public void PreencherporReplace(string CaminhoDocMatriz)
    {
        //Objeto a ser usado nos parâmetros opcionais
        object missing = System.Reflection.Missing.Value;

        Word.Application oApp = new Word.Application();

        object template = CaminhoDocMatriz;

        Word.Document oDoc = oApp.Documents.Add(ref template, ref missing,
                                                ref missing, ref missing);

        //Troca o conteúdo de alguns tags
        Word.Range oRng = oDoc.Range(ref missing, ref missing);

        object FindText = "@var1";
        object ReplaceWith = "teste";
        object MatchWholeWord = true;
        object Forward = false;

        oRng.Find.Execute( ref FindText, ref missing, ref MatchWholeWord,
                           ref missing, ref missing, ref missing, ref Forward,
                           ref missing, ref missing, ref ReplaceWith, ref missing,
                           ref missing, ref missing, ref missing, ref missing);


        oApp.Visible = true;
    }