How do I move data from Custom Task Pane in active word document

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C#

MS-Word

OpenXML

Dear Sir,
I am developing a word addin for MS Word 2013. In this when the user open a new word document file and click on the addin, the custom task pane will get filled with the attributes of the table from the database in multi check box. After selecting the desired attributes, when user click on the insert button on that task pane, the selected attributes will move to the active word document. Then we can save that file. I am using open xml sdk 2.5 and ms word 2013.
My problem is that I am not able to move the content from the custom task pane to the word file. Please guide me how will I do that.