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View this animation to see how a blow to the head may produce a contrecoup (counterblow) fracture of the basilar portion of the occipital bone on the base of the skull. Why may a basilar fracture be life threatening?

Facial bones of the skull

The facial bones of the skull form the upper and lower jaws, the nose, nasal cavity and nasal septum, and the orbit. The facial bones include 14 bones, with six paired bones and two unpaired bones. The paired bones are the maxilla, palatine, zygomatic, nasal, lacrimal, and inferior nasal conchae bones. The unpaired bones are the vomer and mandible bones. Although classified with the brain-case bones, the ethmoid bone also contributes to the nasal septum and the walls of the nasal cavity and orbit.

Maxillary bone

The maxillary bone    , often referred to simply as the maxilla (plural = maxillae), is one of a pair that together form the upper jaw, much of the hard palate, the medial floor of the orbit, and the lateral base of the nose (see [link] ). The curved, inferior margin of the maxillary bone that forms the upper jaw and contains the upper teeth is the alveolar process of the maxilla    ( [link] ). Each tooth is anchored into a deep socket called an alveolus. On the anterior maxilla, just below the orbit, is the infraorbital foramen. This is the point of exit for a sensory nerve that supplies the nose, upper lip, and anterior cheek. On the inferior skull, the palatine process    from each maxillary bone can be seen joining together at the midline to form the anterior three-quarters of the hard palate (see [link] a ). The hard palate    is the bony plate that forms the roof of the mouth and floor of the nasal cavity, separating the oral and nasal cavities.

Maxillary bone

This image shows the location and structure of the maxilla. A small image of the skull on the top left shows the maxilla in ochre yellow. A magnified view shows the detailed structure of the maxilla.
The maxillary bone forms the upper jaw and supports the upper teeth. Each maxilla also forms the lateral floor of each orbit and the majority of the hard palate.

Palatine bone

The palatine bone    is one of a pair of irregularly shaped bones that contribute small areas to the lateral walls of the nasal cavity and the medial wall of each orbit. The largest region of each of the palatine bone is the horizontal plate    . The plates from the right and left palatine bones join together at the midline to form the posterior quarter of the hard palate (see [link] a ). Thus, the palatine bones are best seen in an inferior view of the skull and hard palate.

Homeostatic imbalances

Cleft lip and cleft palate

During embryonic development, the right and left maxilla bones come together at the midline to form the upper jaw. At the same time, the muscle and skin overlying these bones join together to form the upper lip. Inside the mouth, the palatine processes of the maxilla bones, along with the horizontal plates of the right and left palatine bones, join together to form the hard palate. If an error occurs in these developmental processes, a birth defect of cleft lip or cleft palate may result.

Cleft lip is a common development defect that affects approximately 1:1000 births, most of which are male. This defect involves a partial or complete failure of the right and left portions of the upper lip to fuse together, leaving a cleft (gap).

A more severe developmental defect is cleft palate, which affects the hard palate. The hard palate is the bony structure that separates the nasal cavity from the oral cavity. It is formed during embryonic development by the midline fusion of the horizontal plates from the right and left palatine bones and the palatine processes of the maxilla bones. Cleft palate affects approximately 1:2500 births and is more common in females. It results from a failure of the two halves of the hard palate to completely come together and fuse at the midline, thus leaving a gap between them. This gap allows for communication between the nasal and oral cavities. In severe cases, the bony gap continues into the anterior upper jaw where the alveolar processes of the maxilla bones also do not properly join together above the front teeth. If this occurs, a cleft lip will also be seen. Because of the communication between the oral and nasal cavities, a cleft palate makes it very difficult for an infant to generate the suckling needed for nursing, thus leaving the infant at risk for malnutrition. Surgical repair is required to correct cleft palate defects.

