Embrasures Definition: Two teeth in the same arch are in contact, their curvatures adjacent to the contact areas form Spillway spaces called Embrasures.
A Gap between 2 adjacent teeth, as the teeth curve away from the contact area.
Types of Embrasures:
- Labial (or) Buccal and Lingual Embrasures: The spaces that widen out from the area of contact labially or buccally and lingually. These Embrasures are continuous with the interproximal spaces between the teeth.
- Incisal (or) Occlusal Embrasure: The Spaces above the Occlusal and incisal contact areas which are bounded by the marginal ridges as they join the cusps and incisal ridges. These ridges are continous with the Labial (or) Buccal and Lingual Embrasures.
Functions Of Embrasures:
- Provides a Spillway for Food during mastication – This reduces the forces briught to bear on the teeth during the reduction of any material that offers resistance.
- Prevents Food from being forced through the contact area, when teeth wear down to the contact area so that no embrasure remains, seen mostly in the incissors, where food is pushed into the contact area even when teeth are not mobile.
- Makes Teeth more Self Cleansing.
Notes on Embrasures based on Teeth:
- Maxillary Anteriors: The Lingual Embrasures are always greater than the Facial Embrasures.
- Mandibular Anteriors: The Facial Embrasures are greater than the Lingual Embrasures
- Posteriors: Lingual Embrasure is greater than the Facial (Except in Maxillary Molars)
- Maxillary Molars: The Facial Embrasure is Greater than the Lingual Embrasure. Embrasures between 2 molars are the smallest embrasures in the oral cavity.
- The incisal/Occlusal Embrasure is always smaller than the Gingival Embrasure