Diploe

The diploe is the most porous, the softest, and most cavernous part. ❋ Unknown (2007)

The bone at the middle of the head is double, the hardest and most compact part being the upper portion, where it is connected with the skin, and the lowest, where it is connected with the meninx (dura mater); and from the uppermost and lowermost parts the bone gradually becomes softer and less compact, till you come to the diploe. ❋ Unknown (2007)

In many old skulls, however, the diploe is wanting altogether, and the two tables are amalgamated, and often very thin. ❋ Joseph Bell (1874)

The tough outer table is more difficult to cut than the softer and more vascular diploe, and the inner table is denser than either, but more brittle. ❋ Joseph Bell (1874)

Now retract the pyramid, lest it injure the dura-mater; continue the rotary motion, holding the instrument perpendicularly to the bone, withdrawing from time to time, to clean its teeth with the brush and to enable the Surgeon to sound the depth of the groove; -- and penetrate both the diploe and the internal table. ❋ Unknown (1863)

The division of the diploe can be readily recognized by the ease with which the instrument penetrates its substance and the bloody detritus which escapes. ❋ Unknown (1863)

The spongy middle plate must, like the diploe of the skull, have served to deaden the vibrations of a blow dealt from the outside. ❋ Hugh Miller (1829)

It consisted of three plates, or rather, like the human skull, of two solid plates, with a _diploe_ or spongy layer between. ❋ Hugh Miller (1829)

It consisted of its two well-marked tables of solid bone, corresponding in their dermal character, the outer to the cuticle, the inner to the true skin, and the intermediate cellular layer to the _rete mucosum_; but bearing an unmistakable analogy also, as a mechanical contrivance, to the two plates and the _diploe_ of the human skull. ❋ Hugh Miller (1829)

Classification as to Structure: a. Spongy - made up of bony processes called trabeculae giving it a porous appearance; found in the epiphysis and metaphysic of long bones, diploe of flat bones and in the medullary cavities b. ❋ Unknown (2009)

In adults, it is found in flat bones (sternum, ribs, clavicle), bones of pelvis, diploe of skull bones, in vertebrae and in proximal epiphysis of femur and humerus. ❋ Unknown (2009)

(granulations) grows below, and it grows from the diploe of the bone, and from the sound portion, provided the upper table alone be in a state of necrosis. ❋ Unknown (2007)

Thus (1.) it may be performed through the uninjured cranium in the hope of evacuating an abscess of the diploe or dura mater, or of relieving pressure caused by suppuration in the brain itself, or by extravasation into the brain or membranes; or (2.) it may be required in cases of punctured and depressed fracture for the purpose of removing projecting corners of bone and allowing elevation of the depressed portions; or (3.) it is sometimes used to remove a circular portion of bone in cases of epilepsy in which pain or tenderness is felt at some limited portion of the cranium. ❋ Joseph Bell (1874)

-- three distinct principles embodied, -- the principle of the two tables and _diploe_ of the human skull, -- the principle of the variously arranged coats of the human stomach, -- and the principle of Oliver ❋ Hugh Miller (1829)