
::
• Patient lacks muscular co-ordinationPatient lacks muscular co-ordination

Pierre robin syndromePierre robin syndrome44
:-:-
• Primary defect is arrestedPrimary defect is arrested
development ofdevelopment of
hypoplasia of mandiblehypoplasia of mandible
producing bird facesproducing bird faces
• Hypoplastic mandibleHypoplastic mandible
prevents the normalprevents the normal
descent of tonguedescent of tongue
between palatal shelvesbetween palatal shelves
causing cleft palatecausing cleft palate

TREACHER COLLINSTREACHER COLLINS
SYNDROMESYNDROME44
:-:-
• Hypoplasia of facialHypoplasia of facial
bones especiallybones especially
mandiblemandible
• Absence of palatineAbsence of palatine
bonesbones
• Cleft palateCleft palate
• High palateHigh palate
• Facial cleft and skeletalFacial cleft and skeletal
deformities gives bird likedeformities gives bird like
or fish like appearance.or fish like appearance.

TORTICOLLISTORTICOLLIS11
:-:- “Wry necks”“Wry necks”
• Sternocleidomastoid muscles can causeSternocleidomastoid muscles can cause
profound changes in the bony morphologyprofound changes in the bony morphology
of the cranium and face.of the cranium and face.
• Facial asymmetries with uncorrectableFacial asymmetries with uncorrectable
dental malocclusion may be created.dental malocclusion may be created.

CONGENITAL SYPHILISCONGENITAL SYPHILIS55
::--
• According to STEIN “some of hypoplasia of theAccording to STEIN “some of hypoplasia of the
teeth are certainly syphilitic, others may beteeth are certainly syphilitic, others may be
attributed to syphilis and other are certainly notattributed to syphilis and other are certainly not
caused by syphilis.caused by syphilis.
• Amorphism of the teeth,that is, teeth withoutAmorphism of the teeth,that is, teeth without
crown,somewhat resembling shark’s teeth,crown,somewhat resembling shark’s teeth,
twisted teeth, peg shaped teeth, uni or tri hornedtwisted teeth, peg shaped teeth, uni or tri horned
teeth, open bite and asymmetrical maxillae areteeth, open bite and asymmetrical maxillae are
also attributed to this cause.also attributed to this cause.

ENVIRONMENTAL FACTORSENVIRONMENTAL FACTORS11
:: Two types:Two types:
• Pre natal influencePre natal influence
• Post natal influencePost natal influence
• Prenatal influencePrenatal influence :- role of prenatal influence on:- role of prenatal influence on
malocclusion is probably very small .malocclusion is probably very small .
• But there are certain factors, in the presence of which can result inBut there are certain factors, in the presence of which can result in
abnormal growth of the orofacial region there by predisposing toabnormal growth of the orofacial region there by predisposing to
malocclusion.malocclusion.
Factors are :-Factors are :-
I Uterine postureI Uterine posture
II Fibroids of motherII Fibroids of mother
III Amniotic lesionsIII Amniotic lesions
Other possible causes can be :-Other possible causes can be :-
I Maternal diet and metabolismI Maternal diet and metabolism
II Drug induced deformities (Thalidomide, cleft lip and palate).II Drug induced deformities (Thalidomide, cleft lip and palate).
III TraumaIII Trauma
IV German measlesIV German measles
• Abnormal fetal posture and maternal fibroids, have caused markedAbnormal fetal posture and maternal fibroids, have caused marked
cranial or facial asymmetries that are apparent at birth but after firstcranial or facial asymmetries that are apparent at birth but after first
year of life most of them have disappeared. Thus deformity isyear of life most of them have disappeared. Thus deformity is
temporarytemporary

• Postnatal factors:Postnatal factors: Birth is a tremendous shock toBirth is a tremendous shock to
the newborn cranial bones slide and mold themselvesthe newborn cranial bones slide and mold themselves
more then the facial and dental areas.more then the facial and dental areas.
• The plasticity of structures is such that any injury wouldThe plasticity of structures is such that any injury would
be temporary except is race instancesbe temporary except is race instances
• Possible injury to the infant with forceps delivery casesPossible injury to the infant with forceps delivery cases
have been reported where TMJ got permanentlyhave been reported where TMJ got permanently
damaged during birth. Such patients show retardeddamaged during birth. Such patients show retarded
mandibular growth and this have a hypoplasticmandibular growth and this have a hypoplastic
mandible.mandible.
• Delivery induced deformation of upper jaw -:Delivery induced deformation of upper jaw -:
obstetricians frequently insert the fore finger and middleobstetricians frequently insert the fore finger and middle
finger into baby mouth to case passage through birthfinger into baby mouth to case passage through birth
canalcanal
• VOGELGESICHTVOGELGESICHT :- This is the inhibited growth of:- This is the inhibited growth of
mandible due to ankylosis of the tempero mandibularmandible due to ankylosis of the tempero mandibular
joint which may be due to development defects or due tojoint which may be due to development defects or due to
trauma at birth.trauma at birth.

