The ossicles give the eardrum mechanical advantage via lever action and a reduction in the area of force distribution ; the resulting vibrations would be much smaller if the sound waves were transmitted directly from the outer ear to the oval window.

Freezing caused the brain of the man to be slightly swollen, and his inner ear ossicles were lost during preparation of the slices.

The classic example is the ear ossicles of mammals, which we know from palaeontological and embrological studies originated in the upper and lower jaws and the hyoid of their Synapsid ancestors, and further back still were part of the gill arches of early fish.

In most cases, the ossicles and the middle ear cavity were dysmorphic.

Larger flat scutes, conical plates, and disc-shaped plates were arranged in transverse bands among this pavement of ossicles.

These teeth also do not have separate tooth sockets but were apparently held by ligaments in a special tooth pad, that was also covered with small ossicles, or bone plates.

Image: Gray919. png | Chain of ossicles and their ligaments, seen from the front in a vertical, transverse section of the tympanum.

File: Gray919. png | Chain of ossicles and their ligaments, seen from the front in a vertical, transverse section of the tympanum.

Image: Gray919. png | Chain of ossicles and their ligaments, seen from the front in a vertical, transverse section of the tympanum.

The ossicles are essential for efficient coupling of sound waves into the cochlea, since the cochlea environment is a fluid – membrane system, and it takes more pressure to move sound through fluid – membrane waves than it does through air ; a pressure increase is achieved by the area ratio of the tympanic membrane to the oval window, resulting in a pressure gain of about 20 × from the original sound wave pressure in air.

Tympanoplasty is the surgical operation performed for the reconstruction of the eardrum ( tympanic membrane ) and / or the small bones of the middle ear ( ossicles ).

In chronic cases that are refractory to conservative treatment, surgical intervention yields good results, particularly for patients with bony or cartilaginous ossicles.

The ground-sloth theory can provide an explanation for its supposed bulletproof hide, as preserved ancient skin samples in the late 19th century revealed hard dermal ossicles, small pieces of bone in the skin of dinosaurs and alligators that protected them from predators.

The ossicles, minute calcareous plates embedded in the skin and characteristic of each species, can include wheel and anchor shapes.

It is composed of six parts ; the human skull, the ossicles of the middle ear, the hyoid bone of the throat, the rib cage, sternum and the vertebral column.

The cypriniformes ( family Cyprinidae ) are traditionally grouped with the Characiformes, Siluriformes and Gymnotiformes to create the superorder Ostariophysi, since these groups have certain common features, such as being found predominantly in fresh water and that they possess Weberian ossicles ( an anatomical structure originally made up of small pieces of bone formed from four or five of the first vertebrae ); the most anterior bony pair is in contact with the extension of the labyrinth and the posterior with the swimbladder.

It is believed that these muscles can contract to dampen the vibration of the ossicles, in order to protect the inner ear from excessively loud noise ( theory 1 ) and that they give better frequency resolution at higher frequencies by reducing the transmission of low frequencies ( theory 2 ) ( see acoustic reflex ).

The largest bone in the human body is the femur and the smallest bones are auditory ossicles.

Not all bones are interconnected directly: There are three bones in each middle ear called the ossicles that articulate only with each other.

The ossicles are classically supposed to mechanically convert the vibrations of the eardrum, into amplified pressure waves in the fluid of the cochlea ( or inner ear ) with a lever arm factor of 1. 3.

The ossicles ( also called auditory ossicles ) are the three smallest bones in the human body.

The ossicles are, in order from the eardrum to the inner ear ( from superficial to deep ): the malleus, incus, and stapes.

The dermis contains the ossicles ( bony plates ) which are rather loosely organised.

Like all echinoderms, sea cucumbers have an endoskeleton just below the skin, calcified structures that are usually reduced to isolated microscopic ossicles ( or sclerietes ) joined by connective tissue.

They are known as the introvert and posterior to them there is an internal ring of large calcareous ossicles.

The body wall consists of an epidermis and a dermis and contains smaller calcareous ossicles, the types of which are characteristics which help to identify different species.

Compliance measurement indicates how well the eardrum and ossicles ( the three ear bones ) are moving.

The ossicles which are connected to the eardrum pass the vibrations to the fluid-filled cochlea.

Forcible displacement of the stapes into the inner ear can cause a sensory neural hearing loss that cannot be corrected even if the ossicles are put back into proper position.

In ophiuroids, the calcite ossicles are fused to form armor plates which are known collectively as the test.

They are supported by an internal skeleton of calcium carbonate plates that are referred to as vertebral ossicles.

The ossicles are surrounded by a relatively thin ring of soft tissue, and then by four series of jointed plates, one each on the upper, lower, and the lateral surfaces of the arm.

# Type 3 involves removal of ossicles and epitympanum when there are large defects of the malleus and incus.

When it is fully developed in adult fish, the elements of the apparatus are sometimes collectively referred to as the Weberian ossicles.

The mobility of the ossicles may be impaired of different reasons and disruption of the ossicular chain due to trauma, infection or anchylosis may also result in hearing loss.

The auditory ossicles can also reduce sound pressure ( the inner ear is very sensitive to overstimulation ), by uncoupling each other through particular muscles.

Paralysis of the stapedius, such as in injury to the facial nerve ( CN VII ) distal to the geniculate ganglion prior to its branch to stapedius muscle ( which would also cause Bell's Palsy ), allows wider oscillation of the stapes, resulting in heightened reaction of the auditory ossicles to sound vibration.

The middle ear, an air-filled cavity behind the ear drum ( tympanic membrane ), includes the three ear bones or ossicles: the malleus ( or hammer ), incus ( or anvil ), and stapes ( or stirrup ).

At very high sound pressure levels, muscles in the ear tighten the tympanic membrane and this leads to a small change in the geometry of the ossicles and stirrup that results in lower transfer of force to the oval window of the inner ear ( the acoustic reflex ).

Once the vibrations reach the cochlea, the stirrup ( part of the ossicles ) puts pressure on the oval window.

It coalesces into small calcareous ossicles ( bony plates ), which can grow in all directions and thus can replace the loss of a body part.

Echinoderms have a mesodermal skeleton composed of calcareous plates or ossicles.

The mammalian middle ear contains three ossicles, which couple vibration of the eardrum into waves in the fluid and membranes of the inner ear.

The middle ear contains three tiny bones known as the ossicles: malleus, incus, and stapes.

The ossicles directly couple sound energy from the ear drum to the oval window of the cochlea.

See Evolution of mammalian auditory ossicles.

The movement of the ossicles may be stiffened by two muscles.

Nevertheless, it now appears that just as evolution tends to create new genes from parts of old genes ( molecular economy ), evo-devo demonstrates that evolution alters developmental processes to create new and novel structures from the old gene networks ( such as bone structures of the jaw deviating to the ossicles of the middle ear ) or will conserve ( molecular economy ) a similar program in a host of organisms such as eye development genes in molluscs, insects, and vertebrates.

If untreated, a cholesteatoma can eat into the three small bones located in the middle ear ( the malleus, incus and stapes, collectively called ossicles ), which can result in nerve deterioration, deafness, imbalance and vertigo.

The absence of the auditory ossicles would constitute a moderate-to-severe hearing loss.

The term " ossicles " literally means " tiny bones " and commonly refers to the auditory ossicles, though the term may refer to any small bone throughout the body.

Occasionally the joints between the ossicles become rigid.