Interceptive orthodontics refers to early orthodontic treatment during mixed dentition to guide proper development of the dentition. Common procedures include serial extraction to relieve crowding, correction of developing crossbites, and control of abnormal habits like thumb sucking. Early intervention is beneficial as it is simpler and more stable than later treatment, prevents worsening of issues, and offers psychological benefits to children. The optimal age for screening and interceptive treatment is around 9-11 years old.

1. INTERCEPTIVE ORTHODONTICS
BY DR. SHRUTI SUDARSANAN
JUNIOR RESIDENT
DEPT OF PEDIATRIC AND PREVENTIVE DENTISTRY

2. INTRODUCTION
Early orthodontic intervention procedures are carried out
during the stage of mixed dentition when dentition is
forming, permanent teeth are in various stages of
development and the dental arches, dentoalveolar
processes, jaw bones and facial structures are growing.

3. DEFINITION
Interceptive orthodontics have been defined as that phase of the science and art of
orthodontics employed to recognize and eliminate potential irregularities and
malpositions in the developing dentofacial complex.
-American Association of Orthodontists (AAO 1969)
Interceptive orthodontics is defined as the action taken to preserve the integrity of
what appears to be normal occlusion at a specific time. -Graber (1966)

4. BENEFITS AND REASONS FOR EARLY
INTERVENTION
1. Premature loss of primary teeth- can cause a bizarre of
malocclusion. At later stages- complex mechanics required.
2. Early ortho interventions- does not impede normal growth
but guide the developing dentition into normal occlusion
3. Early treatment of habits is simpler than in later stage of life
4. Crowding gets worse if not intervened early

6. 5. Severe rotations of teeth when corrected early are more
stable with less relapse

7. 6. Early management of space in arch: possibility of arch development and
resolve minor crowding
(subjects treated with non-extraction treatment and normal craniofacial
structures show a naturally aesthetic profile.
7. Early occlusal guidance trains the tongue: act like functional appliance and
stimulate normal development of arches

8. 8. Class II malocclusion, often half cusp (3.5mm or less) can be effectively
managed
*favourable growth pattern: low mandibular plane angle and horizontal growth:
more suitable for functional appliance treatment
9. Non compliance of adolescent years can be avoided
10. Early orthodontic treatment offers psychological benefits to children facing
bullying and teasing in school

9. Need For Interceptive Orthodontics
15% of developing malocclusions can be fully corrected in primary/ mixed dentitions with relatively
simple means.
Ackermann and Proffit,1980
1 in 3 community patients assessed as in need of interceptive orthodontics; only 20% of these
underwent interceptive orthodontics.
Al Nimri and Richardson,2000
Sandhu, S.S and Bansal, N and Sandhu, N (2012) Incidence of malocclusion in India: a review journal
oral health comm dent. 6. 21-24

10. TIMING
The most suitable age for screening the child population for
interceptive orthodontics is 9 and 11 years.
-Al Nimri and Richardson,2000
AAO guideline: age 7 (2013)

11. PROCEDURES UNDERTAKEN IN INTERCEPTIVE
ORTHODONTICS
Crowding interception
Serial extraction
Correction of developing cross bite
Control of abnormal habits
Space regaining
Muscle exercises
Interception of skeletal malrelation
Removal of soft tissue or bony barrier to enable eruption of teeth

12. 1. CROWDING

13. Definition
Crowding is defined as a faulty relationship between the mesiodistal diameter of
teeth, jaw size and arch perimeter. Jaw size determine the available space for
teeth apices, arch perimeter determine the available space for teeth crown
while mesiodistal diameter falls in between them.
-Richardson 1999

14. Types of Crowding
• Tooth size and arch size discrepancy, with this ratio
being more often increased
• genetically determined
Primary crowding:
• By premature loss of primary molars
• Environmental in origin
Secondary Crowding
• Has both genetic and environmental contributions
• Main determinant: differential late jaw growth
Tertiary or late lower
incisor crowding

15. RICHTER’S SCALE FOR CROWDING (Clark et al 1977)
Minor
crowding
1-3 mm of
space
deficiency
Moderate
crowding
4-5 mm of
space
deficiency
Severe
crowding
6mm or more
of space
deficiency

16. LITTLE’S IRREGULARITY INDEX
0 Perfect alignment
l-3 Minimal irregularity
4-6 Moderate irregularity
7-9 Severe irregularity
10 Very severe irregularity

17. Will crowding resolve on its own?
Interdental spacing
Spacing in deciduous
anteriors: good sign
of alveolar growth
Eruption of
incisors lateral
shift of deciduous
canines create
space in the arch
Intercanine arch
width
Increases 6mm in
maxilla; 4mm in
mandible (from 2yrs
to age of maturity)
Hagberg (1994):
intercanine distance
28mm or more: little
risk of crowding
<26mm: crowding
may be associated
Inclination of
permanent incisors
Forward inclination
of permanent
incisors  increase
in arch
circumference
Tooth size ratio:
b/w permanent and
primary teethh