CEREBRAL PALSYCEREBRAL PALSY11
• It is the lack of muscular co-ordination attributed to intracranial lesion.It is the lack of muscular co-ordination attributed to intracranial lesion.
It is commonly considered to be results of birth injury. There isIt is commonly considered to be results of birth injury. There is
typically malocclusion as the normal muscular balance is upset andtypically malocclusion as the normal muscular balance is upset and
the severity of malocclusion depends upon the extent of the lesions.the severity of malocclusion depends upon the extent of the lesions.
– Less frequent but more likely causes of malocclusion disablingLess frequent but more likely causes of malocclusion disabling
accidents that produce under pressure on the developingaccidents that produce under pressure on the developing
• Falls that cause condylar fracture may cause marked facialFalls that cause condylar fracture may cause marked facial
asymmetriesasymmetries
• Extensive scar tissue from burn may produce malocclusionExtensive scar tissue from burn may produce malocclusion
• Deformation of mandible byDeformation of mandible by
– Milwarkee braces in the treatment of scoliosisMilwarkee braces in the treatment of scoliosis
– Plaster neck cort in the case of feature of cervical vertebrae.Plaster neck cort in the case of feature of cervical vertebrae.
• In this case there is strong elevating force on the mandible thatIn this case there is strong elevating force on the mandible that
causes -:causes -:
– Maxillary incisors protrusionsMaxillary incisors protrusions
– Mandibular incisors fit into deep impression in the palatalMandibular incisors fit into deep impression in the palatal
mucosa .mucosa .

NUTRITIONAL DEFICIENCYNUTRITIONAL DEFICIENCY 33
::
• Nutritional deficiency during growth may result inNutritional deficiency during growth may result in
abnormal development causing malocclusion .abnormal development causing malocclusion .
• Nutritional related disorder such rickets, scurvy andNutritional related disorder such rickets, scurvy and
beriberi can produce severe malocclusion and may upsetberiberi can produce severe malocclusion and may upset
the dental development.the dental development.
• Malnutrition is more likely to affect the quality of tissueMalnutrition is more likely to affect the quality of tissue
being formed thus the size of parts .being formed thus the size of parts .
Vitamin AVitamin A :- has a profound effect upon the:- has a profound effect upon the
development and subsequent health of epithelial tissuedevelopment and subsequent health of epithelial tissue
and tissue derived from the primitive ectoderm. Absenceand tissue derived from the primitive ectoderm. Absence
of this vitamin during the period when dental structures areof this vitamin during the period when dental structures are
being formed results in disturbance of the calcification ofbeing formed results in disturbance of the calcification of
the enamel and dentin, retards tooth eruption and isthe enamel and dentin, retards tooth eruption and is
deleterious to the growth and development of dentaldeleterious to the growth and development of dental
structures .structures .

• Vitamin BVitamin B:-:- deficiency in these vitamin affects the nervesdeficiency in these vitamin affects the nerves
producingproducing severe irritation of there structure and resultingsevere irritation of there structure and resulting
in ain a polyneuritis known as beriberi. Growth is retarded inpolyneuritis known as beriberi. Growth is retarded in
the child and atrophy of the digestive tractthe child and atrophy of the digestive tract occur . Thereoccur . There
is retardation of growth in the dentofacial tissues.is retardation of growth in the dentofacial tissues.
• Vitamin CVitamin C :- Scurvy results form such a deficiency:- Scurvy results form such a deficiency
connective tissues, including bone, cartilage and dentinconnective tissues, including bone, cartilage and dentin
are greatly affected in the formation stage.are greatly affected in the formation stage.
Vitamin DVitamin D :- Bone growth and the quality of osseous:- Bone growth and the quality of osseous
structure is very dependent upon this vitamins. Deficiencystructure is very dependent upon this vitamins. Deficiency
produces rickets in childrenproduces rickets in children
-Enamel and dentin are poorly formed and eruption of-Enamel and dentin are poorly formed and eruption of
teeth is delayedteeth is delayed
- Jaw growth is retarded and the alveolar processes are- Jaw growth is retarded and the alveolar processes are
bulky and poorly calcified (mineral content of bone isbulky and poorly calcified (mineral content of bone is
reducedreduced about 50%)about 50%)

