impacted teeth

2. DEFINITIONS:
IMPACTEDTOOTH
A TOOTH THAT ISCOMPLETELY OR PARTIALLY UNERUPTED & IS
POSITIONED AGAINST ANOTHER TOOTH, BONE OR SOFT TISSUE SUCH
THAT ITSFURTHER ERUPTION ISUNLIKELY DESCRIBED ACCORDING TO
ITSANATOMIC POSITION.
MALPOSEDTOOTH
A TOOTH UNERUPTED OR ERUPTED, WHICH ISIN AN ABNORMAL
POSITION IN THE MAXILLA OR THE MANDIBLE.
UNERUPTEDTOOTH
A TOOTH NOT HAVING PERFORATED THE ORAL MUCOSA.

3. ORDEROFFREQUENCY OFIMPACTION
 Maxillary Third Molars
 Mandibular Third Molars
 Maxillary Cuspids
 Mandibular Bicuspids
 Mandibular Cuspids
 Maxillary Bicuspids
 Maxillary Central Incisors
 Maxillary Lateral Incisors

4. THEORIES OFIMPACTION
Mendelian theory
Evolutionary reduction in thesizeof themaxillaor themandible
Phylogenetic theory
 Evolution of Masticatory habits- leading to
Withdrawal / elimination of stimulus.
 Softer and refined foods/ fibrousfood /
Uncooked meat
Orthodontic theory
Lossof anterior component of force.
Endocrine Imbalance theory
Pathologic theory

5. ETIOLOGY
SYSTEMIC
Prenatal
Heredity
Miscegenation
Postnatal Causes
Rickets
Anemia
Congenital Syphilis
Tuberculosis
EndocrineDysfunctions
Malnutrition
RareCauses
Clediocranial Dysostosis
Oxychephaly
Progeria
Achondroplasia
Cleft Palate

6. LOCAL
Irregular adjacent teeth
Increased Density of surrounding bone
Long standing chronic Inflammation
Lack of spacedueto under developed jaws
Retained primary dentition
Premature lossof permanent dentition

7. COMPLICATIONS ARISING FROMRETAINED
IMPACTEDTEETH
Persistent Local Infections
Acute/ Chronic alveolar abscesses
Pericoronal infections
Chronic suppurativeosteitis
Necrosis
Osteomyelitis
Pathological Resorption of adjacent teeth
Pathological conditions like cysts and tumors
Pain (Facial pain of Unknown origin)
Fractures of the jaws due to weak spot

9. INDICATIONS FORREMOVALOFIMPACTEDTEETH
Recurrent Pericoronitis- (Indicated / contraindicated)
Unrestorable caries
Periodontal disease(prophylactic)
ObscureOro-facial pain
Previousattempted extraction
Prosthetic considerations
Orthodontic considerations

10. PRE-OPASSESMENTOFIMPACTED3RDMOLAR
CLINICAL:-
 Small mouth, mandibular retrusion-limited access
 Largemouth, mandibular protrusion-good access
EXTERNALOBLIQUERIDGE&RELATION TO 3RD MOLAR:-
 Ridgebehind tooth-good access
 Ridgealong tooth-poor access

11. RADIOLOGICALASSESMENTOFIMPACTED3RDMOLARS
Extraoral LateralOblique: -
Showsamount of bonebelow 3rd molar
Orthopantomograph: -
Relation of tooth apex to canal
Intraoral periapical: -
Paralleling cone(Minimal distortion)
Bisecting angle
Access: -
White line of External Oblique Ridge
Vertical- Poor access
Horizontal- Good access

12. WINTERS WAR-LINES
WHITELINE: -
A line drawn along the occlusal surfaces of the 1st, 2nd & the highest point
of thethird molar. ThislineshowstheAxial Inclination of the3rd Molar.
Mesioangular, Distoangular, Horizontal, Vertical.

