William James defined habits as new pathways formed in the brain causing certain stimuli to discharge in particular ways. Habits can be useful, like proper tongue posture, or harmful, like thumb sucking. Thumb sucking can lead to malocclusion if it persists past age 4 by exerting pressure on teeth and arches. Tongue thrusting involves placing the tongue between incisors and can develop as an adaptation to displaced teeth. It may worsen malocclusion over time. Mouth breathing due to nasal obstruction can also affect jaw and tooth development, resulting in narrow arches and open bites. Management of harmful habits involves reminders, appliances, and exercises to encourage new behaviors.

1. Definitions::
William James:An acquired habit,from psychological pointofview, is nothing but a new pathway of discharge
formed in the brain, by which certain incoming currents ever after tend to escape.Moyers: Habits are learned pattern
of muscle contraction,which are complexin nature.Finn: A habitis an act, which is sociallyunacceptable.Definitions
:
According to William James: Useful habits: These habits include the habits of
normal function such as correct tongue posture, proper respiration etc.
Harmful habits: These are the ones which exert stresses against the teeth and
dental arches such as mouth breathing, lip sucking, thumb sucking. :
According to William James: Useful habits:These habits include the habits ofnormal function such as
correct tongue posture,proper respiration etc.Harmful habits:These are the ones which exert stresses againstthe
teeth and dental arches such as mouth breathing,lip sucking,thumb sucking.Classification ofhabits
According to Finn and Sim: Compulsive habits :When the habithas acquired a fixation in the child to the
extent that he retreats to the practice of this habit whenever his securityis threatened.This is his safetyvalve when
emotional pressures become too much to cope with. Non-compulsive habits :Habits which are easily dropped or
added from the child behaviour pattern as he matures.
Various habits are: Thumb sucking/finger sucking Tongue thrusting Mouth breathing Lip biting and lip
sucking Postural habits Nail biting Masochistic habits Bobbypin opening Frenum thrusting Bruxism Cheek
biting/sucking
Gellin: Defines digit sucking as placement of thumbor one or more fingers in various depths into mouth. Moyers:
Repeated and forceful sucking of thumb with associatedstrong buccal and lipcontractions. :
Gellin:Defines digitsucking as placementofthumb or one or more fingers in various depths into mouth.Moyers:
Repeated and forceful sucking of thumb with associated strong buccal and lip contractions.Thumb sucking/finger
sucking
Psychology of thumb sucking:
Psychology of thumb sucking Freudian theory: He suggests thatorality in the infants is related to pregenital
organization and thus,the objectof thumb sucking is nursing.He believes thatabrupt interference in such basic
mechanism will likelylead to substitution ofsuch antisocial tendencysuch as stuttering.Oral drive theory (Sears and

2. Wise):He suggests thatthe strength of oral drive is in part a function of how long a child continuous to feed by
sucking.Thus it is not the frustration of weaning but,rather oral drive which has been strengthened bythe
prolongation ofnursing.
Benjamins theory : He proposed two theories- Thumb sucking is an expression ofa need to suck that arises
because ofassociation ofsucking with primaryreinforcing aspects offeeding.Thumb sucking arises from the rooting
and placing reflexes common to all mammalian infants.A multidisciplinaryresearch team atthe university of Alberta
supportthe theory that digital sucking habits in humans are simple learned response.
Clinical aspects of digital sucking::
Clinical aspects ofdigital sucking:Prenatal/antenatal :Shortly before the child passes through the birth canal, the
fetus shows increased muscular activity and the thumb mayfind its way into the mouth,thus initiating thumb sucking
habitbefore birth. The fetus seeks a ‘position ofcomfort’ which occasionallyinterferes with postnatal dentofacial
development.
Postnatal: A : Finger sucking from birth to 4 yrs of age: Infants generallystart sucking habitin the first three
months oflife, which may be due to feeding problems,emotional stress with which they are unable to cope, insecurity
and desire to attract attention. For the 1 st4yrs of life damage to occlusion is confined largelyto the anterior segment.
The damage is temporary,provided the child starts with normal occlusion.An exerciser or pacifier was developed
which is hoped to greatly reduce the need and desire ofthe infant for thumb sucking between meals and atbed time.
e.g Nuk sauger nipple.Edwall functional nursing nipple.Nuk sauger nipple Conventional nipple
B Active finger sucking after 4 yrs of age : The permanence ofmalocclusion increases ifthe habit persists beyond 4
yrs of life. Tridentof habitfactors: DURATION FREQUENCY INTENSITY Duration:duration of sucking i.e hours pe r
day of sucking,plays a major role in tooth displacement.Frequency:frequency of habit during day and nightaffects
the end result.Intensity: more the intensityof sucking more the perioral muscles function and more is the damage.
