Oral opening - Oral cavity - Oral cavity - e-Anatomy
View the module

Oral opening

Rima oris

  • Synonym: Oral fissure
  • Related terms: Oral fissure; Oral opening

Definition

Muhammad A. Javaid

The oral opening or the oral fissure is the horizontal opening of the mouth formed between the upper and lower lips. It represents the external entrance to the oral cavity and extends laterally to the angles (corners) of the mouth, also known as the oral commissures.

Is this definition incorrect or incomplete?

References

  • Kamrani P, Sadiq NM. Anatomy, Head and Neck, Oral Cavity (Mouth) [Updated 2023 Aug 14]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan. Available from: https://www.ncbi.nlm.nih.gov/books/NBK545271/

Gallery