Root resorption involving internal and external root resorption

1. Root resorption

2. Presented By:- Dr Nishant
Khurana
PG Student9/26/2013 2

3. classification
1. External root resorption
2. Internal root resorption

4. External root resorption
1. Resorption due to stimulus lasting a short duration (transient
stimulus) –Trauma
1. Surface resorption
2. Inflammatory resorption
3. Ankylosis related resorption
2. Resorption due to a long-lasting (progressive) stimulus
a) Pressure
b) Orthodontic force
c) Tumor and impactions
d) pulpal infection
e) sulcular infection

5. Root Resorption due to Dental Trauma
1. Surface resorption
2. Inflammatory resorption
3. Ankylosis related resorption

6.  General principles
1. Protective mechanisms against resorption
 Unlike deciduous teeth, permanent teeth rarely undergo root
resorption
 Even in the presence of peri-radicular inflammation, resorption will
occur primarily on the bone side of the attachment apparatus and
the root will be resistant to it.

7. Theories
1. The remnants of the epithelial root sheath surround the root like a
net, therefore imparting a resistance to resorption and subsequent
ankylosis.
2. Based on the premise that the cementum and predentin covering on
dentin are essential elements in the resistance of the dental root to
resorption.
a) It has long been noted that osteoclasts will not adhere to or resorb
unmineralized matrix.
b) Major mediators of osteoclast binding are bound to calcium salt
crystals on mineralized surfaces.
c) Since the most external aspect of cementum is covered by a layer
of cementoblasts over a zone of non-mineralized cementoid, a
surface that provides satisfactory conditions for osteoclast
binding is not present.
d) Internally, the dentin is covered by predentin matrix, which
possesses a similar organic surface.

8. 3. cemental layer inhibits the movement of toxins if present in the root
canal space into the surrounding periodontal tissues.

9. Requirements for the presence of root resorption
1. The loss or alteration of the protective layer
2. Inflammation must occur to the unprotected root surface.

10. 1. Loss or alteration of the protective layer
 directly due to the trauma of a dental injury
 indirectly,when an inflammatory response occurs as a result of a
dental injury.
 Physical damage to the cemental layer will only occur at the
specific points where the force of the trauma pushed the tooth
directly against the bony socket .
 Most injury root surface intact.
 The only exception to this rule is an intrusive injury deleterious
effect

12.  In avulsion :
 if the periodontal ligament cells remaining on the root are allowed to
dry out before replantation, they will provide the stimulus for an
inflammatory response over the entire root surface,which, in turn,
results in extensive damage to the protective layer.

13. 2. The inflammatory response
a) The destructive phase.
 active resorption of the dried-
out cells by multinucleated
giant cells takes place
 present as long as stimulus for
inflammation is present
foreign materials or bacteria.
 Short or long standing
stimulus

14. b) Healing phase
1. Surface resorption
2. ankylosis

15. 1. Surface resorption
 The critical factor in
determining the outcome
after a dental traumatic
injury has occurred is the
type of cells that repopulate
the root surface during the
healing phase.
 If cementoblasts are able to
cover the damaged root
surface, a type of healing
termed cemental healing or
surface resorption will occur
and the outcome will be
favorable.

16. 2. replacement resorption
or osseous replacement
 If, on the other hand, bone
producing cells are able to
cover the root surface, the
conditions for healing will
be unfavorable, as direct
contact with bone and
root will occur over some
areas of the root surface; a
phenomenon termed as
ankylosis.
 This process is termed as
replacement resorption
or osseous replacement.
 destruction of over 20%
of the root surface

17. Ankylotic root resorption (dento-alveolar Ankylosis)
 Etiology
1. Traumatic injuries severe cases of intrusion and avulsion
 Bone comes into contacts with the root surface.

18. mechanism:
 Remodeling of bone occurs i.e. dentin is replaced by bone

19.  Clinical feature
1. Lacks physiologic mobility
2. Metallic percussion sound
3. Infra-occlusion
 Radiographic feature
1. lacunae filled with bone.
2. PDL space missing

21. Treatment strategies

22.  The etiology and the prognosis based on the injury

23. TREATMENT MODALITIES
1. Prevention of the initial injury.
2. Minimizing additional damage after the initial injury.
3. Pharmacological manipulation (shut down) of the initial
inflammatory response.
4. Possibly stimulating cemental, rather than bone healing.
5. Slowing down the osseous replacement when it is inevitable.