13. WINTERS WAR-LINES
AMBERLINE: -
A line drawn from the bone distal to the third molar to the Interdental septum
(crest) between the1st and the2nd molar.
Thislineshowstheamount of tooth seen on exposure.

14. WINTERS WAR-LINES
REDLINE: -
A line drawn from the amber line to an imaginary point of application of an
elevator. Denotes the depth at which the tooth lies within the mandible. 5mm-under
G.A., 9mm- extraoral approach.

15. ROOTPATTERN OF3RDMOLAR
Dilacerated, hooked, unfavorablecurvature,
dancing roots,hypercementosed, bulbous
SHAPEOFTHECROWN
Largecrownsdifficult to remove
Small crown easy to remove
TEXTUREOFINVESTING BONE
Increasein age- bonemoresclerosed and lesselastic
Also notesizeof cancellousspaces& density of bonestructure.
POSITION ANDROOTPATTERN OFTHE2NDMOLAR
Distal tilt in 2nd molar - difficult impactio n
Conical roots -mo re chances o f accidental luxatio n

16. RELATION SHIPOFROOTTO CANAL
Related but no t invo lving the canal
Separated
Adjacent
Superimposed
Related to changes in the ro o ts
Darkening of root
Dark and bifid root
Narrowing of root
Deflected root
Related with changes in the canal
Interruption of lines
Converging canal
Diverted canal

17. PELL&GREGORY’S CLASSIFICATION
A. Relation of the tooth to the ramus of the mandible and the second molar
CLASS I
Sufficient amount of spacebetween ramusand distal sideof 2nd molar to accommodate
themesio-distal width of 3rd molar
CLASS II
Spacebetween ramusand distal sideof 2nd molar lessthan themesio-distal width of the
3rd molar
CLASS III
All or most of thethird molar islocated within theramusof themandible.

18. CLASS I CLASS II
CLASS III

19. PELL&GREGORY’S CLASSIFICATION
B. Relative depth of the third molarin the bone.
POSITION A
Highest portion of tooth is on a level with orabove
occlusal line
POSITION B
Highest portion of 3rd molarbelow occlusal line but
above cervical line of 2nd molar
POSITION C
Highest portion of 3rd molarbelow cervical line of
2nd molar

20. POSITION A
POSITION C
POSITION B

21. PELL&GREGORY’S CLASSIFICATION
C. The position of the long axis of the impacted mandibular
third molarin relation to the long axis of the second
molar(Winter’s classification)
 Mesioangular
 Distoangular
 Vertical
 Horizontal
 Inverted
 Buccoangular
 Linguoangular

22. SURGICALMANAGEMENT
John Tomes (1849) – first to describe surgical access
Steps in surgical removal:
Anesthesia
Incision and mucoperiosteal flap
Removal of bone
Tooth removal
Wound debridement
Arrest of haemorrhage
Wound closure
Postoperative follow-up

23. MUCOPERIOSTEALFLAP:
Incision – 3 parts: Anterior, posterior&intermediate limb
Not to be extended too distally-
Bleeding from buccal vessels &otherarteries
Postoperative trismus – temporalis muscle damage
Herniation of buccal fat pad
Damage to lingual nerve (lingual extention)

24. Factors governing planning of incision
Surgical access
Healing of sutured wound – dry socket
Periodontal health of IImolar– distal pocket
Suture line must rest on normal bone
Partly visible crown: de-epitheliazation

26. TYPES OFFLAPS
L– shaped flap
Envelope flap
Bayonet – shaped flap

27. ELEVATION OFTHEFLAP
Good and adequate exposure
Avoid button holing
Understanding of the anatomy in that region
Adequate retraction: self-retaining retractors (thimble)

28. BONEANDTOOTHREMOVAL
Chisel, burorcombination techniques
Burtechnique:
Rose-head bur– Gutteraround the distal and buccal aspect
(Moore &Gilby’s technique)
More amount removed around the point of application
Undercopious saline irrigation – thermal necrosis

