Tooth Resorption Flashcards
Discuss tooth resorption?
Various types of tooth resorption have been described. Tooth resorption occurs
in many other animal species including humans and more than seven types of
tooth resorption have been described. In cats, this condition has previously
been called FORLs (Feline Odontoclastic Resorptive Lesions), but this term have
new officially been superseded by “tooth resorption” as it the condition is seen
in many species (cats, dogs, humans), not just cats.
What is Internal Resorption?
Internal tooth resorption occurs in the pulp canal and is usually associated with
pulpitis.
What is external tooth resorption?
External tooth resorption occurs at the outside surface of the tooth root and
therefore affects cementum initially and later on also dentine. There are different types and stages of tooth resorption, so it is very important to realise that
radiography is the only way to distinguish between the various types of tooth resorption. The supragingival, gross presentation of resorptive lesions are identical
and effective treatment plans can only be established based on a radiographic
diagnosis of the types of resorptions associated with the resorptive lesions. It is
generally accepted that supragingival lesions should be considered as painful.
What is type 1 tooth resorption?
This type of external tooth resorption is usually closely associated with inflammation of the periodontal tissues. Macroscopically this type of resorption can be
detected by using an explorer at the gingival margin. It is usually associated with
signs of gingivitis or periodontitis.
The radiographic signs associated with type I tooth resorption indicate a
periodontal ligament space that can be clearly distinguished along the entire
root surface. Radiographically these lesions are described as “apple core” like
destruction of cementum and dentine, usually at the neck of the tooth. It is important that teeth affected by Type 1 resorption, require complete extraction of
all the roots and root segments.
What is type 2 tooth resorption?
This type of resorption is also described as replacement resorption. It is impossible to distinguish the supragingival lesions from those associated with type I
resorption. Radiographic signs associated with type II resorption includes ankylosis. Fusion of the tooth to the surrounding alveolar bone is generally considered
as an early sign of this type of resorption. It is assumed that ankylosis will progress to more complete replacement of tooth hard tissue with bone. With limited association with inflammation humans affected by a similar condition report
that this is not painful while it develops below the alveolar margin. These lesions
should be considered painful as soon as they emerge at the neck of the tooth
though.
Once radiography has confirmed lesions to be type 2, it is acceptable to consider
crown amputation as an effective treatment. It is accepted that the resorption
process will continue and that all of the teeth will eventually be replaced by
bone. An incidental finding during radiographic examination of both dogs and
cats often indicates so-called ghost roots. Very often the gingiva overlying these
areas are completely healthy with no signs of inflammation.
The most likely explanation of this finding is that replacement resorption has
progressively weakened the tooth structure until it fractured. Once the fracture
occurred, healing of the gingiva eventually sealed off the exposed fragments.
What is type 3 root resorption?
Affected teeth will show radiographic evidence of type I resorption on one root
and type II resorption on others.
What are the stages of tooth resorption?
Stage 1:
Lesions only affect the cementum. These are microscopic lesions that cannot be identified on radiography.
Stage 2:
Lesions affect cementum and dentine but do not affect
the pulp canal.
Stage 3:
Lesions affect cementum, dentine and the pulp canal.
Stage 4 A:
Indicates advanced tooth resorption affecting cementum dentine and pulp crown and root equally.
Stage 4 B:
Indicates advanced tooth resorption affecting cementum dentine and pulp. Root affected more severely than the crown
Stage 4 C:
Indicates advanced tooth resorption affecting cementum dentin and pulp. Only root and crown remnants visible on radiographs.
Stage 5:
Remnants of dental hard tissue are visible only as irregular radiopacities, and gingival covering is complete.
Discuss tooth resorption in Dogs?
A Study by Peralta et.al. established that the classification of tooth resorption in
humans is more applicable to describe tooth resorption in dogs. In dogs, resorption lesions are most frequently external replacement and external inflammatory
resorption,
Tooth resorption was detected in 53.6% of dogs. Like in cats tooth resorption
was more frequent among older and large breed dogs.
List the types of resorption seen in dogs?
*External replacement resorption and
* External inflammatory resorption (58/224 [25.9%] dogs.
* External cervical root surface resorption was detected in 13 of 224 (5.8%)
dogs
* External surface resorption
* Internal inflammatory resorption and
* Internal surface resorption was detected but no Internal replacement resorption was detected
List the Treatment of Teeth with Tooth Resorption?
Supragingival resorptive lesions are considered painful and affected teeth should
be treated. Only based on radiographic evidence the decision to do crown amputation rather than extraction, can be made.
It is generally accepted that tooth resorption is a slow process and especially in
dogs, early signs of ankylosis and replacement resorption does not necessarily
indicate immediate treatment. Radiographic monitoring to establish the rate of
progress is advisable if treatment is postponed but also for cases that have
been treated by crown amputation and intentional retention of resolving root
segments.
