Malocclusions Questions And Answers

Malocclusions Definitions

1. Habits: It is a frequent or constant practice or acquired tendency, which has been fixed by frequent repetition

2. Preventive orthodontics: It is defined as the action taken to preserve the integrity of what appears to be normal occlusion at a specific time

3. Serial extraction: It is defined as the correctly timed, planned removal of certain deciduous and permanent teeth in mixed dentition stages.

4. Space maintainers: Space maintainers can be defined as appliances used to maintain space or regain minor amounts of space lost, so as to guide the unerupted tooth into a proper position in the arch.

5. Myofunctional appliances: Defined as loose fitting/passive appliances which harness natural forces of orofacial musculature, that are trans¬mitted to teeth and alveolar bone.

6. Space regainers: Appliances used to regain the space lost due to early loss of primary teeth are called space regainers.

Malocclusions Long Essays

Question 1. Define and classify space maintainers. Write in detail about the lingual arch space maintainer.
Answer:

Space maintainers Definition: Space maintainers can be defined as appliances used to maintain space or regain minor amounts of space lost, so as to guide the unerupted tooth into a proper position in the arch.

Space maintainers Classification:

• Removal Space Maintainers
  • Cast partial and wrought partial
  • Active or passive
  • Functional or non-functional
• Fixed Space Maintainers
  • Bonded or Banded
  • Active or Passive
  • Functional or non-functional

Lingual Arch Space Maintainer

It is a fixed, non-functional, passive mandibular arch appliance

Lingual Arch Space Maintainer Fabrication:

• Stainless steel wire is adapted over the lingual surfaces of teeth
• Bands are anchored over the first permanent molar
• The wire is soldered to the band

Lingual Arch Space Maintainer Indications:

• Bilateral loss of posterior teeth
• Minor movement of the anterior teeth
• Maintenance of leeway space
• Space regaining

Lingual Arch Space Maintainer Contraindications: Before the eruption of the mandibular incisors

Lingual Arch Space Maintainer Disadvantages:

• Loss of cementation and solder
• May cause untoward movement

Lingual Arch Space Maintainer Variations:

• Looped lingual archwire
• Lingual horizontal tube
• Ellis loop lingual archwire
• Lingual arch with canine spur

Question 2. Define space maintainers and space management. Write in detail about the eruption guidance appliances.
Answer:

• Space Maintainers and space management Definition: Space maintainers, can be defined as appliances used to maintain space or regain minor amounts of space lost, so as to guide the unerupted tooth into a proper position in the arch.
• Space management is defined as the process of maintaining a space in a given arch previously occupied by a tooth or a group of teeth

Eruption Guidance Appliance/ Distal Shoe appliance: Introduced by Willet

Eruption Guidance Appliance Indications:

• Premature loss of second primary molar
• Bilateral space loss

Eruption Guidance Appliance Contraindications:

• Inadequate abutments
• Poor patient control

Read And Learn More: Pedodontics Short Essays Question And Answers

• Congenital missing first molar
• Systemic diseases

Eruption Guidance Appliance Classification:

• Fixed:
  • Functional
  • Non-functional
• Removable:
  • Fabrication
  • Depends on the distance between the distal surface of the primary molar to the mesial surface of the permanent molar
  • The crown is fabricated over the permanent molar
  • It has a mesial gingival extension
  • This extension should be constructed to extend 1 mm below the marginal ridge
  • Such an extension guide the eruption of underlying permanent teeth.

Question 3. Define serial extraction. Write about indication, contra-indications, and various methods of it.
Answer: It is defined as the correctly timed, planned removal of certain deciduous and permanent teeth in mixed dentition stages.

