The main question addressed by this review produced by Cochrane Oral Health was whether or not treatment for moderate to severe gum disease (periodontitis) also has an effect on the prevention or management of heart and blood vessel (cardiovascular) disease.
Gum disease (periodontitis) is a common chronic or persisting condition that can get worse over time. It involves inflammation of the gums, which surround and support the teeth, causing swollen and painful gums and in severe cases loss of the bone (alveolar) that supports the teeth.
Clinical investigations have shown that there might be a link or association between chronic, ongoing gum disease (periodontitis) and heart and blood vessel disease (cardiovascular disease). Some investigators believe that the treatment for gum disease, which gets rid of bacteria and infection and controls inflammation, might prevent the occurrence or recurrence of heart disease.
The evidence on which this review is based is from searches up to 27 August 2017. The included randomised controlled study involved 303 participants.
At present there is only one suitable study looking at this issue. The study had problems with its design. Based on this evidence it was not possible to determine whether or not treatment for gum (periodontal) disease has any effect on the occurrence or recurrence of heart disease in people with chronic gum disease.
Quality of the evidence
The quality of the evidence was very low as there was only one study with problems in its design and how the study was conducted.
We found very low quality evidence that was insufficient to support or refute whether periodontal therapy can prevent the recurrence of CVD in the long term in patients with chronic periodontitis. No evidence on primary prevention was found.
There is an association between chronic periodontitis and cardiovascular disease (CVD). However, it is not known whether periodontal therapy could prevent or manage CVD in patients with chronic periodontitis.
The objective of this systematic review was to investigate the effects of periodontal therapy in preventing the occurrence of, and management or recurrence of, CVD in patients with chronic periodontitis.
Cochrane Oral Health’s Information Specialist searched the following databases: Cochrane Oral Health’s Trials Register (to 31 August 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 7), MEDLINE Ovid (1946 to 31 August 2017), Embase Ovid (1980 to 31 August 2017) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL EBSCO) (1937 to 31 August 2017) . The US National Institutes of Health Trials Registry (ClinicalTrials.gov), the World Health Organization International Clinical Trials Registry Platform and Open Grey were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.
We also searched the Chinese BioMedical Literature Database (1978 to 27 August 2017), the China National Knowledge Infrastructure (1994 to 27 August 2017), the VIP database (1989 to 27 August 2017) and Sciencepaper Online (2003 to 27 August 2017).
Randomised controlled trials (RCTs) and quasi-RCTs were considered eligible. Studies were selected if they included patients with a diagnosis of chronic periodontitis and previous CVD (secondary prevention studies) or no CVD (primary prevention studies); patients in the intervention group received active periodontal therapy compared to maintenance therapy, no periodontal treatment or another kind of periodontal treatment in the control group.
Two review authors carried out the study identification, data extraction and risk of bias assessment independently and in duplicate. Any discrepancies between the two authors were resolved by discussion or with a third review author. A formal pilot-tested data extraction form was adopted for the data extraction, and the Cochrane tool for risk of bias assessment was used for the critical appraisal of the literature.
No studies were identified that assessed primary prevention of CVD in people with periodontitis. One study involving 303 participants with ≥ 50% blockage of one coronary artery or a coronary event within three years, but not the three months prior, was included. The study was at high risk of bias due to deviation from the protocol treatment allocation and lack of follow-up data. The trial compared scaling and root planing (SRP) with community care for a follow-up period of six to 25 months. No data on deaths (all-cause or CVD-related) were reported. There was insufficient evidence to determine the effect of SRP and community care in reducing the risk of CVD recurrence in patients with chronic periodontitis (risk ratio (RR) 0.72; 95% confidence interval (CI) 0.23 to 2.22; very low quality evidence). The effects of SRP compared with community care on high-sensitivity C-reactive protein (hs-CRP) (mean difference (MD) 0.62; -1.45 to 2.69), the number of patients with high hs-CRP (RR 0.77; 95% CI 0.32 to 1.85) and adverse events (RR 9.06; 95% CI 0.49 to 166.82) were also not statistically significant. The study did not assess modifiable cardiovascular risk factors, other blood test results, heart function parameters or revascularisation procedures.