Sir,- A 14 year old male patient attended another surgery for care in March 1995. He had a retained LLC. An OPG showed LL3 erupting and an 11 mm diameter well defined circular radiolucency over the apex of LL4 mesial to and above the mental foramen (Fig. 1). I saw him for the first time in July 1997.

figure 1

Figure 1

The previous dentist supplied me with the original radiograph and a new radiograph (Fig. 2) showed that the lesion was now more irregular and much larger (3cm × 2.5 cm). The adjacent teeth had been visibly displaced by the growing lesion. LLC was still retained and LL3 had not apparently moved; however he was suffering pain consistent with an infection in the lower left quadrant.

figure 2

Figure 2

He was given penicillin and at a subsequent appointment the LLC was extracted. He was referred for a consultant's opinion with regard to the growing cyst-like lesion between LL4 and LL5. He failed to attend for care at the hospital.

However the consultant agreed that investigation was a good idea after seeing the radiographs. I next saw the patient in September 2003.

He was complaining of pain on his left side. A further OPG was taken to assess the state of the lesion (Fig. 3). The lesion had spontaneously resolved and the premolars had moved back together.

figure 3

Figure 3

His pain was from the UL7 which was grossly carious. Perhaps the removal of LLC and subsequent eruption of LL3 allowed the cyst to exteriorise.

Comments?