Serial extraction Indications:

• Class 1 with anterior crowding
• Lingually placed lateral incisors
• Severe anterior proclamation
• Unilateral loss of canine
• Abnormal resorption of deciduous
• Absence of primate spaces
• Ankylosis
• Ectopic eruption

Serial extraction Contraindications:

• Mild to moderate crowding
• Congenital absence of teeth
• Extensive caries
• Deep bite or Open bite
• Severe class 2, 3
• Cleft lip and palate

Serial extraction Method:

1. Dewel’s method (CD4):

2. Tweed’s method (D4C):

Serial extraction Advantages:

• Minimizes the use of mechanotherapy
• Reduces complexity of treatment

Question 4. Define and classify oral habits. Discuss thumb-sucking habits, their effects on the oro-facial complex, and its management.
Answer:

Definition: It is a frequent or constant practice or acquired tendency, which has been fixed by frequent repetition

Oral Habits Classification:

• Obsessive:
  • Intentional
  • Masochistic
• Non-Obsessive:
  • Unintentional
  • Functional
• Useful Habits and Harmful Habits:
• Pressure habits and Biting habits
• Empty habits and meaningful habits
• Compulsive habits and non-compulsive habits

Thumb Sucking Habit:

• Thumb Sucking Habit Etiology:
• Avoidance of parents
• Working mothers provide less time to the child’s nour¬ishment
• With siblings, child may feel neglected by the parents
• The insecurity felt by the children
• Weaning of bottle feeding
• Age: neonate feeling insecurity develop a habit of thumb sucking

Effects On Oro Facial Complex:

• Labial tipping of maxillary anterior
• Proclination of maxillary anteriors
• Increased overjet
• Lingual tipping of mandibular anterior
• Anterior open bite
• Supra eruption of posteriors
• Narrowing of the maxillary arch
• Hypotonic upper lip
• Hyperactive mentalis activity

Thumb Sucking Habit Management:

1. Psychological approach:

• Dunlops beta hypothesis
• Dunlop suggests that the child should be asked to sit in front of the mirror and to suck his thumb
• This becomes effective when the child is asked to do it when he is engaged in an enjoyable activity

2. Mechanical aids:

• Habit-breaking appliances:
  • Passive removable appliances are a palatal crib and clasps on posteriors create interference during habit
• Fixed appliances:
  • Bands on molars fabricated by heavy gauge stainless steel wire
• Other aids:
  • Bandaging the thumb
  • Bandaging of elbow

3. Chemical aids:

• Pepper
• Quinine
• Asafoetida

Question 5. Define and classify space maintainers. Describe fixed space maintainers for bilateral loss of deciduous teeth.
Answer:

Space maintainers Definition: Space maintainers can be defined as appliances used to maintain space or regain minor amounts of space lost, so as to guide the unerupted tooth into a proper position in the arch.

Space maintainers Classification:

• Removal Space Maintainers
• Fixed Space Maintainers
• Space maintainers for bilateral loss of Deciduous teeth

1. Band and Loop:

• The loop is solder to the band
• It should contact the mesial abutment at the contact point
• The band is used for anchorage over the distal abutment
• Space present within the loop permits the eruption of underlying permanent teeth

2. Lingual Arch:

• Stainless steel wire is adapted over the lingual surfaces of teeth
• Bands are anchored over the first permanent molar
• Wire is soldered to the band

Variations:

• Looped lingual archwire
• Lingual horizontal tube
• Ellis loop lingual archwire
• Lingual arch with canine spur

3. Distal shoe space maintainer: Introduced by Willet

Distal shoe space maintainer Design:

• Depends on the distance between the distal surface of the primary molar to the mesial surface of permanent molar
• The crown is fabricated over the permanent molar
• It has a mesial gingival extension
• This extension should be constructed to extend 1 mm below the marginal ridge
• Such an extension guide the eruption of underlying permanent teeth.

4. Nance palatal arch/nance Space holding appliance:

• Consists of bands on the upper molars
• Extend the wire from the lingual surfaces to the deepest and most anterior point in the middle of the hard palate
• An acrylic button is present on the slope of the palate

Question 6. Describe the classification, etiology, and effects of tongue thrusting habit. Write about its management.
Answer:

Tongue thrusting habit Classification:

• Physiologic – Comprises normal swallowing
• Habitual – Present even after correction
• Functional – Adaptive function
• Anatomic – Persons having a large tongue

Tongue thrusting habit Etiology:

• Persistence of infantile swallowing pattern
• Presence of upper respiratory tract infection
• Motor disability
• Missing incisors
• Bottle feeding
• Presence of other oral habits
• Macroglossia
• Hereditary