Questions & Answers

How does the male organ develop
MADUBULA Reply
Hw does the male organ develop
MADUBULA
Review your questions madam
Aliyu
what is anaphylaxis?
Rugut Reply
different between drug and medicine
ado Reply
drugs have no medical application (cocaine, heroin, crystal meth). medicine have medical purpose (fentanyl, albuterol, aspirin, ect ect)
Jordan
medicine is a substance or preparation used in treating disease,drug is chemical compound medicine are drugs but all drugs are not medicines
Wafa
assalam o alaikum
Sidra
what happen to ECF and ICF regarding to OEDEMA
Zwanga Reply
what are the smooth muscles of the heart
Sintung Reply
stomach
Sidra
identify external features of kidney
saba Reply
kidney weight on males?
saba
3 to4 onz and 140 gram kidney wight.adult
StudyTime
and female ?
saba
Sle full name & treatment
Samim
Syplymic lupw erythematous
Samim
blood supply to spleen ?
saba
I known this disease of treatment
Samim
saba
StudyTime
g..
saba
do u know female kidney wight?
StudyTime
ya 135 g females
saba
Please help me
Samim
130 on male
saba
130g on male
saba
g samim
StudyTime
approximate 140grms in adultkidny wight
StudyTime
g samim
saba
no 130grms on male
saba
ok saba
StudyTime
yaha number ya email id send nh krty kia ?
StudyTime
wese saba kia krti Hyn ap?
StudyTime
mbbs
saba
good kaha sy
StudyTime
good saba khan
Shahab
Tom kya krti ho st?
saba
st means
StudyTime
your name?
saba
nursing
StudyTime
muskan
StudyTime
ok
saba
g
StudyTime
tum kya krti ho? muskan
saba
sis nursing
StudyTime
ok
saba
gv
StudyTime
good muskan
Shahab
ok bye I m studying
saba
sis contact number mil skts hy help kyliye,?
StudyTime
thanks
StudyTime
g saba
StudyTime
Define cranial nerves with oder
Javid
O-olfactory O-optic O-occumulator T-trochlear T-trigemenal A-abducent F-facial A-auditory G-glossopharyngeal V-vagus A-acessory
Aniee
opd mean?
Shahab
out patient department
mahesh
thnxx
Shahab
Ty Aniee singh
Javid
Ap sb us book s parhte h
Areeej
Read KD Tripathi book of Pharmacology.
mayank
Hello
mayank
CT Scan means
Sintung
what's health?
Sintung
hello
Philip
hi
Sintung
CT means - computerized tomography
Vivek
connective tissue
Dee
they link some body organs
Sintung
Difference between drug and medicine
Javid
hiii muskan
saba
what is tomography?
Gideon
tomography ☝
shahid
yes
Gideon
how hemolytic anemia cause due to gas gangrene?
Huma Reply
what's gangrene?
Sidra
why retro abdominal region called or named "flank "?
Huma Reply
list types epithelial tissue
Sangu Reply
Squeamus epithelial tissu Cubidal Columna Cilliated columna
Aliyu
squamous cuboidal columnar ciliated stratified
Ken
psuedostratified ciliated columnar stratified squamous transitional epithelium
Espinoza
peace maker of heart is?
shahid
electrical conduction ... sa node
Dee
squamous epithelial tissue.
Tariq
squamous, stratified epithelial tissue
Sintung
explain how hormonal control aids in homeostasis regarding fluids and electrolytes, internal organs, clinical application, edema electrolyte imbalance?
Hensheal Reply
someone to help me explain those
Hensheal
parathyroid hormone : Calcium uptake, H+ and PO-4 wasting thyroid hormone, cortisol for temperature regulation by acting on B.V
Kartik
also renin
Kartik
thanks
Hensheal
why retro abdominal region called flank?
Huma
it is just Anatomical terminology
Kartik
meaning side of body b/w rib cage and hip bone
Kartik
list down all the hormones secreted by adrenal gland
Odong Reply
adrenaline hormones
Sangu
adrenaline and noradrenaline
Sintung
The amount of blood pumped by the left ventricle of the heart in one contraction.
Javid Reply
how we can calculate the cardiac output
khater
and how do we calculate the strock valume
khater
stroke volume is not all the blood contained in the left ventricle; normally, only about two-thirds of the blood in the ventricle is expelled with each beat.
Javid
Cardiac output 5.5 l S. V 68.75 ml H. R 80bpm
Javid
If we consider SV 70, end systolic vol is about 15% of total(approx always) out of a total of 80-85 ml only 70ml is pumped per systole
Kartik
what is macrophages?and its function
Sajjad Reply
macrophages they are white blood cells that engulf dead cells in the body
patience
what is power stroke?
muravha
no idea
patience
what is the stroke volume of heart?
up
the amount of blood that enters the heart
Sintung
wrong^^ stroke volume is the amount of blood ejected from the left ventricle on a single contraction.
Jordan
If an autoimmune disorder targets the alpha cells, production of which hormone would be directly affected?
Samantha Reply
what is a muscle?
Gideon Reply
A band or bundle of fibrous tissue in a human or animal body that has the ability to contract, producing movement in or maintaining the position of parts of the body
Mody
ok
Gideon
what's endolphthamities and panophthalmities?
Gideon

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Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
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