24. 1. Prevention of the initial
injury.
 Mouth guards.
2. Minimizing additional damage
after the initial injury.
 Tooth should be gently
repositioned back.
 If splinting is necessary it
should be performed with a
functional splint for 7–10
days .

25.  Most importantly, the splint
should be constructed to allow
adequate cleaning, thereby
minimizing the wicking of
bacteria from dental plaque into
the blood clot between the tooth
and the socket wall.
 avulsed toothExtraoral time &
Medium of transport.

26. 3. Pharmacological manipulation (shut down) of the initial
inflammatory response.
a) Tetracycline-local and systemic
 sustained antimicrobial effects
 possess anti-resorptive properties specifically, it has a direct
inhibitory effect on osteoclasts and collagenase.
b) Glucocorticoids (dexamethasone and ledermix)
 reduce the deleterious effects of inflammatory responses
 more specifically, they have been shown to reduce osteoclastic
bone resorption.

27. 4. Possibly stimulating
cemental, rather than
bone healing.
 Emdogain A 
a) makes the root more
resistant to resorption
b) but also stimulates the
formation of new PDL
from the socket.
 BMP

28. 5. Slowing down the inevitable osseous replacement.
 For avulsion injuries with extended dry times, the methods
described below are presently appropriate and accepted:
1. All remaining periodontal ligament debris is removed from the root
by thorough curettage or with the use of acid.
2. Fluoride has been shown to effectively slow down remodeling of
the root to bone and the root is soaked in fluoride for 5 min before
replantation.
3. Bisphosphonates are drugs that have been found to slow down
osteoporosis in post-menopausal females.Its effect is not proven to
be superior to the effect of topical fluoride.
4. Emdogain A can be used.

29. Resorption due to a long-lasting (progressive) stimulus
1. pulpal infection
2. sulcular infection
a) invasive cervical resorption
b) Periodontal infection root resorption
3. Pressure
a. Orthodontic force
b. Tumor and impactions

30. Pulpal infection
 Apical periodontitis with apical root resorption.
2. Lateral periodontitis with root resorption

31. 1. Apical periodontitis with apical root resorption
 The pulp of the tooth can become necrotic
 Bacterial challenge through caries.
 Trauma
 Mechanism
 The inflammatory stimulators will contact the surrounding
periodontal attachment through openings from the pulp to the
periodontium ie either through the apical foramina or,occasionally,
through accessory canals.
 Invariably, the periodontal inflammation is accompanied by slight
resorption of the root at the cemento- dentinal junction.
 This resorption is usually not apparent radiographically but is
routinely observed in a histological evaluation.

32. 2. Lateral periodontitis with root resorption
 When the root loses its cemental protection, lateral periodontitis
with root resorption can result
 Pulp  necrotic due to trauma.
 Cemental covering also lost due to trauma.
 mechanism
 This means that bacterial toxins can now pass through the dentinal
tubules and stimulate an inflammatory response in the
corresponding periodontal ligament.
 The result of this is the resorption of the root and bone.
 Multinucleated giant cells resorbs the denuded root surface and this
continues until the stimulus (pulp-space bacteria) is removed

34.  Radiographic feature
 Radiographically, the resorption is observed as progressively
radiolucent areas of the root and adjacent bone.

36. Treatment
1. Prevention of pulp space infection
2. Prevent root canal infection by root canal treatment at 7–10
days.
3. The elimination of pulp space infection

37. Treatment
1. Prevention of pulp space infection
A. Maintain the vitality of the pulp. Why?
 If tooth vital  bacteria will be absentgood prognosis
 Attempt for revasculariztion (. 1.1 mm wide radiographically).
Avulsed tooth
 revascularization is considered possible if replantation occurs before
60 min of dry time has elapsed.
 For avulsed teeth, soaking it in doxycycline for 5 min before
replantation has been shown to double the revascularization rate.

38. 2. Prevent root canal infection by root canal treatment at 7–10
days.
3. The elimination of pulp space infection.
 Pulpectomy and CH or activ points as medicaments.

40. Sulcular infection
1. invasive cervical resorption
2. Periodontal infection root resorption

41. Sulcular infection
 This progressive external root resorption, which is of inflammatory
origin, occurs immediately below the epithelial attachment of the
tooth.
 Mechanism(pathogenesis)
 since its histological appearance and progressive nature is identical
to other forms of progressive inflammatory root resorption (i.e. an
unprotected or altered root surface attracting resorbing cells and an
inflammatory response maintained by infection).
 Causes of the root damage immediately below the epithelial
attachment of the root include orthodontic tooth movement, trauma,
non-vital bleaching etc
 The pulp plays no role in cervical root resorption and is mostly
normal in these cases.