• SYSTEMIC DISEASE ANDSYSTEMIC DISEASE AND
ENDOCRAINAL DISODERSENDOCRAINAL DISODERS 1,31,3
:-:-
Role of thyroid gland:Role of thyroid gland:
HYPOTHYROIDISM :-HYPOTHYROIDISM :-
• Retardation in rate of calcium deposition in bones and teeth.Retardation in rate of calcium deposition in bones and teeth.
• Marked delay in tooth bud formation and eruption of teeth.Marked delay in tooth bud formation and eruption of teeth.
• Deciduous teeth are often over retained and the permanent teethDeciduous teeth are often over retained and the permanent teeth
are slow to eruptare slow to erupt
• Abnormal root resorption (By Dr Herman Beck’s investigationAbnormal root resorption (By Dr Herman Beck’s investigation
• Irregularities in tooth arrangement and crowding of teeth can occurIrregularities in tooth arrangement and crowding of teeth can occur
• Myxedema also results from hypothyroidism (failure in Naso orbitalMyxedema also results from hypothyroidism (failure in Naso orbital
development )development )
HYPERTHYRODISM:-HYPERTHYRODISM:-
• Retardation of skeletal growth due the lack of minerals for boneRetardation of skeletal growth due the lack of minerals for bone
growthgrowth
• Early closure of the ephiphyseal growth centre occurs sometimesEarly closure of the ephiphyseal growth centre occurs sometimes
resulting in dwarfismresulting in dwarfism
• Premature eruption of deciduous teethPremature eruption of deciduous teeth
• Disturbed root resorption of permanent teethDisturbed root resorption of permanent teeth
• Early eruption of permanent teethEarly eruption of permanent teeth

ROLE OF PARATHYROID GLANDS:-ROLE OF PARATHYROID GLANDS:-
• Parathyroid gland regulates the level of blood calcium andParathyroid gland regulates the level of blood calcium and
phosphorous metabolism. They play an important role in thephosphorous metabolism. They play an important role in the
calcification of the teeth and bone.calcification of the teeth and bone.
HYPOPARATHYROIDISM:-HYPOPARATHYROIDISM:-
• Dentin shows hypo calcificationDentin shows hypo calcification
• Produces increase in blood calciumProduces increase in blood calcium
• Skeleton growth is impairedSkeleton growth is impaired
HYPERPARATHYROIDISM:-HYPERPARATHYROIDISM:-
• Fibrous changes of the bone narrow due to abnormalFibrous changes of the bone narrow due to abnormal
increase in the osteoclasts resulting in conditions known asincrease in the osteoclasts resulting in conditions known as
osteitis fibrosa.osteitis fibrosa.
• Teeth may become mobile due to loss of cortical bone andTeeth may become mobile due to loss of cortical bone and
resorption of the alveolar processresorption of the alveolar process

ROLE OF PITUTARY GLAND:-ROLE OF PITUTARY GLAND:-
• it controls the body growth and developmentit controls the body growth and development
HYPOPITUTARISM :-HYPOPITUTARISM :-
• It leads to dwarfismIt leads to dwarfism
• Retardation of tooth eruptionRetardation of tooth eruption
• Reduction in growth of paranasal sinus especially the frontalReduction in growth of paranasal sinus especially the frontal
• Reduction in arch length resulting in crowdingReduction in arch length resulting in crowding
• Size of maxilla and mandible are reduced both anteriorly andSize of maxilla and mandible are reduced both anteriorly and
verticallyvertically
HYPERPITUTARISM:-HYPERPITUTARISM:-
• It leads to gigantism in early life and acromegaly in adult lifeIt leads to gigantism in early life and acromegaly in adult life
• Acceleration of tooth eruptionAcceleration of tooth eruption
• Paranasal sinuses are overdevelopedParanasal sinuses are overdeveloped
• Enlargement of tongue i.e. macroglossiaEnlargement of tongue i.e. macroglossia
• There is over growth of alveolar process in height and width,There is over growth of alveolar process in height and width,
resulting in spacing of teeth.resulting in spacing of teeth.

ABNORMAL PRESSUREABNORMAL PRESSURE
HABITSHABITS
• Severity of malocclusion caused due to abnormal habitSeverity of malocclusion caused due to abnormal habit
depends upon the trident of factor ie. Frequency,depends upon the trident of factor ie. Frequency,
intensity, and duration. The role of abnormal pressureintensity, and duration. The role of abnormal pressure
habit in the cause of malocclusion will be dealt with behabit in the cause of malocclusion will be dealt with be
following heads.following heads.
• Abnormal suckingAbnormal sucking
• Abnormal swallowingAbnormal swallowing
• Tongue thrustingTongue thrusting
• Mouth breathingMouth breathing
• Lip bitingLip biting
• BruxismBruxism

