A group of scientists from Tohoku University have discovered that gingiva stiffness influences the properties of gingival fibroblasts, which in turn affects whether inflammation is likely to occur and makes gingival fibres difficult to form.
Their findings were published in the journal Scientific Reports on January 24, 2023.
Associate Professor Masahiro Yamada from Tohoku University's Graduate School of Dentistry said, "We discovered that soft gingiva results in inflammation and hinders the development of gingival fibers."
It has long been known that individuals with thick or stiff gingiva are less susceptible to gingival recessions. This is where the gingiva begins to recede and expose a tooth's root. Many factors can lead to gingival recession, such as gum disease, over-brushing, and chewing tobacco. But, this is the first time gingival stiffness has been attributed to biological reactions.
Although fibroblasts play an important role in the maintenance, repair and healing of the gingiva, they also produce various inflammatory and tissue-degrading biomolecules which degrade the gingival fibres. In addition, fibroblasts are associated with immune responses to pathogens.
Masahiro, along with his colleague Professor Hiroshi Egusa, created an artificial culture environment that simulated soft or hard gingiva and cultured human gingival fibroblasts on them. They discovered that hard gingiva-simulated stiffness activated an intracellular anti-inflammatory system in the gingival fibroblasts that prevented inflammation. Yet, soft gingiva-simulated stiffness suppressed the fibroblastic anti-inflammatory system. This increased the likelihood of inflammation and resulted in less collagen synthesis.
Masahiro Yamada added, "Our research is the first to demonstrate the biological mechanisms at play in regards to a patient's gingival properties. The results are expected to accelerate the development of advanced biomaterials to control local inflammation or microdevices that simulate the microenvironment of inflammatory conditions."