29. Chisel technique through buccal approach:
Immobilize mandible – prop
Follow bone trajectories – parallel to long axis of the bone
Vertical stop cut first – 3 to 5 mm distal to IImolar
Oblique cut – removal of wedge to expose the tooth
Furtherremoval forpoint of application

31. LINGUALSPLITTECHNIQUE– KELSEY FRY
Useful forlingually placed IIImolar
Similarincision and limiting cuts
Removal of distolingual bone parallel to ext. oblique ridge
Fracture of the lingual plate – removal of wedge
Tooth elevated lingually
Higherincidence of lingual nerve damage
Advantage: saucershaped cavity – retains clot

33. TOOTHDIVISION TECHNIQUE:
Horizontal, distoangularimpacted teeth
To avoid removal of large amount of bone
Tooth can be divided vertically, horizontally, and obliquely

37. LATERALTREPENATION TECHNIQUE:
Described by Bowdler Henry
Orthodontic purpose– avoid malocclusion
Modified S-shaped incision
Buccal cortical plateistrephined over III molar cr
Tooth removed along with follicle

38. COMPLICATIONS OFREMOVAL:
Dry socket – 10 to 30 %
Damageto inferior alv. canal, lingual & mylohyoid nerves
with impaired sensation – 2 to 3 %
Pocket formation distal to II molar
Infection, pain & swelling – 50%
Damageto adjacent tooth
Deeply impacted tooth in edentulousjaw – fracture

39. IMPACTED
MAXILLARY THIRD MOLARS

40. IMPACTEDMAXILLARY THIRDMOLARS
Classification based on anatomic position:
A. Relative depth of the impacted maxillary third molarin bone:
Class A:
Thelowest portion of thecrown of theimpacted maxillary third molar is
on a line with the occlusal plane of the second molar.
Class B:
Thelowest portion of thecrown of theimpacted maxillary third molar is
between the occlusal plane of the second molarand the cervical
line.
Class C:
Thelowest portion of thecrown of theimpacted maxillary third molar is
at orabove the cervical line of the second molar.

41. IMPACTEDMAXILLARY THIRDMOLARS
B. The position of the long axis of the impacted maxillary third molarin
relation to the long axis of the second molar:
Vertical Inverted
Horizontal Buccoangular
Mesioangular Linguoangular
Distoangular
C. Relationship of the impacted maxillary third molarto the maxillary sinus:
Sinusapproximation (S.A.): no bone, or athin partition
No sinusapproximation (N.S.A.): 2 mm or more

42. CLASS A

43. CLASS B

44. CLASS C

45. SURGICALTECHNIQUE:
Soft tissue flap:
• Incision is made starting beyond the tuberosity in the hamular notch
with No. 12 BPblade.
• The mucous membrane overlying the tuberosity is incised from the
distalmost portion of the tuberosity forward until the midpoint of the
distal surfaceof thesecond molar.
• The incision is continued buccally around the neck of the second molar
to the interproximal space between the first and second molar and then
towardsthe mucobuccal fold at 45-degreeangle.

46. 2. Removal of overlying bone:
 Bonenot dense- can beremoved with chisels/ronguers
 Avoid driving thetooth into thesinus/ pterygomaxillary space
 No need of sectioning
 Exposethecrownsheight of contour
3. Removal of impacted tooth: Useof elevators

51. FACTORS COMPLICATING REMOVAL:
 Maxillary sinus approximation
 Impacted partly within orimmediately above
the roots of the second molar
 Fusion of third and second molarroots
 Abnormal root curvature
 Hyper-cementosis
 Proximity of the zygomatic process of maxilla
 Extreme bone density
 Follicularspace filled with bone
 Trismus

52. IMPACTED
MAXILLARY CUSPIDS

53. IMPACTEDMAXILLARY CUSPIDS
ETIOLOGIC FACTORS:
 Hard palate is more resistant
 Mucoperiosteum of the anterior third of palate is very
dense thick and resistant. Attached more firmly to the
bone
 Eruption is aided by apical development. Canine root
fully formed at the time of eruption
 Greatest distance to travel before reaching full
occlusion.