TRAUMATRAUMA 11
::
Both prenatal trauma to the fetus and postnatal injuriesBoth prenatal trauma to the fetus and postnatal injuries
results in dentofacial deformityresults in dentofacial deformity
• prenatal trauma and birth injuryprenatal trauma and birth injury
• Postnatal – as a child learns to crawl and walk face andPostnatal – as a child learns to crawl and walk face and
dental process receive many blows that are not recordeddental process receive many blows that are not recorded
in history .in history .
• Such undiscovered traumatic experience many explainSuch undiscovered traumatic experience many explain
so called idiopathic eruptive abnormalities .so called idiopathic eruptive abnormalities .
• non vital deciduous teeth have abnormal resorptionnon vital deciduous teeth have abnormal resorption
patterns and may defect the permanent successors.patterns and may defect the permanent successors.
• If blow to the dental areas is strong, it may causesIf blow to the dental areas is strong, it may causes
fracture of jaws and tooth (as in automobile accidents).fracture of jaws and tooth (as in automobile accidents).

POSTUREPOSTURE 11
::
• Poor postured condition can cause malocclusionPoor postured condition can cause malocclusion
• A child with the head hung so that the chin rests on the chest,A child with the head hung so that the chin rests on the chest,
has been accused of creating mandibular retrussion.has been accused of creating mandibular retrussion.
• Full fledged dental malocclusion may be caused by a childFull fledged dental malocclusion may be caused by a child
resting his head for period of time each day or sleeping on hisresting his head for period of time each day or sleeping on his
arm or fistarm or fist
• Also poor posture may accentuateAlso poor posture may accentuate on existing malocclusionon existing malocclusion

LOCAL FACTORSLOCAL FACTORS
Anomalies of FormationAnomalies of Formation55
::
• Hypoplasia of the enamel – is the result ofHypoplasia of the enamel – is the result of
deficiencies in the form of the organic enameldeficiencies in the form of the organic enamel
matrix. It is a disturbance of the ameloblastsmatrix. It is a disturbance of the ameloblasts
• Hutchinson’s teethHutchinson’s teeth:- Presence in congenital:- Presence in congenital
syphilis. Permanent central incisors and the firstsyphilis. Permanent central incisors and the first
molar show characteristic Hutchinson’s markingsmolar show characteristic Hutchinson’s markings
• Mottled enamel:Mottled enamel: It is defect of calcification whichIt is defect of calcification which
show itself as a chalky, white, brown or blackshow itself as a chalky, white, brown or black
discoloration of the enamel in severe cases thediscoloration of the enamel in severe cases the
teeth are pitted.teeth are pitted.

Anomalies of NumberAnomalies of Number 1 -1 -
SupernumerarySupernumerary
-Missing-Missing
• Supernumerary teethSupernumerary teeth:- No definite time for them to:- No definite time for them to
develop.May appear prior to birth or as late as 10 to 12develop.May appear prior to birth or as late as 10 to 12
yrsyrs
• occur most commonly in maxillaoccur most commonly in maxilla
• Frequently seen supernumerary tooth is mesiodensFrequently seen supernumerary tooth is mesiodens
occurs singly near the midline, palatal to maxillary centraloccurs singly near the midline, palatal to maxillary central
incisors and is conical in shape.incisors and is conical in shape.
• Of major concern to the dentist is frequently of deflectionOf major concern to the dentist is frequently of deflection
or non eruption of maxillary centre incisors as a results ofor non eruption of maxillary centre incisors as a results of
(Mesiodens) supernumerary teeth .(Mesiodens) supernumerary teeth .
– In any patient who shows a marked differences in times ofIn any patient who shows a marked differences in times of
eruption of right and left central incisors supernumerary should beeruption of right and left central incisors supernumerary should be
suspected and investigated radio graphically.suspected and investigated radio graphically.

Missing teethMissing teeth :- a. congenital:- a. congenital
b. traumab. trauma
• These are more frequent than supernumeraryThese are more frequent than supernumerary
most commonly missing teeth (in decreasingmost commonly missing teeth (in decreasing
order)order)
• Maxillary and mandibular 3rd molarsMaxillary and mandibular 3rd molars
• Maxillary lateral incisorsMaxillary lateral incisors
• Congenital absence problems are more likely toCongenital absence problems are more likely to
be bilateral than are supernumerary teeth.be bilateral than are supernumerary teeth.
• Congenital absence in more frequent inCongenital absence in more frequent in
permanent dentition than in deciduouspermanent dentition than in deciduous