Tongue thrusting habit Effects:

1. Extraoral:

• Incompetent lips
• Backward mandibular movement
• Speech problems
• Increase in anterior facial height

2. Intraoral:

• Anterior open bite
• Increase in overjet
• Proclamation of interiors
• Posterior open bite
• Posterior crossbite

Tongue thrusting habit Management:

1. Myofunctional exercises:

• Ask to position the tongue in the rugae area for 5 minutes and swallow
• Place the tongue on the spot, salivate, squeeze against the spot, and swallow

2. Pre-orthodontic trainer:

Tongue tags are used to position the tongue while tongue guards prevent the habit

3. Speech therapy:

• Ask the child to repeat simple multiplication tables of sixes
• Ask the child to pronounce words with ‘S’ sounds

4. Mechanotherapy:

• Nance Palatal Arch Appliance:
  • The acrylic button of the appliance used to guide the tongue in position
• Removable Appliance:
  • Hawley’s appliance is used with modifications
  • They are
    • Absence of acrylic portion from gingival mar¬gin of lingual surfaces of maxillary anterior
    • The crib is incorporated, its loops are reduced gradually as the patient starts correct positioning of the tongue
• Fixed Appliance:
  • Crowns and bands over first permanent lar along with lingual bar “
• Oral Screen:
  • Modified with the addition of wire loop bar¬rier to prevent tongue thrusting

5. Surgical treatment: Orthognathic surgical procedures are carried out

Malocclusions Short Essays

Question 1. Myofunctional appliances.
Answer:

Definition: Defined as loose fitting/passive appliances which harness natural forces of orofacial musculature, that are transmitted to teeth and alveolar bone.

Myofunctional appliances Uses: Intercept and treat jaw discrepancies

Myofunctional appliances Changes:

• Increase/decrease jaw size
• Change spatial jaw relationship
• Changes direction of jaw growth
• Accelerates desired growth

Mode Of Action Of Functional Appliance.

• Force Application

• Force Elimination by
  • Bite planes – Effects:
    • Disocclude the posterior teeth
    • Differential eruption of posteriors
    • Intrusion of incisors
    • Downward and backward mandibular rotation
    • Reduces mandibular prognatism
  • Shields/Screens – Effects:
    • Prevents muscular forces on dental alveolar structures
    • Allows unrestricted growth of the jaw
  • Construction bite – Effects:
    • Displaces mandible from its rest position
    • Stretches muscles
    • Displaces mandible in the sagittal and transverse plane

Question 2. Mixed dentition analysis.
Answer:

Moyer’s Mixed Dentition Analysis: To evaluate the amount of space available in the arch for erupting permanent canine and premolar

1. Mixed dentition analysis Procedure:

Mixed dentition analysis Inference:

• Compare tooth sizes of 3, 4, and 5 and the arch lengths available
• Predicted value > arch length available → Crowding

2. Radiographic method:

• Determine the width of unerupted teeth
• Erupted teeth in a radiograph and on a cast
• Formula Y1 = XI * Y2 / X2
• i.e. Width of the unerupted tooth to be determined
• Width of tooth erupted on cast * Width of tooth erupted on the radiograph
• Width of erupted tooth in the oral cavity on the radiograph

Question 3. Nance’s Arch Holding Appliance.
Answer:

Nance’s Arch Holding Appliance Indications:

• Bilateral loss of deciduous molars
• Combined with habit-breaking appliances

Nance’s Arch Holding Appliance Contraindications:

• If either of the molars has not erupted
• Palatal lesions

Nance’s Arch Holding Appliance Disadvantages: Tissue hyperplasia and infection due to poor oral hygiene

Nance’s Arch Holding Appliance Design:

• Consists of bands on the upper molars
• Extend the wire from the lingual surfaces to the deepest and most anterior point in the middle of the hard palate
• An acrylic button is present on the slope of the palate

Question 4. Clinical Features of Mouth Breathing.
Answer:

Extraoral

• Increased facial height Increased mandibular plane
• Retrognathic mandible
• Long and narrow face
• Narrow nose
• Short and flaccid upper lip
• Speech deformities
• Decreased sense of smell and taste

