Final answer:
Extreme resorption of an edentulous mandible can lower the alveolar ridge to the level of the mylohyoid muscle attachment, which is associated with the mylohyoid line on the inner aspect of the mandible. This has implications on the morphology of the mandible and functions such as speech.
Step-by-step explanation:
Extreme resorption of an edentulous mandible can bring the alveolar ridge to the level of the attachment of the mylohyoid muscle, which is linked with the mylohyoid line on the mandible. The alveolar process of the mandible serves to anchor the lower teeth, but when it is resorbed to a significant extent, this process can approach the level where the mylohyoid muscle, part of the floor of the oral cavity, attaches. This muscle assists in the movement of the tongue and the floor of the mouth during swallowing.
The anatomy of a tooth includes its securement in the alveolar process via the gingivae and the periodontal ligament. Factors like periodontal disease or osteoporosis can lead to resorption of the alveolar process. This resorption can result in a change of the mandible's morphology, influencing functions like speech and the fitting of dental prostheses.