• When permanent teeth are missing the roots ofWhen permanent teeth are missing the roots of
their deciduous predecessor may not resorb e.g.their deciduous predecessor may not resorb e.g.
when maxillary lateral incisor are missingwhen maxillary lateral incisor are missing
maxillary canine may erupt mesial to maxillarymaxillary canine may erupt mesial to maxillary
canine into the space of missing teeth.canine into the space of missing teeth.
• Teeth may be lost as a result of trauma. If theTeeth may be lost as a result of trauma. If the
lost anterior tooth is deciduous, spacelost anterior tooth is deciduous, space
maintenance is usually unnecessary unless themaintenance is usually unnecessary unless the
spaces serves as the inciting factor for tonguespaces serves as the inciting factor for tongue
thrust habit.thrust habit.
• When the permanent central or lateral incisor isWhen the permanent central or lateral incisor is
lost, space maintenance is required if these islost, space maintenance is required if these is
even the slightest crowding tendency contiguouseven the slightest crowding tendency contiguous
teeth will drift into edentulous areateeth will drift into edentulous area

Anomalies of tooth size and shapeAnomalies of tooth size and shape ::
Size of teeth is largely determined by hereditySize of teeth is largely determined by heredity
• There is great variation both from individual to individualThere is great variation both from individual to individual
and even within the same individual related to size andand even within the same individual related to size and
shape.shape.
• Occasionally developmental abnormalities occur withOccasionally developmental abnormalities occur with
one or more teeth being anomalous in shape or fusedone or more teeth being anomalous in shape or fused
with a neighbouring tooth. The significant increasedwith a neighbouring tooth. The significant increased
arch length can not be tolerated and malocclusionsarch length can not be tolerated and malocclusions
results.results.
• Anomalies of size are relatively frequent inAnomalies of size are relatively frequent in
mandibular premolar area. Mandibular second premolarmandibular premolar area. Mandibular second premolar
shows great variation or in shape and size. It may haveshows great variation or in shape and size. It may have
a extra lingual cusp with usually serves to increase thea extra lingual cusp with usually serves to increase the
mesiodistal dimensions.mesiodistal dimensions.

• Related to tooth shape-Related to tooth shape- most frequentmost frequent
departure from normal is “peg lateral”departure from normal is “peg lateral”
because of its diminutive size, excessivebecause of its diminutive size, excessive
spacing will often occur in the maxillaryspacing will often occur in the maxillary
anterior segment.anterior segment.
• Anomalies of shape can occur as a result ofAnomalies of shape can occur as a result of
development defects such as :development defects such as :
• Amelogenesis imperfectaAmelogenesis imperfecta
• GeminationGemination
• Dens in denteDens in dente
• FusionFusion

ABNORNAL LABIAL FRENUMABNORNAL LABIAL FRENUM11
::
• At birth the labial frenum is attached to the alveolar ridgeAt birth the labial frenum is attached to the alveolar ridge
with fibers running into the lingual interdental papilla. Aswith fibers running into the lingual interdental papilla. As
the teeth erupt and alveolar bone is deposited, the frenalthe teeth erupt and alveolar bone is deposited, the frenal
attachment migrates superiorly with respect to alveolarattachment migrates superiorly with respect to alveolar
ridge. Fibers may persist between maxillary centralridge. Fibers may persist between maxillary central
incisors in the V shaped intermaxillary suture.incisors in the V shaped intermaxillary suture.
• FAUSTIN WEBER STATED that before considering theFAUSTIN WEBER STATED that before considering the
abnormal labial frenum as the causative factor forabnormal labial frenum as the causative factor for
malocclusion all the following condition should bemalocclusion all the following condition should be
eliminated.eliminated.
– Microdontia and Macrognathia.Microdontia and Macrognathia.
– Supernumerary (especially mesiodens)Supernumerary (especially mesiodens)
– Peg lateral missing later incisors.Peg lateral missing later incisors.
– Heavy occlusion against the lingual surfaces of max incisorsHeavy occlusion against the lingual surfaces of max incisors
– Habits such as thumb sucking tongue thrusting lip biting or lipHabits such as thumb sucking tongue thrusting lip biting or lip
suckingsucking
– Midline cyst.Midline cyst.
• factor in persistent diastemas.factor in persistent diastemas.

• TAYLOR confirmed that inter incisor spacing classes in most of theTAYLOR confirmed that inter incisor spacing classes in most of the
cases without any interferencecases without any interference
According to him.According to him.
• AgeAge Incidence of DiastemaIncidence of Diastema
• 6 years6 years 97%97%
• 6-7 years6-7 years 88%88%
• 10-11 years10-11 years 48%48%
• 12-18 years12-18 years 7%7%
• Existence of a heavy fibrous frenum does not always mean thatExistence of a heavy fibrous frenum does not always mean that
spacing is present. One diagnostic test that helps to determine thespacing is present. One diagnostic test that helps to determine the
role of frenum is – Blanche test.role of frenum is – Blanche test.
• Normally Frenum migrates superiorly sufficiently by 10-12 yrs of ageNormally Frenum migrates superiorly sufficiently by 10-12 yrs of age
so that on stretching upper lip there is no demonstrable change at theso that on stretching upper lip there is no demonstrable change at the
maxillary central interdental papilla.maxillary central interdental papilla.
• Where there is a heavy fibrous frenum which may be contributoryWhere there is a heavy fibrous frenum which may be contributory
however blanching of the tissue just lingual to maxillary centralhowever blanching of the tissue just lingual to maxillary central
incisors can be noted (it means that fibrous attachment still remainsincisors can be noted (it means that fibrous attachment still remains
in the area)in the area)
• The difficulty lies in establishing whether this fibrous attachment isThe difficulty lies in establishing whether this fibrous attachment is
causative or resultant.causative or resultant.
• Hereditary component is a majorHereditary component is a major