Intraoral

• High palatial vault
• Retroclined interiors
• V-shaped palate
• Posterior crossbite
• Constricted maxillary arch
• Decrease overbite
• Hyperplastic gingiva
• Marginal gingivitis
• Deep pockets

Question 5. Band and Loop.
Answer:

Band and Loop Indications:

• Premature loss of primary first molar
• Unerupted premolar

Band and Loop Contraindications:

• Extreme crowding
• High caries activity

Band and Loop Modifications:

• Loop on only one side of the arch
• Addition of occlusal rest to prevent slippage of appliance gingivally
• Fabrication of a crown instead of a band
• Reverse – by the anchoring band on the mesial abutment

Question 6. Space Regainers./Fixed space regainers.
Answer: Appliances used to regain the space lost due to early loss of primary teeth are called space regainers.

1. Fixed Space Regainers:

• Open Coil Space Regainer:
  • The molar band is fitted to the 1st permanent molar
  • Molar tubes are soldered over it
  • Stainless steel wire is bent into U shape
  • Select the open coil spring and it is slide on the wire

2. Gerber Space Maintainer:

• U assembly welded to the tube is fitted in the tube
• U bend contact the tooth mesial to the edentulous area

3. Horizontal lingual arch:

• The wire is adapted along the lingual surfaces of teeth
• Canine spurs are added to it

4. Lip Bumper:

• The wire is adapted along the labial surfaces of teeth
• U bent is incorporated just before it enters the mo¬lar tube
• The acrylic portion is present in the anterior region

5. Removable Space Regainer:

• Free End Loop:
  • Labial wire with a back action loop spring is used
• Split Block:
  • Acrylic block is splittedbuccolingually and joined by wire in the form of a loop
• Slingshot:
  • Wire elastic holder with hooks is used
• Jack screw:
  • Incorporate and expand screw

Question 7. Crossbite.
Answer: It is an abnormal labiolingual relationship between one or more teeth

Crossbite Classification:

• Anterior and Posterior
• Unilateral and Bilateral
• True and Functional
• Combination

Crossbite Causes:

• Tooth size-jaw size discrepancy
• Skeletal discrepancy
• Palatally placed teeth
• Supernumerary teeth
• Presence of any pathology
• Decreased muscle tone
• Ectopic eruption
• Cleft palate
• Premature contacts
• Mouth breathing habit

Crossbite  Treatment:

• Anterior Crossbite:
  • Removal of premature tooth contact:
  • Tongue blade therapy:
    • Lower incisors are used as fulcrums
    • The tongue blade is placed at 45° behind the tooth
    • Push the locked teeth
    • Used for 1-2 hours daily for 10-14 days
  • Lower inclined plane:
    • Catlan’s Appliance:
      • An acrylic inclined plane is fabricated
      • It is cemented over the lower anterior teeth
      • It is fabricated at 45° to the long axis of the lower incisors
  • Stainless steel crown: For lower incisor
  • Composite inclines: Build up over lower teeth
  • Removable Hawley’s appliance:
    • Adam’s clasp over molars
    • Z springs incorporated into acrylic resin
  • Fixed appliances:
    • Auxiliary springs used along lingual or palatal arches
• Posterior Crossbite
  • Occlusal equilibrium: Removal of occlusal interfer-ences
  • Removable W arch appliance:
  • Cross elastic appliance:
    • Bands are adapted over teeth
    • A hook is welded to bands to engage elastic
  • Removable Hawley’s appliance:
    • Skeletal Correction: Use of expansion appliances

Question 8. Midline Diastema.
Answer: It is the spacing present between the maxillary anterior

Midline Diastema Etiology:

• Ugly duckling stage
• Thumb sucking habit
• High frenum attachment
• Supernumerary teeth i.e. mesiodens
• Tooth size – a material discrepancy
• Presence of pathology

Midline Diastema Treatment:

1. Removable appliances:

• Acrylic plate along with finger springs
• Hawley’s appliance
• Split labial bow

2. Fixed appliances:

• Closed coiled springs
• M shaped elastic

 

Question 9. Anterior crossbite.
Answer:

Anterior crossbite Definition: It is defined as malocclusion resulting from the lingual position of the maxillary anterior teeth in relationship with the mandibular anterior teeth.

