Young Bui
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 OOT
FRACTURES occur in fewer than 8 percent of traumatic injuries to permanent
teeth. When they do occur, hemorrhage from the pulp and periodontal
ligament (PDL) flows into the fracture site and clots. The fractured
surfaces of dentin and cementum are gradually remodeled by surface resorption
and apposition of calcific tissue. Root fractures heal differently
depending on the degree of separation of the fragments, the severity of
injury, and the ability of the pulp to heal. the differences in healing
may take any of the following forms.
Calcific healing is a form of healing in
which a calcific callus is formed at the fracture site on the root surface
and inside the canal wall. This type of healing requires a wide canal
with the fragments in close apposition with little or no mobility.
The pulp will be vital and the tooth will have little or no mobility.
Connective tissue healing is a form of healing
in which a fibrous attachment similar to PDL develops between the fractured
fragments. This results when the fragments are separated farther
apart or because some mobility is present. The pulp will be vital
and the tooth will have little mobility. The connective tissue will
appear as a fracture line on the radiograph.
Combined bone and connective tissue healing
is healing in which new bone may grow between the fractured segments if
further separation occurs or there is mobility of the parts. The
fractured surfaces are lined with cementum with new PDL growing between
the tooth and the new bone. The pulp is vital.
Healing with nonunion and granulation tissue
formation is a form of healing that occurs when the pulp is injured
or infected and becomes necrotic due to narrow root-canal space, contamination
of the pulp by oral fluids, or severe dislocation of the fractured root.
The pulp tissue in the incisal segment undergoes necrosis and the apical
segment will remain vital. The tooth will be loose and sensitive
to percussion, and it may turn dark.
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| FIGURE 1: Different forms
of healing: A, Calcific callus; B, Connective tissue; C, Combination of
bone and connective tissue; D, Nonunion and granulation tissue formation |
With most root fracture maintaining vitality of the
pulp, the main goal of treatment is to enhance this healing process.
The clinician should try to reunite the fractured segments by calcific
callus formation because the tooth will be stronger than one without the
union of broken parts. The fracture should be reduced as soon as
possible and the broken tooth firmly immobilized by splinting or bonding
to adjacent teeth.
There are two types of root fracture:
-
fracture without communication with the oral cavity
-
fracture with oral communication
The noncommunicating fracture occurs in the apical or
middle third of the root. Perform a vitality test, check for color
change in the crown, and record the degree of mobility of each traumatized
tooth. If the pulp is vital, then immobilize the tooth by splinting
it to the adjacent teeth. A radiograph should be taken after repositioning
to confirm realignment. The length of time to leave the splint on
ranges from one week to three months or more, depending on the degree of
mobility and the location of the fracture. There is no need to splint
the tooth if the fracture is in the apical third with little displacement
or mobility. If the fracture is at the crest of the alveolar bone
with modest displacement and mobility, the splint will have to stay for
three months or more.
When the splint is removed, the clinical status
of the tooth must be determined. The degree of mobility, color of
the crown, and vitality of the pulp should be recorded. If the periodontal
attachment has failed to heal, the prognosis for healing decreases drastically.
If the tooth responds as normal to a pulp test with little or no mobility
and the patient is comfortable, then there is nothing more to do but follow
up in six months and a year after that. If mobility is present, the
splint must be reapplied and the occlusion adjusted. The tooth should
be splinted permanently to the adjacent teeth if mobility is present after
six months.
If the fracture of any part of the root is coronal
to the periodontal attachment, the prognosis for healing is poor.
There is periodontal breakdown along the fracture line with pulpal necrosis
from the bacterial contamination through the fracture. The most common
type of fracture is seen in the maxillary incisor with the fracture on
the labial surface 2-3 mm supragingival but tapering obliquely to 2-5 mm
subgingivally on the lingual. This type of fracture can occur with
premolar and molar cusps. The fractured part should be removed during
the emergency visit, and endodontic treatment should be done in one visit.
Once the emergency has been taken care of, plans must be made for restoring
the tooth.
September-October 2002
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FIGURE 2: Calcific callus
formation of the root in an extracted tooth.
FIGURE 3: Endodontic treatment
on the coronal segment of a tooth with a horizontal fracture.
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