On the other hand, a hard-bristled brush, coupled with vigorous brushing can result in recession of the gums and the abrasion of tooth enamel and exposed root surfaces.

另一方面，硬毛牙刷刷，刷的积极可能导致经济衰退的牙龈和牙齿的珐琅质磨损，暴露根耦合表面。

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In the most serious cases the enamel is worn away to such an extent that the dentine (the substance that comprises the bulk of the tooth) or even the pulp (the root) of the tooth are exposed.

BBC: NEWS | Health | Bad teeth blamed on fizzy drinks