I did a GBR for a patient 1 month ago site 11,21,22. Everything healed very nicely. This same patient presented yesterday with a pea sized lump in the vestibule at the level of the 12 apex which also approximates the junction of the apical portion of the vertical release incision.It developed very recently and is painful and firm to palpate. I thought it was likely from a necrotic 12 however that tooth tested vital. I have done a number of these graft and have not encountered this before. Any feedback would be appreciated. Thanks.