A handbook of diseases of the nose and nasopharynx / by James B. Ball.

  • Ball, James B. (James Barry), 1849-1926.
Date:
1890
Catalogue details

Licence: Public Domain Mark

Credit: A handbook of diseases of the nose and nasopharynx / by James B. Ball. Source: Wellcome Collection.

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    The Maxillary Sinus, or Antrum of Highmore, is the largest of the sinuses. The cavity has a somewhat pyra- midal shape, the apex being directed outwards towards the malar process -and the base towards the nasal fossa. Its capacity varies much. Sometimes projecting laminse of bone cross the cavity and subdivide it. The relation of the sinus to the alveolar process is of much practical importance. In certain cases a layer of spongy bone separates the whole extent of the alveolar process from the wall of the cavity, in- creasing in thickness backwards towards the wisdom teeth, and still more, forwards, towards the incisor teeth, the latter being always the farthest from the cavity. The alveoli of the first and second molars are always the nearest, and mostly form conical projections into the cavity. Sometimes the sinus extends so far into the alveolar process, that the alveoli of all the teeth as far forwards as the canines, and inclusive of these, form little projections in the floor. Occa- sionally over certain roots the bone may be absent, and the fangs of the teeth may be separated from the cavity only by mucous membrane. The maxillary sinus communicates with the nose by a small opening, occasionally circular, more usually slit-like, being elongated from before backwards. This opens into the sinus near its roof, and into the middle meatus of the nose at the posterior part of the deep groove, known as the infundibulum, the margins of which, especially the lower, are here formed by projecting folds of mucous membrane, which are liable to swell and thus impede the escape of fluid from the sinus. A little below and behind this opening, a second opening of varying size exists, in about one case in every ten. The Frontal Sinus, situated between the outer and inner table of the frontal bone, resembles in shape a three- sided pyramid, the apex being directed upwards and the base being formed by the orbital plate. The sinus is separated from that of the opposite side by a thin septum,