Treating gum disease: can it help diabetics control their blood sugar levels?

iStock_000013589042_SmallGum disease treatment is used to reduce swelling and infection from gum disease. Keeping blood sugar levels under control is a key issue for people with diabetes, and some clinical research suggests a relationship exists between gum disease treatment and glycaemic control. As a result, it is important to discover if gum disease treatment does improve glycaemic control to encourage better use of clinical resources.

There is a broad range of gum disease treatments available for treating patients with diabetes. This review considered:

1. Does gum disease treatment improve blood sugar control in people with diabetes?
2. Does one type of gum disease treatment have a bigger effect than another in improving blood sugar control?

What was the research?

A systematic review of the evidence to find out the effectiveness of gum disease treatment for controlling blood sugar levels (known as glycaemic control) in people with diabetes, compared to no active treatment or usual care.

Who conducted the research?

The research was conducted by a team led by Terry C. Simpson from the Edinburgh Dental Institute, on behalf of the Cochrane Oral Health Group. Jo C. Weldon, Helen V. Worthington, Ian Needleman, Sarah H. Wild, David R. Moles, Brian Stevenson, Susan Furness and Zipporah Iheozor-Ejiofor were also on the team.

What evidence was included in the review?

Data was extracted from 35 randomised controlled trials. A total of 2,565 people participated in the trials, and were randomly assigned to receive a type of gum disease treatment. This included scaling and root planing (SRP) and SRP combined with other types of treatment, or usual care/no active treatment. The trials included in this review used SRP with, or without, an additional treatment. Additional treatments included instructions for cleaning teeth properly (known as oral hygiene instruction or OHI), and other gum treatments (for example, antimicrobials, which are used to treat infections).

What did the evidence say?

The evidence from 14 trials (1499 participants) showed that SRP reduces blood sugar levels in diabetic patients by 0.29% up to 4 months after receiving care when compared with usual care/no active treatment. After 6 months, there was no evidence that this reduction was sustained. Evidence from 21 trials (920 participants) investigating different types of gum disease treatments failed to show that one treatment was better than another. There were not enough studies measuring side effects to be able to show if gum disease treatments cause any harm.

How good was the evidence?

There is low quality evidence to support using scaling and root planing for controlling blood sugar levels up to 4 months after receiving treatment. Ongoing gum disease treatment is advised to maintain improvements in blood sugar levels.

What are the implications for dentists and the general public?

There is low quality evidence that the treatment of periodontal disease by scaling and root planing does improve glycaemic control in people with diabetes, however, there is insufficient evidence to demonstrate that this is maintained after 4 months. There was no evidence to support that one periodontal therapy was more effective than another in improving glycaemic control in people with diabetes. In clinical practice, ongoing professional periodontal treatment will be required to maintain clinical improvements beyond 6 months.

What should researchers look at in the future?

Further research is required to determine whether adjunctive drug therapies should be used with periodontal treatment. Future randomised controlled trials should evaluate this, provide longer follow-up periods, and consider the inclusion of a third ‘no treatment’ control arm. Larger, well conducted and clearly reported studies are needed in order to understand the potential of periodontal treatment to improve glycaemic control among people with diabetes. In addition, it will be important in future studies that the intervention is effective in reducing periodontal inflammation and maintaining it at lowered levels throughout the period of observation.


Simpson TC, Weldon JC, Worthington HV, Needleman I, Wild SH, Moles DR, Stevenson B, Furness S, Iheozor-Ejiofor Z. Treatment of periodontal disease for glycaemic control in people with diabetes mellitus. Cochrane Database of Systematic Reviews 2015, Issue 11. Art. No.: CD004714. DOI: 10.1002/14651858.CD004714.pub3.