Endoscopic sinus surgery for the odontogenic maxillary cysts.

OBJECTIVE: To evaluate the effectiveness and usefulness of transnasal endoscopic surgery for the treatment of odontogenic maxillary cysts. METHODS: Between February 2003 and February 2008, transnasal endoscopic surgery was performed under general anesthesia in 13 patients (male 6 and female 7, 19 to 75 years old) with odontogenic maxillary cysts that extended to the maxillary sinus. Ten patients had a radicular cyst and three patients had a dentigerous cyst. After the resection of anterior edge of the inferior turbinate, the lateral wall of the inferior nasal meatus was opened. Then, the cyst wall of the maxillary sinus was partially or completely removed under the endoscope. RESULTS: The cyst walls were completely removed in five often patients with a radicular cyst and in all three patients with a dentigerous cyst. Five patients with a radicular cyst received partial resection of the cyst wall. The affected teeth could be preserved in seven of ten patients with a radicular cyst and in one of three patients with a dentigerous cyst. There were no complications, and postoperative courses were uneventful. Follow-up period ranged from 11 to 72 months (mean 42 months), and no recurrence has been noted in any of the cases. CONCLUSIONS: Endoscopic transnasal surgery for the odontogenic maxillary cyst is less invasive than conventional dental approach, and most of the affected teeth can be preserved. This technique appears to be a simple and highly effective surgical treatment for the treatment of patients with odontogenic cysts that extend to the maxillary sinus.

Effects of transglottal pressure on fundamental frequency of phonation: study with a rubber model.

The fundamental frequency of phonation (F0) change per unit change in transglottal pressure (dF/dP) was studied at different extension lengths and masses of the vibrating part of a rubber model. The dF/dP was decreased when the vibrating part was extended, and also when the mass of the vibrating part was increased. In the former, the F0 was increased, and in the latter, the F0 was decreased. In humans, we have noticed that when the F0 was increased, the dF/dP first decreased and then increased, taking a V-shaped curve as a function of the F0. The present study reveals the mechanism underlying the V-shaped curve observed in humans.