[Sparing normal oral tissues with individual dental stent in radiotherapy for primary nasopharyngeal carcinoma patients].

Background & Objective: With the progression of radiotherapy techniques, the 5-year overall survival rate of nasopharyngeal carcinoma (NPC) patients has increased obviously. As the survival time prolonged, more and more attention was paid to various radiation sequelae and the quality of life of the patients. This study was to explore the role of individual dental stent in sparing normal oral tissues for primary NPC patients in radiotherapy by pushing the tongue and a part of oral mucous membrane away from the radiation fields.

Methods: Irradiation dose and volume of the tongue of a NPC patient before and after wearing dental stent was evaluated. A total of 43 patients were randomized into 2 groups: 19 in trial group and 24 in control group. Trial group wore dental stent during radiotherapy, while control group did not. Patients' weight, taste, oral mucous reaction, and tongue mucous reaction before radiotherapy and every week during radiotherapy were examined.

Results: Dosimetric analysis proved that the irradiation dose and volume of the tongue decreased obviously in trial group. The occurrence rate of grade 1-2 mucositis of the oral cavity was higher in trial group than in control group (73.68% vs. 62.50%), but the occurrence rate of grade 3-4 mucositis was lower in trial group than in control group (26.32% vs. 37.50%, P=0.470). By the completion of radiotherapy, 4 (21.05%) patients in trial group and 19 (79.17%) in control group suffered from taste dysfunction (P<0.001).

Conclusion: Individual dental stent is useful in sparing the oral mucous membrane and preserving taste for primary NPC patients in radiotherapy.