The third group of dental resorptions are insidious in
nature and generally present complex therapeutic
challenges. In these cases, resorbing tissue invades the
hard tissues of the tooth in a destructive, and apparently
uncontrolled fashion, akin to the nature of some fibro-osseous
lesions such as fibrous dysplasia.
An important distinguishing factor for this third group of
resorptions is that, unlike the first two types of
resorption, simple elimination of the cause of the lesion
is ineffective in arresting their progress. Total removal
or inactivation of the resorptive tissue is essential if
recurrence (or concurrence) is to be avoided.
Concurrence indicates the incomplete removal of the
resorptive tissue at the time of treatment and recurrence
is the re-establishment of the resorptive process. The
reason for recurrence or concurrence is probably due to
the invasive nature of the resorptive tissue whereby
small infiltrative channels are created within the dentine
and these may interconnect with the periodontal
ligament in positions more apical to the main resorptive
defect.
Unless the tissue in these infiltrative channels is
inactivated the resorptive process will continue. While
these resorptions are not considered to be neoplastic,
their aggressive characteristics can seem to be similar.
At the present time one proven therapy for inactivation
is chemical in nature but surgical and other
technological modalities may also be applied.
These hyperplastic invasive resorptions may have a
pulpal (internal) or a periodontal origin (external).
Critical to the clinical use of therapies aimed at
controlling internal and external invasive tooth
resorptions is the correct diagnosis of the type and
localization of the resorption.
Hyperplastic resorptions may be subdivided into
internal replacement (invasive) resorption, invasive
coronal resorption, invasive cervical resorption and
invasive radicular resorption.