Retromylohyoid curtain forms the distal end of the alveolingual sulcus. It is a curtain formed by the mucous membrane in the oral cavity. Retromylohyoid curtain bounds the Retromylohyoid fossa.
Location: Retromylohyoid curtain is situated between the anterior pillar of fauces and pterygomandibular fold
The muscles which form the retromylohyoid curtain are:
- Posterio laterally: Superior constrictor muscle
- Posterio medially: Palatoglossus muscle and lateral surface of tongue
- Inferiorly: Mylohyoid muscle and Submandibular gland
Importance of Retromylohyoid curtain in prosthodontics:
- It acts as a limiting structure in forming the lingual flange of mandibular denture.
- It is pulled forward when the tongue is protruded out making it an important landmark to be considered while fabricating the mandibular complete denture.
- Distolingual portion of the flange is influenced by glossopalatine and superior constrictor muscles which constitute the Retromylohyoid curtain.
- The action of the medial pterygoid muscle helps in deciding the posterior border of the denture near the retromylohyoid fossa
- Retromylohyoid fossa is bounded by the retromylohyoid curtain
- The posterior border of the denture should touch the retromylohyoid curtain when the tip of the tongue is placed against the central part of the residual alveolar ridge.
- Contraction of the medial pterygoid muscle causes a bulge in the Retromylohyoid curtain as it medial pterygoid lied behind the superior constrictor