This is the classic presentation of a missing mandibular first premolar in a two year old lab with an unerupted first premolar…or is it?
The first radiograph shows an unerupted right mandibular first premolar surrounded by an increased periodontal ligament space. Utilizing a flap for exposure, extraction of this tooth and debridement of the surrounding bone should prevent what could be a developing cyst from progressing.
An alternate view demonstrates a lucent halo with a sclerotic periphery surrounding the mesial root of the second premolar.
Surgical exposure revealed soft tissue lining an abnormal cavity in the bone expanding to the lingual side of the mesial root of second premolar.
Extraction of the second premolar was required to adequately expose the presumed cyst for complete removal. The apical and lingual extent of the bone destruction can be seen here. The middle mental foramen and neurovascular bundle can be seen dorsal to the defect.
Extraction of the teeth and removal of all cyst material should eliminate the chance of recurrence. Histopath is pending. Note: There was no communication with the cyst wall and the mandibular canal in this case.