Effect of thumb sucking:
Effect of thumb sucking The of effect of sucking habitdepends on:Position ofthumb in mouth Leverage effect the
child gains againstthe other teeth and the alveolus.Apposition of sucking finger on the maxilla:In case the finger
rests on the lower incisors as a fulcrum Promotes the developmentofclass I, class IIdiv I malocclusion.Anterior
open bite. Protraction of maxillary anterior teeth. Labial tipping ofmandibular anterior teeth.
In case the finger rests on the lower anteriors then lingual displacementoflower anteriors will occur.Vertical
equilibrium is altered on the posterior teeth leading to more eruption ofposterior teeth causing open bite.Arch form is
affected due to alteration in balance between cheek and tongue pressures i.e m axillaryarch tends to become v-
shaped.Thumb sucking is associated with tongue thrustto maintain the anterior seal.
Narrower nasal floor and high palatal vault Maxillary lip hypotonic and mandibular lip hyperactive Hyperactive
mentalis muscle In case the child bites on both its index fingers,it leads to protrusion and open bite corresponding
with the side in which the finger is being held
Bilateral posterior crossbite as the posterior teeth are forced palatallyby the buccal musculature.Apposition offinger
sucking on the mandible:In case the fingers are pressed on the lingual side ofthe mandibular alveolar process and
lower anterior teeth- labial tipping of upper and lower incisors is due to forward and downward displacementof
tongue.
Can lead to class III malocclusion in which mandible jaw is pulled forward byfingers Facial asymmetrymay be
caused Line ofocclusion is changed Callus formation and low virus infection on fingers which is continuouslybeen
sucked.

3. Management:
ManagementMost of the children discontinue their habitatthe age of 4yrs or by 5 yrs No treatmentis recommended
as the malocclusion,ifpresent,corrects itselfas the habitceases Adultapproach:As the time of eruption of the
permanentincisors approach,a straightforward discussion with a dentistis recommended Reminder therapy:a
simple method is to secure an adhesive bandage with waterprooftape on the finger that is being sucked.
If this fails then elastic bandage looselywrapped around the elbow prevents the arm from flexing and finger from
being sucked.If this fails then the reminder appliance is fitted to actively impede finger sucking.eg ,crib, maxillary
lingual arch with crib etc. Reward system:if the reminder therapyfails then reward system is used in which small
tangible reward dailyfor not engaging in the habit.
Psychological approach : Dunlop theory (beta hypothesis)-This theorystates thatby practicing a bad habitwith the
intent to stop it, one learns notto perform the undesirable act.The child will not derive any satisfaction from
purposeful repetition ofthe habitbut will experience a painful reaction in its performance and will graduallyabandon
the habit. This is applicable to older children whose cooperation can be obtained.Chemical approach :In this a hot
flavored, bitter tasting or foul smelling preparations can be applied on the finger that is being sucked.e.g red pepper,
quinine,asafetide.
Appliances used :
Appliances used Removable appliances :Tongue spikes Tongue crib Rake appliance Vestibular screen Fixed
appliances Hayrake Maxillary lingual arch with palatal crib
A crib is a habitretraining appliance which utilizes a bluntwire ‘reminder’ which prevents the child from indulging into
the habit. It serves the following functions:To break the suction and force on anterior segment.As a reminder.Make
the habitnon pleasurable.Forces the tongue backward,changing the shape during restposition from an elongated
mass to a more wider position,nearlylike a normal tongue.
A rake may be removable or fixed. It discourages notonly thumb sucking buttongue thrusting and abnormal
swallowing also.Another appliance by Haskell and Mink called the blue grass appliance was used to stop thumb
sucking.In this a modified sixsided roller machine from teflon was used.
Time of therapy:
Time of therapy Check up appointments are made at3-4 wk interval. Appliance to be worn for 4-6 months.A period
of 3 months oftotal absence of finger sucking is good insurance for relapse.The appliance is removed in parts i.e
after 3 months ofhabit free interval the spurs are cut off,3 wks later posterior loop extension is cutand 3 wks later
palatal bar and crown may be removed.
Tongue thrusting:
Tongue thrusting Definition:
P lacementoftongue tip forward between incisors during swallowing.Tongue thrusting maybe primarycause of
malocclusion or itmay be secondaryadaptive factor as in case in skeletal open bite.It is generallyassociated with
long term thumb sucking children.
