A 56-year-old man (smoker) has pain at #2 (Fig.1-3 thickened sinus membrane (R>L), C: mucous retention cyst) associated with subgingival crack (Fig.4 arrowheads).  缺失两个磨牙，造成剩余磨牙折裂，右上七。五十六岁男抽烟右上七折裂疼痛，右侧上颌窦可能粘液囊肿（图一C）。

Sinus Cyst     Last     Next  Xin Wei, DDS, PhD, MS 1st edition 07/15/2020, last revision 08/09/2020

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