Anterior crossbite Etiology

• Persistence of deciduous teeth
• Arch length- tooth material discrepancy
• Presence of habits such as thumb-sucking and mouth breathing
• Retarded development of the maxilla
• Narrow upper arch
• The collapse of the maxillary arch
• Unilateral hypo or hyperplastic growth of any of the jaws

Anterior crossbite Management

1. Use of removable appliances

• Use of tongue blade
  • It is used to treat single-tooth anterior crossbite
  • It resembles ice cream stick
  • It is placed inside the mouth contacting the palatal aspect of the tooth in crossbite
  • Rest the blade on the mandibular tooth
  • The patient is asked to rotate the oral part of the blade upwards and forward
  • Repeat the exercise for 1-2 hours for about 2 weeks
• Catlan’s appliance
  • It is a lower inclined plane constructed on a maxillary arch
  • Have 45° angulation
  • Forces the maxillary teeth to a more labial position
• Use of Z spring
  • Used to treat anterior cross bites involving one or two maxillary teeth
  • Used when there is adequate space for labialization

2. Use of fixed appliances

• Multilooped archwires or nickel-titanium archwires are used for corrections
• Indications
• Dental anterior crossbites involving one or more teeth
• Requirement of more tooth movement along with correction of crowding and rotations
• Patients who exhibit minimal overbite

Malocclusions Short Answers

Question 1. Gebner’s space regainer.
Answer:

• Gerber appliance may be fabricated directly in the mouth or in a relatively short appointment period and requires no lab work
• A seamless orthodontic band or crown is selected for the tooth to be destabilized
• This space regainer consists of U-shaped hollow tubing soldered or welded to the mesial aspect of the first molar to be moved distally
• U-shaped rods with open coil springs of adequate length are fitted into the above tubing so that they contact the mesial aspect of the first molar to be moved distally
• The forces generated by compressed coil springs bring about a distal movement of the first molar

Question 2. Inclined Plane/Catlan’s appliance.
Answer:

Inclined Plane Use:

• Treatment of anterior crossbite
• Palatally displaced maxillary incisor

Inclined Plane Design: Acrylic/metal covering the maxillary incisor at 45° angulation

Inclined Plane Disadvantage:

• Problem in speech
• Dietary restriction
• Supra eruption of posteriors

Question 3. Treatment of Anterior Crossbite.
Answer:

Crossbite: Condition where one/more teeth may be malposed abnormally, buccally or lingually or labially with reference to the opposing tooth/teeth.

Crossbite Classification:

• Single tooth crossbite
• Segmental cross bite

Crossbite Treatment:

• Use of tongue blade
• Catlan’s appliance
• Z spring
• Screw appliances
• Face mask
• Frankel 3
• Chin cup appliances

Question 4. Space Regainers.
Answer: Appliances used to regain the space lost due to early loss of primary teeth are called space regainers.

1. Fixed Space Regainers:

• Open Coil Space Regainer
• Gerber space maintainer
• Horizontal lingual arch
• Lip bumper

2. Removable space regainers:

• Free end loop
• Split block
• Slingshot
• Jack screw

Question 5. Lingual arch space maintainer.
Answer: It is a fixed, non-functional, passive mandibular arch appliance

Lingual arch space maintainer Indications:

• Bilateral loss of posterior teeth
• Minor movement of the anterior teeth
• Maintenance of leeway space
• Space regaining

Lingual arch space maintainer Contraindications: Before the eruption of the mandibular incisors

Lingual arch space maintainer Disadvantages:

• Loss of cementation and solder
• May cause untoward movement

Question 6. Oral Screen.
Answer: Introduced by Newell in 1912

Oral Screen Principle:

• Application of muscular forces to teeth or
• Elimination of forces to teeth

Oral Screen Indications

• Interception of habits
• Treatment of mild malocclusion
• For muscular exercises
• Correction of mild anterior proclamation

Question 7. Transpalatal arch.
Answer:

