Dental implant stitches coming out could be a complication or it could also be a normal part of the healing process. If it is the former, you will need to return to your dentist to have it treated. If it is the latter, you may be able to just leave the falling out sutures as is.
Factors which determine if it is a complication:
Are the stitches dissolvable or non-dissolvable?
How long have the implant sutures been in your mouth?
Was a bone graft done in conjunction with implant placement?
The combination of all three of these factors will determine what course of action you need to take for these stitches that are about to come out.
Stitches dissolvability
Dissolvable stitches are supposed to come out on their own while non-dissolvable stitches remain until they're removed. So, are the dental implant stitches in your mouth that are coming out absorbable or non-absorbable?
What to do:
If they can dissolve then they're following their normal course of healing and no action is required on your end.
If they don't dissolve then you may have a complication which you will need to see your dentist for a follow up.
Causes for non-absorbable sutures to come out:
Suture rejection. Your body can sometimes reject stitches by pushing them out of your body while it's healing. This condition is often referred to as a spitting suture.
Knot loosened. If the surgical knot wasn't tied securely enough, it can loosen over time and begin to unravel while you're eating. That may eventually cause them to come out.
How to tell if they can dissolve
Your dentist should've told you if your dental implant sutures can dissolve or not but if you forgot, you can always give them a call. Alternatively, you can try to figure out their dissolvability by seeing what color they are.
Identifying them by color could be used as a rough approximation for what they could be. Although you do need to be careful because white and green stitches can be both absorbable and non-absorbable.
How long sutures stayed in
The non-dissolvable sutures should stay in the mouth indefinitely until your doctor removes them. The dissolvable ones will often last about 10-14 days before they fall out on their own.
When it's a complication:
If a non-absorbable stitch falls out or gets rejected.
If your self-dissolving suture comes out in less than a week.
Essentially, if they're coming out sooner than intended, you may need to have your dentist put them back in. Your dentist needs them to stay in your mouth for a certain period of time so that the dental implant can heal properly.
What they look like when they're coming out
Here are some demonstrative images of stitches and how they look when they're coming loose.
You can compare those photos to a securely tied stitch below.
Presence of bone graft
If you had a bone graft when you had your dental implant placed, your stitches should've been non-dissolvable which means it shouldn't be coming out. Therefore, if this is your situation you've a complication and you'll need to see your dentist to have the suture replaced.
Reasons stitches for implants with bone grafts shouldn't come out:
Bone grafts take weeks for it to heal so a dissolvable suture would be inappropriate.
Most dentists will place a membrane in addition to non-absorbable stitches.
In summary, the healing time that is required for an implant with a bone graft necessitates the use of a non-dissolving suture. If a dissolving one was used, it may get absorbed by the body before the graft is finished healing. That would jeopardize the bone graft.
The Verdict
Dental implant stitches that are coming out could be a normal part of the process if the stitches are dissolvable. Those are meant to stay in the mouth for 10-14 days before they fall out on their own. Although if they come out well before then, it may not be normal.
On the other hand, if the implant sutures are non-absorbable, there is a good chance you've a complication. These aren't meant to come out because they're supposed to be removed by your dentist.