42.  Because the source of stimulation (infection) is not the pulp, it has
been postulated that it is the bacteria in the sulcus of the tooth that
stimulate and sustain an inflammatory response in the periodontium
at the attachment level of the root .
 similar to marginal periodontitis
 The same resorptive process can occur in other tooth locations
1. In erupting teeth it may arise through an enamel defect in the tooth
crown and may be termed invasive coronal resorption.
2. while a more apical source may be termed
invasive radicular resorption.

43. 1. odontoclastoma
2. idiopathic external resorption
3. fibrous dysplasia of teeth
4. burrowing resorption
5. peripheral cervical resorption
6. late cervical resorption
7. Cervical external resorption
8. extra-canal invasive resorption
9. supraosseous extra-canal invasive resorption
10. peripheral inflammatory root resorption
11. Invasive cervical resorption
12. subepithelial inflammatory root resorption
13. periodontal infection resorption

44. Etiology

45. Classification
 Heithersay has classified this type of resorption into four classes in
order of severity.
•Class 1
•Denotes a small invasive resorptive
lesion near the cervical area with
shallow penetration into dentine.
•Class 2
•Denotes a well-defined invasive
resorptive lesion that has
penetrated close to the coronal pulp
chamber but shows little or no
extension into the radicular dentine.

46. • Class 3
• Denotes a deeper invasion of
dentine by resorbing tissue,
not only involving the coronal
dentine but also extending into
the coronal third of the root.
• Class 4
• Denotes a large invasive
resorptive process that has
extended beyond the coronal
third of the root.

47.  Clinical, radiologic and histopathologic features
1. Class 1
 Some early lesions may show a slight irregularity in the gingival
contour associated with a surface defect containing soft tissue
which bleeds on probing.
 A radiograph will usually show a small coronal radiolucency
corresponding to the lesion.

48. 2. Class 2
 pink discoloration of the
tooth crown
 The radiographic image
usually shows a extensive
irregular radiolucency
extending from the
cervical area into the
tooth crown and
projected over the root
canal outline.
 If the lesion is proximally
located the radiographic
image will show a
radiopaque line bordering
the pulp space.

50.  Histopathologic investigation
 The resorption cavity filled with a mass of fibrous tissue, numerous
blood vessels and clastic resorbing cells adjacent to the dentine
surface.
 A thin layer of dentin and predentin is present, separating the
inflammation free pulp from the actively resorbing tissue, which is
also devoid of acute or chronic inflammatory cells.
 The presence of the apparently protective predentin,dentin layer
explains the asymptomatic nature of invasive cervical resorption at
this stage.

51. 3. Class 3
 Clinically, the crown of an
involved tooth may show a pink
discoloration, and there may be
cavitation of the overlying
enamel.
 The radiographic appearance
generally shows an irregular
mottled, or ‘moth-eaten’ image
in the main lesion area and the
outline of the root canal can be
seen as a radiopaque line
demarcating the root canal from
the adjacent irregular
radiolucency

52. 4. Class 4
 The crown displayed a pink
discoloration in the
cervical region.
 The radiograph shows, in
addition to the irregular
outline of the resorptive
process in the tooth crown,
radiolucent lines extending
alongside the pulp space
into the apical third of the
root.

53.  Non-surgical treatment
1. Classified as
 External approach
 External – internal approach
2. Orthodontic extrusion  restoration
 Surgical management
1. Flap reflection followed by restoration
2. Apically displaced flap
3. GTR

54. 1. Non-surgical treatment
 Topical application of a 90% aqueous solution of trichloracetic
acid to the resorptive tissue, curettage, endodontic treatment where
necessary, and restoration with glass-ionomer cement.
 Adjunctive orthodontic extrusion was also employed in some
advanced lesions.
 Classified as
a) External approach
b) External – internal approach

55. a
b
c
g
f
ed
Class
2

56. Class
3

57. Class 3
A. Orthodontic extrusion
1. improves access to the base of the resorption cavity
2. provides a supragingival margin for the restoration
 Method
1. Extrusion is usually effected over 4–6 weeks, using a light wire
technique, and this is followed by splinting, pericision,
gingivoplasty and finally restoration.

