Keratinized mucosa belongs to the masticatory mucosa, while nonkeratinizing mucosa belongs to the lining mucosa. Dental implants may be installed in either of these mucosal types. For the long-standing stability of the peri-implant mucosal tissues it is debated whether a band of keratinized mucosa surrounding the implant is needed. Increasing evidence from recent well-designed clinical studies points to that necessity. Hence, it may be anticipated that in certain cases the band of keratinized mucosa needs to be widened to at least 2 mm. Schlagwörter: Keratinized mucosa, dental implant