Yesterday is the 29 days after glottoplasty, I've been keeping my talk very minimum since the second week, but yesterday I tried to hold my sneeze but failed, so it's like an air explosion in my throat, so right after that incident no voice came out and when it did came out it sounded deep, I'm worry I break all the stitches, from the 2 weeks doctor visit, after sticking camera in my throat,  the Doctor told me the two vocal folds had been fused beautifully, so my question is " is there a chance for the two folds to unmerged with that big big sneeze", that sneeze really irritate my throat so might cause some damage

I can't say for sure, but at around 4-6 weeks dissolvable sutures normally would be finished doing their job and would dissolved. It's possible the sneeze might have cause the sutures to release a bit sooner. About the only way of knowing for sure if there is damage would be to wait a few days and see if things clear up or have another doctors visit to check things out.