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Custom-made lip bumper to protect the maxilla from irradiation. (A) Mouthpiece with lip bumper from the lingual side (arrow). (B) Mouthpiece with lip bumper from the palatal side (arrow). (C) Bumped lip position with custom-made mouthpiece. (D) T1-weighted contrast-enhanced axial magnetic resonance image of lip tumor with lip bumper.
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Therefore, a bumper moves the lip anteriorly to protect the maxilla from irradiation (Fig. 1A, 1B). For the lip bumper in this case, the EVA base occupied the entire oral vestibule, excluding the superior labial frenulum (Fig. 1C, 1D).
Dose distribution in the maxilla. (A) Actual clinical results of dose distribution with the mouthpiece. (B) Clinical results of dose distribution without the mouthpiece in a simulated treatment. (C) Dose-volume histogram for maxilla with and without the mouthpiece. Contours in red (gross tumor volume) and yellow (planning target volume).
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The dose distribution and port angles are shown in Fig. 2A. Two ports were used, and scanning CIRT was employed. Pretreatment diagnostic CT images in the same case were used to simulate treatment without a mouthpiece (Fig. 2B).