This document discusses various local factors that can cause malocclusion and interceptive orthodontic treatments for them. It covers delayed eruption of upper incisors, retained primary teeth, infraocclusion, unilateral retained primary canines, double teeth, ectopic eruption of molars, hypodontia, diastema, ectopic eruption of upper canines, thumb sucking, tooth transposition, crowding, and early extraction of first molars. For each topic, it provides definitions and discusses the interceptive treatment options, timing of treatment, and advantages or disadvantages.

1. INTERCEPTIVE
ORTHODONTICS
BY
Dr. Imtiaz Ahmed
BDS, FCPS
Head, Department of Orthodontics,
DIKIOHS. DUHS

2. INTERCEPTIVE
ORTHODONTICS
• Definitions:
Any procedure that eliminates or reduces the
severity of malocclusion in the developing
dentition.(Popovich and Thompson 1979, Hiles
1985.)
All simple measures that eliminate the developing
mal occlusion. (Ackerman and Proffit 1980)

3. INTERCEPTIVE
ORTHODONTICS
The aetiology of malocclusion could be:
1- Skeletal discrepancy
2- Soft tissue
3- local factors
4- Crowding and spacing
5- Displacements

4. INTERCEPTIVE
ORTHODONTICS
Local factors: DELAYED ERUPTION OF UPPER
PERMANENT CENTRAL INCISOR.
• Definition: 1 is considered to be delayed if the
contra-lateral tooth was fully erupted or if teeth
later in the usual eruption sequence were present.
• Interceptive treatment: removal of supernumerary
with or without tooth exposure.
• Treatment timing: as soon as the supernumerary
tooth is detected.

11. INTERCEPTIVE
ORTHODONTICS
Local factors:RETAINED DECIDUOUS
TEETH.
• Definition: the deciduous tooth is
considered to be over retained if it made
enamel contact with its successor.
• Interceptive treatment: extraction.

12. INTERCEPTIVE
ORTHODONTICS
Local factors: INFRAOCCLUSION
• Definition: the tooth loses its vertical position
relative to the adjacent teeth and assumes a
position below the occlusal plane
• Frequent site: lower 2nd
and 1st
primary molars.
• Interceptive treatment: nothing unless the
permanent successor was absent or the
infraoccluded tooth is likely to disappear .

15. INTERCEPTIVE
ORTHODONTICS
Local factors: UNILATERAL RETAINED
DECIDUOUS CANINE.
• Definition: premature loss of one deciduous
canine as a result of early root resorption by
a crowded lateral incisor.
• Interceptive treatment: extraction of the
primary canine on the opposite side of the
arch to preserve the midline.

16. INTERCEPTIVE
ORTHODONTICS
Local factors: DOUBLE TEETH
• Definitions:
Gemination: the attempt of a single tooth
bud to form two distinct morphological
entities.
Fusion: the result of joining two adjacent
tooth buds.

18. INTERCEPTIVE
ORTHODONTICS
Local factors: DOUBLE TEETH
• In the deciduous dentition double teeth are usually
associated with absent permanent successor, or
ectopic or delayed eruption of the permanent
successor if it was present. Treatment therefore
involve the extraction of the malformed tooth.
• In the permanent dentition treatment options are:
Mask, Split and Extract

19. INTERCEPTIVE
ORTHODONTICS
Local factors: ECTOPIC ERUPTION OF
THE PERMANENT FIRST MOLAR.
• Definition: the molar erupts at an angle
mesial to its normal path of eruption.
• Types : reversible and irreversible
• Treatment: extraction of E or distalisation
of permanent molar

22. INTERCEPTIVE
ORTHODONTICS
Local factors: Hypodontia
• Definition: Absent teeth.
• Common teeth: lower 2nd
premolar & upper
lateral incisor.
• Treatment: space closure or space
maintenance for future prosthesis.

26. INTERCEPTIVE
ORTHODONTICS
Local factors:DIASTEMA
• Definition: space between the two upper
central incisors.
• Treatment if indicated: removal of
pathology (supernumerary, odontome,
fraenum?….)

28. INTERCEPTIVE
ORTHODONTICS
Local factors: ECTOPIC UPPER CANINE
• Definition: the canine erupts out of its
normal eruption path.
• Diagnosis: If the 3 was not palpable in the
buccal sulcus after the age of 10 years.
• Treatment: Extraction of the deciduous
canine.

