5. Discussion
The radicular cyst in deciduous teeth is classified as an inflammatory
odontogenic cyst, typically resulting from dental pulp necrosis caused
by caries, trauma, abnormal tooth development, and other factors[1]. It can also arise from the use of materials
containing cresol in dental pulp treatment [6].
Radicular cysts in deciduous teeth can cause local pain and swelling, as
well as apical bone destruction. In severe cases, it may lead to
extensive bone destruction and affect the inherited permanent tooth
germ, resulting in impaction of the inherited permanent teeth. Small
radicular cysts in deciduous teeth often resolve spontaneously after
extraction of the affected deciduous teeth. For extensive radicular
cysts in deciduous teeth, permanent tooth germs should be preserved as
much as possible, because children have a strong bone regeneration
ability and can repair bone defects quickly after operation[3]. Therefore, for a large range of radicular
cysts in deciduous teeth, relatively conservative treatment schemes,
such as bagging or decompression and drainage, should be considered to
protect the permanent tooth germs under deciduous teeth as much as
possible[4].
Root dilaceration refers to abnormal tooth development in which the
crown or root deviates from the long axis of the tooth, often resulting
in a certain bending angle between the crown and root (or part of the
root), and this condition is considered an abnormality in tooth
morphology. Root dilaceration usually fails to erupt smoothly, resulting
in impaction. Impacted teeth with root dilaceration are usually caused
by acute mechanical injury [7] or developmental
interference factors, including apical periodontitis of deciduous teeth,
cleft lip, and palate, ectopic tooth germ development, soft tissue
scarring, insufficient space, or interference from surrounding
structures, dental tumor, dental follicles, adhesion of the deciduous
teeth root, genetic factors, and some syndromes[8]. This case demonstrates root dilaceration and
impaction of the inherited permanent teeth caused by a radicular cyst in
the deciduous teeth. It highlights the importance of maintaining the
health of deciduous teeth for the proper development and eruption of
permanent teeth. The prevention and treatment of children’s dental
diseases still needs continued efforts. For impacted teeth without root
dilaceration, early orthodontic traction can reduce the risk of
developing root dilaceration. For the affected teeth with root
dilaceration, early orthodontic traction can use the development
potential of the epithelial root sheath to produce a secondary
curvature, thereby promoting continued root development. It increases
the root length and reduces the crown-root angle[9-11]. At the same time, orthodontic traction can
prevent alveolar bone atrophy and adjacent tooth inclination after
missing teeth. Even if the tooth becomes loose over time due to
excessive chewing forces, it preserves sufficient alveolar bone mass for
adult implant restoration.
Therefore, early detection, diagnosis, and traction are needed for
impacted teeth with root dilaceration. Moreover, even for root
dilaceration with short roots or bone fenestration after traction, as
long as there is no significant abnormality in pulp vitality or abnormal
looseness, the long-term postoperative effect of traction treatment is
ideal. This may be attributed to the favorable physical chimerism
between the curved roots and the alveolar bone, allowing the crown to
withstand normal bite force [12, 13].