Premature loss of deciduous teeth:Premature loss of deciduous teeth:
Deciduous teeth serve asDeciduous teeth serve as
• organ of masticationorgan of mastication
• ““space savers” for permanent teethspace savers” for permanent teeth
• assist in maintaining the opposing teeth atassist in maintaining the opposing teeth at
proper occlusal level.proper occlusal level.
• So premature loss of deciduous teethSo premature loss of deciduous teeth
(posteriors) means that probably malocclusion(posteriors) means that probably malocclusion
will result unless space maintainers are placed.will result unless space maintainers are placed.
• Mandibular deciduous canine and molarsMandibular deciduous canine and molars
combined width is 1.7mm greater on each sidecombined width is 1.7mm greater on each side
than combined width of mandibular permanentthan combined width of mandibular permanent
canine and premolars.canine and premolars.

PROLONGED RETENTION ANDPROLONGED RETENTION AND
ABNORMAL RESORPTION OFABNORMAL RESORPTION OF
DECIDUOUS TEETH:-DECIDUOUS TEETH:-
• Mechanical interference due to prolonged retention ofMechanical interference due to prolonged retention of
deciduous teeth can deflect an erupting permanent toothdeciduous teeth can deflect an erupting permanent tooth
into a position of malocclusion.into a position of malocclusion.
• Also if the roots of the deciduous teeth are not resorbedAlso if the roots of the deciduous teeth are not resorbed
properly, uniformly or in time permanent successors mayproperly, uniformly or in time permanent successors may
be either held from eruption or they may be deflected inbe either held from eruption or they may be deflected in
malpositions.malpositions.
• One basic rule to follow is that dentist should maintainOne basic rule to follow is that dentist should maintain
the tooth shedding time table at about the same level forthe tooth shedding time table at about the same level for
each of the four buccal segments.each of the four buccal segments.
If canine & premolars are clinically present in one orIf canine & premolars are clinically present in one or
more segment while the deciduous counterparts are stillmore segment while the deciduous counterparts are still
firmly anchored in one or more of remaining segments,firmly anchored in one or more of remaining segments,
an immediate radiographic examination is essential toan immediate radiographic examination is essential to
see whethersee whether

• Permanent successors are there or notPermanent successors are there or not
• Or if some obstruction is there like if one root or part ofOr if some obstruction is there like if one root or part of
the root does not resorb along with rest of the rootsthe root does not resorb along with rest of the roots
• When the dental developmental age either abnormalWhen the dental developmental age either abnormal
advanced or retarded, a check into endocrine historyadvanced or retarded, a check into endocrine history
should be made e.g. hypothyroidism – prolongedshould be made e.g. hypothyroidism – prolonged
retention of deciduous teeth.retention of deciduous teeth.
• Precocious gonadotropic hormonal development- dentalPrecocious gonadotropic hormonal development- dental
devlopment patterns is markedly accelerated.devlopment patterns is markedly accelerated.
• Even when the deciduous teeth appear to be lost on time,Even when the deciduous teeth appear to be lost on time,
the patient should be observed radio graphically until thethe patient should be observed radio graphically until the
permanent teeth erupt. Therefore Frequently fragmentspermanent teeth erupt. Therefore Frequently fragments
of deciduous roots are retained in the alveolar processes.of deciduous roots are retained in the alveolar processes.
There fragments if not resorbed, may deflect theThere fragments if not resorbed, may deflect the
permanent tooth’s eruptive path.permanent tooth’s eruptive path.
• Also there fragments can serve as focus for cystAlso there fragments can serve as focus for cyst
formation.formation.