32. INTERCEPTIVE
ORTHODONTICS
Local factors:ECTOPIC UPPPER CANINE
Rate of eruption of the permanent canine after
the extraction of the deciduous canine
depends on the amount by which the
permanent canine overlap the lateral
incisor:
overlap < 12 of lateral root: success rate
91%
overlap > 12 of lateral root: success rate
64%

33. INTERCEPTIVE
ORTHODONTICS
Local factors: THUMB SUCKING
• Effect: no malocclusion 14.6%
anterior open bite 48.1%
posterior cross bite 07.2%
ant OB +post X-bite 30.1%
(Da Silva et al. 1991)

37. INTERCEPTIVE
ORTHODONTICS
Local factors: THUMB SUCKING
• At what age should treatment be started?
-Da Silva et al (1991) “from the 5th
year of age”
-Proffit (1993) “before the eruption of
permanent incisors”
-Houston (1993) “ by 7-8 years of age “
-Mills (1982) “before permanent dentition”
-Larsson (1987) “before pubertal growth spurt”

38. INTERCEPTIVE
ORTHODONTICS
Local factors: THUMB SUCKING
• Treatment:
1- Adult approach.
2- Deterrent appliance.

39. INTERCEPTIVE
ORTHODONTICS
Local factors: TRANSPOSITION
• Definition: unusual type of ectopic eruption were
two permanent teeth have interchanged their
location in the dental arch.
• Frequent sites: upper canine and first premolar
lower canine and lateral incisor.
• Interceptive treatment: extract transposed tooth.
align before canine eruption
• Treatment timing: before eruption of canine.

42. INTERCEPTIVE
ORTHODONTICS
Crowding:
• Treatment:
1-Space management.
2-Molar distalisation.
3-Serial extraction.
4-Premolar extraction.
5-First molar extraction.
6-lower incisor extraction.
7-Second molar extraction.

43. INTERCEPTIVE
ORTHODONTICS
Crowding: SPACE MANAGEMENT.
• Definition: utilization of Lee Way space to
relieve anterior crowding.
• Indications:1- Cl I molar relation ship.
2- E,s are still present in the.
crowded side(s).
3- Mild crowding.

44. INTERCEPTIVE
ORTHODONTICS
Crowding:SPACE MANAGEMENT
• Methods:1-Space maintainer extract E,s
Or
2- Slice the mesial surface of the
deciduous canine and molars
before the eruption of permanent
canine and premolars.

45. INTERCEPTIVE
ORTHODONTICS
Crowding:SERIAL EXTRACTION
• Definition: ”.. The early recognition or
anticipation of a deformity that will occur
unless teeth are removed at a strategic
interval to relieve in intensity the
developing malocclusion.”

46. INTERCEPTIVE
ORTHODONTICS
Crowding:SERIAL EXTRACTION
• Indications:
- The incisors are substantially crowded.
- Age 8-9 years.
- Normal arch relation ship.
- Reduced or normal overbite.
- All permanent teeth are present.
- The first molars should have a good prognosis.
- The first premolars should be closer to eruption
than canines.

47. INTERCEPTIVE
ORTHODONTICS
Crowding:SERIAL EXTRACTION
• Disadvantages:
1- Increasing the overbite.
2- Lingual tipping of lower incisors
3-Retarding future development in arches.
4-Lack of aesthetic fullness of the lips.
5-Rotated incisors do not align spontaneously.

48. INTERCEPTIVE
ORTHODONTICS
Crowding:SERIAL EXTRACTION
• Methods:
1-When the lateral are erupting in a crowded
position, all deciduous canines are removed.
2-When the roots of the first deciduous
molars are half resorbed. They are removed.
3-As soon as the first premolars erupt they are
removed.

49. FIRST MOLAR EXTRACTION
As an interceptive orthodontic
measure

55. FIRST MOLAR EXTRACTION
• Indications:
-At least one permanent first molar have poor
prognosis.
-Crowding in the relevant quadrant.
-The development of second molar roots did not
reach more than half way.
-No other missing teeth in the same quadrant.
-Normal arch relation ship.
-The overbite is not deep.
-The second premolar is contained within the E roots

57. FIRST MOLAR EXTRACTION
• Advantages:
– No need for future prosthesis
– Reduce incisor crowding
– Eliminate buccal segment crowding
– Less chance for third molar impaction.

58. FIRST MOLAR EXTRACTION
• Disadvantages:
– The uncertainty of the final contact point
between the second molar and second premolar.

59. FIRST MOLAR EXTRACTION
0
20
40
60
80
100
Thunold Thilander
good
poor
• Contact point:
• Good result could be
expected in patients:
– Having buccal segment
crowding.
– having third molars.
– First molars were
extracted early.

62. FIRST MOLAR EXTRACTION
• Compensatory extraction:
– Extraction of upper first molar does not
necessitate the compensatory extraction
of lower first molar
– Extraction of lower first molar
necessitates the compensatory extraction
of upper first molar