Hamid Jafarzadeh, DDS, MSc,* and Paul V. Abbott, BDSc, MDS, FRACDS (Endo) Journal of Endodontics — Volume 33, Number 9, September 2007

2. INTRODUCTION
“A tooth with a straight root and a straight root canal is an exception
rather than normal because most teeth show some curvature of the
canals”
Term dilaceration: first used by Tomes in 1848
Dilacero (Latin) = tear up
“Scorpion tooth”
it is defined as “a deviation or bend in the linear relationship
of a crown of a tooth to its root”
According to this definition, dilaceration is thus distinguished
from the rarely used term flexion, which is defined as a tooth with
a hooked or a bent root

3. Tooth dilaceration might present in various ways:
- Non-eruption of the affected tooth,
- Prolonged retention of the primary predecessor tooth,
- Apical fenestration of the labial cortical plate, or
- it can be asymptomatic
If an erupted dilacerated tooth needs root canal treatment, then
the presence of the dilaceration can severely complicate this
treatment

4. ETIOLOGY 2 possible
causes
Mechanical trauma to
the primary
predecessor tooth
Prevalence of traumatic
injuries to the primary
dentition >> Incidence
of dilacerated
permanent tooth
Other possible
contributing factors
- scar formation
- developmental anomaly of the primary tooth
germ
- facial clefting
- advanced root canal infections
- ectopic development of the tooth germ and lack
of space
- the effect of anatomic structures
- the presence of an adjacent cyst tumor, or
odontogenic hamartoma,
- mechanical interference with eruption ,
- tooth transplantation,
- extraction of primary teeth, and
- hereditary factors

5. Primary dentition <<
Permanent dentition
- Maxillary >> mandibular
- Posteriors >> Anteriors
(Malcic A et al; 2006)
- Bilaterally occurring
dilacerations
- no sex predilection
Location of dilaceration Affected teeth
apical third of the roots Incisors, canines, and premolars
middle third of the root Molars
within the coronal third of the root Third molars
EPIDEMIOLOGY
Crown dilaceration

6. Difficult to differentiate:
- fused roots,
- condensing osteitis
- Crown : visual inspection
- Root : Radiographic examination
DIAGNOSIS
Mesial/ Distal dilaceration
Buccal/Lingual dilaceration
Panoramic radiography alone: not the method of choice for the diagnosis of
root dilacerations
Additional radiographs from different angles: recommended

7. ASSOCIATED SYNDROMES

8. TREATMENT CONSIDERATIONS
• In dilacerated teeth, the accepted basic endodontic techniques must be
strictly followed.
• Orthodontic movement of dilacerated teeth might cause severe
irreversible resorption of the root, which can severely complicate the
endodontic treatment of these teeth
 DIAGNOSIS

9. • In dilacerated roots:
 ACCESS CAVITY
• Direct access to the apical foramen, as much as possible,
is an important benefit gained through the access cavity
preparation
• Modification in access cavity:
Extending only that portion of the wall needed to free
the instrument, a cloverleaf appearance might evolve as
the outline form.
Luebke has termed this a “shamrock preparation”

10. • In dilacerated crown:
 ACCESS CAVITY
• Might require modification of the affected crown
• In severe cases, the affected part of the crown might
need to be removed, and a provisional prosthesis will
need to be placed until a definitive restoration is
possible

11. Bolhari B, Pirmoazen S, Taftian E, Dehghan S. A case report of dilacerated crown of a permanent mandibular central incisor. Journal of dentistry (Tehran, Iran). 2016 Nov;13(6):448.
11-year-old girl
Chief complaint: a swelling related to her
lower anterior teeth developed one month
ago
Dental history: a previous trauma (avulsion) to primary
mandibular anterior teeth (teeth #71, 81) when she was three
years old.
- Avulsed primary teeth had not been replanted.

12.  ROOT CANAL SYSTEM IDENTIFICATION AND PREPARATION
• Hybridization of techniques and file system: recommended “Scout files”
• Inability to continuously follow the root canal curvature
• “single use instruments”: recommended
• The use of copious irrigation, file recapitulation, and further irrigation should be
repeated more frequently in these severely curved canals

14.  ROOT CANAL SYSTEM IDENTIFICATION AND PREPARATION
• Multi-visit approach should also be followed
• Use of interappointment intracanal medicaments to increase the predictability of
the treatment.
• To overcome the complexity of reaching calcium hydroxide to the apical third of
dilacerated teeth:
calcium hydroxide with glycerin
Superior in regards to length of filling and density in
apical third of curved canals

15.  ROOT CANAL FILLINGS
• Lateral compaction of curved canals: might be difficult and sometimes
impossible in dilacerated canals
• If small, flexible spreaders cannot reach to within 1 mm of the working length:
dur to insufficient taper of root canal system; NiTi spreaders are recommended
• Warm or thermoplasticized gutta-percha techniques: more applicable

16.  INTENTIONAL REPLANTATION
• Not recommended: difficult extraction of curved roots
 ORTHODONTIC EXTRUSION
 PROSTHETIC TREATMENT
Root dilaceration concentrates the stresses in the supporting structures
if the dilacerated tooth is used as an abutment for a dental prosthesis, so
this should be considered as a risk factor in abutment selection

17. Byun C, Kim C, Cho S, Baek SH, Kim G, Kim SG, Kim SY. Endodontic treatment of an anomalous anterior tooth with the aid of a 3-dimensional printed
physical tooth model. Journal of endodontics. 2015 Jun 1;41(6):961-5.
Endodontic Treatment of an Anomalous Anterior Tooth with the Aid of a 3-dimensional
Printed Physical Tooth Model
RAPID PROTOTYPING
TECHNOLOGY
Medical history: showed that he had
cerebral meningitis at 4 months after birth
and cerebral subdural empyema at 6
months, which required head surgery
and long-term anticonvulsant medication
for 1 year

18. Byun C, Kim C, Cho S, Baek SH, Kim G, Kim SG, Kim SY. Endodontic treatment of an anomalous anterior tooth with the aid of a 3-dimensional printed
physical tooth model. Journal of endodontics. 2015 Jun 1;41(6):961-5.
Endodontic Treatment of an Anomalous Anterior Tooth with the Aid of a 3-dimensional
Printed Physical Tooth Model

19.  PROGNOSIS
• The prognosis of dilacerated teeth that require endodontic treatment varies
according to the severity of the deformity and the practitioner’s skills
• in many cases, the prognosis will not become evident until the practitioner has
undertaken initial endodontic treatment to determine whether the canal can be
negotiated completely and then adequately disinfected and filled

20. CONCLUSION
o Dilacerated teeth are not common, but they do pose a number of
diagnostic, management, and prognostic challenges to dental
practitioners.
o The presence of a dilaceration must be identified before treatment, and
this can be achieved by a thorough clinical and radiographic
examination. Once identified, the effect of the defect on the endodontic
and restorative dental management of the tooth can be more fully
assessed.

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28. THANK YOU!