Share Hub

Diabetes and Dental Implants

From the pre-surgical decision to long-term maintenance.

The common question is whether an implant can be placed in a diabetic patient. The answer is yes. But this is not really one question, it is two, and they are usually confused with each other. First, whether the implant reaches osseointegration or not. Second, how many years it stays in the patient's mouth. The answers to these two are different.

∆ 1. Controlled diabetes is not a contraindication to implants

Diabetes today is a risk factor, not a contraindication. The threshold for adequate control is an HbA1c below 7 percent. Up to below 8 percent is usually still considered acceptable.

Within this range, implant survival has no practical difference from non-diabetic patients. The reported figures are around 96 to 97 percent at one year and around 87 to 96 percent at five years. In comparative studies, the failure rate during the osseointegration phase has also shown no significant difference from the healthy group.

So a patient with a controlled three-month glucose value is a suitable candidate.

∆ 2. The patient with uncontrolled glycaemia

This is where it is easy to draw the wrong conclusion.

Studies that measured implant stability during the first weeks have seen a larger and longer dip in patients with poor control. Even so, those same implants eventually reached stability, and after one year no appreciable difference remained.

One meta-analysis also compared the failure rate directly between controlled and uncontrolled diabetes and found no significant difference. But this is a single study, not a consensus. The number of patients and implants examined was small, and its result is more of the kind "no difference was shown" than "there is no difference". These two sentences are not the same.

Another point is that the patients in these studies were usually people whose glucose alone was high, not patients with advanced systemic complications. So generalising the result to every diabetic patient is not correct.

The reasonable practical position is this. Do not treat uncontrolled glycaemia as an absolute contraindication, but do not count it as a licence either. If surgery can be postponed until glycaemic control improves, that is worth doing. If it cannot, proceed with a more conservative protocol.

One specific recommendation appears in the sources: immediate loading should not be performed in the diabetic patient.

∆ 3. After osseointegration, the concern changes

Up until osseointegration your concern is early failure. After that, the concern shifts to peri-implantitis and crestal bone loss. That is, from an event that is over within a few weeks, we move to a chronic situation that continues for the rest of the implant's life. Here glycaemic control is no longer a condition for getting through surgery, it is a permanent factor.

The most important clinical finding in this part is this. The risk of peri-implantitis in the diabetic patient is around 50 percent higher, but the risk of mucositis is not significantly different.

In other words, the difference diabetes makes is not in whether the inflammation starts, it is in what becomes of it. The same mucositis that in a healthy patient usually resolves with a single debridement session and improved hygiene is more likely, in the diabetic patient, to end in bone destruction. For the practice, that means lowering your threshold for intervention in these patients.

As for whether a higher HbA1c means a worse peri-implant condition, the evidence is not uniform. Some sources have reported a dose-dependent relationship. Others have not found such an association among diabetic patients themselves, provided that oral hygiene is carefully maintained. What is repeated more consistently across the different sources is the difference between diabetic and non-diabetic patients, not the difference between varying degrees of hyperglycaemia.

∆ 4. You do not see the effect of diabetes in the first years

Up to roughly the first six years, implant survival in diabetic and non-diabetic patients is no different. The difference shows itself in longer follow-up. The same pattern is seen with peri-implantitis. In the early years there is no appreciable difference, but in the long term peri-implant inflammation is more common.

The practical conclusion is clear. Do not take success in the first two or three years as a sign that you can relax. It is precisely this early success that causes recall to slacken.

∆ 5. The follow-up interval

There is no dedicated, established figure for the diabetic patient. What the sources do offer is this:

For a patient at moderate risk, an interval of 5 to 6 months is recommended — and that as a maximum, not a minimum.
For the first year after implant placement, a three-month interval has been suggested.
The diabetic patient falls into the high-risk category because of the higher peri-implantitis risk, so a shorter interval is logical for them.

Note that no study has measured the recall interval specifically in diabetic patients. Shortening the interval in these patients comes from the logic of their higher risk, not from a figure obtained in a study. In practice, three to four months is a reasonable choice, especially in a patient who also has a history of periodontitis or smoking.

∆ 6. What is still unclear

Scientific fairness requires saying this too. Most of the studies that have shown an association between diabetes and peri-implantitis are retrospective or cross-sectional in design. That means causation cannot be concluded from them and they should be read as association only. The data on osseointegration in controlled diabetes are also still described as heterogeneous.

Even so, the shared conclusion across the sources is clear. Diabetes should be regarded as a potential risk factor for delayed osseointegration, peri-implant inflammation and lower survival, and it should be accounted for in the treatment and follow-up plan.

∆ 7. The summary for the practice

Order an HbA1c, not just an FBS. Below 7 is ideal, up to 8 acceptable with caution.
Do not use immediate loading, and allow a more generous healing period.
Explain to the patient that glycaemic control is not a permit to get through surgery, it is the condition for the implant lasting.
Shorten the recall interval and treat every mucositis earlier and more seriously.
Spend time on oral hygiene. In these patients, good hygiene compensates for much of the difference.
Diabetes plus a history of periodontitis or smoking means accumulated risk. The maintenance programme must be correspondingly stricter.