Classifications of tongue thrust: :
Endogenous Habitual Adaptive (enlarged tonsils,pharyngitis) Anterior lateral,complexPrimarySecondary
Acc to Graber There are considerable amountofevidences that indicate that tongue thrustis the retention of
the infantile suckling mechanism.Whatever may be the cause of tongue habit(size, posture,function) it serve s as the
effective cause of malocclusion.Acc to Proffit Whenever there is an open bite due to tongue sucking habita
compensatorymuscle activity of the tongue develops which accentuates the deformity.Bringing the lips together and

4. placing the tongue between anteriors is successful maneuver to make an anterior seal.After the sucking stops,the
anterior open bite tends to close spontaneouslyotherwise an anterior seal bytongue tip remains necessary.
In modern view point : Tongue thrustswallow is seen in two circumstances,in younger children in normal
occlusion in whom itrepresents a transitional stage in normal physiologic maturation and in individuals ofany age in
displaced anteriors.Therefore tongue thrustswallow should be considered the result ofdisplaced incisors and notthe
cause.Acc to equilibrium theory:The pressure generated is very less to effect the equilibrium butif there is forward
resting posture oftongue the duration of pressure ,even if very light could effect tooth movement.
Effects of tongue thrusting:
Effects of tongue thrusting Increase in overjet and overbite. Tongue no longer lie on the lingual cusps ofthe buccal
segmentand posterior teeth erupt; thus eliminating interocclusal clearence.May lead to bruxism. Narrowing of
maxillary arch as the tongue drops lower in the mouth.Clinicallythis maybe seen as unilateral cross bite.In
horizontal growth pattern, tongue dysfunction leads to bimaxillaryprotusion.In vertical growth pattern, tongue
dysfunction leads to lingual inclination oflower incisors.Diastemas maybe present.Deep bite in lateral tongue thrust.
Careful differentiation mustbe done among simple,complextongue thrustand retained infantile swallowing pattern
and faulty tongue posture.Prognosis is good for simple tongue thrust.Notvery good for complex tongue thrust.Poor
for retained infantile swallowing pattern.Protracted tongue posture can be: Endogenous - no certain treatment
Acquired- can be corrected Normal tongue Tongue thrust
Method of examination tongue dysfunction:
Method of examination tongue dysfunction Electronic recording.Electromyographic examination.Recording of
pressure exerted by tongue intra orally. Roentgenocephalometric analysis.Cine-radiographic.Paltographic.
Neurophysiologic examination.
Management :
Management Simple tongue thrust: it is the tongue thrustwith teeth together swallow.If there is
excessive labioversion ofmaxillaryincisors,treatmentoftongue thrustshould be done after retraction of incisors.
Patient should be taughtswallowing exercises with sugar less mintand should be instructed to practice 40 times a
day and maintain the record. On second appointment,patientshould be able to swallow correctlyat will. Sugar less
drops maybe used to reinforce the unconscious swallow.If the problem continues,soldered lingual arch wire having
shortand sharp spurs can be inserted.
To summarize;Conscious learning ofnew reflex. Transferal of control of the new swallow Pattern to the
subconscious level.Reinforcementofthe new reflex.
Complex tongue thrust : It is the tongue thrustwith teeth apartswallow.Malocclusion presentare:Poor
occlusal fit. Generalized anterior open bite. Open bite may not be presentif the tongue is seated evenly atop of all
teeth. Treatment: Treat occlusion first.When the treatmentis in retentive phase- muscle training is begun.Maxillary
lingual arch appliance is necessaryfor these patients.There may be chances ofrelapse and prognosis is notvery
good
Retained infantile swallow : It is defined as the undue persistence ofthe infantile swallow well pastthe
normal time for its departure.These patients occlude onlyon one molar in each segment.These patients do nothave
expressive faces.They have difficulty in breathing.Low gag threshold It is a problem ofneuromuscular development.
Appliance used is tongue crib with 3-4 v-shaped projections which extend downward up to the cinguli of lower
incisors when the casts are occluded.Prognosis is poor.
Abnormal tongue posture : Endogenous tongue posture:itis an inherentlyabnormal tongue posture
and the tip of the tongue persists in lying between incisors.There is stabilityof incisor relationship e ven though a mild
open bite is seen.Prognosis poor.Acquired tongue posture:it is due to chronic pharyngitis,tonsillitis,nasorespiratory

5. disturbance.Refer the patient to otolaryngologistfor the precipitating factors.Followed by lingual arch wire with sharp
spurs.This is correctable after the precipitating factors are corrected. Adaptive tongue posture:This is due to narrow
maxilla.When rapid palatal expansion is completed and posterior intercuspation is correctnormal posture returns.