18. MANAGEMENT OF CROWDING
Observe: if:
 <2mm crowding
 Space analysis + intercanine width = favourable
Disk primary teeth
Extraction of teeth
 Serial extraction, timely extraction, Wilkinson
extraction etc
 Elective extraction of deciduous canine
Expansion
Referral
Space required: 2-4mm
Grinding/disking the mesial surfaces of canine
169Lbur or disking strip (minimal stripping; better control)
Surface protected with fluoride
Alignment of teeth after space availability
•By tongue pressure
•Laterals locked behind centrals: lingual arch with auxillary springs
Inadequate space after disking:
•Disking of primary molars later
-Sheridan J.J (1985), Philippe (1991), Rosa et al (1994)

19. 2. SERIAL EXTRACTION

20. HISTORY
Concept: BUNON (1743)
Term “serial extraction” : Kjellgren (1929)
Popularised by: Nance (1940) –father of serial
extraction
Now called: Guidance of eruption or “Active
supervision of teeth by extraction”- by Hotz (1970)

21. Definition
Serial extraction is an Interceptive orthodontic procedure usually initiated in the early mixed
dentition when one can recognize and anticipate potential irregularities in the dentofacial
complex and is corrected by a procedure that includes the planned extraction of certain
deciduous teeth and later specific permanent teeth in an orderly sequence and predetermined
pattern to guide the permanent teeth into a more favourable position.
A program of selective or guided extraction of primary and sometimes permanent teeth
over a period of time, with the objective of relieving crowding and facilitating the
eruption of remaining teeth into improved positions. -AAO 2012

22. Indications
Class I with severe crowding and proclination (TSALD of 8mm or more)
Lingual eruption of lateral incisor
Midline shift potential due to unilateral canine loss
Abnormal primary canine root resorption
Lack of developmental spacing
Anomalies such as ankylosis, ectopic eruption
Retrusion X

23. Contraindications
Mild to moderate crowding (8mm or less)
Congenital absence of teeth providing space
Where extensive caries of permanent first molars requires their removal
deep or open bites
Class II/III malocclusion
Cleft lip and palate

24. Assessment
Facial photographs
Clinical examination
Occlusion study (models)
X rays- iopa, opg, ceph

25. Space Analysis For Serial Extraction
Conventional dental oriented
mixed dentition analysis:
Moyers mixed dentition
analysis
A facial oriented analysis,
incorporating the relations of
the incisor teeth to basal bone,
is preferable
Cephelaometric analysis
• Proportional facial analysis
• Steiner classification of facial
pattern
• Total space analysis (Levern
Merrifield)
• Steiner’s: to explain the need to
pts
• Tweed’s: to determine the
permanent tooth extraction

26. Procedure
1. Dewel’s method: (CD4) Removal of deciduous canine → Removal of deciduous 1st molars →
Removal of erupting 1st premolars.
◦ Usually followed in lower arch
2. Tweed’s method: (D4C) Removal of deciduous 1st molars → Removal of erupting 1st
premolars → Removal of deciduous canine.
◦ Followed in either arch
3. Nance method: (D4C) Removal of deciduous 1st molars → Removal of erupting 1st premolars
→ Removal of deciduous canine.

29. Advantages:
1. Further appliance therapy is minimised
2. Reduce the complexity of treatment needed
Disadvantages:
1. Serial extraction followed by fixed appliance
therapy in:
1. Deep bite cases
2. Ditching
2. Selectively used in class II (In alveolodental
protrusion used in maxilla only)
3. Pt cooperation affects treatment
4. Caries in 2nd PM may lead to their removal
5. Impacted canine

30. 4. Wilkinson’s Extraction: elective extraction of all Permanent first molars
5. Elective extraction of 2nd molars - Richardson 1992

31. Timely Extraction- “Stemm”
Sequential removal of deciduous teeth
But no permanent teeth are removed

32. Indications
Gingival recession due to labial positioning of lower incisors + inadequacy of
arch length
Ectopic eruption of lateral incisors or permanent 1st molars
Crowding of 4mm or more: alignment of incisors after permanent canines have
erupted is difficult  EXTRACTION OF DECIDUOUS CANINE

33. 3. CORRECTION OF
DEVELOPING CROSS BITE

34. DEFINITION
The maxillary dentition overlaps the mandibular dentition all
through its perimeter in anterior and buccal segment. This
relationship is called overjet. When the relationship is
reversed, it is termed as crossbite
“the best time to treat a crossbite is the first time it is seen”