58. Surgical management
1. Involves periodontal flap reflection, curettage, restoration of the
defect with amalgam ,composite resin , glass-ionomer cement
,MTA and repositioning the flap to its original position.
 Periodontal reattachment can be expected with MTA be used in this
situation .
2. Apically position the flap to the base of the resorption repair
3. GTR method :
 Rankow  Gortex membrane

60. Prevention of cervical resorption

61. I. Nonvital bleaching.
1. Protection of the dentinal tubules.
 Remove the gutta-percha apical to the cervical line to remove
discolored dentin, but do not extend the preparation into the root.
 Use the crestal bone as a guide.
 Place a layer of cement (IRM, Cavit, glass ionomer) to prevent
ingress of the bleaching agent apically and into the cervical
dentinal tubules.
2. Do not use heat.
 Walking bleaches better than one-sitting thermocatalytic
procedure .

62. 3. Avoid etching the dentin.
4. Do not use Superoxol as it is caustic.
 sodium perborate and water for the walking bleach
II. Orthodontic therapy –monitoring of force.
III. Surgical procedures
IV. Periodontal procedures Procedures that leave the root surface
denuded should be avoided.

63. Periodontal infection root resorption
 Injury to the cementum followed by bacterial infection present in the
periodontium.
 Reasons :periodontal procedures, vital bleaching, trauma,orthodontic
treatment
 Tooth vital.
 Later once the resorptive defect involves pulp tooth becomes non vital

65.  Clinically
 If the resorptive defect
reaches the supra- gingival
portion of the crown a
pink hue is seen due to
granulation tissue
 Radiographically  a
single resorptive defect
seen in the crestal area 
both in tooth and bone.

66. Treatment
 Expose the defect orthodontically or surgically
 Reshape the cavity after removing the granulation tissue
 Restored with composite resin or amalgam.

67.  If involved the pulp or expected
 Root canal treatment followed by the above procedure described done
 Follow up is important

68. Resorption due to Pressure
1. Orthodontic force
2. Tumor and impactions

69. Orthodontic pressure root resorption
 Orthodontically induced inflammatory root resorption (OIIRR) or,
as it is better known, root resorption, is an unavoidable pathologic
consequence of orthodontic tooth movement.
 In most cases, orthodontic tooth movement can be considered a
‘controlled’ trauma where pressure is spread evenly over a root
area, therefore minimizing the inflammatory response, which, in
turn, favors resorption of the bone rather than the root.
 However, in rare cases where the pressure is localized to the apical
region, it can be intense enough to cause cemental damage and
apical root resorption.
 Sterile resorption.

70.  Clinical and radiographic
features
 Tooth vital and asymptomatic
unless very high force is used.
 Located in the apical third
radiographic feature.
 No signs of radiolucency in the
resorbing bone or root
 Cemental healing is favored

71.  Commonly external resorption
 INTERNAL RESORPTION DUE TO ORTHODONTIC
FORCE (1997, BENDER ET AL).
a) Damage takes place at the apex of the tooth near the cemental-
dentinal junction due to the orthodontic pressure.
b) Therefore,protective damage can be either cementum or predentin.
c) Because the predentin can also be affected, it is not unusual to see
radiographic evidence of internal apical resorption during the active
stage of the process.
d) In suggested the term Periapical replacement resorption (PARR)
for describing this type of resorption.

72. •mechanism

73.  There are four degrees of severity of OIIRR:
1. Cemental or surface resorption with remodeling.
2. Dentinal resorption with repair (deep resorption).
3. Circumferential apical root resorption.
4. Ankylosis is not a common sequel of OIIRR.
 Treatment

74. The influence of orthodontic treatment on previously
traumatized permanent incisors
Ilana et al The European Journal of
Orthodontics 1991
The reaction of previously traumatized teeth to orthodontic force
application was investigated.
It can be concluded that the combination of trauma with orthodontic
tipping renders the teeth more susceptible to complications, especially
to root resorption and loss of vitality.
Prevalence and severity of apical root resorption of
maxillary anterior teeth in adult orthodontic patients
A. Davide Mirabella* and Jon Årtun**
The European Journal of Orthodontics 1995
The purpose of this study was to evaluate prevalence and
severity of apical root resorption of maxillary anterior teeth in a large
sample of adult orthodontic patients and to test the hypothesis that
endodontically treated teeth are less likely to experience apical root
resorption.
Evaluation of the teeth with and without endodontic treatment revealed
less resorption of the endodontically treated teeth .