Mouth breathing:
Mouth breathing Respiratoryneeds are the primarydeterminantofthe posture of jaws and tongue.Therefore it is
reasonable thatan altered respiratorypattern, such as breathing through mouth rather than nose,could alter the
equilibrium ofpressure on jaws and teeth and affect both jaws growth and tooth position.Finn classified mouth
breathing into 3 different categories:OBSTRUCTIVE HABITUAL ANATOMIC
Obstructive mouth breathing : These are the children who have complete obstruction ofnormal air
flow of air through the nasal passages.Due to difficulty in breathing through nose child is forced to breath through
mouth.Habitual mouth breathing :This is a child who continuouslybreath through mouth by force of habit, even if
abnormal obstruction is removed.Anatomic mouth breathing :They are the one whose shortupper lip does not
permitcomplete closure withoutundue effect.
Factors considered for mouth breathing:
Factors considered for mouth breathing For an average individual,when ventilation exchange rate of 40-45l/min.is
reached,there is a transition to partial oral breathing.Heavy mental concentration could lead to increase air flow and
a transition to partial mouth breathing.If nose is partiallyobstructed,or there is a tortuous pass age an individual shifts
to mouth breathing.Swelling ofnasal mucosa accompanying common cold converts one into mouth breathing.
Chronic respiratoryobstruction produced due to inflammation within the nasorespiratorysystem can lead to mouth
breathing Pharyngeal tonsils and adenoids can cause mouth breathing.
Clinical features:
Clinical features Associated with impeded maxillarygrowth.Narrow jaw with high palate, dental crowding as well as
retrognathism ofmaxilla.Prognathism ofmandible. Tongue lies flaton th floor of mouth so it does not play its role in
developmentofmaxilla.Hyperactivity of facial muscles especiallybuccinator,impedes the developmentofmaxilla.In
class II malocclusion there is increase in overjet.Bilateral cross bite.Hyperplasia ofgingiva. Extra oral appearance of
these patients is often conspicuous and is termed ‘adenoid facies’.
There is downward and backward rotation of mandible to maintain postural changes leading to open bite anteriorly.
Two different tongue posture are possible:type I -in class III malocclusion tongue is flatand protruding.type II- in
class II malocclusion tongue has a flat and retracted position.Examination ofbreathing mode:Cotton pledgettest:A
cotton butterfly is placed below the nostrils and observed.The nasal breather will displace the cotton pledgeton
expiration where as the mouth breather will not. Mirror test: mirror is held in front of both the nostrils,in nasal breather
the mirror will cloud with condensed moisture during expiration.Observation ofnostrils:Alar muscles are inactive in
mouth breathers i.e do not change their size on inhalation or expiration where as nasal breathers do.
Management :
ManagementIf mouth breathing is due to nasal obstruction,then operation by an E.N.T surgeon is indicated i.e in
case of allergic rhinopathy.If patient has habitual mouth breathing then pre-orthodontic therapyshould be carried out
by: breathing exercises,incorporation oforal or vestibular screen.In case in which vestibular screen is used holes
can be slowlyclosed as the patient starts breathing through nose.Myofunctional exercises like to hold a piece of card
board to improve lip seal.
Bruxism :
Bruxism Definition : it is the habitual grinding ofteeth, during sleep.this term is applied to clenching of teeth and also
to repeated tapping of teeth. Incidence:5- 20 % Etiology (Nadler and Meklas): Local Systemic Psychological
occupational ;

6. Local : These factors are associated when there is mild form ofocclusal discomfortduring transition from
deciduous to permanentdentition.Systemic: - gastrointestinal disturbances. - sub clinical nutritional deficiencies. -
allergy or endocrine disturbances. - hereditary background.Psychological factors :they are believed to be most
common causes ofbruxism.emotional tension such as fear,rage,rejection.Occupations:athletes engaged in
physical activities often develop bruxism.in which work has been more precise such as watch makers.voluntary
bruxism in those who have habit of chewing gum,
Tobacco or objects such as pencil or tooth picks.Clinical features (Glaros and Rao) : divided into six categories -
Effect on dentition:severe wearing or attrition of teeth- both occlusal and interproximal.Effect on periodontium:loss
of integrity of periodontal structures,resulting in loosening,drifting ofteeth, gingival recession with bone loss.Effect
on masticatorymuscles:hypertrophy of masticatorymuscles,particularlymasseter muscle,cause trismus and alter
opening and closing movements ofjaw.TMJ disturbance maybe seen.Head pain and facial pain.Psychological and
behavior effects.
