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This issue features articles on long COVID, methoxyflurane, and functional neurologic disorder.
Cover image: Dental enamel SEM. Tooth enamel, the compact white substance protecting the dentin, is the hardest substance in the human body. Microscopically, the prismatic structure of enamel gives the crown of the tooth a spiral-like surface. Despite its strength, tooth enamel can be destroyed by acids which bacteria produce from sugar.