Category: A

  • Apex

    Anatomic end of a tooth root or rootform implant. The terminal point of a body. The growing up of a shoot, or the very end of a leaf, which may take a variety of shapes. In dentistry, the end of a root of a tooth. The growing tip of a shoot; the uppermost part of…

  • Aperture

    An opening or orifice. In pollen, any absence of part of the exine. A hole drilled in a corneal contact lens in order to facilitate the exchange of gases underneath the lens. Entrance to a body cavity or channel. An orifice or opening, especially to anatomical or bony spaces or canals.  

  • Apertognathia

    An occlusal relationship where opposing teeth are not in contact (i.e., an anterior open bite).  

  • Apatite

    Calcium phosphate of the composition Ca5(PO4)3OH; one of the mineral constituents of teeth and bones (with CaCO3). A mineral containing calcium and phosphate ions and a univalent anion in a specific ratio; the major constituent of teeth and bones.  

  • Antrum

    Based on Greek antron meaning “cave,” a cavity or chamber in the body, often within bone. Any cavity inside the body, especially one in bone. Section of the stomach that terminates at the pylorus. A cavity, especially a cavity in a bone. The mastoid (or tympanic) antrum is the space connecting the air cells of…

  • Antrostomy

    The surgical opening of an antrum for purposes of drainage or grafting. A surgical operation to make an opening in the maxillary sinus to drain an antrum. A surgical operation to produce a permanent or semipermanent artificial opening to an antrum in a bone, so providing drainage for any fluid. The operation is sometimes carried…

  • Antroscopy

    Inspection of an antrum using an antroscope.  

  • Antroscope

    An instrument for illuminating and examining the maxillary sinus. An endoscope that can be introduced into the stomach via the esophagus to obtain a view of the pyloric antrum, the region of the stomach wall near the pyloric sphincter. An instrument for visual examination of a cavity, especially the maxillary sinus.  

  • Antrolith

    Calcified mass found in the maxillary sinus, resulting from the complete or partial encrustation of a foreign body (e.g., retained root).  

  • Antral polyp

    Multilocular, pendulous, irregularly shaped edematous space usually associated with rhinosinusitis.