Discussion
Impaction of teeth is a common presentation that dentists and surgeons
routinely diagnose. Most commonly this involves mandibular third
permanent molars impacting against the adjacent second molar. When
partially erupted, this can lead to recurrent infections involving the
pericoronal space. Cyst development can also be a complication of
impaction, sometimes causing displacement of the tooth and adjacent
structures. Our case was particularly interesting, not only due to its
kissing molar formation, but because it was bilateral in nature.
Currently only nine other cases of bilateral kissing molars could be
found in the literature.
This case highlighted how there is no set protocol or guidelines in
place for the management of kissing molars. Some cases may present a
high risk of pathological fracture and inferior alveolar nerve injury.
In these cases, a cone beam CT can prove helpful to provide information
regarding the buccolingual positioning of the IAN, width of remaining
bone and therefore aid planning[5]. For our
patient, the risk of damage to bilateral inferior alveolar nerves was
increased due to their close proximity to the second molars. Therefore,
following discussion with the patient, it was decided that surgical
intervention was only to be carried out in the lower left quadrant where
the dentigerous cyst was more advanced and presented a higher risk of
infection due to its oral communication.
For some patients, orthodontic alignment of the impacted molars may be
possible so an orthodontic opinion should be sought where appropriate.
Alternatively, kissing molars can be monitored, but a discussion with
the patient regarding the risks of nearby root resorption and cyst
formation should be balanced against the risks of surgical intervention.
Some clinicians routinely prescribe post operative steroids following
surgical removal of kissing molars[2]. Improved
patient comfort, reduced swelling and trismus following third molar
removal and post operative steroid use has also been
reported[6].
There remains no concrete evidence regarding the aetiology of kissing
molars. It is theorised by some that an ectopic tooth bud is responsible
and that early cystic development around a molar can cause their crowns
to displace[7].
Mucopolysaccharidosis[8] and hyperplastic dental
follicles[9] has also been suggested.