35. ANTERIOR CROSSBITE INTERCEPTION
Anterior crossbite can be classified into:
Dento-alveolar anterior crossbite
Skeletal anterior crossbite
Functional anterior crossbite

36. Dentoalveolar Anterior Crossbite
often manifested as single tooth crossbite and usually occurs due to over retained deciduous
teeth

37. Treatment
1. Tongue blade therapy
◦ Simple one tooth crossbite
◦ Erupting stage
◦ Using lower tooth as fulcrum, locked tooth can
be pushed out by placing the tongue blade 450
behind the tooth
◦ Used 1-2hrs daily for 10-14 days

38. 2. Lower inclined plane or Catalan’s appliance
Crossbite involving 1 or 2 teeth
Cemented lower acrylic inclined plane
Contoured and polished at 450 angle to long axis of lower incisor teeth
Steeper the angle , greater the force applied
Weekly review to monitor:
◦ More than 2 or 3 weeks: may open bite
◦ Labial movement of maxillary incisors

39. 3. Double cantilever spring :
For single or multiple teeth in crossbite
Activate the springs 1.5-2mm every 2 weeks
24hr wear
For bite opening : posterior bite plane or glass ionomer turbo
on buccal teeth

40. 4. Reverse Stainless steel crown: for single tooth crossbite
5. Composite inclines: to build a composite or compomer incline on the lower teeth

41. 6. Hawley’s appliance using jackscrew:
to correct anterior crossbite involving all anteriors
Activation: quarter turn every day

42. 7. 2 x 4 fixed appliance

43. 8. Quad helix
Where both maxillary laterals are in crossbite
Free end of anterior arms must contact the lateral
incisors
anterior bridge is placed at the level of distal surface
of canines with anterior helices towards the palate
Posterior helices are placed distal to the first molars
RETENTION PERIOD: at least 3 months

45. Activation
1. extraoralactivation:openingthe helix:
anterior helix:posteriorexpansion(5mm on each molar side)
posteriorhelix:lateral movementof anterior arms anterior
expansion(1.5mm)
2. intraoralactivation:three prong plier:
anteriorexpansion
: posteriorbendis placedon palatal bridge by keepingsingle
prong towards the midline
Posteriorexpansion:anterior bendplace on anterior bridge by
keepingsingle prong anteriorly

46. Functional Anterior Crossbite
The presence of occlusal prematurities deflects the mandible into
a more forward path of closure. So this type of crossbite results
from the functional shift of the mandible.
These are commonly seen in pseudo Class III type of
malocclusion and are treated by eliminating the occlusal
prematurities (careful incisal grinding)

47. Skeletal Anterior Crossbite
This occurs due to skeletal discrepancies in growth of maxilla or mandible.
usually involves the whole segment instead of one or two teeth
It can be because of maxillary retrognathism or mandibular prognathism or both.
best intercepted by growth modification using myofunctional or orthopedic appliances.

48. POSTERIOR CROSS BITE
CAREFUL CLINICAL EXAMINATION AND IDENTIFYING THE ETIOLOGY
1. Occlusal equilibration: to correct crossbite caused by functional interference
2. Cross elastics: for correction of dental unilateral crossbite involving one or
two teeth
◦ Bands are adapted and cemented to teeth involved to which hook or
button is welded. The two teeth are engaged by cross elastic that run
on buccal of upper and lingual of lower molar or vice versa

49. 3. Removable Hawley’s appliance with jackscrew:
Activation: one quarter turn once a week or twice every week
Retention: wear for additional 3-6 months with midline split sealed with
acrylic

50. 4. W arch appliance and quad helix appliance

51. Skeletal Correction
Rapid maxillary expansion (RME): Removable expansion screw or with HYRAX type of expander
The rate of expansion: 1mm/day divided in two instalments: 2 quarter turns (0.5mm) in the morning and
2 in the evening
Expansion lasts for 7-10 days
Orthopaedic forces cause a mid line split of maxilla: midline diastema: successful RME therapy

52. 5. CONTROL OF ABNORMAL HABITS
Definition:
Boucher OC defined habit as a tendency towards an act or an act that has become
a repeated performance, relatively fixed, consistent, easy to perform and almost
automatic

54. GRABER (1976): includes all habit under extrinsic factors
of general cause of malocclusion.
1. Thumb/digit sucking
2. Tongue thrusting
3. Lip/nail biting
4. Mouth breathing
5. Abnormal swallow
6. Speech defects
7. Postural defect
8. Psychogenic habits- bruxism
9. Defective occlusal habits

55. THUMB SUCKING
DEFINITION: Thumb sucking is defined as the
placement of the thumb in varying depths into
the mouth

56. • Normal Thumb Sucking
• Abnormal Thumb Sucking
• Psychological
• Habitual
• Nutritive sucking habits:
• Breastfeeding, bottle feeding
• Non-nutritive sucking habit:
• Thumb or finger sucking, pacifier
sucking
Classification of Thumb Sucking Habit

