Inflammation in mouth, joints in rheumatoid arthritis

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At the 93rd General Session and Exhibition of the International Association for Dental Research, researcher Sheila Arvikar, Massachusetts General Hospital, Boston, USA, will present a study titled "Inflammation in the Mouth and Joints in Rheumatoid Arthritis." The IADR General Session is being held in conjunction with the 44th Annual Meeting of the American Association for Dental Research and the 39th Annual Meeting of the Canadian Association for Dental Research.

Periodontitis shares pathogenic mechanisms with rheumatoid arthritis (RA) and may trigger its onset. In this study, researchers performed joint and dental examinations, determined Porphyromonas gingivalis (P. gingivalis) antibodies, and examined inflammatory microenvironments in early and chronic RA patients.

Twenty-three RA patients, (15 new-onset disease, eight chronic) and 20 age/gender-matched healthy subjects (HS) without periodontitis/RA were enrolled in this study. Serum P. gingivalis IgG antibodies were measured by ELISA. Twenty inflammatory mediators were measured in serum, saliva, gingival crevicular fluid (GCF), and joint fluid by Luminex.

The 23 patients (87% female) received routine dental care, except for one; none currently smoked. Of the 23 RA patients, 10 had gingivitis and nine had periodontitis. RA patients exhibited increased pocket depth, clinical attachment loss, bleeding on probing and GCF volume compared with HS. Six of 23 patients had P. gingivalis antibodies, and all six had periodontitis.
RA patients showed a marked inflammatory profile in all microenvironments, including oral, despite routine dental care. P. gingivalis antibodies can be considered as biomarkers for rheumatologists in identifying those who may benefit from periodontal treatment.

Graphene: A new tool for fighting cavities and gum disease?

Dental diseases, which are caused by the overgrowth of certain bacteria in the mouth, are among the most common health problems in the world. Now scientists have discovered that a material called graphene oxide is effective at eliminating these bacteria, some of which have developed antibiotic resistance. They report the findings in the journal ACS Applied Materials & Interfaces.

Zisheng Tang and colleagues point out that dentists often prescribe traditional antibiotics to get rid of bacteria that cause tooth decay or gum disease. But with the rise in antibiotic resistance, new approaches are needed to address these problems, which can lead to tooth loss. Previous studies have demonstrated that graphene oxide -- carbon nanosheets studded with oxygen groups -- is a promising material in biomedical applications. It can inhibit the growth of some bacterial strains with minimal harm to mammalian cells. Tang's team wanted to see if the nanosheets would also stop the specific bacteria that cause dental diseases.

In the lab, the researchers tested the material against three different species of bacteria that are linked to tooth decay and gum disease. By destroying the bacterial cell walls and membranes, graphene oxide effectively slowed the growth of the pathogens. The researchers conclude that the nanosheets could have potential uses in dental care.