Complete Dentures: Indications and Function

Study Notes

Angle of mouth: Dentures should be made to support the mouth angle and prevent angular cheilitis, a disorder caused by continuous wetting of the mouth angle by saliva.
Modiolus: A meeting point of facial muscles near the mouth angle. With teeth loss, the modiolus is displaced, leading to sunken cheeks and the need for a thin denture at the premolar region to prevent lifting.
Nose: The ala of the nose and the tragus of the ear form the imaginary ala tragus line.
Intraoral Landmarks: The oral cavity is divided into the vestibule and oral cavity proper, with the labial and buccal vestibules. After tooth extraction, the alveolar bone is resorbed, leaving the residual ridge.
Maxillary Anatomical Landmarks: The alveolar ridge, the highest part of the maxillary residual ridge, is considered the primary stress bearing area. The maxillary tuberosity, a rounded prominence, should be included in the impression.
Palatal Landmarks: The palatine vault, the median palatine raphe, the incisive papilla, and the torus palatinus are important landmarks for upper denture fabrication.
Mandibular Anatomical Landmarks: The alveolar ridge, the retromolar pad, the external oblique ridge, and the mental foramen are essential for lower denture design.
Stress Bearing Areas and Relief Areas: Primary stress bearing areas, such as the crest of the ridge, the buccal shelf area, and the flat areas of the palate, are critical for withstanding the forces of occlusion.
Border Structures: Structures that limit the periphery of the denture, including the labial frenulum, labial vestibule, buccal frenulum, and buccal vestibule, must be considered when designing dentures.
Tooth Extraction: The alveolar bone is resorbed after tooth extraction, leaving the residual ridge. The size of the maxillary tuberosity is affected by the extension of the maxillary sinus. Specific landmarks, such as the palatine vault and torus palatinus, need to be considered when fabricating dentures.
Denture Foundation: The denture foundation is the surface on which the dental prosthesis rests. The amount of force applied is inversely proportional to the surface area covered.
Relief Areas: Relief areas are portions of the denture that are reduced to eliminate excessive pressure on the supporting tissue. Key areas include the incisive papilla, median raphe, torus palatinus, sharp bony prominances, and the mental foramen.
Genial Tubercles: Two small prominences on the inner surface of the mandible, located at the symphisis, are essential landmarks for lower denture fabrication. In extreme bone resorption, the denture should be relieved in this area.
Occlusal Plane: The occlusal plane of the mandibular denture must not be higher than half of its vertical height and must be covered by the denture to prevent movement. The denture should not extend beyond the external oblique ridge to avoid displacement.
Mylohyoid Ridge: The lower denture should be relieved in the area of the sharp mylohyoid ridge for patient comfort.
Cannot forget surgical correction for extremely large tuberosities, sharp bony prominences, or unilateral/bilateral torus mandibularis, or excessive bone resorption at the genial tubercles.