DELAYED ERUPTED OF PERMANENTDELAYED ERUPTED OF PERMANENT
TEETHTEETH
• In addition to the possibility of an endocrine disorderIn addition to the possibility of an endocrine disorder
( hypothyroidism )other possibilities can be:( hypothyroidism )other possibilities can be:
• congenital absence of toothcongenital absence of tooth
• supernumerary tooth or deciduous root mechanismsupernumerary tooth or deciduous root mechanism
interferenceinterference
• Mucosal barriersMucosal barriers
• Frequently early loss of deciduous tooth means earlyFrequently early loss of deciduous tooth means early
eruption of permanent tooth but occasionally a bony crypteruption of permanent tooth but occasionally a bony crypt
forms in the line of eruption of permanent tooth and it willforms in the line of eruption of permanent tooth and it will
erupt.erupt.
• So careful radiographic examination is necessarySo careful radiographic examination is necessary

ABNORMAL ERUPTIVEABNORMAL ERUPTIVE
PATH:PATH:
• It is usually a secondary manifestation of a primaryIt is usually a secondary manifestation of a primary
disturbance with a hereditary pattern of serve crowding anddisturbance with a hereditary pattern of serve crowding and
totally inadequate space to accommodate all the teeth,totally inadequate space to accommodate all the teeth,
deflection of erupting tooth may be merely an adaptivedeflection of erupting tooth may be merely an adaptive
response to the conditions present.response to the conditions present.
• It may also be because of presence of supernumerary tooth.It may also be because of presence of supernumerary tooth.
• Retained deciduous tooth or root fragment bony crypt barrier :Retained deciduous tooth or root fragment bony crypt barrier :
• There physical barriers influence the direction ofThere physical barriers influence the direction of
eruption and set up in an abnormal path.eruption and set up in an abnormal path.
• Sometimes there is no space problem or noSometimes there is no space problem or no
physical barrier and even then teeth are eruptingphysical barrier and even then teeth are erupting
in abnormal direction.in abnormal direction.

• A blow or trauma can be the cause someA blow or trauma can be the cause some
abnormal eruptive paths are of idiopathic origin.abnormal eruptive paths are of idiopathic origin.
• One form of abnormal eruption is referred toOne form of abnormal eruption is referred to
ECTOPIC ERUPTION in its most common formECTOPIC ERUPTION in its most common form
a permanent tooth erupting.a permanent tooth erupting.
• Though alveolar Process causes resorption on aThough alveolar Process causes resorption on a
conlogeous deciduous tooth or permanent toothconlogeous deciduous tooth or permanent tooth
rather than its predecessor.rather than its predecessor.
• Frequently maxillary permanent first molar is theFrequently maxillary permanent first molar is the
offending tooth causing abnormal resorption ofoffending tooth causing abnormal resorption of
maxillary deciduous second molar, as it eruptsmaxillary deciduous second molar, as it erupts
between the distal convexity of this tooth i.e.between the distal convexity of this tooth i.e.
maxillary deciduous second molar. Ectopicmaxillary deciduous second molar. Ectopic
eruption may generally be considered as aeruption may generally be considered as a
manifestation of arch length deficiency.manifestation of arch length deficiency.

ANKYLOSIS:ANKYLOSIS:
• Ankylosis is encountered relatively frequently during the 6Ankylosis is encountered relatively frequently during the 6
to 12 years age period.to 12 years age period.
• It is probably due to injury of some sort as a result ofIt is probably due to injury of some sort as a result of
which a part of the period membrane is perforated and awhich a part of the period membrane is perforated and a
bony bridge forms joining the lamina dura and cementum.bony bridge forms joining the lamina dura and cementum.
This bridge need not to be very large to stop the normalThis bridge need not to be very large to stop the normal
eruptive force of a tooth. It may occur on buccal or lingualeruptive force of a tooth. It may occur on buccal or lingual
aspects and thus may be totally unrecognizable in aaspects and thus may be totally unrecognizable in a
dental radiograph.dental radiograph.
• Clinically: dentist sees what appears to be a submergingClinically: dentist sees what appears to be a submerging
of the offending tooth.of the offending tooth.
• Actually the other teeth are erupting and the ankylosedActually the other teeth are erupting and the ankylosed
tooth is nottooth is not

LOCAL DISEASESLOCAL DISEASES
• GINGIVAL AND PERIODONTAL :-GINGIVAL AND PERIODONTAL :-
• Infections and disorders of periodontal membrane and gingival haveInfections and disorders of periodontal membrane and gingival have
a direct and highly localized effect on teeth. They may causea direct and highly localized effect on teeth. They may cause
• loosening of teeth (mobility)loosening of teeth (mobility)
• Loss of teethLoss of teeth
• Change in closure pattern of mandible to avoid trauma to sensitive areas.Change in closure pattern of mandible to avoid trauma to sensitive areas.
• DENTAL CARIES :-DENTAL CARIES :-
Its can causeIts can cause
• loss of arch length due to series of proximal carious lesions that areloss of arch length due to series of proximal carious lesions that are
unrepairedunrepaired
• If there occurs extensive caries:- May lead to premature loss of tooth, so itIf there occurs extensive caries:- May lead to premature loss of tooth, so it
may lead to subsequentmay lead to subsequent
• Drifting of contiguous teeth.Drifting of contiguous teeth.
• Abnormal axial inclinationAbnormal axial inclination
• Over eruption etcOver eruption etc