Management :
ManagementIf the underlying cause of the bruxism is an emotional one,the nervous factor mustbe corrected if the
disease is to be cured.Removable rubber splints can be worn at nightto immobilize the jaws.A vinyl plastic bite
guard that covers the occlusal surfaces ofall teeth plus 2mm ofthe buccal and lingual surfaces can be worn at night
to prevent abrasion.
Lip sucking and lip biting :
Lip sucking and lip biting Lip sucking is a compensatoryactivity which results from an excessive overjet and relative
difficulty of closing the lips during deglutation.In mostcases itis the mandibular lip thatis involved in sucking,
although biting habits ofmaxillary lip is also seen.The deformity reaches maximum when the discrepancybetween
the maxillary incisors and mandibular incisors becomes equal to the thickness ofthe lip.(B.J.Johnson).
Common features : Labioversion ofmaxillaryteeth and lingual displacementofmandibular teeth.Vermillion
border is hypertrophic and redundantduring rest.Flaccid lip due to lengthening.Chronic herpes with areas of
irritation and cracking of lips.If a patient has lip sucking habitduring sleep then telltale Redness and irritation
extending from mucosa to skin of lower lip is seen.If patientis class II div1 malocclusion then the lip suking habitis
only adaptive.
Management : If the patient is having class IIdiv 1 malocclusion then the treatmentshould be done
orthodontically.The lip sucking habitgenerallyceases after the treatment.If the habitcontinues then,the lip
appliance i.e lip plumper is given.The appliance can be modified by adding acrylic between base wire and auxillary
wire. Removal of appliance is done in parts i.e first the auxillary wire then the base wire is removed. A period of 8 -9
months is required to cease the habitcompletely.
Postural habits :
Postural habits Poor postural position mayalso lead to malocclusion.A stoop shoulder child,with head hung so that,
a chin rests on the chest, has been accused ofcreating his own mandibular retrusion.Child and adults do notlie in
one position during sleep,they keep on changing which are induced by nervous reflexes. Before the sleeping position
can produce any deleterious effecton jaw growth, the child would have to be suffering from some osteogenic
deficiency.
Posture during the child’s waking hours is more importantthen position during sleep in the production of dental
malocclusion.Deformity,flattening of the skull and facial asymmetrymay occasionallydevelop during firstyear in
infant who habituallylie in the supine position with head turned to right or left. Poor posture may accentuate an
existing malocclusion,butthis remains to be proved or disapproved conclusively.

7. Nail biting :
Nail biting This habitis often mention as a cause ofof tooth malpositions.High strung,nervous children most often
displaythis habit.Nail biting is absentunder 3yrs of age. There is rapid increase from 6yrs of age up to 12 yrs in girls
and 14 yrs in boys, followed by rapid decline after the age of 16 yrs. It is more commonlyseen in adolescence in boys
than among girls.
Clinical features :may induce crowding rotations ofincisors attrition ofincisal edges these malocclusions are due to
the untoward pressures introduced during nail biting.Management:It is importantto study child’s physical,mental
and social difficulties ifthe roots of the habit are to removed.If the child continues after suggestions he maybe in
need of psychiatric consultation.
He may be associated with toe nail biting.Kanner and Bakwin found toe nail biting only in girls.Arousing a new
interestsuch as nail polish has been found helpful in girls and boys maybe given reward for sparing his nails.
Punishments,scolding and restraints are ofno value. Lightcotton wittens may be worn at night to act as a reminder.
Nightsuits which encase the feet may be worn at night. Rewards are sometimes ofvalue.
Masochistic habits:
Masochistic habits In this habita child uses his finger nails to strip the gingival tissues from the labial surface ofthe
lower cuspid.sometimes a child completelydenudes the tooth of marginal gingiva and unattached gingival tissues,
exposing the alveolar bone.Management: Psychiatric assistance.Taping the finger.
Bobby-pin opening:
Bobby-pin opening This is opening bobbypins with anterior incisors to place them in hair. Mostly seen in teen aged
girls.Clinical features:Notched incisors Teeth partiallydenuded oflabial enamel maybe observed.Management:
Calling attention to the harmful resultis generallyall that is necessaryto stop the habit.
Frenum thrusting:
Frenum thrusting If a child has spaced incisors ,the child may lock his labial frenum between these teeth and permit
it to remain in this position for several hours.This habitis rarely seen.This develop into tooth displacing habitby
keeping the central incisors apart.Management:Orthodontic correction ofincisors.
Cheek sucking/biting:
Cheek sucking/biting This habitmaypersistas a substitute for thumb sucking or tongue thrusting.Effects:May lead
to posterior open bite.Wet like horizontal swelling maybe formed as a resultof constantirritation. Management:
Removable lateral crib may be used.Vestibular screen or oral screen maybe used.