“…These alterations plus missing teeth lead to decreased or increased VDO, which is visualized by changes in the distance between the nasal spine (Subnasale, "Sn") and the most anterior inferior point of the chin (Soft Tissue Menton, "Me"). When the mandible is in physiologic rest position with non-contacting teeth, it is called rest vertical dimension (RVD), which differs from VDO [15][16][17] . Many methods have been suggested over the past decades to establish VDO: swallowing, phonetic, rest position, maximum closing force, pre-extraction records, Willis, Landa, McGee, Hayakawa, comfort, cephalometric, anthropometric and Knebelman's craniometric method, but none of them can register VDO objectively.…”