IMPROPER DENTAL RESTORATIONSIMPROPER DENTAL RESTORATIONS
• If over extended proximal restoration isIf over extended proximal restoration is
given then there may occur an increase ingiven then there may occur an increase in
arch length which may lead to :arch length which may lead to :
• Break in the continuity of arch (BrokenBreak in the continuity of arch (Broken
contacts)contacts)
• Functional prematuritiesFunctional prematurities
• Severe strain on canine- lateral contactSevere strain on canine- lateral contact
• Rotations in anterior segment.Rotations in anterior segment.

• Maxillary deciduous canine and molars width isMaxillary deciduous canine and molars width is
more than maxillary permanent canine andmore than maxillary permanent canine and
premolars (0.9mm on each side) leeway spacepremolars (0.9mm on each side) leeway space
• This space differential is necessary to allow forThis space differential is necessary to allow for
the occlusal adjustment and settling in of thethe occlusal adjustment and settling in of the
occlusal as the terminal plane relationship isocclusal as the terminal plane relationship is
corrected.corrected.
• Premature extraction of deciduous second molarPremature extraction of deciduous second molar
will lead to mesial drifting of permanent firstwill lead to mesial drifting of permanent first
molar and it will block permanent second premolar and it will block permanent second pre
molar even if permanent second pre molarmolar even if permanent second pre molar
erupts it will be deflected buccally or lingually intoerupts it will be deflected buccally or lingually into
a position of malocclusiona position of malocclusion

ReferencesReferences
1.1. T.M.GRABER:ORTHODONTICS PRINCIPAL AND PRACTICE, EDITIONT.M.GRABER:ORTHODONTICS PRINCIPAL AND PRACTICE, EDITION
33rdrd
:135-285:135-285
2.2. BRASH,McKEAG,SCOTT:THE ATIOLOGY AND MALOCCLUSION OFBRASH,McKEAG,SCOTT:THE ATIOLOGY AND MALOCCLUSION OF
THE TEETH,SECOND EDITION,1956 DENTAL BOARD OF THE U.KTHE TEETH,SECOND EDITION,1956 DENTAL BOARD OF THE U.K
3.3. STRANG,THOMPSON:A TEXTBOOK OF ORTHODONTIA,FOURTHSTRANG,THOMPSON:A TEXTBOOK OF ORTHODONTIA,FOURTH
EDITION.LEA AND FEBIGER,1958:184,221,227.EDITION.LEA AND FEBIGER,1958:184,221,227.
4.4. NEVILLE,DAMM,ALLEN,BOUQOT:ORAL AND MAXILLOFACIALNEVILLE,DAMM,ALLEN,BOUQOT:ORAL AND MAXILLOFACIAL
PATHOLOGY.EDITION 2PATHOLOGY.EDITION 2ndnd
, SAUNDERS 2005: 4,42-43., SAUNDERS 2005: 4,42-43.
5.5. SHAFER,HINE,LEVY:TEXTBOOK OF ORAL PATHOLOGY,FIFTHSHAFER,HINE,LEVY:TEXTBOOK OF ORAL PATHOLOGY,FIFTH
EDITION.ELSEVIER.2005.453-454,52-55.EDITION.ELSEVIER.2005.453-454,52-55.
6.6. W R.PROFFIT, CONTEMPORARY ORTHODONTICS; 3W R.PROFFIT, CONTEMPORARY ORTHODONTICS; 3rdrd
EDITION ,EDITION ,
MOSBY, 2000 113 TO 144.MOSBY, 2000 113 TO 144.
7.7. Klein: Pressure habits, etiological factors in maloccclusion – AJO-DO:Klein: Pressure habits, etiological factors in maloccclusion – AJO-DO:
1952: 8: 569 - 5871952: 8: 569 - 587
8.8. Lundström : The significance of early loss of deciduous teeth in the etiologyLundström : The significance of early loss of deciduous teeth in the etiology
of malocclusion AJO-DO , 1955: 11 :819 - 826of malocclusion AJO-DO , 1955: 11 :819 - 826
9.9. R.S.SATOSKAR,BHANDARKAR,AINAPURE:PHARMACOLOGY ANDR.S.SATOSKAR,BHANDARKAR,AINAPURE:PHARMACOLOGY AND
PHARMACOTHERAPEUTICS, SEVENTEENTH EDITION, MUMBAIPHARMACOTHERAPEUTICS, SEVENTEENTH EDITION, MUMBAI
POPULAR PRAKASHAN, 2001, 1077.POPULAR PRAKASHAN, 2001, 1077.

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