The most serious form of trauma induced non-infective
root resorption is replacement resorption
which, as the name suggests, involves the progressive
replacement of tooth structure by alveolar bone and
ultimately tooth loss. Replacement resorption follows
the death of viable periodontal ligament cells due to
factors such as compression or drying of the ligament
cells as in the case of delayed replantation of an avulsed
tooth. On rare occasions an intact cementum/
cementoid layer may act as a biological barrier, so that
ankylosis (i.e., union with bone) is not accompanied by
replacement resorption. However, the usual response is
that of ankylosis with replacement resorption due to
the development, subsequent to surface resorption, of
an interface between bone and dentine with remodelling
processes occurring as part of normal skeletal bone
turn-over, but at the expense of dentine. There is total
loss of mobility due to this union of tooth and bone,
and the tooth gives a characteristically high percussion
sound but otherwise patients with replacement
resorption are symptom-free. Radiographically there will
be total loss of the image of the periodontal ligament
followed by evidence of the progressive replacement of
tooth structure by bone – in time the image of the tooth
root is lost. An example of an ankylosed tooth which is
undergoing replacement resorption is shown in Fig 8.
At present, there is no treatment possible for this type
of resorption and so the clinical management from the
initiation of replacement resorption to the inevitable
demise of the tooth poses important challenges
particularly in the developing dentition.If a tooth is in a satisfactory position in a mature
dentition, there is no urgency for tooth replacement as
often the replacement resorption proceeds at a slow
rate – in some instances taking many years to reach a
stage where carefully planned intervention is necessary.
This provides valuable time for both the clinician to
plan elective treatment, ideally in the form of implant
therapy, and for the patient to prepare himself/herself
both mentally and financially for that procedure. An
example of a tooth which has been undergoing replace-ment
resorption at a slow rate is shown in Fig 9. In this
instance, endodontic therapy had been carried out 13years earlier to reduce the possibility of superimposed
infection, but such endodontic intervention has no
effect on the progression of replacement resorption.
This procedure can be supplemented with the
application of Emdogain (Biora AB Malmo, Sweden) to
the affected root area in an attempt to repopulate the
denuded surface with cementoblasts. A successful
example of this form of management, with a long-term
follow-up, is shown in Fig 10. Even if re-ankylosis and
replacement resorption continue, the damage to arch
development can often be avoided or minimized.
In cases of ankylosis with advanced replacement
resorption a decoronation and submergence procedure
is recommended.
This allows ongoing alveolar growth
both vertically and axially, and it facilitates the
uncomplicated transition to implant therapy when
appropriate. An example of this approach is shown in
Fig 11.
root resorption is replacement resorption
which, as the name suggests, involves the progressive
replacement of tooth structure by alveolar bone and
ultimately tooth loss. Replacement resorption follows
the death of viable periodontal ligament cells due to
factors such as compression or drying of the ligament
cells as in the case of delayed replantation of an avulsed
tooth. On rare occasions an intact cementum/
cementoid layer may act as a biological barrier, so that
ankylosis (i.e., union with bone) is not accompanied by
replacement resorption. However, the usual response is
that of ankylosis with replacement resorption due to
the development, subsequent to surface resorption, of
an interface between bone and dentine with remodelling
processes occurring as part of normal skeletal bone
turn-over, but at the expense of dentine. There is total
loss of mobility due to this union of tooth and bone,
and the tooth gives a characteristically high percussion
sound but otherwise patients with replacement
resorption are symptom-free. Radiographically there will
be total loss of the image of the periodontal ligament
followed by evidence of the progressive replacement of
tooth structure by bone – in time the image of the tooth
root is lost. An example of an ankylosed tooth which is
At present, there is no treatment possible for this type
of resorption and so the clinical management from the
initiation of replacement resorption to the inevitable
demise of the tooth poses important challenges
particularly in the developing dentition.If a tooth is in a satisfactory position in a mature
dentition, there is no urgency for tooth replacement as
often the replacement resorption proceeds at a slow
rate – in some instances taking many years to reach a
stage where carefully planned intervention is necessary.
This provides valuable time for both the clinician to
plan elective treatment, ideally in the form of implant
therapy, and for the patient to prepare himself/herself
both mentally and financially for that procedure. An
example of a tooth which has been undergoing replace-ment
resorption at a slow rate is shown in Fig 9. In this
infection, but such endodontic intervention has no
effect on the progression of replacement resorption.This procedure can be supplemented with the
application of Emdogain (Biora AB Malmo, Sweden) to
the affected root area in an attempt to repopulate the
denuded surface with cementoblasts. A successful
example of this form of management, with a long-term
follow-up, is shown in Fig 10. Even if re-ankylosis and
replacement resorption continue, the damage to arch
development can often be avoided or minimized.
In cases of ankylosis with advanced replacement
resorption a decoronation and submergence procedure
is recommended.
This allows ongoing alveolar growth
both vertically and axially, and it facilitates the
uncomplicated transition to implant therapy when
appropriate. An example of this approach is shown in