Transpalatal arch Indications Unilateral space loss

Transpalatal arch Contraindications Bilateral space loss

Transpalatal arch Appliance:

• Used in the maxillary arch
• Wire crosses the palate
• Bands are fabricated over molars
• Wire are soldered to the bands

Question 8. Lip Bumper.
Answer: Combined removable fixed appliance

Lip Bumper Mode Of Action: Force application/elimination

Lip Bumper Uses:

• Interception of lip-biting habits
• Increases arch length
• Reduces crowding
• In the case of hyperactive mentalis activity
• For augmentation of anchorage
• For visualization of 1st molar
• Used as space regainer

Lip Bumper Designs:

• Stainless steel wire from one molar to the opposite molar passing away from anterior
• An acrylic portion from canine to canine

Question 9. Angle’s Classification.
Answer:

• Class 1 – The mesiobuccal cusp of the upper first permanent molar coincides with the mesial groove of a lower first permanent molar.
• Class 2 – The distobuccal cusp of the upper first permanent molar coincides with the mesial groove of the lower first permanent molar
• Class 3 – The mesiobuccal cusp of the upper first permanent molar coincides interdentally between the lower first and second permanent molar

Question 10. Factors considered before placement of space maintainers.
Answer:

• Patient’s cooperation
• Appliance integrity
• Space required
• Space available
• Position of incisors
• Crowding severity
• Depth of curve of Spee
• Position of midline
• Leeway space

Question 11. Tanaka and Johnston Analysis.
Answer:

• Half the mesiodistal width of 4 lower incisors + 10.5 = Mandibular 3 + 4 + 5 in one quadrant
• Half the mesiodistal width of 4 lower incisors + 11.0 = Maxillary 3 + 4 + 5 in one quadrant

Question 12. Masochistic Habits/Self-Mutilating Habits.
Answer: Repetitive acts that result in physical damage to the individual

Masochistic Habits Etiology:

• Syndrome associated
• Superimposed on a pre-existing lesion
• Secondary to habit
• Unknown etiology

Masochistic Habits Types:

• Frenum thrusting
• Bobby Pin Opening

Question 13. Bruxism
Answer: It is a habitual grinding of teeth either during sleep in the night or unconsciously during day time.

Bruxism Causes:

• Occlusal disturbances
• Emotional disturbances
• Occupational

Bruxism Features:

• Attrition of teeth
• Loosening and drifting of teeth
• Gingival recession
• Hypertrophy of muscles
• Sensitivity of teeth
• Facial pain
• Trismus

Bruxism Treatment: Use of occlusal splints

Question 14. Inclined plane
Answer:

Inclined plane Use:

• Treatment of anterior crossbite
• Palatally displaced maxillary incisor

Inclined plane Design:

Acrylic/metal covering the maxillary incisor at 45o angulation

Inclined plane Disadvantage:

• Problem in speech
• Dietary restriction
• Supra eruption of posteriors

Question 15. Dunlop’s beta hypothesis
Answer:

• It is used for thumb-sucking habit
• Dunlop suggests that the child should be asked to sit in front of the mirror and to suck his thumb
• This becomes effective when the child is asked to do it when he is engaged in an enjoyable activity

Malocclusions Viva Voce

1. Space maintainers are contraindicated in crowded occlusions
2. Nance is called the father of serial extraction
3. A lip bumper is also called a modified vestibular screen
4. Maximum space is lost during six months of extraction
5. Space regained by space regainers should be maintained until adjacent permanent teeth have erupted completely
6. Reverse band and loop is indicated where there is premature loss of the primary second molar and the permanent molar have not erupted fully
7. A lingual arch space maintainer is the most effective appliance of space maintenance and minor tooth movement in the lower arch
8. Self-injurious habits are also called masochistic habits
9. Masochistic habits have a higher incidence in mentally retarded children
10. Nail biting is a sign of internal tension
11. Mouth breathing habit is diagnosed by mirror test, water holding test, butterfly test, and rhinometry.
12. Tongue thrusting habit often self-corrects by 8-9 years of age
13. Bluegrass appliance is used to manage thumb suck-ing habits in children between 7-13 years of age