57. Type A:
•50 percent
•whole digit is placed inside the mouth with the pad of the thumb pressing over the
palate, while at the same time maxillary and mandibular oral contact is present.
Type B:
•13 to 24 percent
•thumb is placed into the oral cavity and at the same time maxillary and mandibular
contact is maintained.
Type C:
•18 percent of the children
•thumb is placed into the mouth just beyond the first joint and contacts hard palate and
the maxillary incisors, but there is no contact with mandibular anterior incisors.
Type D:
•6 percent of the children
•only a little portion of the thumb is placed into the mouth.
According to Subtelny (1973)

58. Theories and Concepts of Thumb Sucking
• Classical Freudian Theory (Sigmund Freud – 1919)
• Oral Drive Theory (Sears and Wise—1982) They suggest that the strength of the oral drive
is in part a function of how long a child continues to feed by sucking. It is not the
frustration of weaning that produces thumb sucking but in fact it is the prolonged nursing
that causes it.
• Rooting Reflex (Benjamin—1962) The rooting reflex is movement of the infant’s head and
tongue towards an object touching its cheeks. He suggested that thumb sucking arises
from the rooting and placing reflexes common to all mammalian infants during the first 3
months of life.
• Sucking Reflex (Ergel—1962) .
• Learning Theory (Davidson—1967)

60. SPACE REGAINING
If a primary molar is lost early and space maintainers are not used, a reduction in
arch length by mesial migration of the 1st molar is expected. In such cases the
space lost by mesial movement of the 1st molar can be regained by distalizing it.

61. Active open coil space regainer
Hotz lingual arch or lower lingual arch
sectional fixed appliances
Lip bumper/plumper
Free end loop space regainer
Split saddle/ split block space regainer
Sling shott space regainer
Jack screw or expansion screw
Anterior space regainer
Kloehn head gear
Jones jig/ pendulum appliance

62. 1. Active open coil space regainer
To regain lost space due to premature loss of second deciduous molar using 1st
premolar as anchorage

63. 2. Hotz Lingual arch or lower lingual arch
• Arch length increased by expanding the u loop by 2mm on either side
• The lingual arch posts are then inserted into tubes
• Review after 1 week and then every 4to 6wks

64. 3. Sectional arch technique
Upto 4mm of space can be regained
4. Lip Bumper/ Plumper:
used where bilateral distal movement of the molars is
needed.
Indicated where lower lip is hyperactive leading to lingual
collapse of incisors

65. 5. Free end Loop Space Regainer
Labial arch wire for retention and stability
Uprighting distal driving spring with helical
Activation in 2-3 weeks
Acrylic clearance in the direction and site of distal movement of
tooth

66. 6. Split Saddle/ split block space regainer
Functional part consists of acrylic block
split buccolingually and joined by wire in
the form of buccal and lingual loop
Activated by periodic spreading of
loops.

67. 7. Sling Shot Space Regainer

68. 8. Jack screw

69. Space regaining using cantilever spring

70. Kloehn Head Gear
Jones Jig/ Pendulum appliance

71. MUSCLE EXERCISES

73. Interception of Skeletal Mal-relations

75. Removal of Soft Tissue and Bony Barriers
Overretained primary teeth, fibrous or bony obstructions, ankylosed primary teeth and supernumerary
teeth are causes of noneruption of succedaneous teeth.
If the permanent tooth fails to erupt because of fibrous or bony obstructions, its eruption may be
stimulated by surgically exposing the crown.
The surgical procedure involves excision of the soft tissue and removal of any bone overlying the crown
of the unerupted tooth. The extent of tissue removal should be such that the greatest diameter of the
crown of the tooth is exposed.

76. CONCLUSION
Thorough understanding of the development process of the dentition,
eruption timings and sequence, establishment of occlusion and its
features is fundamental to diagnosis of a case of potential malocclusion
The mixed dentition period is the greatest opportunity for occlusal
guidance and interception of malocclusion.

77. REFERENCES
1. Graber TM. Orthodontics: Principles and Practice, 3rd Edn. Philadelphia; 1972.
2. Kharbanda OP. Diagnosis and management of malocclusion, 2nd Edn, 2013.
3. Proffit WR. Contemporary orthodontics, 4th Edn, Elsevier publications.
4. S Gowri Shankar. Textbook of Orthodontics, 1st Edn, 2011.
5. Shobha Tondon. Textbook of Pedodontics, 2nd Edn. Paras Medical Publisher; 2009.
6. Nikhil Marwah, textbook Of Pedodontics
7. S.I. Bhalajhi, Orthodontics, The art and science