75. A comparison of apical root resorption during
orthodontic treatment in endodontically
treated and vital teeth.
Spurrier SW, Hall SH
Am J Orthod Dentofacial Orthop. 1990
The purpose of this study was to determine
whether vital and endodontically treated incisors
exhibit a similar severity of apical root resorption in
response to orthodontic treatment.
Vital incisors resorbed to a significantly greater
degree than endodontically treated incisors.

76. Influence of Orthodontic Dental Movement on
the Healing Process of Teeth With Periapical
Lesions
Ricardo
The purpose of this study was to
histomorphologically evaluate (in dog’s teeth) the
influence of tooth movement in the healing of chronic
periapical lesions.
The results showed that the orthodontic
movement delayed, but did not hinder, the periapical
healing process.

77. Root resorption after orthodontic treatment of
traumatized teeth
Olle et al j endodon 1990
This study concerns the frequency and degree of root resorption in
traumatized incisors that have been treated orthodontically.
The degree of root resorption in traumatized teeth was compared to
that in the uninjured control teeth in the same patient and in the
patients without trauma.
Neither the intraindividual nor the interindividual comparisons
support the hypothesis that traumatized teeth have a greater
tendency toward root resorption than uninjured teeth.
Traumatized teeth with signs of root resorption prior to orthodontic
treatment may be more prone to root resorption during treatment.

78. Impacted tooth or tumor pressure root resorption
 During eruption of permanent teeth
a) Maxillary canines resorbs lateral incisors
b) Mandibular 3 rd molars resorbs second molars
 Tumors or osteosclerosis impinging on the root.
 tumors slowly progressing like,
 Ameloblastoma
 Fibro-osseous lesions

79. mechanism

80. Clinical and radiographic picture
 Non-symptomatic and vital
 Radiographic feature no radiolucency ,but the causative factor can
be identified

81. Internal root resorption
 Etiology
1. Caries
2. Pulpotomy
3. Orthodontic treatment

82.  Internal root resorption is rare in permanent teeth, and is
characteristized by an oval-shaped enlargement of the root canal
space
 mechanism
1. Characterized by the resorption of the internal aspect of the root by
multinucleated giant cells adjacent to granulation tissue in the pulp.
2. Chronic inflammatory tissue is common in the pulp,but only rarely
does it result in resorption.
3. pulp due to trauma or bacterial invasion inflammation occurs
causes the undifferentiated cells to form dentinoclasts  resorbs
the dentin.
 Etiology  caries,trauma,not using water spray during cavity
preparation , idiopathic.

83. Clinical manifestations
 Asymptomatic and is first recognized clinically through routine
radiographs.
 If perforation of the crown occurs and the metaplastic tissue is
exposed to the oral fluids, pain may be a presenting symptom.
 The coronal portion of the pulp is often necrotic whereas the apical
pulp, which includes the internal resorptive defect, can remain vital.
 The pink tooth.

84. Radiographic appearance
 The usual radiographic presentation of internal root resorption is a
fairly uniform radiolucent enlargement of the pulp canal .
 Because the resorption is initiated in the root canal, the resorptive
defect includes some part of the root canal space.
Treatment
 root canal therapy

85. Diagnostic Features of External vs. Internal Root Resorption
1. Radiographic features
2. Vitality testing
3. Pink spot

86. Radiographic features
A change of angulation of X-rays
 Internal root resorption
 A lesion of internal origin
appears close to the canal
whatever the angle of the X-
ray
 External root resorption
 On the other hand, a defect
on the external aspect of the
root moves away from the
canal as the angulation
changes .
 In addition, by using the
buccal-object rule, it is
usually possible to
distinguish if the external
root defect is buccal or
lingual/palatal.
 Accompanied by bone
resorption.

87. Vitality testing
Internal resorption
 positive response
External root resorption
 In apical and lateral
aspects of the root
involves an infected pulp
space  negative
response.
 Cervical  positive

88. Pink spot
 Internal resorption
 May be seen  if coronal.
 External root resorption
 Cervical  seen in the
case of class 2 ,3 and 4

89. Other causes
1. Extra canal invasive root resorption as a late complication of
radiotherapy to head and neck region (Shah et al)
2. An unusual case of furcation external resorption (P. Wood & J.
S. Rees)
 Occlusal trauma associated with anterior open bite.

90. Conclusion
 Root resorption is one of the common sequela of trauma.
 Other contributing factors like orthodontic treatment , presence
of tumors, pulpal infection, periodontal infection, Occlusal
trauma etc also cause root resorption.
 Knowledge about the various causes and treatment modalities
a clinician can prevent or at least minimize the resorptive
process and thereby increasing the longevity of the tooth.