54.  Caries or premature loss of primary cuspid
 Delayed resorption of primary cuspid
 Last permanent tooth to erupt.
 Erupt between teeth already in occlusion
 Preceded by primary cuspid whose mesiodistal diameter
is much lesser.

55. POSITION OFIMPACTEDMAXILLARY CUSPIDS
Threetimesmoreon thepalatal side
Almost alwaysrotated upon their longitudinal axisand are
usually in an obliqueposition
Horizontal position
Found between first and second molars, nose, sinus, orbit
LOCALIZING IMPACTEDMAXILLARY CUSPIDS
Clinical: Distinct bulge, deflection of crowns
Radiological: IOPA, occlusal view, Shift conetechnique

56. FREQUENTPOSITIONS:
 In thepalate, crown located lingual to theupper lateral incisor
and root extending posteriorly parallel to bicuspid roots
 Crown lingual to central incisor and root extending posteriorly
parallel to thepremolar roots
or
between thepremolar rootsthrough to thebuccal surface
 Crown on thepalatal areaand body of theroot buccally
 Crown on thebuccal surfaceand root palatally
 Entiretooth in thebuccal cortical plate
 Bilaterally impacted either in thepalatal processor labially

57.  In thepalate, crown located lingual to theupper lateral incisor and
root extending posteriorly parallel to bicuspid roots

59. CLASSIFICATION OFIMPACTEDMAXILLARY CUSPIDS
Class I: Impacted cuspidslocated in thepalate
Horizontal
Vertical
Semi vertical
Class II: Impacted cuspidslocated in thelabial or buccal surface
of themaxilla
Horizontal
Vertical
Semi vertical

60. Class III: Impacted cuspids located in both the palatal process
and labial or buccal maxillary bone
Class IV: Impacted cuspids located in the alveolar process
usually vertically between the incisor and first
premolar
Class V: Impacted cuspids located in the edentulous maxilla

61. CLINICALFEATURES:
 Clinically absent in thearch beyond thechronological age
of eruption
 Displacement of adjacent teeth
 Presenceof swelling in thebuccal or palatal mucosa
 Formation of fistula
 Transformation into follicular cyst
 Resorption of adjacent rootsleading to mobility

63. TREATMENTPOSSIBILITIES:
Factors governingmanagement
 Ageof thepatient
 Stageof tooth development
 Position of theimpacted tooth
 Evidenceof root resorption of permanent teeth
 Compliance
Possibilities of treatment:
 Leavein-situ
 Surgical removal
 Surgical exposureof thecrown
 Surgical repositioning
 Surgical transplantation

68. Factors Relatively easy Relatively difficult
1. Pell & Gregory’s Class.
(a)Horizontal plane
(b)Vertical plane
Class I
Position A
Class III
Position C
2. Overlying impediment Soft tissue Bone
3. Crown Small Large
FACTORS RENDERING MADIBULAR III MOLAR SURGERY EASY / DIFFICULT

69. 4. Roots
(a)Formation
(b)Curvature
(c)Morphology
Incomplete
Favourable
Conical / convergent
Complete
Unfavourable
Long, slender, divergent
5. Follicular space Large Thin and small
6. Surrounding bone Elastic or cancellous Dense or cortical
FACTORS RENDERING MADIBULAR III MOLAR SURGERY EASY / DIFFICULT

70. 7. Relationship
(a)II molar
(b)Inf. Alv. Canal
Space distal to
Not related
No space distal to
Related
8. Oral sphincter Large Small
9. Health status Satisfactory Medically comp.
FACTORS RENDERING MADIBULAR III MOLAR SURGERY EASY / DIFFICULT