Under general anesthesia, the patient underwent excision and peripheral ostectomy of all four cysts. Teeth # 4,11,17,18, 19, 30, 31, and 32 were extracted as the cystic lesion was adherent to and had eroded into the bifurcation areas of all the first and second molars. There were two discrete 5mm areas in the mandibular right where the cyst had eroded into the inferior alveolar canal exposing the nerve, but no areas of frank bony buccal or lingual perforation. The patient reported no paresthesia postoperatively.

Incisional Biopsy

Histological examination of specimens from the area of teeth #s 4, 11, 17/18 and 32 revealed that all of them were similar. They were all made up of cystic structures (Figure 3). All cystic structures were lined by keratinized stratified squamous epithelium and supported by connective tissue walls. The lining epithelium was uniformly thin, corrugated and covered by parakeratin. The basal cell layer was palisaded (Figure 4). The lumen of some of the cysts was filled with keratin (Figure 5). The connective tissue wall was lose and cellular in some areas and fibrotic in others.

Figure 3 Higher power (x100) H & E histology shows a cystic structure with lining epithelium and a supporting fibrous connective tissue wall. The lining epithelium is uniformly thin and is corrugated and keratinized with palisaded basal cell layer. Note layers of keratin associated with this cyst.

Figure 4 Low power (x200) H & E closer look histology shows a cystic structure with keratinized lining epithelium and palisaded basal cell layer. Note the layers of keratin fibers associated with this cyst.

Figure 5 Higher power (x200) H & E closer histology of the layers of keratin with focal areas of early calcification.