Punch biopsy: on day eight, a standardized circular wound of 3.5 mm diameter and approximately 1.5 mm deep will be created in the mucosa of the hard palate with aid of a biopsy punch. The biopsy is performed under aseptic conditions and local anesthesia using lidocaine 2% combined with epinephrine for local hemostasis. A scalpel is used to remove the surface epithelium and underlying superficial connective tissue, which will be discarded according to biosafety regulations from the Institute of Dentistry, University of Copenhagen. After wounding, the wound site will be photographed (blind-coded) with an intraoral camera, placing a standard-sized 6 mm diameter template around the wound as reference. The participant will attend to the dental clinics on days two, five and eight post-wounding to have a photograph of the wound taken by Ph.D student Gina Castiblanco. The wound-size on photographs will be measured by two raters and will be expressed as the ratio of the wound surface area relative to the standard label size with aid of software (Canvas 7, ACD Systems of America). The endpoint will be the percentage of initial wound size, measured at days two, five and eight post-wounding.